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ISSN : 1226-9999(Print)
ISSN : 2287-7851(Online)
Korean J. Environ. Biol. Vol.43 No.1 pp.10-27
DOI : https://doi.org/10.11626/KJEB.2025.43.1.010

Discovery of 38 unreported bacterial species isolated from freshwater environments in Korea in 2024

Sumin Jang, Jaeduk Goh, Soo-Yeong Lee, Hyangmi Kim, Ja Young Cho, Ji Young Jung, Hye Kyeong Kang, Jung Hye Eom, Seoni Hwang, Ahyoung Choi*
Biological Resources Research Department, Nakdonggang National Institute of Biological Resources (NNIBR), Sangju 37242, Republic of Korea
*Corresponding author Ahyoung Choi Tel. 054-530-0841 E-mail. aychoi@nnibr.re.kr

Contribution to Environmental Biology


▪ Since the adoption of the Nagoya Protocol, the value of biological resources has increased.


▪ In this study, 38 unreported bacterial species in Korea were newly identified.


▪ Findings of this study can enhance our understanding of bacterial diversity in Korea’s freshwater environments.


09/12/2024 10/01/2025 04/02/2025

Abstract


As part of the 2024 research initiative, “Investigation and Discovery of Prokaryotes in Freshwater Systems,” samples were collected from diverse freshwater habitats, including both water and soil environments. Approximately 2,000 bacterial strains were isolated as single colonies and identified through 16S rRNA gene sequence analysis. Among these, 38 strains shared ≥98.7% 16S rRNA gene sequence similarities with those of known bacterial species not previously reported in Korea. These strains were thus categorized as newly recorded bacterial species in Korea. These 38 bacterial strains displayed significant phylogenetic diversities, spanning 2 phyla, 4 classes, 15 orders, 24 families, and 34 genera. These unrecorded species were classified into the following classes: Actinomycetia (with genera including Microcella, Conyzicola, Curtobacterium, Leucobacter, Microbacterium, Frigoribacterium, Lysinibacter, Streptomyces, Nonomuraea, Actinocorallia, Ruania, and Actinoplanes), Alphaproteobacteria (Paracoccus, Youngimonas, Loktanella, Corticibacterium, Neorhizobium, Onobrychidicola, Ferranicluibacter, Aureimonas, Asticcacaulis, and Novosphingobium), Betaproteobacteria (Rhodoferax, Rugamonas, and Cupriavidus), and Gammaproteobacteria (Rheinheimera, Shewanella, Kosakonia, Leclercia, Hafnia, Yersinia, Pseudomonas, Lysobacter, and Acinetobacter ). Further characterization included assessment of Gram reaction, colony and cell morphology, biochemical properties, and phylogenetic relationships. This report presents detailed phylogenetic and phenotypic characteristics of these bacterial species.


previously unreported bacteria , freshwater environments , 16S rRNA gene sequence analysis , phylogenetic diversity

초록

    1. INTRODUCTION

    To bolster national biological sovereignty, Korea’s Ministry of Environment (MOE) has set an ambitious goal to identify and catalog 100,000 native species by 2030. As of January 2024, 60,010 species-including 5,039 prokaryotic species-have been documented, with new discoveries continually adding to this figure (NIBR 2024). However, efforts in biological resource exploration have largely focused on marine and terrestrial ecosystems, highlighting the need for comprehensive investigations of prokaryotic species in freshwater environments within the country.

    Freshwater environments play a crucial role in maintaining ecological balance, supporting biodiversity, and providing essential ecosystem services such as water purification and nutrient cycling (Vanni 2021;An et al. 2022). Despite covering only a small fraction of the Earth’s surface, freshwater ecosystems are home to a disproportionately high number of species, including many microorganisms that remain largely unexplored (Abell et al. 2008;Li et al. 2021). Prokaryotic species, in particular, are crucial to ecosystem functioning, contributing to the breakdown of organic matter, biogeochemical cycling, and the regulation of water quality (Lewis et al. 2021;Dong et al. 2022;Yang et al. 2024). The exploration of prokaryotes in domestic freshwater environments is therefore not only important for advancing our understanding of microbial diversity (Baek et al. 2020;Kim et al. 2021), but also for uncovering species that may have significant ecological and biotechnological potential (Zheng et al. 2015;Datta et al. 2020). Freshwater resources are facing increasing pressures from climate change and human activities (Tockner 2021). As a result, understanding the microbial communities that drive key ecological processes within these habitats is crucial not only for conservation efforts but also for the sustainable management of freshwater ecosystems. Therefore, the discovery of prokaryotic species in freshwater environments offers valuable insights into ecosystem health, resilience, and the potential for harnessing microbial functions for environmental and industrial applications (Strayer and Dudgeon 2010;Tockner 2021).

    The bacterial phylum Actinomycetota, formerly known as ‘Actinobacteria’ (Oren and Garrity 2021), represents a diverse and ecologically significant group of Grampositive bacteria distinguished by their high guaninecytosine (G+C) content (Gao and Gupta 2012). These organisms thrive in terrestrial and aquatic ecosystems, contributing to various biological processes (Servin et al. 2008). Current classifications, based primarily on 16S rRNA gene analysis, indicate that Actinomycetota consists of six major classes: Acidimicrobiia, Actinomycetia, Coriobacteriia, Nitriliruptoria, Rubrobacteria, and Thermoleophilia. A defining feature of this phylum is the prominence of Streptomyces, a genus notable for its extensive metabolic capabilities and importance in soil ecology, particularly in nutrient cycling and maintaining soil structure (Bhattacharjee et al. 2023).

    Pseudomonadota, previously known as ‘Proteobacteria’ until its renaming in 2021 (Oren and Garrity 2021), is recognized as the largest and most phenotypically varied phylogenetic group. According to the latest taxonomic classification based on 16S rRNA gene sequences, this phylum is divided into six primary classes: Acidithiobacillia, Alphaproteobacteria, Betaproteobacteria, Gammaproteobacteria, Hydrogenophilalia, and Zetaproteobacteria. Known for its vast metabolic capabilities, this phylum is highly biologically significant, encompassing many Gram-negative species important in medical, veterinary, and industrial fields (Zhou et al. 2020).

    In this project, we collected physicochemical data and samples from various freshwater environments, including rivers, alluvial soils, wetlands, and lagoon areas. The aim was to identify 38 previously unreported species by isolating prokaryotes from water and soil samples. Genetic information from approximately 2,000 bacterial strains was analyzed using 16S rRNA gene sequencing. To ensure taxonomic validation, we also gathered transmission electron microscopy (TEM) images, culture data (such as medium type, temperature, and incubation period), and details for polyphasic classification analysis. This report outlines the phylogenetic and phenotypic profiles of these bacterial species.

