Disruption of the tagF Orthologue in the epa Locus Variable Region of Enterococcus faecalis Causes Cell Surface Changes and Suppresses an eep-Dependent Lysozyme Resistance Phenotype.
Disruption of the tagF Orthologue in the epa Locus Variable Region of Enterococcus faecalis Causes Cell Surface Changes and Suppresses an eep-Dependent Lysozyme Resistance Phenotype.
复制标题
粪肠球菌 epa 基因座可变区 tagF 直系同源物的破坏导致细胞表面变化并抑制 eep 依赖性溶菌酶抗性表型。
DOI：
10.1128/jb.00247-22
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发表时间：
2022
影响因子：
3.2
通讯作者：
Frank,KristiL
中科院分区：
文献类型：
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作者：
Rouchon,CandaceN;Weinstein,ArielleJ;Hutchison,CarissaA;Zubair-Nizami,ZahraB;Kohler,PetraL;Frank,KristiL
机会致病菌粪肠球菌的致病能力因其逃避抗菌剂杀灭的能力而增强。E的生存。在存在人抗微生物酶溶菌酶的情况下，肠球菌对粪肠球菌的耐药性部分由位点2金属蛋白酶Eep介导;然而，尚未阐明肠球菌溶菌酶耐药性的完整模型。为了更好地了解大肠杆菌耐溶菌酶的分子基础。粪肠球菌中，我们分析了Δ epsuppressor突变体，这些突变体通过基因OG1RF_11713突变获得对溶菌酶的抗性，OG1RF_11713是一个位于肠球菌多糖抗原（epa）基因座可变区内的预测磷壁酸生物合成编码基因。序列比较显示，OG1RF_11713与表皮葡萄球菌胞苷二磷酸甘油：聚甘油磷酸转移酶TagF基因同源性最高。在野生型和Δeepgenetic背景下，OG1RF_11713的失活足以增加E. faecalis OG 1 RF转化为溶菌酶。在OG1RF_11713缺失突变体的细胞壁碳水化合物提取物中可检测到极少量的N-乙酰半乳糖胺，这与细胞表面负电荷的减少有关。OG1RF_11713的靶向破坏也与对抗生素多粘菌素B和膜靶向洗涤剂的敏感性增加以及对羊毛硫抗生素乳链菌肽的敏感性降低有关。这项工作implicatesOG1RF_11713作为一个主要的决定因素的细胞包膜的完整性，并提供了进一步的验证，溶菌酶的耐药性是内在联系的修改肠球菌细胞壁polysaccharides.IMPORTANCEEnterococcus faecalis是一个主要的原因，医疗保健相关的感染，有有限的治疗方案。E.粪肠球菌对几种抗生素和高浓度的人类抗微生物酶溶菌酶具有抗性。对大肠杆菌溶菌酶抗性的分子机制进行了初步探讨。粪便是复杂的，并且仍然不完全表征。这项工作表明，一个基因位于可变区的肠球菌多糖抗原基因座的E。粪球菌菌株OG 1 RF（OG1RF_11713），其被预测为编码磷壁酸生物合成机制的组分，是溶菌酶抗性回路的一部分，并且对于肠球菌细胞壁完整性是重要的。这些发现表明OG1RF_11713是对抗肠球菌感染的新治疗策略的潜在靶点。
The disease-producing capacity of the opportunistic pathogen Enterococcus faecalis is enhanced by the ability of the bacterium to evade killing by antimicrobial agents. Survival of E. faecalis in the presence of the human antimicrobial enzyme lysozyme is mediated in part by the site 2 metalloprotease Eep; however, a complete model of enterococcal lysozyme resistance has not been elucidated. To better understand the molecular basis for lysozyme resistance in E. faecalis, we analyzed Δeepsuppressor mutants that acquire resistance to lysozyme through mutation of the geneOG1RF_11713, a predicted teichoic acid biosynthesis-encoding gene located within the variable region of the enterococcal polysaccharide antigen (epa) locus. Sequence comparisons revealed thatOG1RF_11713is most similar to the cytidine-5′-diphosphate (CDP)-glycerol:poly-(glycerolphosphate)glycerophosphotransferase TagF from Staphylococcus epidermidis. Inactivation ofOG1RF_11713in both the wild-type and Δeepgenetic backgrounds was sufficient to increase the resistance of E. faecalis OG1RF to lysozyme. Minimal amounts ofN-acetylgalactosamine were detectable in cell wall carbohydrate extracts ofOG1RF_11713deletion mutants, and this was associated with a reduction in negative cell surface charge. Targeted disruption ofOG1RF_11713was also associated with increased susceptibility to the antibiotic polymyxin B and membrane-targeting detergents and decreased susceptibility to the lantibiotic nisin. This work implicatesOG1RF_11713as a major determinant of cell envelope integrity and provides further validation that lysozyme resistance is intrinsically linked to the modification of enterococcal cell wall polysaccharides.IMPORTANCEEnterococcus faecalis is a leading cause of health-care-associated infections for which there are limited treatment options. E. faecalis is resistant to several antibiotics and to high concentrations of the human antimicrobial enzyme lysozyme. The molecular mechanisms that mediate lysozyme resistance in E. faecalis are complex and remain incompletely characterized. This work demonstrates that a gene located within the variable region of the enterococcal polysaccharide antigen locus of E. faecalis strain OG1RF (OG1RF_11713), which is predicted to encode a component of the teichoic acid biosynthesis machinery, is part of the lysozyme resistance circuitry and is important for enterococcal cell wall integrity. These findings suggest thatOG1RF_11713is a potential target for new therapeutic strategies to combat enterococcal infections.