产脂肪酶酵母的筛选及其18S rDNA序列分析

The isolation of lipase-producing yeast and the sequence analysis of the 18S rDNA genes

从新疆石河子地区10分土样中,利用罗丹明B为指示剂,筛选到了90株有脂肪酶活性的酵母菌.滴定法测量野生菌株酶活,每毫升培养液酶活为1.1-6.6 U,其中B9,C1,E7,F12等有成为生物催化剂的潜力.扩增了其中脂肪酶活性较高的9株的18S rDNA,测序后BLAST比对,并进行系统进化树分析,表明所得菌株分别与Candida,Rhodotorula,Trichosporon等属亲缘关系接近.进行部分生理生化试验,除H4,H8外,其它菌株结果与18S rDNA分析结论吻合.

Using Rhodamine B as indicator,90 lipase-producing yeasts were isolated from the soil samples of Shihezi in Xinjiang by plate isolation.Using titration to test the enzyme activity of the strains＇ culture fluid,titration was used with 1.1—6.6 U per milliliter.It seemed that B9,C1,E7,F12 had the potentiality as the biocatalysts.The 18S rDNA was amplified from 9 strains which had a relatively higher lipase activity,after the sequencing,BLAST and phylogenetic analysis showed that they were close to Candida.,Rhodotorula.,Trichosporon..Some physiological and biochemical methods were used to prove that the results were congruent with the 18 s rDNA analysis except H4 and H8.