Positively Selected Codons in Immune-Exposed Loops of the Vaccine Candidate OMP-P1 of Haemophilus influenzaeReport as inadecuate




Positively Selected Codons in Immune-Exposed Loops of the Vaccine Candidate OMP-P1 of Haemophilus influenzae - Download this document for free, or read online. Document in PDF available to download.

Journal of Molecular Evolution

, Volume 64, Issue 4, pp 411–422

First Online: 19 March 2007Received: 27 January 2006Accepted: 11 January 2007

Abstract

The high levels of variation in surface epitopes can be considered as an evolutionary hallmark of immune selection. New computational tools enable analysis of this variation by identifying codons that exhibit high rates of amino acid changes relative to the synonymous substitution rate. In the outer membrane protein P1 of Haemophilus influenzae, a vaccine candidate for nontypeable strains, we identified four codons with this attribute in domains that did not correspond to known or assumed B- and T-cell epitopes of OMP-P1. These codons flank hypervariable domains and do not appear to be false positives as judged from parsimony and maximum likelihood analyses. Some closely spaced positively selected codons have been previously considered part of a transmembrane domain, which would render this region unsuited for inclusion in a vaccine. Secondary structure analysis, three-dimensional structural database searches, and homology modeling using FadL of E. coli as a structural homologue, however, revealed that all positively selected codons are located in or near extracellular looping domains. The spacing and level of diversity of these positively selected and exposed codons in OMP-P1 suggest that vaccine targets based on these and conserved flanking residues may provide broad coverage in H. influenzae.

KeywordsHaemophilus influenzae Outer membrane proteinI Immune selection Structural information Epitope Vaccine Reviewing Editor: Dr. Rasmus Nielson

Electronic Supplementary MaterialThe online version of this article doi:10.1007-s00239-006-0021-2 contains supplementary material, which is available to authorized users.

Download fulltext PDF



Author: Ted H. M. Mes - Jos P. M. van Putten

Source: https://link.springer.com/







Related documents