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991.
Goda H Nagase T Tanoue S Sugiyama J Steidl S Tüncher A Kobayashi T Tsukagoshi N Brakhage AA Kato M 《Archives of microbiology》2005,184(2):93-100
The CCAAT-binding complex in the Aspergillus species, also known as the Hap complex, consists of at least three subunits, namely HapB, HapC and HapE. Each Hap subunit
contains an evolutionary conserved core domain. Recently, we have found that the HapC and HapE subunits do not carry a nuclear
localisation signal. Furthermore, when in complex with HapB, they are transported into the nucleus via a ‘piggy back mechanism’
in A. nidulans. To extend our findings to other filamentous fungi, we examined the nuclear localisation of the A. oryzae Hap subunits by analysing several GFP fusion proteins with these Hap subunits in the hap deletion strains of A. nidulans. The nuclear translocation of the A. oryzae complex was found to be dependent on two redundant localising signals in HapB. 相似文献
992.
Kari E. Reijula 《Mycopathologia》1991,113(3):143-149
The fine structure of Aspergillus fumigatus and Aspergillus umbrosus by transmission electron microscopy (TEM) is described. The fine structure of the ascosporic and asexual stages of A. umbrosus is described for the first time. Dense, homogenous material and fibers were detected on the outer hyphal cell wall of the Aspergilli. Septal pores were found in the hypha of A. umbrosus. Two wall layers were detected in the cell wall of the conidia of the both Aspergilli. The ascospores of A. umbrosus contained thick cell wall and the surface of which was smoother than that of the conidia. 相似文献
993.
bHLH(Basichelix-loop-helix)转录因子广泛存在于真核生物中,它可以通过同源或异源二聚体的形式与基因启动子上的E-box结合来调控基因的表达。转录因子的bHLH家族由广泛涉及发育过程(包括细胞增殖和分化)的大量蛋白组成,在生物的生长发育调控过程中起着极为重要的作用。本文对包括构巢曲霉、烟曲霉、米曲霉等曲霉属中现已发现bHLH转录因子的调控过程和生物功能进行概述,以期为深入研究曲霉属的生长发育及bHLH转录因子的功能提供理论参考。 相似文献
994.
995.
【目的】实现黑曲霉来源的阿魏酸酯酶在毕赤酵母(Pichia pastoris GS115)中的组成型表达。【方法】以黑曲霉(Aspergillus niger)基因组为模板,经重叠延伸PCR扩增得到阿魏酸酯酶基因(AnfaeA),将其与载体pGAP9K相连,构建重组表达载体p GAP9KAnfae A,经SalI线性化后电转入毕赤酵母GS115中,得到重组菌株。高效液相色谱法测定发酵液中阿魏酸酯酶活力,并对重组菌进行了发酵优化。【结果】克隆得到783 bp的阿魏酸酯酶编码基因并实现了其在毕赤酵母中的组成型表达。重组菌发酵84 h后,上清液中酶活达5.72±0.10 U/m L。重组酶(reAnfaeA)经分离纯化后比酶活为59.75 U/mg,大小约为40 k D。发酵优化结果为:葡萄糖40.0 g/L,蛋白胨10.0 g/L,酵母膏30.0 g/L,CaCO_3 0.2 g/L,种龄28 h,接种量3%(体积比),装液量50 m L/250 m L。在此条件下发酵培养,酶活达15.60±0.23 U/m L。【结论】阿魏酸酯酶在毕赤酵母中的组成型表达,对研究毕赤酵母组成型表达系统和阿魏酸酯酶的发酵生产具有一定的借鉴意义。 相似文献
996.
