Klis Frans M, Sosinska Grazyna J, de Groot Piet W J, Brul Stanley
Swammerdam Institute for Life Sciences, University of Amsterdam, 1018 WV Amsterdam, The Netherlands.
FEMS Yeast Res. 2009 Oct;9(7):1013-28. doi: 10.1111/j.1567-1364.2009.00541.x. Epub 2009 Jun 22.
The cell wall of Candida albicans consists of an internal skeletal layer and an external protein coat. This coat has a mosaic-like nature, containing c. 20 different protein species covalently linked to the skeletal layer. Most of them are GPI proteins. Coat proteins vary widely in function. Many of them are involved in the primary interactions between C. albicans and the host and mediate adhesive steps or invasion of host cells. Others are involved in biofilm formation and cell-cell aggregation. They further include iron acquisition proteins, superoxide dismutases, and yapsin-like aspartic proteases. In addition, several covalently linked carbohydrate-active enzymes are present, whose precise functions remain hitherto largely elusive. The expression levels of the genes that encode covalently linked cell wall proteins (CWPs) can vary enormously. They depend on the mode of growth and the combined inputs of several signaling pathways that sense environmental conditions. This is reflected in the unusually long intergenic regions of most of these genes. Finally, the precise location of several covalently linked CWPs is temporally and spatially regulated. We conclude that covalently linked CWPs of C. albicans play a crucial role in fitness and virulence and that their expression is tightly controlled.
白色念珠菌的细胞壁由一个内部骨架层和一个外部蛋白质外壳组成。这个外壳具有马赛克样的性质，包含约20种不同的蛋白质，它们与骨架层共价连接。其中大多数是糖基磷脂酰肌醇（GPI）蛋白。外壳蛋白的功能差异很大。它们中的许多参与白色念珠菌与宿主之间的初始相互作用，并介导黏附步骤或宿主细胞的侵袭。其他的则参与生物膜形成和细胞间聚集。它们还包括铁摄取蛋白、超氧化物歧化酶和类天冬氨酸蛋白酶。此外，还存在几种共价连接的碳水化合物活性酶，其确切功能迄今仍大多不清楚。编码共价连接的细胞壁蛋白（CWP）的基因表达水平可能有很大差异。它们取决于生长模式以及感知环境条件的几种信号通路的综合输入。这在这些基因大多数异常长的基因间隔区中得到体现。最后，几种共价连接的CWP的精确位置在时间和空间上受到调控。我们得出结论，白色念珠菌的共价连接CWP在适应性和毒力中起关键作用，并且它们的表达受到严格控制。