    2. MATERIALS AND METHODS

    A total of 38 bacterial isolates were obtained from samples collected across various freshwater environments, including multiple river basins. For isolation, a standard serial dilution plating technique was employed on various culture media, including Marine Agar (MA), 1/10-diluted Marine Agar (1/10 MA), Reasoner’s 2A Agar (R2A), 1/10-diluted R2A (1/10 R2A), nutrient agar (NA), 1/10-diluted NA (1/10 NA), tryptic soy agar (TSA), 1/10-diluted tryptic soy agar (1/10 TSA), and Inorganic Salts Starch (ISP) Agar 4. The plates were incubated at temperatures ranging from 15°C to 25°C for up to 14 days. After incubation, colonies were isolated, purified, and maintained as single strains. All purified strains were cryopreserved in 20% glycerol at -80°C. Detailed strain information, including culture media and incubation conditions, is provided in Table 1.

    Colony morphology was assessed on the respective culture media plates using a magnifying lens once the bacterial cells reached their stationary growth phase. Cell shape and dimensions were further analyzed via transmission electron microscopy (Talos L120C; ThermoFisher Scientific, Whaltham, MA, USA). Gram staining was conducted using a commercial Gram-stain kit (bioMérieux, Marcy-I’Étoile, France), and biochemical properties were determined following the manufacturer’s protocol with API 20NE biochemical test strips (bioMérieux).

    For 16S rRNA sequence analysis, genomic DNA was isolated from the bacterial strains using the DNeasy Blood & Tissue Kit (Qiagen, Hilden, Germany), following the manufacturer’s instructions. Amplification of the 16S rRNA gene was performed via PCR using the universal bacterial primers 27F and 1492R (Frank et al. 2008). The resulting PCR products were sequenced using the Sanger method (Weisburg et al. 1991). Nearly full-length 16S rRNA gene sequences were analyzed through the “16S-based ID” service provided by EzBio- Cloud (Yoon et al. 2017), with a similarity threshold of 98.7%. Strains showing ≥98.7% sequence similarity to previously reported bacterial species, but unrecorded in Korea, were classified as newly identified bacterial species in Korea.

    For phylogenetic analysis, the 16S rRNA gene sequences from the isolates were aligned with those of reference-type strains using the Clustal_W algorithm, with manual refinements performed in EzEditor (Jeon et al. 2014). Phylogenetic trees were constructed based on these alignments using the neighbor-joining method (Saitou and Nei 1987) and the Kimura 2-parameter model (Kimura 1980), both implemented in MEGA 7.0 software (Kumar et al. 2016). The reliability of the phylogenetic trees was assessed through bootstrap analysis with 1,000 replicates (Felsenstein 1985).

    3. RESULTS AND DISCUSSION

    In this study, approximately 2,000 bacterial strains were analyzed using 16S rRNA gene sequence analysis. This analysis revealed that several strains represented either novel species or species previously unreported in Korea. Among these, 38 strains exhibited ≥98.7% 16S rRNA gene sequence similarity with species unrecorded in Korea. These strains were classified into 2 phyla, 4 classes, 15 orders, 24 families, and 34 genera. A summary of the taxonomic distribution and identification results is provided in Table 1.

    The unreported species were categorized into the following classes: Actinomycetia (including genera such as Microcella, Conyzicola, Curtobacterium, Leucobacter, Microbacterium, Frigoribacterium, Lysinibacter, Streptomyces, Nonomuraea, Actinocorallia, Ruania, and Actinoplanes), Alphaproteobacteria (Paracoccus, Youngimonas, Loktanella, Corticibacterium, Neorhizobium, Onobrychidicola, Ferranicluibacter, Aureimonas, Asticcacaulis, and Novosphingobium), Betaproteobacteria (Rhodoferax, Rugamonas, and Cupriavidus), and Gammaproteobacteria (Rheinheimera, Shewanella, Kosakonia, Leclercia, Hafnia, Yersinia, Pseudomonas, Lysobacter, and Acinetobacter).

    Phylogenetic trees illustrating the relationships of bacterial strains within the phylum Actinomycetota and their closely related species are shown in Fig. 1. Additionally, phylogenetic analyses of strains within Pseudomonadota are presented in Figs. 2 and 3. These figures depict the phylogenetic positions of the isolates with closely related reference species. Furthermore, transmission electron microscopy (TEM) images of selected isolates are displayed in Fig. 4.

    In conclusion, this study documents the identification of 38 bacterial species previously unreported in Korean freshwater ecosystems. The taxonomic and phenotypic characteristics of these species are presented and discussed in detail.

    3.1. Description of Microcella flavibacter 24SJ05W-101

    Cells are Gram-stain-positive, non-flagellated, and rod-shaped. Colonies grown on MA exhibit a smooth, round, convex surface and appear yellow after 3 days of incubation at 20°C. Positive for nitrate reduction, esculin hydrolysis, and β-galactosidase, but negative for indole production, glucose fermentation, arginine dihy-drolase, urease, and gelatinase. D-glucose, D-mannitol, and trisodium citrate are utilized. Does not utilize Larabinose, D-mannitol, N-acetyl-glucosamine, D-maltose, potassium gluconate, capric acid, adipic acid, malic acid, and phenylacetic acid. Strain 24SJ05W-101 displays the highest 16S rRNA gene sequence similarity with Microcella flavibacter WY83T (99.2%). Strain 24SJ 05W-101 (=NNIBR202411BA1564=FBCC-B17892) was isolated from the sediment of the river. The Gen Bank accession number of the 16S rRNA gene sequence is PP784620.

    3.2. Description of Conyzicola nivalis 24SJ02W-47

    Cells are Gram-stain-positive, non-flagellated, and rod-shaped. Colonies grown on R2A exhibit a circular, raised, filiform surface and appear transparent yellow after 4-5 days of incubation at 25°C. Positive for esculin hydrolysis and β-galactosidase, but negative for nitrate reduction, indole production, glucose fermentation, arginine dihydrolase, urease, and gelatinase. Malic acid is utilized. Does not utilize D-glucose, L-arabinose, D-mannose, D-mannitol, N-acetyl-glucosamine, Dmaltose, potassium gluconate, capric acid, adipic acid, trisodium citrate, and phenylacetic acid. Strain 24SJ 02W-47 displays the highest 16S rRNA gene sequence similarity with Conyzicola nivalis ZD5-4T (98.7%). Strain 24SJ02W-47 (=NNIBR202411BA2308=FBCCB18770) was isolated from the surface water of the river. The GenBank accession number of the 16S rRNA gene sequence is PP800272.

