Cloning and sequence analysis of the pfl gene encoding pyruvate formate-lyase from Streptococcus mutans.
We have isolated a sorbitol-negative mutant of Streptococcus mutans GS-5 following random mutagenesis with plasmid pVA891 clone banks. This mutant did not metabolize sorbitol anaerobically but did so aerobically. A 10-kb chromosomal DNA fragment flanking the pVA891 insertion was deleted in this mutant. The corresponding region from the parental strain GS-5 was then recovered by a marker rescue method with Escherichia coli. The pyruvate formate-lyase gene, pfl, was identified within a 3-kb PstI-XbaI fragment located in the middle of the deleted region of the chromosome, and its inactivation in S. mutans produced the same sorbitol-negative phenotype. Nucleotide sequence analysis of the pfl gene revealed a 2.3-kb open reading frame (ORF) preceded by potential ribosome-binding and promoter-like sequences. The ORF specified a putative protein of 775 amino acid residues with a calculated molecular weight of 87,533. The amino acid sequence deduced from the ORF exhibited significant similarity to that of the E. coli pfl gene.
Yamamoto
Y
Y
Department of Biochemistry, Tokyo Dental College, Chiba City, Japan.
Sato
Y
Y
Takahashi-Abbe
S
S
Abbe
K
K
Yamada
T
T
Kizaki
H
H
D000123:Acetyltransferases / Q000737:chemistry / Q000235:genetics*; D000595:Amino Acid Sequence; D001483:Base Sequence; D003001:Cloning, Molecular; D005798:Genes, Bacterial; D008969:Molecular Sequence Data; D009154:Mutation; D016366:Open Reading Frames; D013295:Streptococcus mutans / Q000201:enzymology* / Q000235:genetics
D000123:Acetyltransferases; C022560:formate C-acetyltransferase