Detection and typing of bacterial strains
View Patent ↗Methods for the detection and typing of bacterial strains from food products and dietary supplements, environmental samples, in vivo/in vitro samples, and for studying the natural diversity of the species are disclosed. Potential applications also include product development and/or detection and differentiation of new bacterial strains.
1. A method for detecting the presence of a Lactobacillus acidophilus in a sample, comprising:
a) obtaining a sample;
b) amplifying a region of DNA comprising repetitive sequences that are at least 86% identical to the repetitive sequence comprised in the intergenic region set forth in SEQ ID NO:1 in said sample, to create amplified DNA; and,
c) detecting said amplified DNA.
2. The method of claim 1 , wherein said amplifying is performed using at least one primer comprising a sequence consisting of the sequence provided in SEQ ID NO:49 or SEQ ID NO:50.
3. A method for typing a Lactobacillus acidophilus bacterial strain comprising:
a) obtaining a sample;
b) amplifying a region of DNA comprising repetitive sequences that are at least 86% identical to the repetitive sequences comprised in the intergenic region set forth in SEQ ID NO:1 in said sample to create amplified DNA; and
c) typing said bacterial strain based on said amplified DNA.
4. The method of claim 3 , wherein said sample is selected from the group consisting of a food product, a dietary supplement, an animal feed and an animal feed supplement.
5. The method of claim 3 , wherein said amplified DNA is obtained by PCR, and wherein said PCR is performed using at least one primer comprising SEQ ID NO:49 or SEQ ID NO:50.
6. The method of claim 3 , further comprising:
a) sequencing said amplified DNA to obtain sequencing results; and,
b) typing said bacterial strain based on said sequencing results.
7. A method for typing a Lactobacillus acidophilus bacterial strain comprising:
a) obtaining a sample comprising said Lactobacillus acidophilus bacterial strain;
b) amplifying a region of DNA comprising repetitive sequences that are at least 86% identical to the repetitive sequences comprised in the intergenic region set forth in SEQ ID NO:1 in said sample to create amplified DNA;
c) adding to said amplified DNA at least one restriction enzyme that recognizes one or more sites in said amplified DNA;
d) incubating said restriction enzyme with said amplified DNA for a time sufficient to form restriction fragments;
e) determining the number of said restriction fragments and their size; and
f) typing said bacterial strain based on said number and size of said restriction fragments.
8. The method of claim 7 , wherein said restriction enzyme is selected from the group consisting of AluI, Msel, and Tsp5091.