Antigenic variation among group A streptococcal M proteins. Nucleotide sequence of the serotype 5 M protein gene and its relationship with genes encoding types 6 and 24 M proteins.
The 1479-base pair (bp) nucleotide sequence of the serotype 5 M protein gene (smp5) from Streptococcus pyogenes contains three distinct types of tandemly repeated sequences, designated A, B, and C. Repeat A (21 bp x 6, in the 5'-half of smp5), shares no homology with the types 6 or 24 M protein genes (Hollingshead, S. K., Fischetti, V. A., and Scott, J. R. (1986) J. Biol. Chem. 261, 1677-1686; Mouw, A. R., Beachey, E. H., and Burdett, V. (1988) J. Bacteriol., in press). Repeat B (75 bp x 3.6, in the center of smp5) is also present in the M6, but not in the M24 gene. Repeat C (105 bp x 2.7, just distal to the B repeats) shares homology with repeats in both the M6 and M24 genes. All three genes share extensive homology in their 3'-halves and in 5' sequences encoding the N-terminal signal peptides, but between these two regions there are highly variable sequences that are responsible for antigenic diversity. These relationships suggest that both intergenic and intragenic recombination has occurred during the evolution of distinct M protein serotypes. All three M proteins contain conserved hydrophobic and proline-rich sequences at their C-terminal ends, suggestive of a membrane anchor and a peptidoglycan spanning region.
Miller
L
L
Department of Microbiology, Medical School, University of Newcastle upon Tyne, United Kingdom.
Gray
L
L
Beachey
E
E
Kehoe
M
M
D000595:Amino Acid Sequence; D000940:Antigenic Variation; D000942:Antigens, Bacterial / Q000235:genetics / Q000276:immunology; D001425:Bacterial Outer Membrane Proteins; D001426:Bacterial Proteins / Q000235:genetics* / Q000276:immunology; D001483:Base Sequence; D002352:Carrier Proteins; D003001:Cloning, Molecular; D004926:Escherichia coli / Q000235:genetics; D008969:Molecular Sequence Data; D021382:Protein Sorting Signals / Q000235:genetics; D011995:Recombination, Genetic; D012091:Repetitive Sequences, Nucleic Acid; D012689:Sequence Homology, Nucleic Acid; D013297:Streptococcus pyogenes / Q000235:genetics* / Q000276:immunology
D000942:Antigens, Bacterial; D001425:Bacterial Outer Membrane Proteins; D001426:Bacterial Proteins; D002352:Carrier Proteins; D021382:Protein Sorting Signals; C014689:streptococcal M protein