Sulter G J, Vrieling E G, Harder W, Veenhuis M
Department of Microbiology, University of Groningen, Haren, The Netherlands.
EMBO J. 1993 May;12(5):2205-10. doi: 10.1002/j.1460-2075.1993.tb05868.x.
We have studied the synthesis and subcellular location of peroxisomal membrane proteins (PMPs) in cells of a peroxisome-deficient (per) mutant of the methylotrophic yeast Hansenula polymorpha. Western blot analysis of methanol-induced cells of the per mutant, which had been growing in a continuous culture on a glucose/methanol mixture, indicated that various PMPs were normally synthesized. As in wild type (WT) cells, the levels of PMP synthesis appeared to be dependent on specific cultivation conditions, e.g. the carbon source used for growth. In contrast to WT controls, PMPs in methanol-induced per mutants were not subject to proteolytic degradation. Biochemical and immuno(cyto)chemical studies suggested that the PMPs in methanol-induced per cells were located in small proteinaceous aggregates, separated from peroxisomal matrix proteins that were also present in the cytosol. Vesicular membranous structures, resembling the morphology of intact peroxisomes, were never detected irrespective of the growth conditions employed.
我们研究了多形汉逊酵母过氧化物酶体缺陷型（per）突变体细胞中过氧化物酶体膜蛋白（PMPs）的合成及亚细胞定位。对在葡萄糖/甲醇混合物中连续培养的per突变体甲醇诱导细胞进行蛋白质免疫印迹分析表明，各种PMPs正常合成。与野生型（WT）细胞一样，PMPs的合成水平似乎取决于特定的培养条件，例如用于生长的碳源。与WT对照不同，甲醇诱导的per突变体中的PMPs不受蛋白水解降解作用。生化和免疫（细胞）化学研究表明，甲醇诱导的per细胞中的PMPs位于小的蛋白质聚集体中，与也存在于细胞质中的过氧化物酶体基质蛋白分开。无论采用何种生长条件，均未检测到类似完整过氧化物酶体形态的囊泡膜结构。
