Ruiz-Herrera José, Martínez Ana I, Sentandreu Rafael
Departamento de Ingeniería Genética, Centro de Investigacíon y Estudios Avanzados del Instituto Politécnico Nacional, Irapuato, Gto, Mexico.
Res Microbiol. 2002 Jul-Aug;153(6):373-8. doi: 10.1016/s0923-2508(02)01335-9.
Stability of the protein populations present in the cell wall of three ascomycetous fungi Candida albicans, Saccharomyces cerevisiae and Yarrowia lipolytica was investigated. Cell wall proteins were either labeled with biotin or radiolabeled with amino acids, and chased for a period of time representing several generations. Proteins linked by non-covalent or covalent bonds were separated and their turnover was analyzed. No significant turnover took place during the chase period, and in fact radioactive proteins were accumulated in the wall during the period possibly by transfer through the secretory pathway. This transfer did not involve de novo protein synthesis; it was inhibited by azide, and by incubation of a sec1 mutant of S. cerevisiae at the non-permissive temperature. It is concluded that proteins bound to the cell wall are stable and that there is no precursor-product relationship among those linked by non-covalent bonds and the covalently bound ones.
研究了三种子囊菌白色念珠菌、酿酒酵母和解脂耶氏酵母细胞壁中蛋白质群体的稳定性。细胞壁蛋白用生物素标记或用氨基酸进行放射性标记，并追踪代表几代的一段时间。通过非共价键或共价键连接的蛋白质被分离，并分析其周转情况。在追踪期间没有发生显著的周转，事实上放射性蛋白质在这段时间内可能通过分泌途径转移而在细胞壁中积累。这种转移不涉及从头合成蛋白质；它受到叠氮化物以及酿酒酵母sec1突变体在非允许温度下孵育的抑制。得出的结论是，与细胞壁结合的蛋白质是稳定的，并且通过非共价键连接的蛋白质与共价结合的蛋白质之间不存在前体-产物关系。
