Abstract
Background & objectives: Group A Streptococcus, causative agent of several clinical manifestations codes for multiple protein invasins which help the bacterium to enter non-phagocytic cells. C5a peptidase (SCPA) is a surface protein conserved among different serotypes of M1 strain. The present study was taken up to study SCPA promoted fibronectin independent entry of GAS into epithelial cells. Methods: An isogenic 90226 emm1ΔAB (M1-) mutant was constructed with thermosensitive pGhost vector. This isogenic M1- mutant expressed SCPA on the surface as determined by Western blotting and immunofluorescence. Results: On preincubation with anti-SCPA serum, the isogenic M1- strain exhibited 54 per cent decreased invasion as compared to the bacteria incubated with control serum. Also, purified recombinant SCPA proteins blocked internalization of M1- streptococci into HEp-2 cells. The M1- strain invaded at the same efficiency in the presence or absence of fibronectin. Interpretation & conclusion: These results suggested that SCPA acted as a potential invasin of group A streptococcus and promoted invasion independent of fibronectin.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 44-47 |
| Number of pages | 4 |
| Journal | Indian Journal of Medical Research, Supplement |
| Volume | 119 |
| Issue number | MAY |
| State | Published - 2004 |
| Externally published | Yes |
Keywords
- C5a peptidase
- Fibronectin
- Group A streptococcus
- Invasion
- M1 strain
ASJC Scopus subject areas
- General Biochemistry, Genetics and Molecular Biology