title: Sequence of the Streptococcus pneumoniae bacteriophage HB-3 amidase reveals high homology with the major host autolysin.
abstract: We have sequenced a DNA fragment containing the pneumococcal bacteriophage HB-3 hbl gene, which codes for the phage lytic amidase. A remarkable nucleotide similarity (87.1%) between the lytA gene, coding for the pneumococcal amidase, the major autolysin of Streptococcus pneumoniae, and the hbl gene was found. This similarity completely disappeared outside the open reading frames coding for both amidases. The hbl gene transformed amidase-deficient strains of S. pneumoniae to the wild-type phenotype, and Southern blotting experiments provided evidence for recombination between donor and recipient genes. A comprehensive evaluation of these and previous results on the peptidoglycan hydrolases of S. pneumoniae and its bacteriophages suggested that recombination mechanisms participate in the evolution of the genes coding for these enzymes.
authors.affiliation: Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Científicas, Madrid, Spain.
authors.forename: A
authors.initials: A
authors.lastname: Romero
authors.forename: R
authors.initials: R
authors.lastname: Lopez
authors.forename: P
authors.initials: P
authors.lastname: Garcia
mesh_terms: D000581:Amidohydrolases / Q000235:genetics*; D000595:Amino Acid Sequence; D001435:Bacteriophages / Q000201:enzymology / Q000235:genetics*; D001483:Base Sequence; D005075:Biological Evolution; D004926:Escherichia coli / Q000235:genetics; D005814:Genes, Viral; D005838:Genotype; D008969:Molecular Sequence Data; D009154:Mutation; D009238:N-Acetylmuramoyl-L-alanine Amidase / Q000235:genetics*; D010641:Phenotype; D010957:Plasmids; D015183:Restriction Mapping; D012689:Sequence Homology, Nucleic Acid; D013296:Streptococcus pneumoniae / Q000201:enzymology / Q000235:genetics*; D015678:Viral Structural Proteins / Q000235:genetics
chemical_list: D015678:Viral Structural Proteins; D000581:Amidohydrolases; D009238:N-Acetylmuramoyl-L-alanine Amidase