Molecular cloning and characterization of clyA genes in various serotypes of Salmonella enterica.
Cytolysin A (ClyA) is a pore-forming hemolytic protein encoded by the clyA gene. It has been identified in Salmonella enterica serovars Typhi and Paratyphi A. To identify and characterize the clyA genes in various Salmonella enterica strains, 21 different serotypes of strains isolated from clinical specimens were presently examined. Full-length clyA genes were found in S. enterica serovar Brandenburg, Indiana, Panama, and Schwarzengrund strains by polymerase chain reaction amplification. The ClyA proteins from these four strains showed >97% amino acid identity to that of S. enterica serovar Typhi. Although all four serovars expressed detectable levels of ClyA as determined by Western blot analysis, they did not show a strong hemolytic effect on blood agar, indicating that ClyA may not be efficiently expressed or secreted. Escherichia coli transformed with clyA genes from the four serovars enhanced production of ClyA proteins and hemolytic activities to a level similar to S. enterica serovar Typhi ClyA. The present results suggest that ClyA may play a role in the pathogenesis of S. enterica serovar Brandenburg, Indiana, Panama and Schwarzengrund.
Department of Microbiology, Chonnam National University Medical School, Gwangju, Republic of Korea.
Lan Ji
LJ
Huang
Jinghua
J
Cui
Hong Hua
HH
Piao
Yeongjin
Y
Hong
Hyon E
HE
Choy
Phil Youl
PY
Ryu
D015153:Blotting, Western; D003001:Cloning, Molecular; D003603:Cytotoxins / Q000096:biosynthesis* / Q000235:genetics*; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004926:Escherichia coli / Q000235:genetics / Q000472:pathogenicity; D015870:Gene Expression; D006461:Hemolysis; D006801:Humans; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D012480:Salmonella Infections / Q000382:microbiology*; D019779:Salmonella enterica / Q000235:genetics / Q000302:isolation & purification / Q000472:pathogenicity*; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D037521:Virulence Factors / Q000096:biosynthesis* / Q000235:genetics*
D003603:Cytotoxins; D004269:DNA, Bacterial; D037521:Virulence Factors