인문학
사회과학
자연과학
공학
의약학
농수해양학
예술체육학
복합학
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
Streptococcus pneumoniae is a human pathogen that has become increasingly resistant to synthetic fluoroquinolone antibiotics that target bacterial topoisomerases. To identify pathways essential under fluoroquinolone stress and potential novel targets to revitalize use of this antibiotic class, we perform genome-wide CRISPRi-seq screens and generate antibiotic-gene essentiality signatures. Expectedly, genes involved in DNA recombination and repair become more important under fluoroquinolone-induced DNA damage, including recA, recJ, recF, recO, rexAB, and ruvAB. Surprisingly, specific downregulation of the gene encoding the histidine kinase LiaS caused fluoroquinolone hypersensitivity. LiaS is part of the LiaFSR (VraTSR) three-component regulatory system involved in cell envelope homeostasis. We show that LiaS keeps the response regulator LiaR inactive, and that liaS deletion causes LiaR hyperphosphorylation and upregulation of the LiaR regulon. We use RNA-seq to refine the LiaR regulon, highlighting the role of heat-shock response and pleiotropic regulator SpxA2 in fluoroquinolone sensitivity. Activating the LiaR-regulon by the cell envelope-targeting antibiotic bacitracin synergized with ciprofloxacin and levofloxacin, restoring sensitivity in fluoroquinolone-resistant strains in vitro. Furthermore, bacitracin/levofloxacin combination therapy is effective in vivo and improved treatment of fluoroquinolone-resistant S. pneumoniae infection in a zebrafish meningitis model. These findings offer a starting point for identification and validation of potent combination therapies to treat antibiotic-resistant pneumococcal infections.
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.