脂肪酶菌种的筛选及分子鉴定

通过固体平板法,从温泉水样中筛选出1株耐热脂肪酶产生菌X-33。对该菌株进行了产酶条件的初步探索,得出其摇瓶发酵条件为：2%可溶性淀粉,3%酵母膏,MgSO4·7ddH2O 0.1%,K2HPO40.1%,三丁酸甘油酯乳化液0.1%,起始pH值7.5,通气量50 mL/250 mL摇瓶,250 r/min,发酵温度37℃,发酵周期24 h。该酶在60℃条件下温浴30 min,可保留部分活性。为鉴定该菌株,克隆并测序了其16S rDNA基因序列,NCBI上比对分析表明,该菌株与sphingomonas yabuuchiae（鞘氨醇单胞菌）有最紧密的亲缘关系。

Screening and Molecular Identification of Lipase Producing Strain

A heat resistant lipase producing strain X-33 was screened by solid plate method.The conditions for lipase production were groped.The optimized flask-shaking fermentation condition contained 2% soluble starch,3% yeast extract,0.1% MgSO4·7ddH2O,0.1% K2HPO4,0.1% tributyrylglycerols emulsion with initial pH value 7.5,ventilation volume 50 mL/250 mL at 37 ℃ for 24 h.16S rDNA gene sequence of X-33 showed strong homology with Sphingomonas yabuuchiae.