    3.3. Description of Curtobacterium ammoniigenes 24SJ02W-81

    Cells are Gram-stain-positive, non-flagellated, and rod-shaped. Colonies grown on MA exhibit a circular, raised surface with entire margins and appear white after 4-5 days of incubation at 25°C. Positive for esculin hydrolysis and β-galactosidase, but negative for nitrate reduction, indole production, glucose fermentation, arginine dihydrolase, urease, and gelatinase. D-mannitol, capric acid, and malic acid are utilized. Does not utilize D-glucose, L-arabinose, D-mannitol, N-acetyl-glucosamine, D-maltose, potassium gluconate, adipic acid, trisodium citrate, and phenylacetic acid. Strain 24SJ02 W-81 displays the highest 16S rRNA gene sequence similarity with Curtobacterium ammoniigenes NBRC 101786T (98.8%). Strain 24SJ02W-81 (=NNIBR2024 11BA2310=FBCC-B18772) was isolated from the surface water of the river. The GenBank accession number of the 16S rRNA gene sequence is PP800276.

    3.4. Description of Leucobacter aerolatus 24SJ02W-174

    Cells are Gram-stain-positive, non-flagellated, and rod-shaped. Colonies grown on MA exhibit a circular, raised surface with entire margins and appear white after 4-5 days of incubation at 25°C. Positive for esculin hydrolysis, but negative for nitrate reduction, indole production, glucose fermentation, arginine dihydrolase, urease, gelatinase, and β-galactosidase. Adipic acid is utilized. Does not utilize D-glucose, L-arabinose, Dmannose, D-mannitol, N-acetyl-glucosamine, D-maltose, potassium gluconate, capric acid, malic acid, trisodium citrate, and phenylacetic acid. Strain 24SJ02W- 174 displays the highest 16S rRNA gene sequence similarity with Leucobacter aerolatus Sj10T (99.9%). Strain 24SJ02W-174 (=NNIBR202411BA2312=FBCC-B18 774) was isolated from the surface water of the river. The GenBank accession number of the 16S rRNA gene sequence is PP800280.

    3.5. Description of Microbacterium radiodurans 24SJ03W-212

    Cells are Gram-stain-positive, non-flagellated, and rod-shaped. Colonies grown on MA exhibit a circular, raised surface with entire margins and appear ivory yellow after 4-5 days of incubation at 25°C. Positive for esculin hydrolysis and β-galactosidase, but negative for nitrate reduction, indole production, glucose fermentation, arginine dihydrolase, urease, and gelatinase. Dmannose, adipic acid and trisodium citrate are utilized. Does not utilize D-glucose, L-arabinose, D-mannitol, N-acetyl-glucosamine, D-maltose, potassium gluconate, capric acid, malic acid, and phenylacetic acid. Strain 24SJ03W-212 displays the highest 16S rRNA gene sequence similarity with Microbacterium radiodurans GIMN 1.002T (99.5%). Strain 24SJ03W-212 (=NNIBR2024 11BA2314=FBCC-B18776) was isolated from the surface water of the river. The GenBank accession number of the 16S rRNA gene sequence is PP800281.

    3.6. Description of Microbacterium hominis 24SH05W-142

    Cells are Gram-stain-positive, non-flagellated, and rod-shaped. Colonies grown on ISP4 exhibit a circular, convex, smooth surface and appear cream after 7 days of incubation at 25°C. Positive for esculin hydrolysis, gelatinase, and β-galactosidase, but negative for nitrate reduction, indole production, glucose fermentation, arginine dihydrolase, and urease. D-glucose, L-arabinose, D-mannose, D-mannitol, N-acetyl-glucosamine, Dmaltose, potassium gluconate, adipic acid, malic acid and trisodium citrate are utilized. Does not utilize capric acid and phenylacetic acid. Strain 24SH05W-142 displays the highest 16S rRNA gene sequence similarity with Microbacterium hominis NBRC 15708T (99.9%). Strain 24SH05W-142 (=NNIBR202411BA2236=FB CC-B18698) was isolated from the surface water of the river. The GenBank accession number of the 16S rRNA gene sequence is PQ084673.

    3.7. Description of Frigoribacterium faeni 24SJ19W-69

    Cells are Gram-stain-positive, non-flagellated, and rod-shaped. Colonies grown on MA exhibit a circular, convex, smooth surface and appear yellow after 7 days of incubation at 25°C. Positive for esculin hydrolysis and β-galactosidase, but negative for nitrate reduction, indole production, glucose fermentation, arginine dihydrolase, urease, and gelatinase. D-glucose, L-arabinose, D-mannose, D-mannitol, N-acetyl-glucosamine, potassium gluconate, malic acid and trisodium citrate are utilized. Does not utilize D-maltose, capric acid, adipic acid, and phenylacetic acid. Strain 24SJ19W-69 displays the highest 16S rRNA gene sequence similarity with Frigoribacterium faeni NBRC 103066T (99.4%). Strain 24SJ19W-69 (=NNIBR202411BA2234=FBCC-B18696) was isolated from the surface water of the river. The GenBank accession number of the 16S rRNA gene sequence is PQ084668.

    3.8. Description of Lysinibacter cavernae 24HG02W-86

    Cells are Gram-stain-positive, non-flagellated, and rod-shaped. Colonies grown on MA exhibit a smooth, convex, circular, entire margin surface and appear pale yellow after 3 days of incubation at 25°C. Positive for esculin hydrolysis and β-galactosidase, but negative for nitrate reduction, indole production, glucose fermentation, arginine dihydrolase, urease, and gelatinase. Dglucose, L-arabinose, D-mannose, D-mannitol, N-acetylglucosamine, D-maltose, potassium gluconate, adipic acid, and malic acid are utilized. Does not utilize capric acid, trisodium citrate, and phenylacetic acid. Strain 24HG02W-86 displays the highest 16S rRNA gene sequence similarity with Lysinibacter cavernae CC5- 806T (100%). Strain 24HG02W-86 (=NNIBR202411 BA1763=FBCC-B18090) was isolated from the surface water of the river. The GenBank accession number of the 16S rRNA gene sequence is PQ084686.

    3.9. Description of Streptomyces bungoensis 24SJ07S2-25

    Cells are Gram-stain-positive, non-flagellated, and rod-shaped. Colonies grown on 0.1 MA exhibit a filamentous, flat surface with undulated margins and appear brown after 4-5 days of incubation at 25°C. Positive for indole production, glucose fermentation, esculin hydrolysis, gelatinase, and β-galactosidase, but negative for nitrate reduction, arginine dihydrolase, and urease. D-glucose, L-arabinose, D-mannose, D-mannitol, Nacetyl- glucosamine, potassium gluconate, adipic acid, and malic acid are utilized. Does not utilize D-maltose, capric acid, trisodium citrate, and phenylacetic acid. Strain 24SJ07S2-25 displays the highest 16S rRNA gene sequence similarity with Streptomyces bungoensis DSM 41781T (99.8%). Strain 24SJ07S2-25 (=NNIBR202411 BA2316=FBCC-B18778) was isolated from the sediment of river. The GenBank accession number of the 16S rRNA gene sequence is PP800287.

