ANIONIC LIPIDS ENRICHED AT THE EXPORTAL OF STREPTOCOCCUS PYOGENES

这个子项目是许多研究子项目中的一个 由NIH/NCRR资助的中心赠款提供的资源。子项目和 研究者（PI）可能从另一个NIH来源获得了主要资金， 因此可以在其他CRISP条目中表示。所列机构为 研究中心，而研究中心不一定是研究者所在的机构。 化脓性链球菌的ExPortal是一个专门用于蛋白质分泌和折叠的膜微结构域。我们通过检查阴离子膜磷脂的分布研究了ExPortal的脂质组成。用10-N-壬基-吖啶橙子染色揭示了富含阴离子磷脂的单个微区，其在心磷脂缺陷突变体中的染色特征和行为是磷脂酰甘油的特征。此外，微结构域的位置对应于在ExPortal的活性蛋白分泌的位点。这些结果表明，ExPortal是一个不对称的脂质微区，其丰富的阴离子磷脂含量可能在ExPortal组织和蛋白质运输中发挥重要作用。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The ExPortal of Streptococcus pyogenes is a membrane microdomain dedicated to the secretion and folding of proteins. We investigated the lipid composition of the ExPortal by examining the distribution of anionic membrane phospholipids. Staining with 10-N-nonyl-acridine orange revealed a single microdomain enriched with an anionic phospholipid whose staining characteristics and behavior in a cardiolipin-deficient mutant were characteristic of phosphatidylglycerol. Furthermore, the location of the microdomain corresponded to the site of active protein secretion at the ExPortal. These results indicate that the ExPortal is an asymmetric lipid microdomain, whose enriched content of anionic phospholipids may play an important role in ExPortal organization and protein trafficking.