核桃JrHSP20-1基因鉴定及温度胁迫响应功能分析

探讨核桃(Juglans regia)热激蛋白响应温度胁迫的分子调控机理,为核桃防寒工作等提供理论指导.通过对核桃‘香玲’转录组分析获得1个热激蛋白家族基因HSP20(命名为JrHSP20-1)的全长cDNA序列.采用实时荧光定量PCR(qRT-PCR)技术分析在40,44,48,16,10,6℃胁迫下JrHSP20-1在核桃根、茎、叶中的表达.并将JrHSP20-1构建酵母表达载体PYES2-JrHSP20-1进行温度胁迫功能分析.结果显示,JrHSP20-1基因全长891bp,编码的蛋白分子量为33.57KD,含296个氨基酸,理论等电点为5.07.表达分析显示,JrHSP20-1在不同组织均有不同程度的表达;根中,44℃时JrHSP20-1被诱导为对照的2.3倍,48℃时达对照的74.5倍,10℃时被诱导为对照的12.0倍;茎中,48℃时上调最大为对照的300.2倍;叶中,在48℃和16℃胁迫下被诱导较高,分别为对照的82.1,53.8倍.酵母温度胁迫实验发现,在53℃和-20℃胁迫下,重组酵母INVSC1(pYES2-JrHSP20-1)的生命活力及恢复活性明显优于对照酵母INVSC1(pYES2).得出核桃JrHSP20-1基因的表达具有一定的组织特性,响应于温度胁迫诱导,且JrHSP20-1基因能有效提高转基因酵母对高温和低温的耐受力,表明JrHSP20-1基因是核桃抗寒耐高温的有效候选基因,为进一步研究JrHSP20-1的抗寒功能打下基础.     

红枣果醋加工工艺研究

红枣汁经果胶酶降解后，经过酵母发酵和醋酸发酵两个阶段制成红枣果醋工艺，以及通过在整个发酵过程中红枣汁中主要物质的浓度变化，摸索红枣汁自然发酵制作果醋的最优工艺条件．从腐烂的苹果中划线分离出3株酵母茵和3株醋酸菌，并在摄像显微镜下做初步的形态鉴定后，并以此作为发酵菌种，研究不同温度、接种量、不同发酵时间对酒精度、还原糖、总糖、酸度影响．结果表明酒精发酵最适温度为30℃，发酵时间为5天，接种量为3％；醋酸发酵最适温度34℃，发酵时间为5天，接种量为10％．     

Effects of oral administration recombinant Saccharomyces cerevisiae expressing human-salmon calcitonin on hypercalcemia rats~

Recombinant human-salmon calcitonin (hsCT) was synthesized and expressed on the cell surfaces of recombinant Saccharomyces cerevisiae (yAGA2-hsCT) using the pAGA2-hsCT expression vector.Expression of r...     

利用双启动子质粒在毕赤酵母中高效表达人FGF1

基于p PIC9K构建了同时含有AOX1和FLD1的双启动子质粒,并成功转入毕赤酵母GS115中,建立了一个新型的全长人活性FGF1表达系统。测序结果和SDS-PAGE显示质粒构建成功,两种启动子可同时被甲醇诱导。液质联用分析表明,目的蛋白的氨基酸组成与人源性FGF1基本一致,且在生物活性测定中表现出良好的生物相容性。经过大规模发酵与凝胶过滤层析,重组FGF1蛋白的产量为197 mg/L,约为当前报道的最高表达水平的两倍,且纯度达到97%。     

马克斯克鲁维发酵饮料的研制

本文主要研究应用一株从“藏灵菇”（kefir粒）中分离的马克斯克鲁维酵母菌[kluyveromycesmarxlanus （E.C.hansen） van der walt]日，以选自天然食品来源的材料为培养基质，在适当的pH、温度环境下通过传统和现代工艺发酵，获得了一种富含多种营养和健康活性因子的发酵基料。卫生安全毒理学检验证明：该基料属无毒级。将这一基料通过一系列后续处理、调制勾兑，研制成了一种集营养、天然、健康于一体的有机发酵饮料。感官评定与志愿试食者认为：该饮料营养丰富、口味干爽，是一种良好的新型绿色有机饮品。     

Does Yeast Suicide？

There has been much controversy on whether the single-cell eukaryote yeast undergoes programmed cell death(PCD),or so-called apoptosis.The only caspase-related gene,YCAl,also termed MCAl(encoded by Yorl97w),identified in the yeast genome so far,suggests that apoptosis does occur in the unicellular organism Saccharomyces cerevisiae. Ycal belongs to the metacaspase subfamily of caspase family in clan CD protease family.Caspase is a family of Cysteine proteases that specifically hydrolyzes aspartyl bonds.Metacaspases,on the other hand,     

酵母菌种的单倍体分离及其原生质体的再生、融合的研究

采用酶法和复合作用法对酵母菌株 13 0 0 (2N)和 2 0 10 (2N)的单倍体细胞 (1N)的获得率分别为3 0 %和 2 0 %左右 由实验确定脱子囊壁的最佳条件为采用生理盐水 ,pH5 .4 ,温度为 2 7℃ ,获得A型 ,B型两种单倍体细胞 (IN) 通过群体杂交法 ,从 75个平板上 ,挑选出 14 5个小菌落 ,得到 5个营养缺陷型菌株 ,该菌株的原生质体在 3 5 %PEG的作用下进行原生质体的融合 ,获得成功 但是仍需进一步对融合体进行生理、生态的研究     

Construction of recombinant industrial Saccharomyces cerevisiae strain with bglS gene insertion into PEP4 locus by homologous recombination

The bglS gene encoding endo-1,3-1,4-β-glucanase from Bacillus subtil＆ was cloned and sequenced in this study. The bglS expression cassette, including PGK1 promoter, bglS gene fused to the signal sequence of the yeast mating pheromone a-factor （MFals）, and ADH1 terminator with G418-resistance as the selected marker, was constructed. Then one of the PEP4 allele of Saccharomyces cerevisiae WZ65 strain was replaced by bglS expression cassette using chromosomal integration of polymerase chain reaction （PCR）-mediated homologous recombination, and the bglS gene was expressed simultaneously. The recombinant strain S. cerevisiae （SC-βG） was preliminarily screened by the clearing hydrolysis zone formed after the barley β-glucan was hydrolyzed in the plate and no proteinase A （PrA） activity was measured in fermenting liquor. The results of PCR analysis of genome DNA showed that one of the PEP4 allele had been replaced and bglS gene had been inserted into the locus of PEP4 gene in recombinant strains. Different endo-1,3-1,4-β-glucanase assay methods showed that the recombinant strain SC-βG had high endo-1,3-1,4-β-glucanase expression level with the maximum of 69.3 U/（h·ml） after 60 h of incubation. Meanwhile, the Congo Red method was suitable for the determination of endo-1,3-1,4-β-glucanase activity during the actual brewing process. The current research implies that the constructed yeast strain could be utilized to improve the industrial brewing property of beer.     

精炼糖废蜜连续发酵生产酵母的研究

研究了以精炼糖废蜜为原料，采用连续多级发酵制作酵母的工艺过程，确定出适用进糖浓度与最佳稀释率等工艺参数