O'Gara James P
School of Biomolecular and Biomedical Science, Ardmore House, University College Dublin, Belfield, Dublin, Ireland.
FEMS Microbiol Lett. 2007 May;270(2):179-88. doi: 10.1111/j.1574-6968.2007.00688.x. Epub 2007 Apr 10.
Recent progress in elucidating the role of the icaADBC-encoded polysaccharide intercellular adhesin (PIA) or polymeric N-acetyl-glucosamine (PNAG) in staphylococcal biofilm development has in turn contributed significantly to our understanding of the pathogenesis of device-related infections. Nevertheless, our understanding of how the ica locus and PIA/PNAG biosynthesis are regulated is far from complete and many questions remain. Moreover, beyond ica, evidence is now emerging for the existence of ica-independent biofilm mechanisms in both Staphylococcus aureus and Staphylococcus epidermidis. Teichoic acids, which are a major carbohydrate component of the S. epidermidis biofilm matrix and the major cell wall autolysin, play an important role in the primary attachment phase of biofilm development, whereas the cell surface biofilm-associated protein and accumulation-associated protein are capable of mediating intercellular accumulation. These findings raise the exciting prospect that other surface proteins, which typically function as antigenic determinants or in binding to extracellular matrix proteins, may also act as biofilm adhesins. Given the impressive array of surface proteins expressed by S. aureus and S. epidermidis, future research into their potential role in biofilm development either independent of PIA/PNAG or in cooperation with PIA/PNAG will be of particular interest.
在阐明icaADBC编码的胞间多糖黏附素(PIA)或聚合N-乙酰葡糖胺(PNAG)在葡萄球菌生物膜形成中的作用方面的最新进展,反过来又极大地促进了我们对与器械相关感染发病机制的理解。然而,我们对ica基因座以及PIA/PNAG生物合成如何调控的理解还远远不够完整,仍存在许多问题。此外,除了ica之外,现在有证据表明金黄色葡萄球菌和表皮葡萄球菌中存在不依赖ica的生物膜形成机制。磷壁酸是表皮葡萄球菌生物膜基质的主要碳水化合物成分以及主要的细胞壁自溶素,在生物膜形成的初始黏附阶段发挥重要作用,而细胞表面生物膜相关蛋白和积累相关蛋白能够介导细胞间积累。这些发现带来了一个令人兴奋的前景,即其他通常作为抗原决定簇或与细胞外基质蛋白结合发挥作用的表面蛋白,也可能充当生物膜黏附素。鉴于金黄色葡萄球菌和表皮葡萄球菌表达的表面蛋白种类繁多,未来对它们在不依赖PIA/PNAG或与PIA/PNAG协同作用下在生物膜形成中潜在作用的研究将特别有趣。