    3.10. Description of Streptomyces xiamenensis 24SJ16W-76

    Cells are Gram-stain-positive, non-flagellated, and rod-shaped. Colonies grown on NA exhibit rough surfaces with elevated or raised centers and appear offwhite to grayish after 7 days of incubation at 25°C. Positive for esculin hydrolysis, gelatinase, and β-galactosidase, but negative for nitrate reduction, indole production, glucose fermentation, arginine dihydrolase, and urease. D-glucose, L-arabinose, D-mannose, D-mannitol, N-acetyl-glucosamine, D-maltose, potassium gluconate, adipic acid, malic acid and trisodium citrate are utilized. Does not utilize capric acid and phenylacetic acid. Strain 24SJ16W-76 displays the highest 16S rRNA gene sequence similarity with Streptomyces xiamenensis MCCC 1A01550T (99.8%). Strain 24SJ16W-76 (=NNIBR202411BA2233=FBCC-B18695) was isolated from the surface water of the river. The GenBank accession number of the 16S rRNA gene sequence is PQ084649.

    3.11. Description of Nonomuraea kuesteri 24GG04S-56

    Cells are Gram-stain-positive, non-flagellated, and rod-shaped. Colonies grown on R2A exhibit a rough surface and appear off-white to grayish after 2-3 days of incubation at 20°C. Positive for esculin hydrolysis and β-galactosidase, but negative for nitrate reduction, indole production, glucose fermentation, arginine dihydrolase, urease, and gelatinase. D-glucose, L-arabinose, D-mannose, D-mannitol, N-acetyl-glucosamine, potassium gluconate, adipic acid, malic acid, and trisodium citrate are utilized. Does not utilize D-maltose, capric acid, and phenylacetic acid. Strain 24GG04S-56 displays the highest 16S rRNA gene sequence similarity with Nonomuraea kuesteri NRRL B-24325T (99.9%). Strain 24GG04S-56 (=NNIBR202411BA1555=FBCCB17883) was isolated from the sediment of the river. The GenBank accession number of the 16S rRNA gene sequence is PQ084652.

    3.12. Description of Actinocorallia aurantiaca 24SH02S-20

    Cells are Gram-stain-positive, non-flagellated, and rod-shaped. Colonies grown on 0.1 TSA exhibit a circular, dry, flat, entire margin surface and appear ivory after 7 days of incubation at 25°C. Positive for glucose fermentation, but negative for nitrate reduction, indole production, arginine dihydrolase, urease, esculin hydrolysis, gelatinase, and β-galactosidase. Does not utilize D-glucose, L-arabinose, D-mannose, D-mannitol, Nacetyl- glucosamine, D-maltose, potassium gluconate, capric acid, adipic acid, malic acid, trisodium citrate, and phenylacetic acid. Strain 24SH02S-20 displays the highest 16S rRNA gene sequence similarity with Actinocorallia aurantiaca JCM 8201T (100%). Strain 24SH 02S-20 (=NNIBR202411BA2391=FBCC-B18854) was isolated from the sediment of the river. The GenBank accession number of the 16S rRNA gene sequence is PQ084677.

    3.13. Description of Ruania zhangjianzhongii 24SJ02W-74

    Cells are Gram-stain-positive, non-flagellated, and rod-shaped. Colonies grown on MA exhibit a circular, raised surface with entire margins and appear white after 4-5 days of incubation at 25°C. Positive for esculin hydrolysis and β-galactosidase, but negative for nitrate reduction, indole production, glucose fermentation, arginine dihydrolase, urease, and gelatinase. Does not utilize D-glucose, L-arabinose, D-mannose, D-mannitol, N-acetyl-glucosamine, D-maltose, potassium gluconate, capric acid, adipic acid, malic acid, trisodium citrate, and phenylacetic acid. Strain 24SJ02W-74 displays the highest 16S rRNA gene sequence similarity with Ruania zhangjianzhongii HY168T (99.5%). Strain 24SJ02W-74 (=NNIBR202411BA2309=FBCC-B18771) was isolated from the surface water of the river. The GenBank accession number of the 16S rRNA gene sequence is PP800273.

    3.14. Description of Actinoplanes ovalisporus 24SH05W-156

    Cells are Gram-stain-positive, non-flagellated, and rod-shaped. Colonies grown on NA exhibit a rough surface and appear pale orange after 7 days of incubation at 25°C. Positive for esculin hydrolysis, gelatinase, and β-galactosidase, but negative for nitrate reduction, indole production, glucose fermentation, arginine dihydrolase, and urease. D-glucose, L-arabinose, D-mannose, D-mannitol, D-maltose, potassium gluconate, capric acid and trisodium citrate are utilized. Does not utilize N-acetyl-glucosamine, adipic acid, malic acid, and phenylacetic acid. Strain 24SH05W-156 displays the highest 16S rRNA gene sequence similarity with Actinoplanes ovalisporus LDG1-06T (98.9%) Strain 24SH05W- 156 (=NNIBR202411BA2237=FBCC-B18699) was isolated from the surface water of the river. The Gen Bank accession number of the 16S rRNA gene sequence is PQ084671.

    3.15. Description of Paracoccus haematequi 23ND83S-74

    Cells are Gram-stain-negative, non-flagellated, and rod-shaped. Colonies grown on MA exhibit a smooth, circular, convex surface and appear light brown after 2-3 days of incubation at 25°C. Positive for nitrate reduction, esculin hydrolysis, and β-galactosidase, but negative for indole production, glucose fermentation, arginine dihydrolase, urease, and gelatinase. D-glucose, D-mannitol, potassium gluconate, and malic acid are utilized. Does not utilize L-arabinose, D-mannose, Nacetyl- glucosamine, D-maltose, capric acid, adipic acid, trisodium citrate, and phenylacetic acid. Strain 23ND 83S-74 displays the highest 16S rRNA gene sequence similarity with Paracoccus haematequi M1-83T (100%). Strain 23ND83S-74 (=NNIBR202411BA214=FBCCB16127) was isolated from the sediment of the river. The GenBank accession number of the 16S rRNA gene sequence is PP784578.

    3.16. Description of Youngimonas vesicularis 23ND78W-007

    Cells are Gram-stain-negative, non-flagellated, and rod-shaped. Colonies grown on 0.1 MA exhibit a circular raised surface and appear pale ivory after 7 days of incubation at 25°C. Positive for esculin hydrolysis, but negative for nitrate reduction, indole production, glucose fermentation, arginine dihydrolase, urease, gelatinase, and β-galactosidase. Does not utilize D-glucose, L-arabinose, D-mannose, D-mannitol, N-acetyl-glucosamine, D-maltose, potassium gluconate, capric acid, adipic acid, malic acid, trisodium citrate, and phenylacetic acid. Strain 23ND78W-007 displays the highest 16S rRNA gene sequence similarity with Youngimonas vesicularis CC-AMW-ET (99.9%). Strain 23ND78W- 007 (=NNIBR202411BA2617=FBCC-B19133) was isolated from the surface water of the river. The GenBank accession number of the 16S rRNA gene sequence is PP784650.

