SUNGKYUNKWAN UNIVERSITY SCHOOL OF MEDICINE

Acinetobacter baumannii received very little attention until the 1990s. Since its low virulence, it was not considered as a pathogenic bacteria. During the 21st century, the infection rate had been increasing for patients with weak immunity, especially in the intensive care units. This bacterium was also of great concern due to its strong antibiotics resistance. Although colistin had not been used because of its nephrotoxicity, it has been reintroduced to treat multi-drug resistant Gram-negative pathogens, including A. baumannii. Due to its unfamiliarity for some time, the antibiotic resistance of colistin was relatively low however, recent reports have shown that the resistance rate has been steadily rising. The research on colistin resistance and its resistance mechanism is actively being conducted and several genes associated with the resistance have been discovered. Then, we proved the resistance gene candidates by comparing the whole transcriptome between colistin-susceptible and resistant A. baumannii strains with further analyses.

 

[Selected Publications]

1. In Young Na,† Jungyu Seo,† Yanhong Jin, Kwan Soo Ko*, 2024: Whole-plasmid analysis of NDM-1-producing Acinetobacter seifertii isolate and its fitness in several Acinetobacter species. Journal of Global Antimicrobial Resistance, 38, 223-226 (Corresponding)

2. Shin JH, Shin D, Kwon KT, Ko KS*, 2024: Colistin heteroresistance in Citrobacter freundii clinical isolates from Republic of Korea. Diagnostic Microbiology and Infectious Disease, 108(4), 116187 (Corresponding)

3. Sun Ju Kim,† Jeongwoo Jo,† Jihyeon Kim, Kwan Soo Ko,* Wonsik Lee.*, 2024: Polymyxin B nonapeptide potentiates the eradication of Gram-negative bacterial persisters. Microbiology Spectrum, 12(4), e0368723 (Co-corresponding)

4. Seo J, Ko KS*, 2024: Development of colistin resistance via heteroresistance modeling in Klebsiella pneumoniae. Precision and Future Medicine, 8(1), 10-18

5. Baek JY, Yang J, Ko JH, Cho SY, Huh K, Chung DR, Peck KR, Ko KS*, Kang CI*, 2024: Extensively drug-resistant Enterobacter ludwigii co-harboring mcr-9 and a multicopy of blaIMP-1 in South Korea. Journal of Global Antimicrobial Resistance, 36(3), 217-222 (Co-
corresponding)

6. Seo J,† Na IY,† Ko KS*, 2024: Antibiotic efficacy in Escherichia coli and Klebsiella pneumoniae under nutrient limitation and effectiveness of colistin-based antibiotic combinations to eradicate persister cells. Current Microbiology, 81(1), 34 (Corresponding)

7. Park S, Choi J, Shin D, Kwon KT, Kim SH, Wi YM, Ko KS*, 2024: Conversion to colistin susceptibility by tigecycline exposure in colistin-resistant Klebsiella pneumoniae and its implications to combination therapy. International Journal of Antimicrobial Agents, 63(1), 107017 (Corresponding)

8. Kim SJ, Shin JH, Kim H, Ko KS*, 2024: Roles of crrAB two-component regulatory system in Klebsiella pneumoniae: Growth yield, survival in initial colistin treatment stage, and virulence. International Journal of Antimicrobial Agents, 63, 107011 (Corresponding)

9. Jong Hyun Shin, Sun Ju Kim, Gwanghun Kim, Hang-Rae Kim, and Kwan Soo Ko*., 2024: Machine learning using template-based-predicted structure of haemagglutinin predicts pathogenicity of avian influenza. Journal of Microbiology and Biotechnology, Accepted (Corresponding)

10. Jihyun Choi,† Jong Hyun Shin,† Suyeon Park, Ji Young Choi, Jin Yang Baek, Kyungmin Huh, Doo Ryeon Chung, Ki Tae Kwon, Mi-Ran Seo, Seung-Hyun Jung, Yeun-Jun Chung, Kwan Soo Ko*, 2024: Phylogenetic analysis based on whole genome sequences, antibiotic resistance, and virulence of Salmonella enterica clinical isolates from South Korea. Foodborne Pathogens and Disease, Accepted (Corresponding)

