【摘要】 从酒鬼酒窖池中采集成熟酒醅样品,用纯培养法进行芽孢杆菌分离纯化,采用16S rRNA基因序列分析法进行系统发育分析,采用水解法对其胞外酶学特征进行观察。采用NA和LA培养基分离纯化得到104株细菌菌株,根据形态特征和产芽孢特征,去除部分冗余,选择28株代表性芽孢杆菌用于进一步研究。系统发育分析结果表明,这28株芽孢杆菌具有较高的类群多样性和物种多样性,属于细菌域(Bacteria)厚壁菌门(Firmicutes)的2个科(Bacillaceae、Paenibacillaceae)的3个属(Bacillus、Brevibacillus、Virgibacillus),分为10个物种。芽孢杆菌属(Bacillus)占绝对优势,共26株(92.9%);其余2株JSM161009和JSM 166025分属于枝芽孢杆菌属(Virgibacillus)和短芽孢杆菌属(Brevibacillus)。胞外水解酶学特征观察结果表明,至少产生一种酶的菌株共27株(96.4%)。其中有20株(71.4%)淀粉水解酶阳性,19株(67.9%)明胶水解酶阳性,27株(96.4%)尿素水解酶阳性,21株(75.0%)对4种吐温(20、40、60、80)之一水解活性阳性。在28株受试菌株中,有8株(JSM 161009、163010、163017、166014、167011、167021、168017、168019)水解酶谱较广。这8个菌株均属于芽孢杆菌科(Bacillaceae),其中1株(JSM161009)属于枝芽孢杆菌属(Virgibacillus),其他7株属于芽孢杆菌属(Bacillus)。更多还原

【Abstract】 In this study, the cultivable bacilli were isolated by culture-dependent method from the fermented grains in the fermentation pits in Jiugui Liquor Distillery. The diversity of the bacilli was investigated by phylogenetic analysis based on 16 S rRNA gene sequence comparisons. Furthermore, the exoenzyme activities were studied by using some conventional methods. According to their morphology and the endospore observation results, 28 representative bacilli out of 104 isolated bacilli were selected for phylogenetic analysis and exoenzyme observation. The results of phylogenetic analysis showed that the 28 bacilli represented 10 species belonging to 3 genera(Bacillus, Brevibacillus, and Virgibacillus) of 2 families(Bacillaceae and Paenibacillaceae) in 1 phyla(Firmicutes).Among the 28 bacilli, the dominant genus was Bacillus(26 strains, 92.9 %), and the other 2 strains, JSM 161009 and JSM 166025,belonged to Virgibacillus and Brevibacillus respectively. The exoenzyme observation showed that, 27 out of 28(96.4 %) bacilli produced at least one enzyme, among them, 20 strains(71.4 %) were amylase-positive,19 strains(67.9 %) were gelatinase-positive, 27 strains(96.4 %) were urease-positive, 21 strains(75.0 %) were esterase-positive(Tweens 20, 40, 60 and 80), and 8 bacilli strains(JSM 161009, 163010, 163017, 166014, 167011, 167021, 168017, 168019) showed a relatively broad spectrum of exoenzymes.These 8 bacilli belonged to the family of Bacillaceae(strain JSM 161009 belonged to the genus Virgibacillus, and the other 7 strains belonged to the genus Bacillus).更多还原