    3.17. Description of Loktanella fryxellensis 24SJ15W-35

    Cells are Gram-stain-negative, non-flagellated, and rod-shaped. Colonies grown on MA exhibit a circular, raised surface and appear ivory after 7 days of incubation at 25°C. Positive for esculin hydrolysis and β-galactosidase, but negative for nitrate reduction, indole production, glucose fermentation, arginine dihydrolase, urease, and gelatinase. Does not utilize D-glucose, Larabinose, D-mannose, D-mannitol, N-acetyl-glucosamine, D-maltose, potassium gluconate, capric acid, adipic acid, malic acid, trisodium citrate, and phenylacetic acid. Strain 24SJ15W-35 displays the highest 16S rRNA gene sequence similarity with Loktanella fryxellensis DSM 16213T (99.1%). Strain 24SJ15W-35 (=NNIBR202411BA2621=FBCC-B19129) was isolated from the surface water of the river. The GenBank accession number of the 16S rRNA gene sequence is PP800268.

    3.18. Description of Corticibacterium populi 24SJ05W-16

    Cells are Gram-stain-negative, non-flagellated, and rod-shaped. Colonies grown on 0.1 TSA exhibit a smooth, circular, convex surface and appear pale yellow after 2-3 days of incubation at 20°C. Positive for nitrate reduction, esculin hydrolysis and β-galactosidase, but negative for indole production, glucose fermentation, arginine dihydrolase, urease and gelatinase. D-glucose, L-arabinose, D-mannose, D-mannitol, and trisodium citrate are utilized. Does not utilize N-acetyl-glucosamine, D-maltose, potassium gluconate, capric acid, adipic acid, malic acid, and phenylacetic acid. Strain 24SJ 05W-16 displays the highest 16S rRNA gene sequence similarity with Corticibacterium populi 16B10-2-7T (98.9%). Strain 24SJ05W-16 (=NNIBR202411BA 1561=FBCC-B17889) was isolated from the surface water of the river. The GenBank accession number of the 16S rRNA gene sequence is PP784583.

    3.19. Description of Neorhizobium tomejilense 24SJ05W-87

    Cells are Gram-stain-negative, non-flagellated, and rod-shaped. Colonies grown on R2A exhibit a circular, smooth, slightly convex surface and appear white after 2-3 days of incubation at 20°C. Positive for nitrate reduction, urease, esculin hydrolysis, and β-galactosidase, but negative for indole production, glucose fermentation, arginine dihydrolase, and gelatinase. D-glucose, malic acid, and trisodium citrate are utilized. Does not utilize L-arabinose, D-mannose, D-mannitol, N-acetylglucosamine, D-maltose, potassium gluconate, capric acid, adipic acid, and phenylacetic acid. Strain 24SJ 05W-87 displays the highest 16S rRNA gene sequence similarity with Neorhizobium tomejilense T17_20T (98.8%). Strain 24SJ05W-87 (=NNIBR202411BA1563= FBCC-B17891) was isolated from the surface water of the river. The GenBank accession number of the 16S rRNA gene sequence is PP784584.

    3.20. Description of Onobrychidicola muellerharveyae 24SJ05S-81

    Cells are Gram-stain-negative, non-flagellated, and rod-shaped. Colonies grown on R2A exhibit a smooth, circular, convex shape with a shiny surface and appear cream-colored after 2-3 days of incubation at 20°C. Positive for nitrate reduction, urease, esculin hydrolysis, and β-galactosidase, but negative for indole production, glucose fermentation, arginine dihydrolase, and gelatinase. D-glucose, D-mannose, N-acetyl-glucosamine, and trisodium citrate are utilized. Does not utilize L-arabinose, D-mannitol, D-maltose, potassium gluconate, capric acid, adipic acid, malic acid, and phenylacetic acid. Strain 24SJ05S-81 displays the highest 16S rRNA gene sequence similarity with Onobrychidicola muellerharveyae TH2T (98.7%). Strain 24SJ05S-81 (=NNIBR202411BA1566=FBCC-B17894) was isolated from the sediment of the river. The GenBank accession number of the 16S rRNA gene sequence is PP800 261.

    3.21. Description of Ferranicluibacter rubi 24SJ01W-151

    Cells are Gram-stain-negative, non-flagellated, and rod-shaped. Colonies grown on ISP4 exhibit a circular, flat surface with entire margins and appear transparent white after 4-5 days of incubation at 25°C. Positive for esculin hydrolysis, but negative for nitrate reduction, indole production, glucose fermentation, arginine dihydrolase, urease, gelatinase, and β-galactosidase. Dglucose, L-arabinose, D-mannose, D-mannitol, D-maltose, and phenylacetic acid are utilized. Does not utilize N-acetyl-glucosamine, potassium gluconate, capric acid, adipic acid, malic acid, and trisodium citrate. Strain 24SJ 01W-151 displays the highest 16S rRNA gene sequence similarity with Ferranicluibacter rubi CRRU44T (99.2%). Strain 24SJ01W-151 (=NNIBR202411BA2307=FBCCB18769) was isolated from the surface water of the river. The GenBank accession number of the 16S rRNA gene sequence is PP800270.

    3.22. Description of Aureimonas psammosilenae 24SJ17W-65

    Cells are Gram-stain-negative, non-flagellated, and rod-shaped. Colonies grown on 0.1 R2A exhibit a smooth, flat surface and appear cream-colored after 7 days of incubation at 25°C. Positive for esculin hydrolysis and β-galactosidase, but negative for nitrate reduction, indole production, glucose fermentation, arginine dihydrolase, urease, and gelatinase. D-mannose, capric acid, and malic acid are utilized. Does not utilize D-glucose, L-arabinose, D-mannitol, N-acetyl-glucosamine, D-maltose, potassium gluconate, adipic acid, trisodium citrate, and phenylacetic acid. Strain 24SJ17W-65 displays the highest 16S rRNA gene sequence similarity with Aureimonas psammosilenae YIM DR1026T (99.4%). Strain 24SJ17W-65 (=NNIBR202411BA2231=FBCCB18693) was isolated from the surface water of the river. The GenBank accession number of the 16S rRNA gene sequence is PQ084584.

