从肉中分离的Staphylococcus pseudintermedius不同农业群体之间的β-乳糖酶生产
Roghaiyeh Akbari1, Sahar Nouri Gharajalar2, Masoumeh Firouzamandi2
1Faculty of Veterinary Medicine, University of Tabriz, Tabriz, Iran.
Microbial pathogenesis
|November 21, 2024
概括
动物中常见的细菌Staphylococcus pseudintermedius在肉中被发现. 它的blaZ基因与抗生素耐药性有关,在agr型I中表达更高,这表明agr活性与抗生素β-lactam耐药性之间存在联系.
科学领域:
- 兽医微生物学 兽医微生物学
- 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:
- 伪中间体葡萄球菌 (Staphylococcus pseudintermedius) 是一种在动物皮肤和粘膜上发现的机会性病原体.
- 在S. pseudintermedius中,β-lactam抗生素耐药性通常与β-lactamase酶的产生有关.
- 农业系统在葡萄球菌基因表达的毒性和调节中发挥作用.
研究的目的:
- 在肉中识别S. pseudintermedius.
- 为了确定 blaZ 基因的患病率,该基因负责β-乳酸盐耐药性.
- 为了研究agr类型和blaZ基因表达之间的关系.
主要方法:
- 从肉的鼻子抽样被收集用于细菌识别,使用核基因的PCR放大.
- 对隔离物进行了抗生素敏感性测试和blaZ基因检测.
- 多重PCR用于确定agr类型,并量化了相对blaZ基因表达.
主要成果:
- 在66%的样本中确定了S. pseudintermedius,其中63%的样本由于blaZ基因而表现出青素耐药性.
- 大多数blaZ阳性分离物属于ag型I (70%).
- 与其他类型相比,在agr型I分离物中观察到明显更高的blaZ基因表达.
结论:
- 这项研究报告了首次从肉的鼻腔中分离出S. pseudintermedius.
- 这些发现表明,农业活动,特别是在农业类型I中,可能会影响S. pseudintermedius中的β-乳糖抗生素耐药性.
- 了解S. pseudintermedius抗生素耐药性的遗传基础对于动物健康和食品安全至关重要.
相关概念视频
Production of Antibiotics
285
Penicillin, one of the earliest and most widely used antibiotics, is produced industrially by the filamentous fungus Penicillium chrysogenum. Large stirred-tank bioreactors ranging from tens to hundreds of thousands of liters maintain tightly controlled temperature, pH, and dissolved oxygen conditions to support fungal metabolism and maximize antibiotic yield. Penicillin is a secondary metabolite, synthesized primarily during the stationary growth phase, which requires a carefully managed...
285
Production of Pharmaceuticals
100
Industrial insulin production uses genetically engineered E. coli expressing a proinsulin gene controlled by a tryptophan promoter and containing a methionine linker for later cleavage. The cells also carry ampicillin resistance for selective growth. Seed cultures are stored at −80 °C and production begins by thawing a small amount to inoculate starter cultures, which are progressively scaled to a 50,000-L bioreactor. In the bioreactor, E. coli grow in nutrient-rich media under...
100
Mechanism of Antibiotic Resistance in MRSA
251
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...
251
Clinical Significance of Antibiotic Resistance
115
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...
115


