MSK
Search
- Page Path
- HOME > Search
Journal Article
- Whole genome and RNA sequencing of oral commensal bacterium Streptococcus anginosus subsp. anginosus with vancomycin tolerance
- Kyu Hwan Kwack , Jae-Hyung Lee , Ji-Hoi Moon
- J. Microbiol. 2022;60(2):167-176. Published online January 7, 2022
- DOI: https://doi.org/10.1007/s12275-022-1425-4
- 27 View
- 0 Download
- 3 Citations
-
Abstract
- “Antibiotic tolerance” promotes the rapid subsequent evolution of “antibiotic resistance,” however, it is often overlooked because it is difficult to distinguish between tolerant and susceptible organisms. A commensal bacterium S. anginosus subsp. anginosus strain KHUD_S1, isolated from dental biofilm was found to exhibit a high MBC/MIC ratio of 32 against vancomycin. We observed KHUD_S1 cells exposed to vancomycin did not grow but maintained viability. Transmission electron microscope showed KHUD_S1 cells possessed a dense, thick capsule and maintained the cell wall integrity upon vancomycin exposure. To infer the underlying mechanisms of the vancomycin tolerance in KHUD_S1, we performed whole genome sequencing and RNA sequencing. The KHUD_S1 genome carried three genes encoding branching enzymes that can affect peptidoglycan structure through interpeptide bridge formation. Global gene expression profiling revealed that the vancomycin-induced downregulation of carbohydrate and inorganic ion transport/metabolism as well as translation is less prominent in KHUD_S1 than in the vancomycin susceptible strain KHUD_S3. Based on the transcriptional levels of genes related to peptidoglycan synthesis, KHUD_S1 was determined to have a 3D peptidoglycan architecture distinct from KHUD_S3. It was found that, under vancomycin exposure, the peptidoglycan was remodeled through changes in the interpeptide bridge and transpeptidation reactions. Collectively, these features of S. anginosus KHUD_S1, including a dense capsule and differential gene expression in peptidoglycan synthesis, may contribute to vancomycin tolerance. Our results showing the occurrence of vancomycin tolerance amongst oral commensal bacteria highlight the need for considering future strategies for screening of antibiotic tolerance as an effort to reduce antibiotic resistance.
Research Support, Non-U.S. Gov't
- NOTE] Regulatory Characteristics of the Vibrio vulnificus rtxHCA Operon Encoding a MARTX Toxin
- Jinseo Park , Seung Min Kim , Hee Gon Jeong , Sang Ho Choi
- J. Microbiol. 2012;50(5):878-881. Published online September 21, 2012
- DOI: https://doi.org/10.1007/s12275-012-2479-5
- 7 View
- 0 Download
- 7 Citations
-
Abstract
- Vibrio vulnificus MARTX encoded by rtxA, an open reading frame of the rtxHCA operon, is essential for virulence in vitro and in mice. In this study, a primer extension analysis revealed that transcription of the rtxHCA operon begins at a single site, and is under the direction of a single promoter, PrtxHCA. PrtxHCA activity appeared at the beginning of growth and reached a maximum in mid-exponential phase. PrtxHCA activity was induced by exposure to INT-407 cells, and the membrane fraction of INT-407 cells was the most effective for the induction.
First
Prev
TOP
