인문학
사회과학
자연과학
공학
의약학
농수해양학
예술체육학
복합학
DBpia AI
AI 에이전트
AI 아이디어
AI 리더
AI 뷰어
Citeasy
크롬 서지관리 다운로드
지원사업
학술연구/단체지원/교육 등 연구자 활동을 지속하도록 DBpia가 지원하고 있어요.
커뮤니티
연구자들이 자신의 연구와 전문성을 널리 알리고, 새로운 협력의 기회를 만들 수 있는 네트워킹 공간이에요.
초록·키워드
In Bacillus subtilis, biofilm exopolysaccharide (EPS) is made by a 15-gene operon (epsA-O) that assembles, exports, and polymerizes EPS subunits. EpsA, encoded by the first gene in the operon, has multiple functions, including acting as a regulatory protein working in conjunction with the cytoplasmic tyrosine kinase EpsB. EpsA is a transmembrane protein that has an extracellular signal-sensing domain. Published work shows that purified EPS is able to interact with the EpsA signal sensing domain, suggesting a feedback regulation during EPS biosynthesis. In this study, we propose that oligosaccharide analogs, like aminoglycoside antibiotics, may inhibit biofilm formation by interrupting this pathway. Methods In this study, we constructed Bacillus subtilis strains that are resistant to different antibiotics, including kanamycin, neomycin, ampicillin, erythromycin, and spectinomycin, by adding resistance cassettes at the amyE site of the B. subtilis genome. We performed biofilm growth assays of wild-type and antibiotic resistant B. subtilis in the presence of their respective antibiotic types in biofilm inducing medium. To investigate the EPS produced by biofilms with and without antibiotics, we used light scattering to determine the lengths of the EPS chains produced by biofilms grown from kanamycin-resistant cells in the presence and absence of kanamycin. We also performed a sulfuric acid assay to quantify the amount of EPS produced by the strain in the same conditions. A growth curve comparing the growth of this strain was also performed to ensure that using kanamycin in the kanamycin resistant culture wasn't impacting growth. Results In our biofilm growth assays, biofilms that were grown in kanamycin and neomycin were defective and didn't form whereas biofilms grown in other antibiotics grew similar to wild-type biofilm. To further investigate why this may have happened, the EPS produced by kanamycin-resistant B. subtilis in the presence and absence of kanamycin was analyzed. Compared to wild-type, the amount of EPS produced by the kanamycin-resistant culture in the presence of kanamycin was significantly less than in the same strain without kanamycin. Additionally, the lengths of the EPS chains were significantly reduced. In shaking conditions, the growth curves for the strain with and without the presence of kanamycin were the same. Conclusion In our preliminary studies, we show that aminoglycoside antibiotics that exhibit a sugar-like structure, kanamycin and neomycin, inhibit biofilm formation even if the strain is resistant to the respective antibiotic. This inhibition was specific to aminoglycosides, not other antibiotic types. After further investigation of the EPS molecules produced by strains exposed to kanamycin by light scattering and sulfuric acid assays, it was determined that the presence of kanamycin greatly reduced EPS production and the EPS chains produced were of shorter length. We hypothesize that the oligosaccharide-like aminoglycosides are able to interfere with EPS polymerization, without impacting overall cell growth, as showed by a growth curve. This work reveals a potential second mode of action of aminoglycoside antibiotics by showing their ability to inhibit both cell growth, acting inside of the cell, and biofilm formation, acting outside of the cell on EPS biosynthesis. This work was supported by the National Science Foundation and the NSF Graduate Research Fellowship Program.
인공지능 문자 인식 모델을 통해 추출된 텍스트로, 일부 오타나 오류가 포함될 수 있으나 지속적으로 개선 중입니다.
오류를 발견하셨다면 해당 부분을 드래그한 후 ' 를 통해 신고해주세요.
오류를 발견하셨다면 해당 부분을 드래그한 후 ' 를 통해 신고해주세요.
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