期刊
ANTIMICROBIAL AGENTS AND CHEMOTHERAPY
卷 65, 期 10, 页码 -出版社
AMER SOC MICROBIOLOGY
DOI: 10.1128/AAC.01019-21
关键词
Acinetobacter baumannii; human serum; albumin; carbapenem resistance; competence; natural transformation
资金
- NIH [SC3GM125556, R01AI100560, R01AI063517, R01AI072219, 2R15 AI047115]
- Cleveland Department of Veterans Affairs [1I01BX001974]
- Biomedical Laboratory Research and Development Service of the VA Office of Research and Development
- Geriatric Research Education and Clinical Center VISN 10
- CONICET
HSA enhances natural transformation and modifies the expression levels of competence genes and antibiotic resistance in Acinetobacter baumannii. When combined with carbapenems, HSA increases the expression of genes involved in natural competence, potentially accelerating the acquisition of foreign DNA and evolution in A. baumannii.
Acinetobacter baumannii A118, a carbapenem-susceptible strain, and AB5075, carbapenem resistant, were cultured in lysogeny broth (LB) or LB with different supplements, such as 3.5% human serum albumin (HSA), human serum (HS), meropenem, or meropenem plus 3.5% HSA. Natural transformation levels were enhanced in A. baumannii A118 and AB5075 cultured in medium supplemented with 3.5% HSA. Addition of meropenem plus 3.5% HSA caused synergistic enhancement of natural transformation in A. baumannii A118. Medium containing 3.5% HSA or meropenem enhanced the expression levels of the competence and type IV pilus-associated genes. The combination meropenem plus 3.5% HSA produced a synergistic enhancement in the expression levels of many of these genes. The addition of HS, which has a high content of HSA, was also an inducer of these genes. Cultures in medium supplemented with HS or 3.5% HSA also affected resistance genes, which were expressed at higher or lower levels depending on the modification required to enhance resistance. The inducing or repressing activity of these modulators also occurred in three more carbapenem-resistant strains tested. An exception was the A. baumannii AMA16 bla(NDM-1) gene, which was repressed in the presence of 3.5% HSA. In conclusion, HSA produces an enhancement of natural transformation and a modification in expression levels of competence genes and antibiotic resistance. Furthermore, when HSA is combined with carbapenems, which may increase the stress response, the expression of genes involved in natural competence is increased in A. baumannii. This process may favor the acquisition of foreign DNA and accelerate evolution.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据