Flint Joseph F, Angert Esther R
Department of Microbiology, Cornell University, Wing Hall Ithaca, NY 14853, United States.
J Microbiol Methods. 2005 May;61(2):235-43. doi: 10.1016/j.mimet.2004.12.002. Epub 2005 Jan 6.
A strain-specific assay was developed for the detection of viable Lactobacillus on cattle feed. The DNA sequences of the 16S rRNA gene and four different 16S/23S rRNA intergenic spacer regions (ISR) from Lactobacillus sp. HOFG1 were determined. Based on these sequences, a strain-specific primer was designed for the amplification of one of the ISRs. When combined with a Lactobacillus group primer, the polymerase chain reaction (PCR) assay detected only Lactobacillus sp. HOFG1 and not other closely related L. animalis or L. murinus strains. The feed assay uses a combination of enrichment culturing and PCR to detect and enumerate viable Lactobacillus sp. HOFG1 after its application onto cattle feed. The high degree of primer specificity and use of selective culturing allows for the detection of viable Lactobacillus which is useful in tracking bacteria applied to complex feed mixtures that contain a high background of endogenous bacteria.
开发了一种用于检测牛饲料中活的乳酸杆菌的菌株特异性检测方法。测定了乳酸杆菌属HOFG1菌株的16S rRNA基因和四个不同的16S/23S rRNA基因间隔区（ISR）的DNA序列。基于这些序列，设计了一种菌株特异性引物用于扩增其中一个ISR。当与乳酸杆菌属引物结合使用时，聚合酶链反应（PCR）检测方法仅能检测到乳酸杆菌属HOFG1菌株，而不能检测到其他密切相关的动物乳杆菌或鼠乳杆菌菌株。饲料检测方法采用富集培养和PCR相结合的方式，在将其应用于牛饲料后检测并计数活的乳酸杆菌属HOFG1菌株。高度的引物特异性和选择性培养的使用使得能够检测到活的乳酸杆菌，这对于追踪应用于含有高背景内源细菌的复杂饲料混合物中的细菌很有用。
