Cloning and characterization of two novel DNases from Streptococcus pyogenes.
The proteins in the culture supernatant (exoproteins) from Streptococcus pyogenes serotype M1 were separated by two-dimensional gel electrophoresis, and their N-terminal amino acid sequences were determined. The amino acid sequences were compared to sequences in the S. pyogenes genome database. The coding sequence showed similarity to sequences of two genes, mf2-v ( mf2 variant) and mf3, which had sequence similarity to genes encoding mitogenic factor (MF); MF has DNase activity. The recombinant genes were expressed in Escherichia coli and the proteins were synthesized. Mf2-v and Mf3 had DNase activity. The activity of Mf2-v was localized to the C-terminal half of the protein. The mf3 gene was shown to be present in most clinically isolated strains of S. pyogenes tested, and the mf2gene was detected in 20% of the isolates. The products of the mf2 and mf3 genes in clinically isolated S. pyogenes strains were thus shown to be DNases.
Hasegawa
Tadao
T
Department of Molecular Bacteriology, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya 466-8550, Japan. hasegawa@med.nagoya-u.ac.jp
Torii
Keizo
K
Hashikawa
Shinnosuke
S
Iinuma
Yoshitsugu
Y
Ohta
Michio
M
D000595:Amino Acid Sequence; D001426:Bacterial Proteins; D003001:Cloning, Molecular; D003851:Deoxyribonucleases / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism; D008969:Molecular Sequence Data; D011994:Recombinant Proteins / Q000096:biosynthesis; D016415:Sequence Alignment; D012772:Shock, Septic / Q000382:microbiology; D013297:Streptococcus pyogenes / Q000201:enzymology* / Q000235:genetics / Q000302:isolation & purification
D001426:Bacterial Proteins; D011994:Recombinant Proteins; D003851:Deoxyribonucleases; C466259:mf2 protein, Streptococcus pyogenes; C466258:mf3 protein, S pyogenes