    3.23. Description of Asticcacaulis benevestitus 24SJ14S1-31

    Cells are Gram-stain-negative, non-flagellated, and rod-shaped. Colonies grown on 0.1 TSA exhibit a circular raised surface and appear ivory after 7 days of incubation at 25°C. Positive for nitrate reduction, esculin hydrolysis, and β-galactosidase, but negative for indole production, glucose fermentation, arginine dihydrolase, urease, and gelatinase. D-glucose and L-arabinose are utilized. Does not utilize D-mannose, D-mannitol, N-acetyl-glucosamine, D-maltose, potassium gluconate, capric acid, adipic acid, malic acid, trisodium citrate, and phenylacetic acid. Strain 24SJ14S1-31 displays the highest 16S rRNA gene sequence similarity with Asticcacaulis benevestitus DSM 16100T (99.9%). Strain 24SJ14S1-31 (=NNIBR202411BA2620=FBCCB19130) was isolated from the sediment of the river. The GenBank accession number of the 16S rRNA gene sequence is PP800267.

    3.24. Description of Novosphingobium aerophilum 24GG10W-27

    Cells are Gram-stain-negative, non-flagellated, and rod-shaped. Colonies grown on R2A exhibit a smooth, circular, convex, entire margin surface and appear yellow after 3 days of incubation at 25°C. Positive for esculin hydrolysis and β-galactosidase, but negative for nitrate reduction, indole production, glucose fermentation, arginine dihydrolase, urease, and gelatinase. Phenylacetic acid is utilized. Does not utilize D-glucose, Larabinose, D-mannose, D-mannitol, N-acetyl-glucosamine, D-maltose, potassium gluconate, capric acid, adipic acid, malic acid and trisodium citrate. Strain 24GG 10W-27 displays the highest 16S rRNA gene sequence similarity with Novosphingobium aerophilum 4Y4T (99.9%). Strain 24GG10W-27 (=NNIBR202411BA 1656=FBCC-B17983) was isolated from the surface water of the river. The GenBank accession number of the 16S rRNA gene sequence is PQ084676.

    3.25. Description of Rhodoferax aquaticus 24GG10W-27

    Cells are Gram-stain-negative, non-flagellated, and rod-shaped. Colonies grown on 0.1 MA exhibit a circular, convex surface with entire margins and appear white after 4-5 days of incubation at 25°C. Positive for esculin hydrolysis, but negative for nitrate reduction, indole production, glucose fermentation, arginine dihydrolase, urease, gelatinase, and β-galactosidase. L-arabinose, Nacetyl- glucosamine, adipic acid, malic acid, and phenylacetic acid are utilized. Does not utilize D-glucose, Dmannose, D-mannitol, D-maltose, potassium gluconate, capric acid and trisodium citrate. Strain 24SJ07S1-9 displays the highest 16S rRNA gene sequence similarity with Rhodoferax aquaticus Gr-4T (98.8%). Strain 24SJ07S1-9 (=NNIBR202411BA2315=FBCC-B18777) was isolated from the sediment of the river. The Gen Bank accession number of the 16S rRNA gene sequence is PP800282.

    3.26. Description of Rugamonas rubra MK31

    Cells are Gram-stain-negative, non-flagellated, and rod-shaped. Colonies grown on 0.1 NA exhibit a circular raised surface and appear bright yellow after 7 days of incubation at 25°C. Positive for esculin hydrolysis and β-galactosidase, but negative for nitrate reduction, indole production, glucose fermentation, arginine dihydrolase, urease, and gelatinase. D-glucose, L-arabinose, D-mannose, N-acetyl-glucosamine and D-maltose are utilized. Does not utilize D-mannitol, potassium gluconate, capric acid, adipic acid, malic acid, trisodium citrate, and phenylacetic acid. Strain MK31 displays the highest 16S rRNA gene sequence similarity with Rugamonas rubra ATCC 43154T (99.7%). Strain MK31 (=NNIBR202411BA2613=FBCC-B19137) was isolated from the surface water of the river. The GenBank accession number of the 16S rRNA gene sequence is PP800260.

    3.27. Description of Cupriavidus numazuensis 24GG02S-19

    Cells are Gram-stain-negative, non-flagellated, and rod-shaped. Colonies grown on 0.1 TSA exhibit a smooth, flat surface and appear yellow after 2-3 days of incubation at 20°C. Positive for esculin hydrolysis, but negative for nitrate reduction, indole production, glucose fermentation, arginine dihydrolase, urease, gelatinase, and β-galactosidase. D-glucose, L-arabinose, Dmannose, D-mannitol, N-acetyl-glucosamine, D-maltose, potassium gluconate, capric acid, adipic acid, malic acid, trisodium citrate, and phenylacetic acid are utilized. Strain 24GG02S-19 displays the highest 16S rRNA gene sequence similarity with Cupriavidus numazuensis TE26T (99.5%). Strain 24GG02S-19 (=NNIBR202411 BA1200=FBCC-B17717) was isolated from the sediment of the river. The GenBank accession number of the 16S rRNA gene sequence is PP784644.

    3.28. Description of Rheinheimera hassiensis 23ND71S-77

    Cells are Gram-stain-negative, non-flagellated, and rod-shaped. Colonies grown on MA exhibit a circular, smooth, slightly convex surface and appear pale yellow after 2-3 days of incubation at 20°C. Positive for nitrate reduction, arginine dihydrolase, esculin hydrolysis, gelatinase, and β-galactosidase, but negative for indole production, glucose fermentation, and urease. N-acetylglucosamine, D-maltose, and malic acid are utilized. Does not utilize D-glucose, L-arabinose, D-mannose, D-mannitol, potassium gluconate, capric acid, adipic acid, trisodium citrate, and phenylacetic acid. Strain 23ND71S-77 displays the highest 16S rRNA gene sequence similarity with Rheinheimera hassiensis E48T (98.7%). Strain 23ND71S-77 (=NNIBR202411BA 1557=FBCC-B17885) was isolated from the sediment of the river. The GenBank accession number of the 16S rRNA gene sequence is PP784576.

    3.29. Description of Rheinheimera baltica 24SH04W-16

    Cells are Gram-stain-negative, flagellated, and rodshaped. Colonies grown on 0.1 MA exhibit a smooth, circular, convex, entire margin surface and appear yellow after 3 days of incubation at 20°C. Positive for esculin hydrolysis, gelatinase, and β-galactosidase, but negative for nitrate reduction, indole production, glucose fermentation, arginine dihydrolase, and urease. Malic acid is utilized. Does not utilize D-glucose, Larabinose, D-mannose, D-mannitol, N-acetyl-glucosamine, D-maltose, potassium gluconate, capric acid, adipic acid, trisodium citrate, and phenylacetic acid. Strain 24SH04W-16 displays the highest 16S rRNA gene sequence similarity with Rheinheimera baltica DSM 14885T (99.3%). Strain 24SH04W-16 (=NNIBR202411BA 1878=FBCC-B18193) was isolated from the surface water of the river. The GenBank accession number of the 16S rRNA gene sequence is PQ084674.

