We isolated and characterized a possible regulatory gene, designated actX gene, from Actinobacillus actinomyctemcomitans Y4, which defined the Actinobacillus pleuropneumoniae hlyX-like regulatory gene. DNA sequence analysis for plasmid clone pKM317 containing a 1.6-kb DNA insert indicated an open reading frame encoding a polypeptide of 257 amino acid residues. Analysis of the deduced amino acid sequence showed the presence of five characteristic cysteine residues in the N-terminal region and a putative DNA binding residue in the C-terminal region, indicating that actX might belong to a regulatory gene family. Escherichia coli DH5α and a mutant strain JRG1728 transformed by plasmid carrying actX manifested apparent hemolytic activity on sheep blood agar and grew anaerobically, although the original strains did not. (C) 2000 Editions scientifiques et medicales Elsevier SAS.
- Actinobacillus actinomycetemcomitans
- HlyX-like gene
- Regulatory gene
ASJC Scopus subject areas
- Applied Microbiology and Biotechnology