Expression in Escherichia coli and sequence analysis of the listeriolysin O determinant of Listeria monocytogenes.
To evaluate the role of hemolysin production in the virulence of Listeria monocytogenes, we have undertaken the analysis of the chromosomal region containing hlyA, the gene coding for listeriolysin O. A recombinant cosmid, conferring a hemolytic phenotype to Escherichia coli, was shown to express listeriolysin O, by immunoblotting with a specific antiserum against listeriolysin O. The presence of hlyA on the cosmid was demonstrated by DNA hybridization with a probe previously shown to contain part of hlyA. The complete nucleotide sequence of hlyA has been determined. The deduced protein sequence reveals the presence of a putative 25-amino-acid signal sequence: the secreted form of listeriolysin O would have 504 amino acids, in agreement with the molecular weight of purified listeriolysin O (58,000). The protein sequence is highly homologous to those of streptolysin O and pneumolysin. A peptide of 11 amino acids conserved in the three proteins contains the unique cysteine known to be essential for lytic activity. By DNA-DNA hybridization, the listeriolysin O gene was detected in all L. monocytogenes strains tested, even in the nonhemolytic type strain. The gene was absent in other species of the genus Listeria.
D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000235:genetics*; D001427:Bacterial Toxins / Q000235:genetics*; D001483:Base Sequence; D003001:Cloning, Molecular; D004269:DNA, Bacterial / Q000235:genetics; D004926:Escherichia coli / Q000235:genetics; D005798:Genes, Bacterial; D006360:Heat-Shock Proteins; D006460:Hemolysin Proteins / Q000235:genetics*; D008089:Listeria monocytogenes / Q000235:genetics*; D008969:Molecular Sequence Data; D013045:Species Specificity; D013301:Streptolysins / Q000235:genetics
D001426:Bacterial Proteins; D001427:Bacterial Toxins; D004269:DNA, Bacterial; D006360:Heat-Shock Proteins; D006460:Hemolysin Proteins; D013301:Streptolysins; C032290:plY protein, Streptococcus pneumoniae; C025964:streptolysin O; C038705:hlyA protein, Listeria monocytogenes