Purification and characterization of the inducible a agglutinin of Saccharomyces cerevisiae.
Purification and characterization of the inducible a agglutinin of Saccharomyces cerevisiae.
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酿酒酵母诱导型α凝集素的纯化和表征。
DOI：
10.1002/j.1460-2075.1988.tb02966.x
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发表时间：
1988
期刊：
影响因子：
--
通讯作者：
Tanner
中科院分区：
文献类型：
--
作者：
M. Watzele;F. Klis;Widmar;Tanner
酿酒酵母a细胞中由交配信息素α因子诱导的细胞表面糖蛋白已纯化为均一。在4×10(-9)M时，它强烈抑制α细胞和α细胞之间的交配型特异性凝集。这种蛋白质完全是O-糖基化的。它由29%的碳水化合物组成，在十二烷基硫酸钠凝胶上的表观分子质量为22kd。经过HF处理后，它的行为就像一个13kd的蛋白质；因此，它的真实分子质量可能接近18kd。温和的高碘酸盐处理会破坏纯化蛋白的生物活性。该蛋白质含有一个半胱氨酸，不含精氨酸，27%的氨基酸是丝氨酸和苏氨酸残基，其中三分之二是糖基化的。利用多克隆抗体，在信息素加入15分钟后，即可在细胞表面检测到糖蛋白。诱导抗原不在细胞周期的特定阶段表达；它首先只出现在生长的芽中。母细胞只有在子细胞分离后才会在其表面表达抗原；然后它被定位在梨形“shmoo”的尖端。使用分泌型ts突变体SEC 18表明，凝集素的甘露糖化前体聚集在内质网上。
A cell surface glycoprotein induced by the mating pheromone alpha factor in Saccharomyces cerevisiae a cells has been purified to homogeneity. At 4 x 10(‐9) M it strongly inhibits mating‐type‐specific agglutination between a and alpha cells. The protein is solely O‐glycosylated. It consists of 29% carbohydrate and its apparent molecular mass is 22 kd on SDS gels. After HF treatment it behaves like a protein of 13 kd; therefore its true molecular mass probably is close to 18 kd. Mild periodate treatment destroys the biological activity of the purified protein. The protein contains one cysteine, no arginine, and 27% of the amino acids are serine and threonine residues, two thirds of which are glycosylated. With a polyclonal antibody the glycoprotein can already be detected at the cell surface 15 min after pheromone addition. The inducible antigen is not expressed in a specific phase of the cell cycle; it first appears exclusively on the growing bud. Mother cells express the antigen on their surface only after the daughter cells have separated; it is then localized at the tip of the pear‐shaped ‘shmoo’. Using the secretory ts‐mutant sec 18 is shown that a mannosylated precursor of a agglutinin accumulates at the endoplasmic reticulum.