Related Experiment Video
Updated: Aug 19, 2026

Molecular Evolution of the Tre Recombinase
Published on: May 29, 2008
Recombination among protein II genes of Neisseria gonorrhoeae generates new coding sequences and increases structural
T D Connell1, W J Black, T H Kawula
1Department of Microbiology and Immunology, University of North Carolina School of Medicine, Chapel Hill 27514.
Abstract:
Expression of Neisseria gonorrhoeae Protein II (P.II) is subject to phase variation and antigenic variation. The P.II proteins made by one strain possess both unique and conserved antigenic determinants. To study the mechanism of antigenic variation, we cloned several P.II genes, using as probes a panel of monoclonal antibodies (MAbs) specific for unique determinants. The DNA sequences of three P.II genes showed that they shared a conserved framework, with two short hypervariable (HV) regions being responsible for most of the differences among them. We demonstrated that unique epitopes recognized by the MAbs were at least partially encoded by one of the HV regions. Moreover, we found that reassortment of the two HV regions among P.II genes occurs, generating increased structural and antigenic variability in the P.II protein family.
Related Concept Videos
Viral Recombination
Genome Size and the Evolution of New Genes
Gene Conversion
Conservative Site-specific Recombination and Phase Variation
The recognition sites for Cre recombinase called LoxP...
Exon Recombination
Exon shuffling follows “splice frame rules.” Each exon has three reading...
Gene Conversion

