【作者】 王冬梅；

【导师】 李多川；

【作者基本信息】 山东农业大学 ， 植物病理学， 2005， 硕士

【摘要】 嗜热真菌在高温条件下具有独特的生存适应能力,产生嗜热酶等特殊的代谢产物,是研究生物进化和热稳定酶的重要微生物来源。本研究的第一部分主要是进行了中国嗜热真菌的分类研究。从2002-2004 年本实验室采集的600 多份标本中共分离鉴定到嗜热真菌15种,其中,新种1 个,中国新记录种9 个,中国已报道种4 个,不确定种1 个,另外还分离鉴定了4 种耐热真菌。本研究较全面、系统地对嗜热真菌进行了考察、收集、分离、鉴定和形态描述,并分别对每个种的基质、生境及分布等做了统计,对相似的种间进行了比较和讨论。在前人工作的基础上,增加了新种及若干新记录种,总结出比较简便易行的种级分类标准和我们自己的分类观点。孢子的特征(包括形状、大小、颜色、隔膜数和表面纹饰等)是种级分类的主要依据,一些形态差异较大的孢子可作为属的划分标准;其次,分生孢子梗的形态特征、产孢细胞的延伸方式及产孢方式也是主要的鉴别依据,对属级水平上该真菌的鉴别有重要意义;另外,培养特征及产孢表型可作为分类鉴定的必要、有益补充。嗜热子囊菌光孢变种在45~50℃高温下生长旺盛,产生的纤维素酶在高温条件下保持较高的活力和热稳定性。本研究的第二部分主要是探讨了该嗜热真菌产生的内切β-葡聚糖酶与β-葡萄糖苷酶的分离纯化及特性研究。粗酶液依次经硫酸铵分级沉淀、DEAE-Sepharose 阴离子层析、Pheny1-Sepharose 疏水层析、SephacrylS-100 分子筛层析等步骤获得凝胶电泳谱带均一的内切β-葡聚糖酶和β-葡萄糖苷酶。经12.5%SDS-聚丙烯酰胺凝胶电泳和凝胶过滤层析法分别测得所纯化的内切β-葡聚糖酶分子量介于31.5kDa~34.5kDa 之间;所纯化的β-葡萄糖苷酶分子量约为350kDa,为同源三聚体蛋白质。更多还原

【Abstract】 Thermophilic fungi with unusual ability can survive under hightemperature condition, producing special metabolization such asthermozymes, and it is considered to be essential microorganism source forstudying organic evolution and thermozymes.The first part of this study ismainly about the taxonomic research of thermophilic fungi in China.Wecollected and checked a sum of over 600 specimens from 2002 to 2004,from which about 50 isolates were received. We discovered quite a fewnew and noteworthy taxa and achieved many valuable results based on thecareful identificatin. 19 taxa at species level are described and illustrated.Among them, there are 1 new species, 9 Chinese newly recored species, 8reported species from China including 4 thermotolerant fungi.Besides the new species, new record species discovered, we counted thehabits and distributions of the species respectively, discussed andsummarized the similar species. As a result, some valuable taxonomicmethods, criteria and our viewpoints were concluded. The morphology ofthe sporus is the main identical base at species level, which include thecharacters of the shape, size, colour, septate and ornament of the wall etc,and some sporus with distinct variable are also useful at genus level.Secondly, the characters of the conidiophore, the extending mode of theconidiogenus cells and conidiogenous pattern are key to distinguish thesefungi at genus level. In additin, the culture features and sporulation patternare essential and helpful complement for identification work..Thermoascus aurantiacus var. levisporus can be well thrive attemperature between 45 and 50℃, cellulases from it have reported to keephigher activity and thermostibility The second part of the study mainlydiscussed the purification and characterization of endocllulase.and β-glucosidase from Thermoascus aurantiacus var.levisporus.The endocellulase and β-glucosidase from culture supernatant waspurifided to homogeneity by using ammonium sulfate fraction, DEAE-Sepharose chromatography, Pheny1-Sepharose Fast Flow chromatographyand SephacrylS-100 chromatography. The molecular mass of the更多还原