Recombination in the ompA gene but not the omcB gene of Chlamydia contributes to serovar-specific differences in tissue tropism, immune surveillance, and persistence of the organism

• Published in: Journal of bacteriology 2001-10, Vol.183 (20), p.5997-6008
• Main Authors: Millman, K L, Tavaré, S, Dean, D
• Format: Article
• Language: English
• Subjects: Animals; Bacterial Outer Membrane Proteins - genetics; Bacteriology; Chlamydia - classification; Chlamydia - genetics; Chlamydia - immunology; Chlamydia - pathogenicity; Chlamydia Infections - immunology; Chlamydia Infections - microbiology; Chlamydia pneumoniae; Chlamydia psittaci; Chlamydia trachomatis; Chlamydia trachomatis - classification; Chlamydia trachomatis - genetics; Chlamydia trachomatis - immunology; Chlamydia trachomatis - pathogenicity; Chlamydophila pneumoniae - classification; Chlamydophila pneumoniae - genetics; Chlamydophila pneumoniae - immunology; Chlamydophila pneumoniae - pathogenicity; Chlamydophila psittaci - classification; Chlamydophila psittaci - genetics; Chlamydophila psittaci - immunology; Chlamydophila psittaci - pathogenicity; Chromosome Breakage; Genes; Genes, Bacterial; Genetic Linkage; Humans; Immune system; major outer membrane protein; Membranes; Molecular Sequence Data; omcB gene; ompA gene; outer membrane complex B protein; Phylogeny; Population Genetics and Evolution; Proteins; Recombination, Genetic; Serotyping; Species Specificity; Tissues
• ISSN: 0021-9193; 1098-5530
• DOI: 10.1128/JB.183.20.5997-6008.2001

Sequences of the major outer membrane protein (MOMP) gene (ompA) and the outer membrane complex B protein gene (omcB) from Chlamydia trachomatis, Chlamydia pneumoniae, and Chlamydia psittaci were analyzed for evidence of intragenic recombination and for linkage equilibrium. The Sawyer runs test, compatibility matrices, and index of association analyses provided substantial evidence that there has been a history of intragenic recombination at ompA including one instance of interspecies recombination between the C. trachomatis mouse pneumonitis strain and the C. pneumoniae horse N16 strain. Although none of these methods detected intragenic recombination within omcB, differences in divergence reported in earlier studies suggested that there has been intergenic recombination involving omcB, and the analyses presented in this study are consistent with this. For C. trachomatis, index-of-association analyses suggested a higher degree of recombination for C class than for B class strains and a higher degree of recombination in the downstream half of ompA. In concordance with these findings, many significant breakpoints were found in variable segments 3 and 4 of MOMP for the recombinant strains D/B120, G/UW-57, E/Bour, and LGV-98 identified in this study. We provide examples of how genetic diversity generated by repeated recombination in these regions may be associated with evasion of immune surveillance, serovar-specific differences in tissue tropism, and persistence.