de Nobel J G, Klis F M, Priem J, Munnik T, van den Ende H
Department of Molecular Cell Biology, University of Amsterdam, The Netherlands.
Yeast. 1990 Nov-Dec;6(6):491-9. doi: 10.1002/yea.320060606.
The cell wall porosity of batch-grown Saccharomyces cerevisiae was maximal in the early exponential phase and fell off rapidly to lower levels in later growth phases. Treatment of stationary-phase cells with alpha-mannosidase restored wall porosity to the level of cells in early exponential phase. When cells in the early exponential phase were treated with alpha-mannosidase, or tunicamycin, an inhibitor of N-glycosylation, even higher porosities were obtained. Mutants with truncated mannan side-chains in their wall proteins also had very porous walls. The importance of the mannan side-chains for wall porosity was also seen during sexual induction. Treatment with alpha pheromone, which leads to the formation of wall proteins with shorter mannan side-chains, enhanced wall porosity. Disulphide bridges also affect cell wall porosity. They were predominantly found in the glucanase-soluble wall proteins. Because the main part of the mannan side-chains is also found in this family of wall proteins, our results demonstrate that the glucanase-soluble mannoproteins limit cell wall porosity in yeast.
分批培养的酿酒酵母的细胞壁孔隙率在指数生长早期最大，在后期生长阶段迅速下降至较低水平。用α-甘露糖苷酶处理稳定期细胞可使细胞壁孔隙率恢复到指数生长早期细胞的水平。当用α-甘露糖苷酶或衣霉素（一种N-糖基化抑制剂）处理指数生长早期的细胞时，可获得更高的孔隙率。细胞壁蛋白中甘露聚糖侧链截短的突变体也具有非常多孔的细胞壁。在有性诱导过程中也可以看出甘露聚糖侧链对细胞壁孔隙率的重要性。用α因子处理会导致形成具有较短甘露聚糖侧链的细胞壁蛋白，从而增加细胞壁孔隙率。二硫键也会影响细胞壁孔隙率。它们主要存在于葡聚糖酶可溶的细胞壁蛋白中。由于甘露聚糖侧链的主要部分也存在于这一族细胞壁蛋白中，我们的结果表明，葡聚糖酶可溶的甘露糖蛋白限制了酵母细胞壁的孔隙率。