    3.30. Description of Shewanella holmiensis 23ND78W-053

    Cells are Gram-stain-negative, non-flagellated, and rod-shaped. Colonies grown on 0.1 MA exhibit a circular raised surface and appear pale ivory after 7 days of incubation at 25°C. Positive for nitrate reduction, esculin hydrolysis, gelatinase, and β-galactosidase, but negative for indole production, glucose fermentation, arginine dihydrolase, and urease. D-glucose, L-arabinose, D-mannose, D-mannitol, N-acetyl-glucosamine, Dmaltose, potassium gluconate, adipic acid, malic acid, trisodium citrate, and phenylacetic acid are utilized. Does not utilize capric acid. Strain 23ND78W-053 displays the highest 16S rRNA gene sequence similarity with Shewanella holmiensis SP1S2-7T (99.2%). Strain 23ND78W-053 (=NNIBR202411BA2616=FBCC-B19 134) was isolated from the surface water of the river. The GenBank accession number of the 16S rRNA gene sequence is PP784649.

    3.31. Description of Shewanella oncorhynchi 24SJ11W-004

    Cells are Gram-stain-negative, flagellated, and rodshaped. Colonies grown on 0.1 MA exhibit a circular raised surface and appear ivory after 7 days of incubation at 25°C. Positive for nitrate reduction, esculin hydrolysis, and gelatinase, but negative for indole production, glucose fermentation, arginine dihydrolase, urease, and β-galactosidase. D-glucose, L-arabinose, D-mannose, D-mannitol, N-acetyl-glucosamine, D-maltose, potassium gluconate, adipic acid, malic acid, trisodium citrate, and phenylacetic acid are utilized. Does not utilize capric acid. Strain 24SJ11W-004 displays the highest 16S rRNA gene sequence similarity with Shewanella oncorhynchi S-1T (99.7%). Strain 24SJ11W-004 (=NNIBR 202411BA2618=FBCC-B19132) was isolated from the surface water of the river. The GenBank accession number of the 16S rRNA gene sequence is PP800265.

    3.32. Description of Kosakonia arachidis 23ND70W-8

    Cells are Gram-stain-negative, non-flagellated, and rod-shaped. Colonies grown on 0.1 MA exhibit a convex, round surface with entire margins and appear beige after 2-3 days of incubation at 20°C. Positive for nitrate reduction, glucose fermentation, esculin hydrolysis, and β-galactosidase, but negative for indole production, arginine dihydrolase, urease, and gelatinase. D-glucose, Larabinose, D-mannose, D-mannitol, N-acetyl-glucosamine, D-maltose, potassium gluconate, malic acid and trisodium citrate are utilized. Does not utilize capric acid, adipic acid and phenylacetic acid. Strain 23ND 70W-8 displays the highest 16S rRNA gene sequence similarity with Kosakonia arachidis Ah-143T (99.8%). Strain 23ND70W-8 (=NNIBR202411BA1556=FBCCB17884) was isolated from the surface water of the river. The GenBank accession number of the 16S rRNA gene sequence is PP784551.

    3.33. Description of Leclercia pneumoniae 24SJ06W-77

    Cells are Gram-stain-negative, non-flagellated, and rod-shaped. Colonies grown on TSA exhibit a smooth, circular, convex surface and appear light beige after 2-3 days of incubation at 20°C. Positive for nitrate reduction, glucose fermentation, arginine dihydrolase, esculin hydrolysis, and β-galactosidase, but negative for indole production, urease, and gelatinase. D-glucose, Larabinose, D-mannose, D-mannitol, N-acetyl-glucosamine, D-maltose, potassium gluconate, malic acid, and phenylacetic acid are utilized. Does not utilize capric acid, adipic acid, and trisodium citrate. Strain 24SJ06 W-77 displays the highest 16S rRNA gene sequence similarity with Leclercia pneumoniae 4-9-1-25T (99.3%). Strain 24SJ06W-77 (=NNIBR202411BA1567=FBCCB17895) was isolated from the surface water of the river. The GenBank accession number of the 16S rRNA gene sequence is PP784622.

    3.34. Description of Hafnia alvei 24SJ05W-46

    Cells are Gram-stain-negative, flagellated, and rodshaped. Colonies grown on ISP4 exhibit a smooth, round, convex shape with a moist surface and appear off-white to grayish after 2-3 days of incubation at 20°C. Positive for nitrate reduction, glucose fermentation, esculin hydrolysis, and β-galactosidase, but negative for indole production, arginine dihydrolase, urease, and gelatinase. D-glucose, L-arabinose, D-mannose, D-mannitol, Nacetyl- glucosamine, D-maltose, potassium gluconate, malic acid, trisodium citrate, and phenylacetic acid are utilized. Does not utilize capric acid and adipic acid. Strain 24SJ05W-46 displays the highest 16S rRNA gene sequence similarity with Hafnia alvei ATCC 13337T (99.6%). Strain 24SJ05W-46 (=NNIBR202411BA1562 =FBCC-B17890) was isolated from the surface water of the river. The GenBank accession number of the 16S rRNA gene sequence is PP784595.

    3.35. Description of Yersinia aldovae 24HG02W-70

    Cells are Gram-stain-negative, non-flagellated, and rod-shaped. Colonies grown on R2A exhibit a convex, smooth, circular, entire margin surface and appear milky white after 3 days of incubation at 25°C. Positive for esculin hydrolysis, but negative for nitrate reduction, indole production, glucose fermentation, arginine dihydrolase, urease, gelatinase, and β-galactosidase. Dglucose, D-mannose, and malic acid are utilized. Does not utilize L-arabinose, D-mannitol, N-acetyl-glucosamine, D-maltose, potassium gluconate, capric acid, adipic acid, trisodium citrate, and phenylacetic acid. Strain 24HG02W-70 displays the highest 16S rRNA gene sequence similarity with Yersinia aldovae ATCC 35236T (98.8%). Strain 24HG02W-70 (=NNIBR202411BA 1755=FBCC-B18082) was isolated from the surface water of the river. The GenBank accession number of the 16S rRNA gene sequence is PQ084685.

    3.36. Description of Pseudomonas iridis 24SJ06S-186

    Cells are Gram-stain-negative, non-flagellated, and rod-shaped. Colonies grown on NA exhibit a smooth, circular, convex surface and appear yellow after 2-3 days of incubation at 20°C. Positive for esculin hydrolysis and β-galactosidase, but negative for nitrate reduction, indole production, glucose fermentation, arginine dihydrolase, urease, and gelatinase. D-glucose, L-arabinose, D-mannose, N-acetyl-glucosamine, and D-maltose are utilized. Does not utilize D-mannitol, potassium gluconate, capric acid, adipic acid, malic acid, trisodium citrate, and phenylacetic acid. Strain 24SJ06S-186 displays the highest 16S rRNA gene sequence similarity with Pseudomonas iridis P42T (98.8%). Strain 24SJ06S- 186 (=NNIBR202411BA1569=FBCC-B17897) was isolated from the sediment of the river. The GenBank accession number of the 16S rRNA gene sequence is PP784630.

