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     

猴头啤酒和灵芝啤酒的研制

应用食用菌深层液体发酵技术获得猴头，灵芝菌丝体发酵醪，再经胶体磨使细胞壁破碎后，与啤酒生产原料一起进行啤酒发酵而得猴头啤酒和灵芝啤酒。经检测，酒液中氨基酸总量分别为１６１７．６ｍｇ．Ｌ＾－１和１５１１．５ｍｇ．Ｌ＾－１，其中人体必需氨基酸分别占２０．５１％和２５．３５％。，其他各项指标均符合国家标准。     

酵母渣泥流变特性及粘弹性的测试

用RheometricsRFSⅡ型流变仪对酵母渣泥的流变曲线(r-γ)和粘弹性进行测试；结果显示酵母废渣具有一定的粘弹性，其τ-γ流变曲线有复杂的弯曲形状.在25～35℃范围，当温度处于28～35℃区间时，表观粘度及弹性均随温度的升高而升高.     

固定化啤酒酵母连续发酵动力学模型中总有效因子ηs的计算

对固定化啤酒酵母的乙醇连续发酵动力学模型引入了一个综合考虑颗粒内外扩散的总有效因子以简化模型的计算．文中对该有效因子进行了详细的理论推导，得出了具体的计算式，并对该因子出现大于１的特殊情况进行了深入探讨．     

Actin-, myosin- and ubiquitin-dependent endocytosis

Endocytosis is a general term that is used to describe the internalization of external and plasma membrane molecules into the cell interior. In fact, several different mechanisms exist for the internalization step of this process. In this review we emphasize the work on the actin-dependent pathways, in particular in the yeastSaccharomyces cerevisiae, because several components of the molecular machinery are identified. In this yeast, the analysis of endocytosis in various mutants reveals a requirement for actin, calmodulin, a type I myosin, as well as a number of other proteins that affect actin dynamics. Some of these proteins have homology to proteins in animal cells that are believed to be involved in endocytosis. In addition, the demonstration that ubiquitination of some cell surface molecules is required for their efficient internalization is described. We compare the actin, myosin and ubiquitin requirements for endocytosis with recent results found studying these processes usingDictyostelium discoideum and animal cells.     

具有嗜杀质粒(killer plasmid)酵母菌嗜杀特性的初步研究

以K_2型嗜杀酵母为材料在改进Russell(1986)的嗜杀活性检测方法基础上,建立了双层平板单菌落检测法。此法可直接用于嗜杀酵母的筛选,嗜杀质粒的检测,并能在诱变后的平板上检出有嗜杀活性的营养缺陷型菌株MK_2-3:K~+,len。对K_2嗜杀特性初步研究表明,K_2型嗜杀酵母能杀死酿酒酵母(Saccha-romyces cerevisiae),但对所测汉逊酵母(Hansenula spp.)无作用。嗜杀毒素产生的最适pH和温度分别为pH4.5—5.5和20—25℃,酵母菌的对数生长期嗜杀毒素达到高峰。用紫外线(UV)、溴化乙锭(EB)、亚硝基胍(NTG)和甲基磺酸乙酯(EMS)进行消除K因子实验,表明亚硝基胍和紫外线对K因子具有一定消除率,而溴化乙锭和甲基磺酸乙酯未发现消除作用。     

An integrative model and analysis of cell cycle in fission yeast

Cell cycle is a programmed process, during which a cell proliferates to two daughter cells. The eukaryotic or-ganisms share the same characters, such as four cycle phases G1, S, G2 and M, the evolutionally conserved cell cycle proteins and its dependent kinases, and the check-points mechanism[1,2]. Due to the different functions and the complicated interactions of these proteins involved in cell cycle, it is very difficult to understand the regulatory mechanism of cell cycle in a whole sense …     

羧基在酵母菌生物吸附铅时的作用

用不同方法研究了酵母菌吸附重金属的机理.电位滴定法的结果说明生物材料含有0.5 mmol/g的酸性基团;酯化后的酵母菌对重金属的吸附量显著下降.对酯化前后的生物材料的红外光谱进行了比较,1 744 cm-1的吸收峰强度的增加证明酵母菌发生了酯化过程.羧基在酵母菌结合铅时起重要作用.     

紫外分光光度法测定啤酒酵母水溶性多糖的含量

采用紫外分光光度法对啤酒酵母中水溶性多糖的含量进行测定,发现啤酒酵母水溶性多糖在波长489nm处有最大吸收峰。葡萄糖浓度在1.55~13.286μg.mL-1(r=0.9989)范围内、线性关系良好,平均回收率在6.1%,RSD为2.3%。     

Interaction between PⅡ and NifA in Azospirillum brasilense Sp7

The interaction between PⅡ and NifA in A.brasilense Sp7 was investigated by using the yeast two-hybrid system.Our experimental results showed that PⅡ directly interacted with the entire NifA protein and its N-terminal domain,but did not interact with the central domin and the C-terminal domain of NifA.No interaction happened if glnB coding for PⅡ was frame-shift mutated.Pz,a homolog of PⅡ,had no interation with NifA.