[Comparison of Cj1136, Cj1138 and Cj1139 genes among Campylobacter jejuni strains].

OBJECTIVE: By sequenceing the Cj1136, Cj1138 and Cj1139 gene of Campylobacter jejuni (C. jejuni) strains associated with Guillain-Barré Syndrome (GBS), features of Cj1136, Cj1138 and Cj1139 gene were studied. Results were compared with the C. jejuni strain NCTC11168, to find the mutations in sequence of C. jejuni which inducing GBS and their polygenetic relationship was analyzed. METHODS: Three GBS-associated C. jejuni strains were isolated from stools of GBS patients from Hebei province who had been diagnosed as clinical AMAN pattern and electrophysiological tests were performed. After distilling and sequencing Cj1136, Cj1138 and Cj1139 genes, results were spliced and assembled into a complete sequence by the terminals overlapped with each other. Sequences of Cj1136, Cj1138 and Cj1139 genes were compared with NCTC11168, to find the mutations and gene feature. RESULTS: The Cj1136, Cj1138 and Cj1139 gene of the three GBS- associated C. jejuni strains were composed by 1173 base pairs, 1170 base pairs, 912 base pairs respectively. The alignment with the related sequence of NCTC11168 showed that there were two same mutations in the Cj1138 gene of the three C. jejuni stains. Data from phylogenetic analysis demonstrated that the three C. jejuni strains were genetically closed to NCTC11168, with the biggest phylogenetic distance between the three of them as 2.1%. CONCLUSION: When compared with NCTC11168 the Cj1138 gene of the three GBS-associated C. jejuni strains had the same mutations which might be related to the development of GBS. Relation between the variation and GBS-pathogenesis remained to be confirmed. The mutations found in the three C. jejuni strains established the foundation for exploring the biological characteristics of GBS-associated C. jejuni strains and demonstrated that the GBSassociated C. jejuni strains of Hebei province having its regional features.