NaHCO3调节了边界性抗氧氨酸的金黄色葡萄球菌 (BORSA) 的bla操作子和β-乳糖敏感性
Selvi C Ersoy1,2, Sabrina L Madrigal3, Richard A Proctor4
1Division of Infection Disease, The Lundquist Institute at Harbor-UCLA Medical Center, Torrance, CA, USA.
The Journal of antimicrobial chemotherapy
|December 20, 2024
概括
碳酸 (NaHCO3) 通过抑制β-乳糖酶的产生,增强了边缘性抗氧黄球菌 (BORSA) 对某些β-乳糖酶的敏感性. 这一发现表明了针对特定MRSA感染的潜在治疗策略.
科学领域:
- 微生物学 微生物学
- 抗微生物耐药性 抗微生物耐药性
- 分子生物学分子生物学
背景情况:
- 耐甲基西林黄金葡萄球菌 (MRSA) 对大多数β-乳糖抗生素具有耐药性.
- 一个MRSA菌株的子集在二碳酸盐 (NaHCO3) 的存在下显示恢复了对β-乳酸盐的敏感性.
- 这种NaHCO3反应性与调节mecA/PBP2a表达和辅助基因有关,可能由bla操作子调节.
研究的目的:
- 为了研究NaHCO3对β-乳糖酶过度产生,mecA阴性,边缘性抗氧素的金黄色葡萄球菌 (BORSA) 菌株的bla操作子的特定影响.
- 了解基础上的调节机制NaHCO3介导的抗生素易感性变化.
主要方法:
- 最低抑制度 (MIC) 测试用于评估β-乳酸的敏感性.
- 定量逆转录PCR (RT-qPCR) 用于测量bla操作子基因表达 (blaZ,blaI,blaR1).
- 尼托塞芬酶测定以确定β-乳糖酶 (BlaZ) 活性.
主要成果:
- 在BORSA菌株中,NaHCO3治疗增加了对青素和青素的敏感性.
- NaHCO3 没有影响对氧沙林,塞法林,万科米辛或达普托米辛的敏感性.
- NaHCO3显著抑制了blaZ,blaI和blaR1基因的表达,并降低了总体β-乳糖酶的产生.
结论:
- NaHCO3 影响了 bla operon 基因表达,导致β-乳糖酶的产生减少,并改善了 BORSA 中的β-乳糖素敏感性.
- BlaI 和 blaR1 调节器被认为是 NaHCO3 诱导的 mecA 抑制的媒介.
- 需要进一步的研究,以充分阐明 NaHCO3 调节蓝色操作的精确机制.
相关概念视频
01:25Inducible Operons: lac Operon
7
The lac operon in Escherichia coli is a model for understanding inducible gene regulation and metabolic flexibility. It integrates local control by lactose and global regulation through catabolite repression, enabling E. coli to preferentially metabolize glucose when available and switch to lactose utilization when glucose is scarce.Structure and Function of the lac OperonThe lac operon contains three structural genes: lacZ (β-galactosidase), lacY (lactose permease), and lacA...
7
00:57Antibiotic Selection
52.3K
Overview
52.3K
01:30Development of Antibiotic Resistance
Antibiotic resistance is a major public health concern that arises when bacteria evolve mechanisms to withstand the effects of antibiotic treatments. This resistance can be intrinsic, acquired through genetic mutations, or transferred between bacteria via horizontal gene transfer. The development of antibiotic resistance poses significant challenges in treating bacterial infections and necessitates ongoing research to develop new therapeutic strategies.Intrinsic resistance occurs when bacterial...
02:09Operons
48.6K
Prokaryotes can control gene expression through operons—DNA sequences consisting of regulatory elements and clustered, functionally related protein-coding genes. Operons use a single promoter sequence to initiate transcription of a gene cluster (i.e., a group of structural genes) into a single mRNA molecule. The terminator sequence ends transcription. An operator sequence, located between the promoter and structural genes, prohibits the operon’s transcriptional activity if bound by...
48.6K
01:23Operon Model
The operon model represents a fundamental mechanism of gene regulation in prokaryotes, enabling coordinated expression of genes involved in related metabolic or functional pathways. Operons consist of structural genes, a promoter, and an operator, with transcription regulated by repressors, activators, and small effector molecules.Structure and Function of OperonsAn operon is a cluster of structural genes transcribed together under the control of a single promoter. The promoter region...
01:27Combined Effects of Drugs: Synergism
3.7K
Synergism is a useful mechanism where combining two or more drugs is more effective than each constituent used alone. Such combinations are also called supra-additive interactions. The drugs collectively enhance the final therapeutic effect by acting on different targets. Another advantage is that the low dose of each constituent drug is sufficient to achieve the desired effect. This helps reduce the duration of therapy and lower the adverse effects of these drugs.
Such synergistic combinations...
Such synergistic combinations...
3.7K