title: Sequence analysis of the cloned streptococcal cell surface antigen I/II.
abstract: The gene spa P (formerly designated as spa P1) encoding the Mr 185,000 surface antigen (I/II) of Streptococcus mutans, serotype c (NG5), has been sequenced. The gene (4683 bp) encodes a protein of 1561 amino acid residues including putative signal peptide (residues 1-38) and transmembrane (residues 1537-1556) sequences. The N-terminal region (60-550) has alanine-rich repeats and is predicted to be alpha-helical. However, the C-terminal region (800-1540) is proline-rich and favours an extended structure. Except for a short central variable region the sequences appear to be highly conserved for S. mutans serotype c. N-Terminal sequencing of separated antigen I and antigen II polypeptides suggests that the former represents the N-terminal and the latter the C-terminal portions of the intact antigen.
authors.affiliation: Department of Immunology, United Medical School of Guy's Hospital, London, England.
authors.forename: C
authors.initials: C
authors.lastname: Kelly
authors.forename: P
authors.initials: P
authors.lastname: Evans
authors.forename: L
authors.initials: L
authors.lastname: Bergmeier
authors.forename: S F
authors.initials: SF
authors.lastname: Lee
authors.forename: A
authors.initials: A
authors.lastname: Progulske-Fox
authors.forename: A C
authors.initials: AC
authors.lastname: Harris
authors.forename: A
authors.initials: A
authors.lastname: Aitken
authors.forename: A S
authors.initials: AS
authors.lastname: Bleiweis
authors.forename: T
authors.initials: T
authors.lastname: Lehner
mesh_terms: D000595:Amino Acid Sequence; D000942:Antigens, Bacterial / Q000096:biosynthesis / Q000235:genetics*; D000954:Antigens, Surface / Q000096:biosynthesis / Q000235:genetics*; D001426:Bacterial Proteins / Q000235:genetics*; D001483:Base Sequence; D003001:Cloning, Molecular; D004926:Escherichia coli / Q000378:metabolism*; D005798:Genes, Bacterial; D008562:Membrane Glycoproteins; D008969:Molecular Sequence Data; D010957:Plasmids; D016133:Polymerase Chain Reaction; D011994:Recombinant Proteins / Q000096:biosynthesis; D013295:Streptococcus mutans / Q000235:genetics*
chemical_list: D000942:Antigens, Bacterial; D000954:Antigens, Surface; D001426:Bacterial Proteins; D008562:Membrane Glycoproteins; D011994:Recombinant Proteins; C055764:S-layer proteins