Open AccessEvaluation Of Methods for the Determination of O and K Antigens of an O2:K1(L) Strain of Escherichia Coli
Author(s) -
J.R. Deb,
E.G. Harry
Publication year - 1977
Publication title -
journal of medical microbiology/journal of medical microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.91
H-Index - 117
eISSN - 1473-5644
pISSN - 0022-2615
DOI - 10.1099/00222615-10-1-77
Subject(s) - antigen , agglutination (biology) , immunoelectrophoresis , escherichia coli , hemagglutination , immunodiffusion , microbiology and biotechnology , biology , strain (injury) , serology , chemistry , agar , enterobacteriaceae , bacteria , antibody , biochemistry , immunology , genetics , anatomy , gene
Tests made on ten colonies from a strain of Escherichia coli O2:K1 demonstrated that bacterial agglutination tests were reliable for identifying the O antigen of serogroup O2 but were unreliable for identifying the K1 antigen. The granular nature of K agglutination was not a reliable characteristic of the L type of K antigen. In contrast, indirect haemagglutination, immunodiffusion and immunoelectrophoresis tests with bacterial extracts gave consistent results with all colonies. The polysaccharide K1 antigen formed a long anodic precipitation line with two peaks, indicating its heterogenous nature, and partial fusion of this line with the O-antigen precipitation line suggested the presence of common serological determinants. In addition, a heat-labile protein antigen, possibly another K antigen, was identified by indirect haemagglutination tests and may have produced a short anodic precipitation line. The results also showed that the K1 antigen was still produced after storage of a culture for 12 years on Dorset-egg medium.