The role of Zur-regulated lipoprotein A in bacterial morphology, antimicrobial susceptibility, and production of outer membrane vesicles in Acinetobacter baumannii

BMC Microbiology

Nayeong Kim¹  Hyo Jeong Kim¹  Se Yeon Kim¹  Minsang Shin¹  Joo Hee Son¹  Mi Hyun Kim¹  Je Chul Lee¹  Yoo Chul Lee¹  Man Hwan Oh²  Seung Il Kim³ 

[1] Department of Microbiology, School of Medicine, Kyungpook National University;Department of Nanobiomedical Science, Dankook University;Drug & Disease Target Team, Korea Basic Science Institute;

关键词: Acinetobacter baumannii;    Zur-regulated gene;    ZrlA;    Carboxypeptidase;    Outer membrane vesicle;   

DOI  :  10.1186/s12866-020-02083-0

来源: DOAJ

【 摘 要 】

Abstract Background Zinc uptake-regulator (Zur)-regulated lipoprotein A (ZrlA) plays a role in bacterial fitness and overcoming antimicrobial exposure in Acinetobacter baumannii. This study further characterized the zrlA gene and its encoded protein and investigated the roles of the zrlA gene in bacterial morphology, antimicrobial susceptibility, and production of outer membrane vesicles (OMVs) in A. baumannii ATCC 17978. Results In silico and polymerase chain reaction analyses showed that the zrlA gene was conserved among A. baumannii strains with 97–100% sequence homology. Recombinant ZrlA protein exhibited a specific enzymatic activity of D-alanine-D-alanine carboxypeptidase. Wild-type A. baumannii exhibited more morphological heterogeneity than a ΔzrlA mutant strain during stationary phase. The ΔzrlA mutant strain was more susceptible to gentamicin than the wild-type strain. Sizes and protein profiles of OMVs were similar between the wild-type and ΔzrlA mutant strains, but the ΔzrlA mutant strain produced 9.7 times more OMV particles than the wild-type strain. OMVs from the ΔzrlA mutant were more cytotoxic in cultured epithelial cells than OMVs from the wild-type strain. Conclusions The present study demonstrated that A. baumannii ZrlA contributes to bacterial morphogenesis and antimicrobial resistance, but its deletion increases OMV production and OMV-mediated host cell cytotoxicity.

【 授权许可】

Unknown