TY - JOUR
T1 - Streptococcus pyogenes protein F promotes invasion of HeLa cells
AU - Okada, Nobuhiko
AU - Tatsuno, Ichiro
AU - Hanski, Emanuel
AU - Caparon, Michael
AU - Sasakawa, Chihiro
PY - 1998/11
Y1 - 1998/11
N2 - Although the Gram-positive bacterium Streptococcus pyogenes (group A streptococcus) has been considered an extracellular pathogen which adheres to human mucosal epithelium, the streptococcus possesses invasive capacity for cultured human epithelial cells. This study provides genetic and functional evidence supporting the conclusion that protein F is capable of mediating entry of S. pyogenes into HeLa cells. Using Tn916 insertion mutagenesis or an isogenic S. pyogenes strain with a defined mutation in the gene encoding protein F (prtF), it was observed that the invasive capacity was affected by the levels of surface-exposed protein F, but not by those of M protein. In addition, heterologous expression of protein F on Enterococcus faecalis conferred upon the bacteria an efficient invasive phenotype. Several assays demonstrated that both the fibronectin-binding domains of protein F, UR and RD2, were involved in host-cell invasion. In addition, coinfection experiments of HeLa cells with S. pyogenes and an Escherichia coli K-12 strain expressing an afimbrial adhesin AFA-I showed that the uptake of S. pyogenes did not permit internalization of the E. coli cells.
AB - Although the Gram-positive bacterium Streptococcus pyogenes (group A streptococcus) has been considered an extracellular pathogen which adheres to human mucosal epithelium, the streptococcus possesses invasive capacity for cultured human epithelial cells. This study provides genetic and functional evidence supporting the conclusion that protein F is capable of mediating entry of S. pyogenes into HeLa cells. Using Tn916 insertion mutagenesis or an isogenic S. pyogenes strain with a defined mutation in the gene encoding protein F (prtF), it was observed that the invasive capacity was affected by the levels of surface-exposed protein F, but not by those of M protein. In addition, heterologous expression of protein F on Enterococcus faecalis conferred upon the bacteria an efficient invasive phenotype. Several assays demonstrated that both the fibronectin-binding domains of protein F, UR and RD2, were involved in host-cell invasion. In addition, coinfection experiments of HeLa cells with S. pyogenes and an Escherichia coli K-12 strain expressing an afimbrial adhesin AFA-I showed that the uptake of S. pyogenes did not permit internalization of the E. coli cells.
KW - Invasion
KW - Streptococcal infection
KW - Transposon mutagenesis
KW - Virulence
UR - http://www.scopus.com/inward/record.url?scp=0031766165&partnerID=8YFLogxK
U2 - 10.1099/00221287-144-11-3079
DO - 10.1099/00221287-144-11-3079
M3 - ???researchoutput.researchoutputtypes.contributiontojournal.article???
C2 - 9846743
AN - SCOPUS:0031766165
SN - 1350-0872
VL - 144
SP - 3079
EP - 3086
JO - Microbiology
JF - Microbiology
IS - 11
ER -