在土壤杆菌ZX09中透明颤菌血红蛋白的表达提高索拉胶的产量

研究目的：提高胞外多糖索拉胶的产量。 创新要点：透明颤菌血红蛋白基因在质粒上表达,不加抗生素发酵生产索拉胶。 研究方法：将透明颤菌血红蛋白基因构建到广谱质粒pCM158上得到重组质粒pCM158-vgb,重组质粒转入土壤杆菌ZX09中,使透明颤菌血红蛋白在土壤杆菌ZX09中表达。 重要结论：在土壤杆菌ZX09中颤菌血红蛋白的表达解决了发酵过程中氧受限的问题,提高了宿主菌的呼吸速率、蔗糖酶活性和黏度,将发酵产物索拉胶的产量提高了30％。     

芽孢杆菌葡萄糖脱氢酶结构与功能研究进展

芽孢杆菌葡萄糖脱氢酶在辅酶再生方面具有良好的应用前景,因而受到了广泛关注.本文结合葡萄糖脱氢酶的三维结构和生理生化特性,尝试建立起其结构与功能方面的相关关系,为葡萄脱氢酶的体外改造提供有价值的信息,并指出了目前应用上存在的问题,对发展趋势做了展望.     

一株高产黑色素链霉菌的分离筛选和初步鉴定

从鄱阳湖草洲土壤中分离出一株高产黑色素的细菌(g2B),g2B具有产黑色素速度较快,并且不需要Tyr诱导等优点.在同等条件下其产黑色素能力最强,经提取纯化后产量可达19mg/mL.纯化后的黑色素的红外光谱与SIGMA公司标准黑色素红外光谱图谱基本一致.生理生化分析结果及16s rDNA扩增和序列分析鉴定其种属类型,初步鉴定g2B属于Streptomyces sp..     

也谈"吃饭"与体育目标

长时间以来我国体育界对学校体育的作用和目标存在着很大争议。有名学以“吃饭”为例,详细地阐述了“吃饭”的功能和目标,并引申到体育,引起了体育界的较大反响。在该问题上作从另一角度谈了“吃饭”与体育目标的问题。     

Analysis of both chitinase and chitosanase produced by <Emphasis Type="Italic">Sphingomonas</Emphasis> sp. CJ-5

A novel chitinolytic and chitosanolytic bacterium, Sphingomonas sp. CJ-5, has been isolated and characterized. It secretes both chitinase and chitosanase into surrounding medium in response to chitin or chitosan induction. To characterize the enzymes, both chitinase and chitosanase were purified by ammonium sulfate precipitation, Sephadex G-200 gel filtration and DEAE-Sepharose Fast Flow. SDS-PAGE analysis demonstrated molecular masses of chitinase and chitosanase were 230 kDa and 45 kDa respectively. The optimum hydrolysis conditions for chitinase were about pH 7.0 and 36 °C, and these for chitosanase were pH 6.5 and 56 °C, respectively. Both enzymes were quite stable up to 45 °C for one hour at pH 5~8. These results show that CJ-5 may have potential for industrial application particularly in recycling of chitin wastes.     

磁场处理在诺卡氏菌诱变选育中作用的研究

诺卡氏菌HD9611经紫外线诱变处理后在磁场条件下进行培养，其诱变致死率和营养缺陷的诱发率均比诱变后在自然条件下培养的要高，并且经UV＋磁场复合诱变所筛选出的菌株酶活也单纯紫外线处理的时照菌株平均酶活相对提高了17．2％。     

Direct transformation of n-alkane into all-trans conjugated polyene via cascade dehydrogenation

Selective C(sp³) −H activation is of fundamental importance in processing alkane feedstocks to produce high-value-added chemical products. By virtue of an on-surface synthesis strategy, we report selective cascade dehydrogenation of n-alkane molecules under surface constraints, which yields monodispersed all-trans conjugated polyenes with unprecedented length controllability. We are also able to demonstrate the generality of this concept for alkyl-substituted molecules with programmable lengths and diverse functionalities, and more importantly its promising potential in molecular wiring.     

木霉菌防治油菜菌核病和辣椒白绢病的研究

本文报道了一种生物保护剂──本霉菌防治抽菜核病和辣椒白绢病的途径及效果．     

温度、pH及碳氮源对产色素青霉菌株（Penicilliumsp．）生长的影响

PSO312是从土壤分离的1个青霉菌株,生长中能产生不同酸碱性条件下显黄色与紫红色等天然色素物质．通过菌株固体平板上恒温培养,168h测定菌落直径的方法研究了温度、pH及碳、氮源对菌株（Penicilliumsp．）生长的影响．研究表明31℃为菌株生长的最适温度．31℃培养以pH2—3的最快,pH8—9生长次之,24℃培养以pH8—9生长最快,pH3—4其次．菌株以蛋白胨4g／L、牛肉膏4g／L、酵母膏2g／L及尿素2g／L为氮源培养的菌落直径分别为55．75mm、51．5mm、55．5mm及25．3mm．在（NH4）2SO4 2g／L、NH4NO3 3g／L、NaNO3 4g／L、KN034g／L用量之上培养生长最快,菌落直径分别为35mm、34mm、35mm、及32mm．葡萄糖、蔗糖用量30g／L、果糖20g／L及乳糖25g／L的生长速率最快,菌落直径分别为45mm、38mm、38mm及39mm．丙三醇与淀粉25g／L培养的菌落直径均为39mm．