A new strategy for cellulases application in high temperature industrial scenarios with syringic acid assisting

In the process of bioethanol production, more stable and active cellulase in high temperature condition is required. In this study, syringic acid was applied in cellulase hydrolysis system. At 70°C, TvEG3 activity increased 201.36%, CtBglA activity decreased 72.79% by syringic acid. With syringic acid assisting, TvEG3 thermostability was improved, CtBglA thermostability was reduced. Syringic acid scarcely affected CtCBH. In hydrolysis system with the cellulases containing TvEG3, CtCBH, and CtBglA, the reducing sugar yield improved by 28.37% with syringic acid assisting. With the molecular dynamic simulation in syringic acid system, the backbone root-mean-square deviation (RMSD) and the residue root-mean-square fluctuation (RMSF) of TvEG3, CtCBH reduced, while the RMSD and RMSF of CtBglA increased. The reduction in the number of secondary structures, especially α-helix, caused the structure of CtBglA in the presence of syringic acid to collapse at high temperature. More secondary structures in TvEG3 and more α-helix in CtCBH in the presence of syringic acid make them more stable at high temperatures. These means syringic acid can stabilize TvEG3 and CtCBH structure, destabilize CtBglA structure at high temperature. In summary, this study not only provides insight into cellulase hydrolysis at high temperature with syringic acid assisting but also demonstrates the promoting mechanism of syringic acid.     

I型马立克氏病毒38kD磷蛋白与Ⅱ和Ⅲ型病毒间的交叉免疫反应

由致病性Ⅰ型马立克氏病病毒(MDV)特异性的单克隆抗体H_(19)制备亲和层析柱,从感染重组杆状病毒BP38Ⅱ的昆虫细胞系Sf9细胞中提纯MDV的pp38基因表达产物,以此免疫小鼠制备抗血清,测定其与不同型MDV毒株感染的鸡胚成纤维细胞免疫反应性,同时也用不同型MDV毒株(HVT,Z4)制备的抗血清和自然感染发病鸡血清分别与感染重组病毒的Sf9细胞进行免疫交叉反应.试验结果表明,完整的Ⅰ型MDV来源的pp38基因产物与所试Ⅱ型Z4株和Ⅲ型HVT Fc126毒株在抗原性上有显著交叉反应.这一结果表明,在Ⅱ型和Ⅲ型MDV毒株中可能存在着pp38的类似物.     

DETERMINING THE ADULT AGE OF THE ORIENTAL LATRINE FLY, CHRYSOMYA MEGACEPHALA (FABRICIUS) (DIPTERA: CALLIPHORIDAE) BY PTERIDINE FLUORESCENCE ANALYSIS

The relationship between head pteridine fluorescence (HPF) levels and age in adult females and males of a common necrophagous fly, Chrysomya megacephala, and effects of temperature and fly sex on the relationship were studied by pteridine fluorescence spectrophotometry. Factors affecting HPF levels in flies were found to include fly age, temperature and fly sex, among which the fly age was the most dominant one. There were significant linear relationships between HPF levels and age both for female and male adult flies at five constant temperatures, i. e. 16°C, 20°C, 24°C, 28°C and 32°C. The relationship between mean rate of pteridine accumulation (FV or MV) and temperature (t) could be well described by a modified exponential equation of FV=0.01288 e^{(0.2241t‐3.127)}+0.3649 (r²= 0.9987) for females and a linear regression equation of MV= 0.0574 t ‐ 0.3637 (r²= 0.9557) for males. Using the information from the experiments at five constant temperatures, three calculated methods as the candidates were developed for accurately determining the age of the fly by HPF levels at ambient temperature. The results revealed that these three methods were suitable for estimating the age only for male flies, but not for female flies. The smallest average error of the predicated age was 2.55 days for males. In addition, how to employ which of these three developed methods for determining ages of male flies in practical was also discussed.     

