提高酵母精呈味特性和得率的研究

研究结果表明:以13～15%的酵母悬浮液,外加干酵母重1. 0%的蛋白酶及0. 1%的乙酸和半胱氨酸,调节 pH6. 2～6. 4,在40MPa 压力下均质三次,然后在48℃自溶24h,自溶完后抽提出来未降解的 RNA,外加11. 0%麦芽根提取的5′-磷酸二酯酶粗酶液在 pH5. 5.65℃恒温3h,定向地将RNA 分解为5′-核苷酸,得到的酵母精具有浓郁的鲜香味,不带酵母味,且得率比对照提高48. 3%,达75. 5%;氨基氮提高40. 5%,达5. 9%;5′-GMP 含量提高20. 6倍,含量1. 65%;自溶时间缩短三分之一。     

用啤酒酵母试制代可可粉及可可风味饮料的研究

用啤酒厂酵母泥为主要原料，研究以小试规模生产代可可粉的生产工艺，以及用代可可粉调制可可风味饮料的配方。重点研究用化学试剂组合脱酵母臭的方法，研究制出与天然可可粉质地、大小、色泽和风味相似的代可可粉。     

PAS domain of the deduced Org35 protein mediates the interaction with NifA

PAS domains are sensory input domains and pro- tein-protein interaction sites that have been identified recently in a family of sensory proteins from all king-doms of life[1,2]. A variety of environmental stimuli such as light, oxygen, redox potential, an…     

面包酵母非水相催化乙酰乙酸乙酯的不对称还原反应

利用面包酵母在非水相中不对称还原乙酰乙酸乙酯，制备了光学活性的手性化合物（S）-3-羟基丁酸乙酯。通过转化率和e,e,值筛选了lgP（lgP为正辛醇-水体系中的油水分配系数）值不同的有机溶剂，并考察了反应体系中水含量对生物催化乙酰乙酸乙酯不对称还原反应的影响。结果表明：lgP〉2．0的有机溶剂，可以选用作为面包酵母催化的反应介质，其中以正己烷较为合适；且反应的最佳水含量为19．2％（V水／V有机溶剂）。     

ITN4-C相互作用蛋白的筛选与鉴定

我们的前期工作发现过表达RTN4-C基因能够抑制肝癌细胞株SMMC7721的生长并且促进其发生凋亡．为了进一步了解RTN4-C促进凋亡的机制，本文采用酵母双杂交的方法从小鼠7d胚胎文库中筛选其相互作用的蛋白．最终筛选到其同源家族成员RTN3．进一步采用间接免疫荧光和及构建的荧光载体表明，RTN4-C和RTN3蛋白在HEK293和Hela细胞中发生共分布．本研究为进一步阐明RTN4-C抑制细胞生长和促进细胞凋亡的机制提供了新的依据．     

人染色体17q12区雨330kb范围内表达顺序的筛选

用定位于人染色体17q12区带的长约330kbYAC克隆500D09（取自法国人类多态性研究中心YAC库）作为杂交探针，筛选人骨髓、胎脑、胎肾、骨骼肌和睾丸等五种组织的cDNA库（2×105～3×105pfu／库），从中获得102个初级阳性克隆．初级克隆经PCR扩增，分别与人基因组DNA、酵母基因组DNA和人rDNA探针作dotblot杂交分析，排除其中假阳性克隆后，复筛得到32个候选克隆．对其中2个候选克隆B4511和S5511分别测定143bp和147bp序列．经查新和同源性分析，这两个片段与已知基因的同源性均小于50％，提示它们可能是来自于新基因的表达顺序．     

Analysis of correlations between protein complex and protein-protein interaction and mRNA expression

Protein-protein interaction is a physical interaction of two proteins in living cells. In budding yeast Saccharomyces cerevisiae, large-seale protein-protein interaction data have been obtained through high-throughput yeast two-hybrid systems (Y2H) and protein complex purification techniques based on mass-spectrometry. Here, we collect 11855 interactions between total 2617 proteins. Through seriate genome-wide mRNA expression data, similarity between two genes could be measured. Protein complex data can also be obtained publicly and can be translated to pair relationship that any two proteins can only exist in the same complex or not. Analysis of protein complex data, protein-protein interaction data and mRNA expression data can elucidate correlations between them. The results show that proteins that have interactions or similar expression patterns have a higher possibility to be in the same protein complex than randomized selected proteins, and proteins which have interactions and similar expression patterns are even more possible to exist in the same protein complex. The work indirates that comprehensive integration and analysis of public large-seale bioinformatical data, such as protein complex data, protein-protein interaction data and mRNA expression data, may help to uncover their relationships and common biological information underlying these data. The strategies described here may help to integrate and analyze other functional genomic and proteomic data, such as gene expression profiling, protein-localization mapping and large-scale phenotypic data, both in yeast and in other organisms.     

Z3, a novel antisense snoRNA fromSaccharomyces cerevisiae

Small nucleolar RNA (snoRNA) is one of the most important elements participating in eukaryotic ribosomal biogenesis. The present report describes the results of the identification of a novel snoRNA, Z3, from yeast S. cerevisiae. Z3 snoRNA is 106 nts in length. It contains box C, D elements and a 13 nt complementarity to 25S rRNA. This antisense segment, together with the downstream box D, guides a 2′-O-ribose methylation of cytidine acid at position 2956th in yeast 25 S rRNA. Z3 snoRNA, encoded by an independent transcribed gene on the chromosome  of yeast, possesses the same functional elements responsible for the rRNA methylation site as that of the intron-encoded U35 snoRNA of vertebrate.     

云南大围山自然保护区山地雨林中的酵母菌种群多样性的初步研究

云南大围山自然保护区山地雨林植被下土壤酵母菌的数量及种群多样性．从大围山采集的８个样点分离到１３１株酵母菌,分类鉴定为６属５种：隐球酵母属（Ｃｒｙｐｔｏｃｏｃｕｓ）３个种,３３株;德巴利酵母属（Ｄｅｂａｒｙｏｍｙｃｅｓ）１个种,１９株;假丝酵母属（Ｃａｎｄｉｄａ）,毕赤酵母属（Ｐｉｃｈｉａ）１个种,１株;锁掷孢酵母属（ｓｐｏｒｉｄｉｏｂｏｌｕｓ）;拟威尔酵母属（Ｗｉｌｉｏｐｓｉｓ）．未定到属的１０株,鉴定到种的５３株,占总菌株数的４０４６％．该地区的种群多样性表现为隐球酵母属在数量占优势,假丝酵母属分布广的特点．