Molecular and enzymatic characterization of betaC-S lyase in Streptococcus constellatus.
Oral Microbiol Immunol
; 23(3): 245-53, 2008 Jun.
Article
em En
| MEDLINE
| ID: mdl-18402612
ABSTRACT
BACKGROUND/AIMS:
Streptococcus anginosus and Streptococcus constellatus are frequently isolated from dental abscesses and other suppurative lesions. We previously reported that betaC-S lyase from a strain of S. anginosus produced significantly more hydrogen sulfide than betaC-S lyases from other streptococci. The purpose of this study was to establish the molecular and enzymatic features of the betaC-S lyase in S. constellatus and to elucidate whether this unique capacity is common to many strains of S. constellatus and S. anginosus.METHODS:
The capacity of crude extract to produce hydrogen sulfide was evaluated among 16 strains of S. constellatus, S. anginosus, and Streptococcus gordonii. The lcd gene encoding betaC-S lyase was cloned from the genomic DNA of each strain to compare the deduced amino acid sequences. The recombinant betaC-S lyases of three representative strains were purified and characterized.RESULTS:
Incubation of crude extracts from all strains of S. constellatus and S. anginosus with l-cysteine resulted in the production of a large amount of hydrogen sulfide. The primary sequence of betaC-S lyase was very similar among strains of S. constellatus and S. anginosus. The kinetic properties of the betaC-S lyases purified from S. constellatus resembled those for betaC-S lyases purified from S. anginosus. In contrast, the betaC-S lyases of S. constellatus and S. gordonii differed in terms of their hydrogen sulfide production, with the former producing much more.CONCLUSION:
A high level of hydrogen sulfide production, which appears to be a common feature in both S. constellatus and S. anginosus, may be associated with their abscess formation.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Liases de Carbono-Enxofre
/
Streptococcus constellatus
Limite:
Humans
Idioma:
En
Revista:
Oral Microbiol Immunol
Ano de publicação:
2008
Tipo de documento:
Article