鱼类精子携带的外源基因导入

将鲤鱼（或泥鳅）精子在保存液内与人生长激素（ｈＧＨ）重组质粒ＤＮＡ保温,再与鲤（或泥鳅）卵受精。由此发育的鱼苗经ＤＮＡ分子杂交和ＰＣＲ检测证明,３３．３％（或３７．０％）的个体带ｈＧＨ基因,其拷贝数在４—１５０／细胞之间。在一定条件下,精子可作为携带外源基因的载体,通过受精作用产生转基因鱼。     

辽西半干旱地区深松中耕对作物产量的影响及其作用机理研究

对辽宁西部半干旱地区深松中耕对作物产量影响及作用机理的研究表明,深松打破了犁底层,减小了土壤容重及穿透阻力,增加了表层及亚表层土壤的孔隙度．深松土壤水分人渗可达８０ｃｍ,大豆根系深度增加３．６～４．０ｃｍ,大豆产量和水分利用效率分别增加２７．７～３４．５％和１６．１％,在干旱年份玉米增产７．９％．     

迷宫漏斗蛛Agelena labyrinthica的染色体(蜘蛛目:漏斗蛛科)

报告迷宫漏斗蛛的染色体数目、形态结构和性染色体组成。结果表明,迷宫漏斗蛛体细胞染色体数目是:雄性2n=42,雌性2n=44,性别决定机制属X_1X_2O型。X染色体是全部染色体中最长的和最短的2个(对)。染色体似乎均为端或亚端着丝粒染色体,这由C-显带标本分析所证实,没有亚中着丝粒染色体的证据。C-带标本分析表明,常染色体中,各条染色体的C-带纹,其大小和染色深浅无明显差异,但X_2染色体上有明显宽的C-带纹。C-显带处理没有得到稳定的有重复性的带纹。     

GM_3对小鼠腹腔巨噬细胞磷脂代谢转换率的影响

神经节苷脂ＧＭ_３对小鼠腹腔常驻巨噬细胞（Ｒ－Ｍ）和Ｇｅ－１３２体内激活的巨噬细胞（Ｇｅ－１３２－Ｍ）的磷脂代谢转换有显著的影响,当这两种Ｍ在体外用ＧＭ_３处理时,表现出［￣（３２）Ｐ］Ｐｉ和［￣３Ｈ］肌醇参入ＰＩ降低,参入ＰＩＰ、ＰＩＰ_２增加;但在［￣（３２）Ｐ］Ｐｉ和［￣３Ｈ］胆碱参入ＰＣ上,Ｒ－Ｍ与Ｇｅ－１３２－Ｍ不同,即ＧＭ_３促进同位素前体参入Ｒ－Ｍ的ＰＣ,抑制它们参入Ｇｅ－１３２－Ｍ的ＰＣ．以上结果表明ＧＭ３可能提高了ＰＩ或ＰＩＰ的磷酸激酶的活性,致使［￣（３２）Ｐ］ＰＩＰ和［￣（３２）Ｐ］ＰＩＰ_２增多,［￣（３２）Ｐ］ＰＩ减少．激活的Ｍ（Ｇｅ－１３２－Ｍ）本身ＰＣ代谢转换率较Ｒ－Ｍ高,当Ｇｅ－１３２－Ｍ再受ＧＭ_３刺激,ＰＣ代谢转换率降低,这提示ＧＭ_３对激活的Ｍ的ＰＣ代谢转换有调节作用．     

Isolation of mitochondrial DNA sequences that distinguish male-sterility-inducing cytoplasms in Sorghum bicolor (L.) Moench

We have demonstrated that sorghum DNA sequences of mitochondrial origin can be used to distinguish different male-sterility-inducing cytoplasms. Six DNA clones containing single-copy mitochondrial sequences were hybridized on Southern blots to restriction enzyme-digested DNA of 28 sorghum lines representing sources of different cytoplasmic male-sterility (CMS) groups. Four cytoplasmic types were defined on the basis of the pattern of DNA fragments detected. Similar analyses of 50 additional diverse sorghum accessions suggested that three of the four cytoplasmic types may be diagnostic for CMS. Also, three other cytoplasmic types were discovered. These and other mitochondrial DNA clones may be useful molecular tools for “fingerprinting” sterility-inducing cytoplasms in breeding programs, determining cytoplasmic diversity among germ plasm accessions, and identifying new sources of cytoplasm that induce male sterility.     

超速离心机制备冷冻干燥保存菌种

利用超速离心机原有的冷冻系统和真空系统进行冷冻干燥的方法冻干保存了３０种国际标准菌种,４℃保存一年后,随机检测了其中的１８种,全部存活良好。用本法还可以制备出１、２、３、１０ｍｌ不同容量的冷冻干燥生物制剂,适用于中批量各种冻干生物制剂的生产和研究。一机两用,省资金,省用房,提高了机器的利用率。