During the process of wheat Qu-making, a series of metabolic reactions originated from microorganisms inoculated naturally occur to provide various enzymes and flavour compounds precursors for fermentation of Shaoxing Rice Wine. According to metaproteomics, two-dimensional electrophoresis （2-DE） and tandem mass spectrometry （MS/MS） methods were used to analyze the extracts of ＂wheat Qu＂ during the six making-stages （including starting period, early-fermentation period, warming period, high-temperature period, cooling period and mature period）. By comparative analysis of the 2-DE maps by using the PDQuest software, 12 spots with dramatic variations of expression level were found and subsequently identified by MALDI-TOF/TOF MS. Among the 7 protein spots which were identi- fied successfully, there were 4 spots from microbes, including the coagulation factor with 5/8 type domain protein （Amycolatopsis mediterranei U32）, the malate dehydrogenase （Micromons sp. RCC299）, carboxypeptidase T precursor and glucose-6-phosphate isomerase （Saccharopolyspora erythraea NRRL 2338）. The other 3 protein spots were the hypothetical protein （Ectocarpus siliculosus）, xylanase inhibitor protein and class II chitinase （Triticum aestivum）.%麦曲在制曲的过程中,以小麦为原料,通过自然接种环境中的微生物,发生一系列的生物化学变化,最终生成黄酒酿造所需的各种粗酶制剂以及风味代谢物质的前体。该研究利用宏蛋白质组学的理论和方法,对绍兴黄酒麦曲制曲过程中6个不同时期（起始期、发酵前期、升温期、高温期、降温期、成熟期）的麦曲浸提液宏蛋白质组进行双向电泳实验,研究麦曲制曲过程中浸提液宏蛋白质组的变化情况。使用PDQuest软件对获得的双向电泳图谱进行比较分析,发现共有12个蛋白点在制曲过程中发生了动态变化。利用基质辅助激光解吸/电离飞行时间串联质谱（MALDI-TOF/TOF MS）对该12个差异蛋白点进行了质谱分析,其中7个鉴定成功,分别是来自一种稀有细菌的凝结因子5/8型功能蛋白,微单孢菌属的苹果酸脱氢酶,糖红孢红霉菌的葡萄糖-6-磷酸异构酶和羧肽酶前体蛋白,外子藻的功能未知蛋白以及小麦的木聚糖酶抑制剂和几丁质酶。
展开▼
