Muthukumar G, Suhng S H, Magee P T, Jewell R D, Primerano D A
Department of Methods Development and Scale-Up, Enzon, Inc., Piscataway, New Jersey 08854-3998.
J Bacteriol. 1993 Jan;175(2):386-94. doi: 10.1128/jb.175.2.386-394.1993.
A number of genes have been shown to be transcribed specifically during sporulation in Saccharomyces cerevisiae, yet their developmental function is unknown. The SPR1 gene is transcribed during only the late stages of sporulation. We have sequenced the SPR1 gene and found that it has extensive DNA and protein sequence homology to the S. cerevisiae EXG1 gene which encodes an exo-1,3-beta-glucanase expressed during vegetative growth (C. R. Vasquez de Aldana, J. Correa, P. San Segundo, A. Bueno, A. R. Nebrada, E. Mendez, and F. del Ray, Gene 97:173-182, 1991). We show that spr1 mutant cells do not hydrolyze p-nitrophenyl-beta-D-glucoside or laminarin in a whole-cell assay for exo-1,3-beta-glucanases. In addition to the absence of this enzymatic activity, spr1 mutant spores exhibit reduced thermoresistance relative to isogenic wild-type spores. These observations are consistent with the notion that SPR1 encodes a sporulation-specific exo-1,3-beta-glucanase.
已证明许多基因在酿酒酵母的孢子形成过程中特异性转录，但其发育功能尚不清楚。SPR1基因仅在孢子形成后期转录。我们对SPR1基因进行了测序，发现它与酿酒酵母EXG1基因具有广泛的DNA和蛋白质序列同源性，EXG1基因编码一种在营养生长期间表达的外切1,3-β-葡聚糖酶（C.R. Vasquez de Aldana、J. Correa、P. San Segundo、A. Bueno、A.R. Nebrada、E. Mendez和F. del Ray，《基因》97:173 - 182，1991）。我们表明，在全细胞外切1,3-β-葡聚糖酶检测中，spr1突变细胞不能水解对硝基苯基-β-D-葡糖苷或海带多糖。除了缺乏这种酶活性外，spr1突变孢子相对于同基因野生型孢子表现出降低的耐热性。这些观察结果与SPR1编码一种孢子形成特异性外切1,3-β-葡聚糖酶的观点一致。
