The integrase family of site‐specific recombinases: regional similarities and global diversity

• Published in: The EMBO journal Vol. 5; no. 2; pp. 433 - 440
• Main Authors: Argos, P., Landy, A., Abremski, K., Egan, J.B., Haggard‐Ljungquist, E., Hoess, R.H., Kahn, M.L., Kalionis, B., Narayana, S.V., Pierson, L.S.
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group 01-02-1986
• Subjects: Amino Acid Sequence; Bacteriophage lambda - enzymology; Biological and medical sciences; Coliphages - enzymology; DNA Helicases - genetics; DNA Nucleotidyltransferases - genetics; Fundamental and applied biological sciences. Psychology; Integrases; Microbiology; Protein Conformation; Replicative cycle, interference, host-virus relations, pathogenicity, miscellaneous strains; Species Specificity; Virology; Virus; Proteins; Lysogeny; Molecular integration; Bactériophage; Homology; Primary structure; Comparative study
• ISSN: 0261-4189; 1460-2075
• DOI: 10.1002/j.1460-2075.1986.tb04229.x

A combination of two methods for detecting distant relationships in protein primary sequences was used to compare the site‐specific recombination proteins encoded by bacteriophage lambda, phi 80, P22, P2, 186, P4 and P1. This group of proteins exhibits an unexpectedly large diversity of sequences. Despite this diversity, all of the recombinases can be aligned in their C‐terminal halves. A 40‐residue region near the C terminus is particularly well conserved in all the proteins and is homologous to a region near the C terminus of the yeast 2 mu plasmid Flp protein. This family of recombinases does not appear to be related to any other site‐specific recombinases. Three positions are perfectly conserved within this family: histidine, arginine and tyrosine are found at respective alignment positions 396, 399 and 433 within the well‐conserved C‐terminal region. We speculate that these residues contribute to the active site of this family of recombinases, and suggest that tyrosine‐433 forms a transient covalent linkage to DNA during strand cleavage and rejoining.