为了对兰州市榆中县某奶牛场犊牛疑似肺炎克雷伯氏菌感染病例进行确诊,本研究采集病死犊牛的脏器组织并从中分离到1株革兰阴性短杆菌,进而对分离菌进行了生化鉴定、16S r RN A鉴定及khe基因鉴定,在此基础上,完成了分离菌的致病性试验、...为了对兰州市榆中县某奶牛场犊牛疑似肺炎克雷伯氏菌感染病例进行确诊,本研究采集病死犊牛的脏器组织并从中分离到1株革兰阴性短杆菌,进而对分离菌进行了生化鉴定、16S r RN A鉴定及khe基因鉴定,在此基础上,完成了分离菌的致病性试验、耐药性分析及主要毒力基因的遗传进化分析。结果显示,除H2S试验外,分离菌生化特性均符合肺炎克雷伯氏菌的生化反应特性,其16S r RNA及khe基因序列与G enB ank中肺炎克雷伯氏菌株之间的同源性均高达99%,因此,可将分离菌确定为肺炎克雷伯氏菌,并将其命名为YZ2015。动物试验及耐药性试验结果表明,分离菌具有较强的致病性和多重耐药性。遗传进化分析表明,分离菌的fim H、mrk D及wab G基因与肺炎克雷伯氏菌其他菌株具有很高的同源性,其核酸序列相似性高达95%以上。展开更多
The production of 2,3-butanediol by Klebsiella pneumoniae from glucose supplemented with different salts was studied. A suitable medium composition was defined by response surface experiments. In a medium containing g...The production of 2,3-butanediol by Klebsiella pneumoniae from glucose supplemented with different salts was studied. A suitable medium composition was defined by response surface experiments. In a medium containing glu-cose and (NH4)2HPO4, the strain could convert 137.0g of glucose into 52.4g of 2,3-butanediol and 8.4g of acetoin in shaking flasks. The diol yield amounted to 90% of its theoretical value and the productivity was 1—1.5g·L-1·h-1. In fed-batch fermentation, the yield and productivity of diol were further enhanced by maintaining the pH at 6.0. Up to 92.4g of 2,3-butanediol and 13.1g of acetoin per liter were obtained from 215.0g of glucose per liter. The diol yield reached 98% of its theoretical value and the productivity was up to 2.1g·L-1·h-1.展开更多
文摘The production of 2,3-butanediol by Klebsiella pneumoniae from glucose supplemented with different salts was studied. A suitable medium composition was defined by response surface experiments. In a medium containing glu-cose and (NH4)2HPO4, the strain could convert 137.0g of glucose into 52.4g of 2,3-butanediol and 8.4g of acetoin in shaking flasks. The diol yield amounted to 90% of its theoretical value and the productivity was 1—1.5g·L-1·h-1. In fed-batch fermentation, the yield and productivity of diol were further enhanced by maintaining the pH at 6.0. Up to 92.4g of 2,3-butanediol and 13.1g of acetoin per liter were obtained from 215.0g of glucose per liter. The diol yield reached 98% of its theoretical value and the productivity was up to 2.1g·L-1·h-1.
