N-Acylhomoserine lactones (AHLs) are used as quorum-sensing signals in Gram-negative bacteria. Many genes encoding AHL-degrading enzymes have been cloned and characterized in various microorganisms. Coagulase-negative staphylococci (CNS) are present on the skin of animals and are considered low-virulent species. The AHL-lactonase gene homologue, ahlS, was present in the genomes of the CNS strains Staphylococcus carnosus, Staphylococcus haemolyticus, Staphylococcus saprophyticus, and Staphylococcus sciuri. We cloned the candidate ahlS homologue from six CNS strains into the pBBR1MCS5 vector. AhlS from the CNS strains showed a higher degrading activity against AHLs with short acyl chains compared to those with long acyl chains. AhlS from S. sciuri was expressed and purified as a maltose-binding protein (MBP) fusion. Pseudomonas aeruginosa is an opportunistic pathogen that regulates several virulence factors such as elastase and pyocyanin by quorum-sensing systems. When MBP-AhlS was added to the culture of P. aeruginosa PAO1, pyocyanin production and elastase activity were substantially reduced compared to those in untreated PAO1. These results demonstrate that the AHL-degrading activity of AhlS from the CNS strains can inhibit quorum sensing in P. aeruginosa PAO1.

中文翻译：

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凝固酶阴性葡萄球菌N-酰基高丝氨酸纤维素酶的猝灭猝灭活性的鉴定与表征。

N-酰基高丝氨酸内酯（AHLs）在革兰氏阴性细菌中用作群体感应信号。已经在多种微生物中克隆并表征了许多编码AHL降解酶的基因。凝固酶阴性葡萄球菌（CNS）存在于动物皮肤上，被认为是低毒种。的AHL-内酯酶基因同源物，信号分子，是存在于CNS中的菌株的基因组肉葡萄球菌，溶血葡萄球菌，腐生葡萄球菌，和葡萄球菌松鼠葡萄球菌。我们克隆了候选ahlS六个CNS菌株的同系物进入pBBR1MCS5载体。与具有长酰基链的那些相比，来自CNS菌株的AhlS对具有短酰基链的AHL显示出更高的降解活性。表达和纯化来自麦芽糖链球菌的AhlS，为麦芽糖结合蛋白（MBP）融合体。铜绿假单胞菌是机会病原体，其通过群体感应系统调节几种毒力因子，例如弹性蛋白酶和绿脓素。当将MBP-AhlS添加到铜绿假单胞菌PAO1的培养物中时，与未处理的PAO1相比，绿脓素的产生和弹性蛋白酶的活性大大降低。这些结果表明，来自CNS菌株的AhlS的AHL降解活性可以抑制铜绿假单胞菌PAO1中的群体感应。