    3.37. Description of Lysobacter oligotrophicus 24SJ08S2-13

    Cells are Gram-stain-negative, flagellated, and rodshaped. Colonies grown on 0.1 MA exhibit a circular raised surface with entire margins and appear yellow after 4-5 days of incubation at 25°C. Positive for esculin hydrolysis and gelatinase, but negative for nitrate reduction, indole production, glucose fermentation, arginine dihydrolase, urease, and β-galactosidase. N-acetylglucosamine, potassium gluconate, adipic acid, and trisodium citrate are utilized. Does not utilize D-glucose, L-arabinose, D-mannose, D-mannitol, D-maltose, capric acid, malic acid, and phenylacetic acid. Strain 24SJ08 S2-13 displays the highest 16S rRNA gene sequence similarity with Lysobacter oligotrophicus 107-E2T (100%). Strain 24SJ08S2-13 (=NNIBR202411BA2319=FBCCB18781) was isolated from the sediment of the river. The GenBank accession number of the 16S rRNA gene sequence is PP800306.

    3.38. Description of Acinetobacter baylyi 23ND71W-36

    Cells are Gram-stain-negative, non-flagellated, and rod-shaped. Colonies grown on 0.1 NA exhibit a smooth, round, convex shape with a shiny surface and appear creamy white after 2-3 days of incubation at 20°C. Positive for nitrate reduction, but negative for indole production, glucose fermentation, arginine dihydrolase, urease, esculin hydrolysis, gelatinase, and β-galactosidase. D-glucose, capric acid, adipic acid, malic acid, and trisodium citrate are utilized. Does not utilize L-arabinose, D-mannose, D-mannitol, N-acetyl-glucosamine, D-maltose, potassium gluconate, and phenylacetic acid. Strain 23ND71W-36 displays the highest 16S rRNA gene sequence similarity with Acinetobacter baylyi DSM 14961T (98.8%). Strain 23ND71W-36 (=NNIBR202411 BN1478=FBCC-B17886) was isolated from the surface water of the river. The GenBank accession number of the 16S rRNA gene sequence is PP784577.

    ACKNOWLEDGEMENTS

    This study was supported by a grant from the Nakdonggang National Institute of Biological Resources (NNIBR), funded by the Ministry of Environment (MOE) of the Korea (NNIBR20251102).

    CRediT authorship contribution statement

    A Choi: Project administration, Conceptualization, Writing, Funding acquisition, Writing-Reviewing and editing. S Jang: Writing, Data curation. S-Y Lee, H Kim, JY Cho, JY Jung, HK Kang, JH Eom and S Hwang: Investigation, Data curation. J Goh: Supervision.

    Declaration of Competing Interest

    The authors declare no conflict of interest.

    Figure

    KJEB-43-1-10_F1.gif

    Neighbor-joining phylogenetic tree based on 16S rRNA gene sequences showing relationships of 14 strains isolated in this study and their relatives within the phylum Actinomycetota. Rheinheimera hassiensis E48T (GenBank accession No. JQ922423) was used as an outgroup. Bootstrap values (>70%) are indicated at nodes. The scale bar represents 0.02 substitutions per nucleotide position.

    KJEB-43-1-10_F2.gif

    Neighbor-joining phylogenetic tree based on 16S rRNA gene sequences showing relationships of 13 strains isolated in this study and their relatives within classes Alphaproteobacteria and Betaproteobacteria of the phylum Pseudomonadota. Microcella flavibacter WY83T (GenBank accession No. KT751087) was used as an outgroup. Bootstrap values (>70%) are indicated at nodes. The scale bar represents 0.02 substitutions per nucleotide position.

    KJEB-43-1-10_F3.gif

    Neighbor-joining phylogenetic tree based on 16S rRNA gene sequences showing relationships of 11 strains isolated in this study and their relatives within the class Gammaproteobacteria of the phylum Pseudomonadota. Microcella flavibacter WY83T (GenBank accession No. KT751087) was used as an outgroup. Bootstrap values (>70%) are indicated at nodes. The scale bar represents 0.02 substitutions per nucleotide position.

    KJEB-43-1-10_F4.gif

    Transmission electron micrographs of cells of strains isolated in this study. Scale bar sizes for each image are provided alongside their corresponding strain numbers as follows: (1) 24SJ05W-101, 0.5 μm; (2) 24SJ02W-47, 0.5 μm; (3) 24SJ02W-81, 0.5 μm; (4) 24SJ02W-174, 0.2 μm; (5) 24SJ03W-212, 0.5 μm; (6) 24SH05W-142, 0.2 μm; (7) 24SJ19W-69, 0.5 μm; (8) 24HG02W-86, 0.2 μm; (9) 24SJ07S2-25, 1.0 μm; (10) 24SJ16W-76, 0.5 μm; (11) 24GG04S-56, 2.0 μm; (12) 24SH02S-20, 0.5 μm; (13) 24SJ02W-74, 0.5 μm; (14) 24SH05W-156, 2.0 μm; (15) 23ND83S-74, 1.0 μm; (16) 23ND78W-007, 1.0 μm; (17) 24SJ15W-35, 0.5 μm; (18) 24SJ05W-16, 0.5 μm; (19) 24SJ05W-87, 1.0 μm; (20) 24SJ05S-81, 0.5 μm; (21) 24SJ01W-151, 1.0 μm; (22) 24SJ17W-65, 1.0 μm; (23) 24SJ14S1-31, 0.5 μm; (24) 24GG10W-27, 0.5 μm; (25) 24SJ07S1-9, 0.5 μm; (26) MK31, 0.2 μm; (27) 24GG02S-19, 0.2 μm; (28) 23ND71S-77, 0.5 μm; (29) 24SH04W-16, 0.5 μm; (30) 23ND78W-053, 0.5 μm; (31) 24SJ11W-004, 0.5 μm; (32) 23ND70W-8, 0.5 μm; (33) 24SJ06W-77, 0.5 μm; (34), 24SJ05W-46, 0.5 μm; (35) 24HG02W-70, 0.5 μm; (36) 24SJ06S-186, 0.5 μm; (37) 24SJ08S2-13, 0.5 μm; (38) 23ND71W-36, 0.5 μm.

    Table

    Summary of 38 isolates belonging to phyla Actinomycetota and Pseudomonadota, including their taxonomic affiliations, sources of isolation, and culture conditions

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    Vol. 40 No. 4 (2022.12)

    Journal Abbreviation 'Korean J. Environ. Biol.'
    Frequency quarterly
    Doi Prefix 10.11626/KJEB.
    Year of Launching 1983
    Publisher Korean Society of Environmental Biology
    Indexed/Tracked/Covered By

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