Methods of identifying an organism

Abstract

This disclosure features methods of identifying an organism. In certain embodiments, the invention provides methods of distinguishing virulent and non-virulent strains of Listeria monocytogenes.

1 - 9 . (canceled) 
     
     
         10 . A method of distinguishing virulent and low- or non-virulent strains of  Listeria monocytogenes,  the method comprising:
 obtaining a nucleic acid from  L. monocytogenes;      preparing an optical map of one or more restriction digests of the obtained nucleic acid; and   detecting an insertion that is at least 1 kb in size in a clpP gene of a genome of  L. monocytogenes,  wherein the insertion results in inactivation of the clpP gene, which is indicative of a low- or non-virulent strain of  L. monocytogenes.      
     
     
         11 . The method according to  claim 10 , wherein the nucleic acid is obtained from at least one sample type selected from the group consisting of: a food sample, an environmental sample, and a human tissue or body fluid sample. 
     
     
         12 . The method according to  claim 11 , wherein the environmental sample is selected from the group consisting of water, soil, sewage, and decaying vegetable matter. 
     
     
         13 . The method according to  claim 11 , wherein the tissue or body fluid is from a human having a disease selected from the group consisting of meningitis, gastroenteritis, and septicemia. 
     
     
         14 . The method according to  claim 10 , wherein the insertion is a 48.3 kb insertion. 
     
     
         15 . The method according to  claim 10 , wherein the  L. monocytogenes  is classified as a serotype 4b strain. 
     
     
         16 . The method according to  claim 10 , wherein the  L. monocytogenes  is classified as a serotype 1/2a strain. 
     
     
         17 . The method according to  claim 10 , wherein the  L. monocytogenes  low- or non-virulent strain is selected from the group consisting of L. monocytogenes BO43 or  L. monocytogenes  416. 
     
     
         18 . The method according to  claim 10 , wherein the  L. monocytogenes  virulent strain is selected from the group consisting of  L. monocytogenes  strain 4b F2365,  L. monocytogenes  strain EGD-e,  L. monocytogenes  strain A23,  L. monocytogenes  Clip81459 ′4b CLIP80459′.