11. Jo J, Lee JY, Cho H, Ko KS*, 2023: Treatment of colistin dependence-developing Acinetobacter baumannii with antibiotic combinations at subinhibitory concentrations. Microbial Drug Resistance, 29(10), 448-455 (Corresponding)

12. Kim SJ, Jo J, Ko KS*, 2023: Lipid A modification-induced colistin-resistant Klebsiella variicola from healthy adults. Journal of Medical Microbiology, 72(6), 001680 (Corresponding)

13. Jo J, Kwon KT, Ko KS*, 2023: Multiple heteroresistance to tigecycline and colistin in Acinetobacter baumannii isolates and its implications for combined antibiotic treatment. Journal of Biomedical Science, 30, 37 (Corresponding)

14. Jo J, Park W, Kweon DH, Ko KS*, 2023: Development mechanism of resistant population post-exposure to tigecycline in tigecycline-heteroresistant Acinetobacter baumannii strain. International Journal of Antimicrobial Agents, 61(4), 106739 (Corresponding)

15. Kim SY, Seo HW, Park MS, Park CM, Seo J, Rho J, Myung S, Ko KS, Kim JS, Ryu CM, 2023: Exploitation of a novel adjuvant for polymyxin B against multidrug-resistant Acinetobacter baumannii. Journal of Antimicrobial Chemotherapy, 78(4), 923-932 (Co-author)

16. Cho YY, Ko KS*, 2023: ColE-type plasmid bearing blaOXA-232 increases persister cell formation. Journal of Global Antimicrobial Resistance, 32(3), 113-117 (Corresponding)

17. Park S, Ko KS*, 2023: Improvement of transformation efficency in hypermucoviscous Klebsiella pneumoniae using citric acid. Journal of Microbiological Methods, 205, 106673 (Corresponding)

18. Park S, Kim H, Ko KS*, 2023: Reduced virulence in tigecycline-resistant Klebsiella pneumoniae caused by overexpression of ompR and down-regulation of ompK35. Journal of Biomedical Science, 30, 22 (Corresponding)

19. Michidmaral Ganbold, Jungyu Seo, Yu Mi Wi, Ki Tae Kwon, Kwan Soo Ko*, 2023: Species identification, antibiotic resistance, and virulence in Enterobacter cloacae complex clinical isolates from South Korea. Frontiers in Microbiology, 14, 1122691 (Corresponding)

20. Seok H,† Choi JY,† Ganbold M, Shin JH, Kim J, Choi WS, Park DW, Ko KS*, 2023: Re-identification and characterization of multidrug-resistant Corynebacterium haemomassiliense-like organisms from humans. Current Microbiology, 80(2), 82 (Corresponding)

21. Kim H, Kim JH, Cho HB, Ko KS*, 2022: Overexpression of a DNA methyltransferase increases persister cell formation in Acinetobacter baumannii. Microbiology Spectrum, 10(6), e0265522 (Corresponding)

22. Cho YY*, Kim JH*, Kim H, Lee J, Im SJ*, Ko KS*, 2022: Comparison of Virulence between Two Main Clones (ST11 and ST307) of Klebsiella pneumoniae Isolates from South Korea. Microorganisms, 10, 1827 (Corresponding)

23. Kim SJ, Cho H*, Ko KS*, 2022: Comparative analysis of the colistin resistance-regulating gene cluster in Klebsiella species. Journal of Microbiology, 60(5), 461-468 (Corresponding)

24. Lee H, Ko KS*, 2021: Effect of multiple, compatible plasmids on the fitness of the bacterial host by inducing transcriptional changes. Journal of Antimicrobial Chemotherapy, 76(10), 2528&82112537 (Corresponding

25. Na IY, Kwon KT, Ko KS*, 2021: Plasmids carrying blaVIM-2 in Acinetobacter nosocomialis and A. seifertii isolates from South Korea. Microbial Drug Resistance, 27(9), 1186-1189 (Corresponding)

26. Jo J, Ko KS*, 2021: Tigecycline heteroresistance and resistance mechanism in clinical isolates of Acinetobacter baumannii. Microbiology Spectrum, 9, e01010-21 (Corresponding)

27. Kim JH, Cho YY, Choi JY, Wi YM, Ko KS*, 2021: Two distinct genotypes of KPC-2-producing Klebsiella pneumoniae isolates from South Korea. Antibiotics, 10, 911 (Corresponding)

