利用16S rDNA序列及tuf-RFLP鉴定蒙古国发酵乳中的乳酸菌

摘要

One hundred and ten strains of lactic acid bacteria (LAB) isolated from twenty five samples of naturally fermented yoghurt in Dza-vhan of Mongolia were classified by 16S rDNA sequence analysis and tuf- RFLP. They were preliminary identified as Streptococcus thermophilus (41 strains), Lactobacillus helvetkus (40 strains), Lactobarillus delbrueckii subsp. Bulgaricus (11 strains), Lactobadllus fermentum (2 strains), Leuconostoc mesenteroides subsp. Mesenteroides (2 strains), Lactococcus lactis subsp. Lactis (1 strain) and Lactobadllus casei group (12 strains) by 16S rDNA sequence analysis. However, the 16S rDNA sequence of Lactobadllus casei group existed very small difference, tuf-RFLP was used to confirm results given by 16S rDNA sequencing. The tuf- RFLP profile pattern revealed that the twelve strains were accurately identified as Lactobadllus casei.%运用16S rDNA序列分析和tuf-RFLP技术对采于蒙古国扎布汗省的25份发酵乳样中分离出的110株乳酸菌进行鉴定.首先将分离的110株乳酸菌的16S rRNA基因进行扩增,测序并构建系统发育树,初步鉴定为41株嗜热链球菌,40株瑞士乳杆菌,11株德氏乳杆菌保加利亚亚种,2株发酵乳杆菌,1株乳明串珠菌,2株肠膜明串肠膜亚种,1株乳酸乳球乳酸亚种和12株属于干酪族的菌株.由于干酪乳杆菌族的16S rDNA序列差异很小,故采用tuf-RFLP 技术对这12株进行了进一步的验证,通过分离菌株与模式菌株tuf-RFLP图谱的比较分析,结果表明这12株菌均为干酪乳杆菌.