促进紫草色素合成的米曲霉诱导子的纯化和活性鉴定 总被引:1,自引:0,他引:1
米曲霉(Aspergillusoryzae)诱导子来源于该真菌的菌丝体部分。诱导子粗提物通过DEAE-Cellu-lose、Sepharose-4B、Bio-Gelp-4、732 柱层析,得到既不吸附于阴离子交换纤维素又不吸附于阳离子交换树脂、分子量约为1200~2200 D、糖含量为粗提物6.7% 的组分FⅠb2-H,与粗提物相比它的诱导子相对活性提高了120 倍。诱导子粗提物中还含有低浓度不影响滇紫草(Onosm a paniculatum )细胞合成紫草色素、而高浓度抑制紫草色素合成的核酸类组分FⅡ,核苷酸、氨基酸类组分FⅠb2-Na 及强烈抑制紫草色素合成的多糖类组分FⅠa。FⅠa可诱导细胞合成对照中没有的一种黄色素,是另一类代谢产物的诱导子 相似文献
997.
考察了利用赭曲霉Aspergillus ochraceusNG1203进行C11α-羟基化齐墩果酸生化反应的条件。得出了菌株摇瓶培养最佳培养基配方(g.L-1):葡萄糖20,玉米浆25,酵母膏3,K2HPO41.5,pH 6.0。菌株培养20 h,加入2 mg.L-1的齐墩果酸利于诱导羟基化酶的产生。菌株在28℃下以150 r.min-1振荡培养24 h,加入底物的乙醇溶液,使转化液中齐墩果酸的初始质量浓度达100 mg.L-1,转化液中乙醇体积分数最终达3%。经96 h转化,齐墩果酸转化率可达到10.12%。通过HPLC1、H NMR和13C NMR分析,结果表明产物为C11α-羟基齐墩果酸。 相似文献
998.
KO TOMIKAWA NORIO KOBAYASHI HIROSHI MORINO SHUNSUKE F. MAWATARI 《Zoological Journal of the Linnean Society》2007,149(4):643-670
Luciobliviidae, a new family in the superfamily Gammaroidea (Amphipoda: Crustacea), is described on the basis of species in the genus Lucioblivio gen. nov. from subterranean waters of Japan. Mesogammaridae Bousfield, 1977 is rediagnosed; Octopupilla gen. nov. from subterranean waters of Japan is described and Eoniphargus (Uéno, 1955) from subterranean waters of Japan and Korea is included. The members of Lucioblivio , Octopupilla and Eoniphargus share several characters, including reduced eyes, a setose body, reduced coxae, feeble appendages and pedunculate coxal gills. To elucidate the phylogeny of the three genera among others, a sequence analysis of the 28S rRNA gene was conducted for 14 species in six families, including the three genera, from the superfamilies, Gammaroidea, Crangonyctoidea and Hadzioidea. The tree from a neighbour-joining analysis and the strict consensus tree from a maximum-parsimony analysis indicate monophyly of Mesogammaridae. Luciobliviidae is embedded within a clade of taxa belonging to the superfamily Gammaroidea. These results and the occurrence of gammarid-type calceoli in species of the new family indicate that Luciobliviidae should be placed within the superfamily Gammaroidea. © 2007 The Linnean Society of London, Zoological Journal of the Linnean Society , 2007, 149 , 643–670. 相似文献
999.
1000.
Joseph P. Chinnici 《Journal of invertebrate pathology》1980,35(2):190-194
Toxicity studies, using outbred lines with much genetic variability and isogenic lines with no genetic variability from two strains of Drosophila melanogaster, Lausanne-S and Oregon-R, are reported. In both of these wild-type strains, larval and pupal development are known to be relatively resistant to the toxic effects of media containing aflatoxin B1, a mycotoxin with carcinogenic and mutagenic properties. To eliminate genetic variability, each strain was made “isogenic” by a standard chromosomal substitution technique. Each isogenic strain, in comparison to the appropriate outbred control strain, showed a significant decrease in egg-to-adult viability when offspring were allowed to develop from the egg stage on media containing 1.0 ppm aflatoxin B1. However, the resistance levels shown by the offspring of crosses between the two isogenic strains were not significantly different in viability than those of the appropriate controls. The relationship of these results with the level of genetic variability prossessed by the outbred and isogenic lines is discussed. 相似文献