28. Seo J, Wi YM, Kim JM, Kim YJ, Ko KS*, 2021: Detection of colistin-resistant populations prior to antibiotic exposure in KPC-2-producing Klebsiella pneumoniae clinical isolates. Journal of Microbiology, 59(6), 590-597 (Corresponding)

29. Jo J, Kim S, Ko KS*, 2021: High concentrations of divalent cations in extracellular environments reduce in vitro antibiotic activity of tigecycline. Journal of Bacteriology and Virology, 51(2), 74-78 (Corresponding)

30. Baek JY,† Kim SJ,† Shin J, Chung YJ, Kang CI, Chung DR, Song JH, Ko KS*, 2021: Genome-wide analysis of the temporal genetic changes in Streptococcus pneumoniae isolates of genotype ST320 and serotype 19A from South Korea. Microorganisms, 9(4), 795
(Corresponding)

31. Park S†, Lee H†, Shin D, Ko KS*. Change of hypermucoviscosity in the development of tigecycline resistance in hypervirulent Klebsiella pneumoniae Sequence Type 23 strains. Microorganisms 2020 8:1562.

32. Hong YK†, Kim H†, Ko KS*. Two types of colistin heteroresistance in Acinetobacter baumannii isolates. Emerging Microbes & Infections 2020 9(1): 2114-2123.

33. Choi Y, Lee JY, Lee H, Park M, Kang KJ, Lim SK, Shin D, Ko KS*. Comparison of fitness cost and virulence in chromosome- and plasmid-mediated colistin-resistant Escherichia coli. Frontiers in Microbiology 2020 11:798.

34. Baek MS, Chung ES, Jung DS, Ko KS*. Effect of colistin-based antibiotic combinations on the eradication of persister cells in Pseudomonas aeruginosa. Journal of Antimicrobial Chemotherapy 2020 75(4):917-924.

35. Lee H, Shin J, Chung YJ, Park M, Kang KJ, Baek JY, Shin D, Chung DR, Peck KR, Song JH, Ko KS*. Co-introduction of plasmids harbouring the carbapenemase genes, blaNDM-1 and blaOXA-232, increases fitness and virulence of bacterial host. Journal of Biomedical Science
2020 27:8.

36. Hae Suk Cheong, So Yeon Kim, Yu Mi Yi, Kyong Ran Peck, Kwan Soo Ko*. Colistin heteroresistance in Klebsiella pneumoniae isolates and diverse mutations of PmrAB and PhoPQ in resistant subpopulations. Journal of Clinical Medicine. 2019 8(9):1444.

37. Lee JY, Lee H, Park M, Cha CJ, Shin D Ko KS*. Lytic transglycosylase contributes to the survival of lipooligosaccharide (LOS)-deficient, colistin-dependent Acinetobacter baumannii. Clinical Microbiology and Infection 2019 25(9):1156.e1&82111156.e7.

38. Lee H, Shin J, Chung YJ, Baek JY, Chung DR, Peck KR, Song JH, Ko KS*. Evolution of Klebsiella pneumoniae with mucoid and non-mucoid type colonies within a single patient. International Journal of Medical Microbiology 2019 309:194-198.

39. Chung ES, Ko KS*. Eradication of persister cells of Acinetobacter baumannii through combination of colistin and amikacin antibiotics. Journal of Antimicrobial Chemotherapy 2019 74(5):1277-1283.

40. Kim SY, Ko KS*. Effects of prophage regions in a plasmid carrying a carbapenemase gene on survival against antibiotic stress. International Journal of Antimicrobial Agents 2019 53(1):89-94.

41. Kim SJ, Ko KS*. Diverse genetic alterations responsible for post-exposure colistin resistance in populations of the same strain of Klebsiella pneumoniae. International Journal of Antimicrobial Agents 2018 52(3):425-429.

42. Kim J, Lee JY, Lee H, Choi JY, Kim DH, Wi YM, Peck KR, Ko KS*. Microbiological features and clinical impact of the type VI secretion system (T6SS) in Acinetobacter baumannii isolates causing bacteremia. Virulence 2017 8(7):1378-1389.

 

(Tel) +82-31-299-6223,  (Email) ksko@skku.edu