附属基因调节器 (agr) 组多态性在耐甲林金色葡萄球菌及其与生物膜形成的关联
Sharmin A Omer1, Aryan R Ganjo2, Sayran H Haji3
1Department of Clinical Analysis, College of Pharmacy, Hawler Medical University Erbil, Iraq. sharmen.omer@hmu.edu.krd.
Cellular and molecular biology (Noisy-le-Grand, France)
|April 28, 2024
概括
大多数抗甲素的黄金葡萄球菌 (MRSA) 菌株不会形成生物膜. 在这项研究中,没有发现主导的辅助基因调节器 (agr) I型与生物膜形成相关.
科学领域:
- 微生物学 微生物学
- 传染性疾病 传染性疾病
- 分子生物学分子生物学
背景情况:
- 甲素耐药黄金葡萄球菌 (MRSA) 是一个重要的病原体,导致社区和医院获得的感染.
- 辅助基因调节器 (agr) 系统控制着黄金葡萄球菌的毒性基因表达.
- 了解MRSA病毒性因素及其调节对于有效的治疗策略至关重要.
研究的目的:
- 为了描述Staphylococcus aureus分离体的表型特征.
- 为了确定辅助基因调节 (agr) 基因的患病率.
- 调查农业基因类型与MRSA中的生物膜形成之间的相关性.
主要方法:
- 从临床样本中分离和识别了100种金黄色葡萄球菌菌株.
- 现型特征包括生物膜形成,稳素素生产,过氧化耐药性,溶血活性,蛋白酶和脂酶活性.
- 在MRSA分离物中对辅助基因调节 (agr) 类型 (I,II,III,IV) 的基因定型.
主要成果:
- 在100个金黄色葡萄球菌分离物中,34个被确定为MRSA. 只有24%的分离物表现出生物膜的产生,强度不同.
- 生体膜产生的MRSA菌株显示出更高的抗生素耐药率.
- 最常见的是agri类型 (84%),其次是agriII (53%),agriIII (32%) 和agriIV (30%). AgrI与生物膜生产没有相关性.
结论:
- 大多数研究的MRSA分离物是非生物膜生产者.
- 辅助基因调节器I型是测试MRSA菌株中最占主导地位的类型.
- 没有观察到MRSA中占主导地位的农业I型和生物膜生产之间的相关性.
相关概念视频
Global Regulatory Systems
961
Global regulatory systems in bacteria enable rapid and coordinated responses to environmental changes by integrating sensory inputs with gene expression, ensuring efficient adaptation to fluctuating conditions. Key global regulatory mechanisms include regulons, two-component systems, sigma factors, and secondary messengers.Regulons and Global RegulatorsA regulon is a collection of genes and operons controlled by a common global regulator. These regulators enable bacteria to prioritize resource...
961
Gene Regulation in Microbial Communities: Quorum Sensing
960
Quorum sensing is a mechanism of bacterial communication that enables coordinated gene expression in response to changes in population density. This facilitates collective behaviors that enhance survival, resource acquisition, and ecological adaptation. This process relies on small signaling molecules called autoinducers that accumulate as bacterial populations grow. When a critical threshold concentration of autoinducers is reached, bacterial cells collectively modify gene expression,...
960
Regulation of Bacterial Virulence
80
Pathogenic bacteria employ a range of regulatory mechanisms to modulate the expression of virulence genes in response to environmental and host-derived signals. These mechanisms ensure that virulence factors are expressed only under favorable conditions, thereby optimizing infection and survival strategies.Mechanisms of Virulence RegulationKey regulatory strategies include:Two-Component Systems: These consist of a membrane-bound sensor kinase and a cytoplasmic response regulator. Environmental...
80
Staphylococcal Skin Infections
150
Staphylococcus aureus is a Gram-positive coccus that resides harmlessly on the skin and mucous membranes of healthy individuals. When the skin barrier is breached, it can shift from a commensal to an opportunistic pathogen. This transition is facilitated by surface adhesins, such as clumping factor B and S. aureus surface protein G (SasG), which bind to structural proteins, including loricrin and cytokeratin, in the damaged epidermis. Protein A, another key factor, binds the Fc region of...
150
Mechanism of Antibiotic Resistance in MRSA
245
Antibiotic resistance in bacteria arises when microorganisms evolve the ability to withstand drugs designed to kill them or inhibit their growth, rendering once-effective treatments useless. This phenomenon, driven by genetic change and selection under antibiotic exposure, poses a profound threat to modern medicine. Mechanisms include drug-inactivating enzymes (e.g., β-lactamases), efflux pumps that eject antibiotics, mutations altering antibiotic targets, decreased drug uptake, and...
245
Clinical Significance of Antibiotic Resistance
106
Methicillin-resistant Staphylococcus aureus (MRSA) presents a critical public health threat, arising from its capacity to resist β-lactam antibiotics due to acquisition of the mecA gene within the staphylococcal cassette chromosome mec (SCCmec). This gene encodes penicillin-binding protein 2a (PBP2a), which impairs binding efficacy of methicillin and other β-lactams. MRSA has evolved into distinct clonal lineages impacting humans and animals alike, reinforcing its significance within...
106


