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PubMed · 7984095

A conserved DNA sequence is required for efficient gonococcal pilin antigenic variation.

L A Wainwright·K H Pritchard·H S Seifert
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Abstract

Antigenic variation of the Neisseria gonorrhoeae pilus occurs when a variant pilin sequence from a silent locus recombines into the expression locus by predominantly unidirectional, homologous recombination. At the 3' end of all pilin loci lies a conserved DNA sequence, called the Sma/Cla repeat, which has sequence similarity to several recombinase-binding sites, and therefore may be involved in pilin recombination. We have developed a novel reverse transcriptase/polymerase chain reaction (RT-PCR) assay for direct monitoring of pilin recombination, and both RT-PCR and phase variation were used to examine pilin recombination in a gonococcal strain that had had the pilE Sma/Cla repeat removed. Results from these experiments showed a decrease in pilin recombination when the Sma/Cla sequence was deleted from the expression locus, showing that a specialized site (Sma/Cla) is involved in efficient pilin recombination.

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Antigenic VariationAntigens, BacterialBacterial Outer Membrane ProteinsBacterial ProteinsBase SequenceBinding SitesDNA NucleotidyltransferasesDNA, BacterialFimbriae ProteinsFimbriae, BacterialGenes, BacterialIntegrasesMolecular Sequence DataMutagenesis, InsertionalNeisseria gonorrhoeaePolymerase Chain ReactionRecombinasesRecombination, GeneticRepetitive Sequences, Nucleic AcidSequence AlignmentSequence Homology, Nucleic AcidComparative StudyJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

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L A Wainwright, K H Pritchard, H S Seifert. 1994. A conserved DNA sequence is required for efficient gonococcal pilin antigenic variation.. https://doi.org/10.1111/j.1365-2958.1994.tb00403.x

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