Revised sequence of the Porphyromonas gingivalis prtT cysteine protease/hemagglutinin gene: homology with streptococcal pyrogenic exotoxin B/streptococcal proteinase.
The prtT gene from Porphyromonas gingivalis ATCC 53977 was previously isolated from an Escherichia coli clone possessing trypsinlike protease activity upstream of a region encoding hemagglutinin activity (J. Otogoto and H. Kuramitsu, Infect. Immun. 61;117-123, 1993). Subsequent molecular analysis of this gene has revealed that the PrtT protein is larger than originally reported, encompassing the hemagglutination region. Results of primer extension experiments indicate that the translation start site was originally misidentified. An alternate open reading frame of nearly 2.7 kb, which encodes a protein in the size range of 96 to 99 kDa, was identified. In vitro transcription-translation experiments confirm this size, and Northern (RNA) blot experiments indicate that the protease is translated from a 3.3-kb mRNA. Searching the EMBL protein database revealed that the amino acid sequence of the revised PrtT is similar to sequences of two related proteins from Streptococcus pyogenes. PrtT is 31% identical and 73% similar over 401 amino acids to streptococcal pyrogenic exotoxin B. In addition, it is 36% identical and 74% similar over 244 amino acids with streptococcal proteinase, which is closely related to streptococcal pyrogenic exotoxin B. The similarity is particularly high at the putative active site of streptococcal proteinase, which is similar to the active sites of the family of cysteine proteases. Thus, we conclude that PrtT is a 96- to 99-kDa cysteine protease and hemagglutinin with significant similarity to streptococcal enzymes.
Madden
T E
TE
Department of Dental Research, University of Rochester School of Medicine and Dentistry, New York 14642.
Clark
V L
VL
Kuramitsu
H K
HK
D000595:Amino Acid Sequence; D001426:Bacterial Proteins; D001483:Base Sequence; D003546:Cysteine Endopeptidases; D005098:Exotoxins / Q000235:genetics; D005798:Genes, Bacterial / Q000235:genetics*; D006388:Hemagglutinins / Q000235:genetics*; D008565:Membrane Proteins; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D016366:Open Reading Frames / Q000235:genetics; D016966:Porphyromonas gingivalis / Q000201:enzymology / Q000235:genetics*; D014176:Protein Biosynthesis; D012333:RNA, Messenger / Q000235:genetics; D015183:Restriction Mapping; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D012697:Serine Endopeptidases / Q000235:genetics*; D013297:Streptococcus pyogenes / Q000235:genetics; D014158:Transcription, Genetic; D014357:Trypsin / Q000235:genetics*
D001426:Bacterial Proteins; D005098:Exotoxins; D006388:Hemagglutinins; D008565:Membrane Proteins; D012333:RNA, Messenger; C117980:SpeA protein, Streptococcus pyogenes; C027951:erythrogenic toxin; D012697:Serine Endopeptidases; D014357:Trypsin; D003546:Cysteine Endopeptidases; C078912:prtT protein, Porphyromonas gingivalis