Freshwater environments serve as crucial habitats for diverse microorganisms, playing essential roles alongside plants and animals within the ecosystem. Bacteria in these environments are particularly important for maintaining ecosystem functions. Among them, members of the phylum Pseudomonadota are known to be involved in processes such as nitrogen fixation, ammonia oxidation, and biofilm formation. Pseudomonadota comprises six classes: Acidithiobacillia, Alphaproteobacteria, Betaproteobacteria, Gammaproteobacteria, Hydrogenophilia, and Zetaproteobacteria. This study reports 43 previously unrecorded species belonging to the phylum Pseudomonadota. They were isolated from various freshwater habitats in Republic of Korea. These strains were isolated and cultured using nine different standard media, with classification based on Gram staining, cell morphology, and biochemical characteristics. Species identity was determined using 16S rRNA gene sequencing, with a similarity threshold of 98.7% for designation as unreported species. Phylogenetic analysis revealed that these 43 strains were distributed across three classes, 13 orders, 28 families, and 39 genera. This research emphasizes microbial diversity in freshwater ecosystems and provides valuable insights into ecological roles and potential novel functions of unreported bacterial species in Korea.

Abstract
1. INTRODUCTION
2. MATERIALS AND METHODS
3. RESULTS AND DISCUSSION
    3.1. Description of Asticcacaulis taihuensis21LS1-75
    3.2. Description of Pelagimonas variansLW3-33
    3.3. Description of Loktanella salsilacusSJW1-31
    3.4. Description of Donghicola mangrovi6LW2-50
    3.5. Description of Cypionkella sinensis21YS10S-0N32
    3.6. Description of Kandeliimicrobium roseumLS9-139
    3.7. Description of Tabrizicola oligotrophica23ND62S-17
    3.8. Description of Rhodobacter ruber23ND45S-58
    3.9. Description of Neoroseomonas marina23ND67S-41
    3.10. Description of Roseomonas fluvialis23ND27W-51
    3.11. Description of Azospirillum doebereinerae23ND38W-51
    3.12. Description of Lacibacterium aquatile23ND68W-85
    3.13. Description of Rhodospirillum rubrum23ND04W-104
    3.14. Description of Aestuariivirga litoralis21LW3-03
    3.15. Description of Siculibacillus lacustris23ND46W-43
    3.16. Description of Aureimonas altamirensisLS1-96
    3.17. Description of Pedomicrobiumaustralicum SW3-15
    3.18. Description of Kaistia hirudinis UTW7-4
    3.19. Description of Bradyrhizobiumoligotrophicum 23ND22S-21
    3.20. Description of Rhizobium tumorigenesLS1-8
    3.21. Description of Rhizobium rhizoryzae23ND69W-100
    3.22. Description of Rhizobium azooxidifex23ND70S-60
    3.23. Description of Hoeflea marina LW1-19
    3.24. Description of Hoeflea olei 22LW2-114
    3.25. Description of Angulomicrobiumtetraedrale 23ND67S-26
    3.26. Description of Novosphingobiumarvoryzae 21LS1-37
    3.27. Description of Vogesella mureinivoransUTW7-1
    3.28. Description of Duganella sacchari23ND41W-8
    3.29. Description of Herminiimonas aquatilis21LW1-65
    3.30. Description of Rhodoferax antarcticusHRW3-6
    3.31. Description of Xenophilusarseniciresistens CS-27
    3.32. Description of Inhella crocodyli ADW1-35
    3.33. Description of Pelomonas aquatic23ND37W-67
    3.34. Description of Aromatoleumtolulyticum ADS2-16
    3.35. Description of Rheinheimera riviphila21SJ05W-0M51
    3.36. Description of Kluyvera sichuanensis23ND70W-93
    3.37. Description of Hafnia psychrotolerans22LW2-120
    3.38. Description of Arenimonas metalli23ND71S-1
    3.39. Description of Stenotrophomonas terraeHRW4-14
    3.40. Description of Dyella amyloliquefaciens21LS8-45
    3.41. Description of Steroidobacter soliDCSS-21
    3.42. Description of Pseudomonaswadenswilerensis 21SJ07S-11
    3.43. Description of Pseudomonas capsici23ND69W-112
CRediT authorship contribution statement
Declaration of Competing Interest
ACKNOWLEDGEMENTS
REFERENCES

• Jaeduk Goh(Biological Resources Research Department, Nakdonggang National Institute of Biological Resources (NNIBR), Sangju 37242, Republic of Korea)
• Seoni Hwang(Biological Resources Research Department, Nakdonggang National Institute of Biological Resources (NNIBR), Sangju 37242, Republic of Korea)
• Ja Young Cho(Biological Resources Research Department, Nakdonggang National Institute of Biological Resources (NNIBR), Sangju 37242, Republic of Korea)
• Ji Young Jung(Biological Resources Research Department, Nakdonggang National Institute of Biological Resources (NNIBR), Sangju 37242, Republic of Korea)
• Hyangmi Kim(Biological Resources Research Department, Nakdonggang National Institute of Biological Resources (NNIBR), Sangju 37242, Republic of Korea)
• Ahyoung Choi(Biological Resources Research Department, Nakdonggang National Institute of Biological Resources (NNIBR), Sangju 37242, Republic of Korea)
• Soo-Yeong Lee(Biological Resources Research Department, Nakdonggang National Institute of Biological Resources (NNIBR), Sangju 37242, Republic of Korea) Corresponding author