Adherence and receptor relationships of Candida albicans.
Adherence and receptor relationships of Candida albicans.
复制标题
白色念珠菌的粘附和受体关系。
DOI：
10.1128/mr.55.1.1-20.1991
复制
发表时间：
1991
期刊：
影响因子：
--
通讯作者：
Braun,PC
中科院分区：
文献类型：
--
作者：
Calderone,RA;Braun,PC
白色念珠菌的细胞表面由葡聚糖、几丁质、甘露聚糖等多种多糖组成。前两个组分主要提供结构，而甘露聚糖通常与蛋白质共价连接，构成有机体的主要抗原。甘露糖蛋白还具有酶活性(酸性蛋白酶)和配体受体功能。白念珠菌的补体受体似乎是生物体与内皮细胞黏附所必需的甘露糖蛋白。白念珠菌中类似CR3的蛋白当然也是如此。CR3是内皮细胞的念珠菌受体的证据来自两个观察。首先，缺乏CR3活性的突变体在体外的粘附性较差，事实上，毒力也较低。其次，CR3受体(C3bi)识别的配体以及抗CR3抗体阻止了生物体与内皮细胞的粘连。白色念珠菌的CR2似乎促进了有机体对塑料基质的黏附。与哺乳动物细胞的CR2不同，念珠菌CR2除了识别不含RGD序列的C3d配体外，还识别含有RGD序列的氨基酸配体。假丝酵母菌CR2和CR3是否实际上是不同的蛋白质还不确定。一种甘露糖蛋白也被描述为上皮细胞的粘附素。在这种情况下，受体具有凝集素样的活性，识别上皮细胞中含有岩藻糖或氨基葡萄糖的糖蛋白，这取决于白念珠菌的菌株。受体的寡糖成分可能不参与配基识别，并可能起到稳定受体的作用。然而，甘露聚糖的寡糖因子6表位也可能在识别上皮细胞中提供粘附素活性。甘露糖蛋白可以通过多种试剂从细胞中提取出来。例如，发酵酶倾向于去除结构性甘露糖蛋白，甘露糖蛋白含有相对较少的蛋白质，并与葡聚糖相连。另一方面，二硫苏糖醇等试剂倾向于提取含有较高蛋白的甘露糖蛋白，这些蛋白似乎具有受体功能。白念珠菌的甘露糖蛋白是动态表达的，可能是生长阶段和生长形式特有的。
The cell surface of Candida albicans is composed of a variety of polysaccharides such as glucan, chitin, and mannan. The first two components primarily provide structure, while the mannan, often covalently linked to protein, constitutes the major antigen of the organism. Mannoproteins also have enzymatic activity (acid protease) and ligand-receptor functions. The complement receptors of C. albicans appear to be mannoproteins that are required for the adherence of the organism to endothelial cells. This is certainly true of the CR3-like protein of C. albicans. Proof that the CR3 is the Candida receptor for endothelial cells is derived from two observations. First, mutants lacking CR3 activity are less adherent in vitro and, in fact, less virulent. Second, the ligand recognized by the CR3 receptor (C3bi) as well as anti-CR3 antibodies blocks adherence of the organism to endothelial cells. The CR2 of C. albicans appears to promote the adherence of the organism to plastic substrates. Unlike the CR2 of mammalian cells, the Candida CR2 recognizes ligands containing the RGD sequence of amino acids in addition to the C3d ligand, which does not contain the RGD sequence. There is uncertainty as to whether the Candida CR2 and CR3 are, in fact, different proteins. A mannoprotein has also been described as the adhesin for epithelial cells. In this case, the receptor has a lectinlike activity and recognizes fucose- or glucosamine-containing glycoproteins of epithelial cells, depending on the strain of C. albicans. The oligosaccharide component of the receptor is probably not involved in ligand recognition and may serve to stabilize the receptor. However, the oligosaccharide factor 6 epitope of mannan may also provide adhesin activity in the recognition of epithelial cells. Mannoproteins can be extracted from cells by a number of reagents. Zymolyase, for instance, tends to remove structural mannoproteins, which contain relatively little protein and are linked to glucan. Reagents such as dithiothreitol, on the other hand, tend to extract mannoproteins containing higher amounts of protein that appear to have receptor function. The mannoproteins of C. albicans are dynamically expressed and may be growth phase and growth form specific.