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PubMed · 9765793

The adc locus, which affects competence for genetic transformation in Streptococcus pneumoniae, encodes an ABC transporter with a putative lipoprotein homologous to a family of streptococcal adhesins.

A Dintilhac·J P Claverys
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Abstract

To identify new components involved in the phenomenon of transformation in Streptococcus pneumoniae, a library of potential mutants has been generated by random insertion of an erythromycin resistance gene. Transformation-deficient mutants were screened using an in situ colony transformation test. The adc locus, which was identified in this search, was cloned and sequenced. Sequence analysis revealed a putative operon of three ORFs (adcC, adcB and adcA) with homology to ATP-binding cassette (ABC) transport operons encoding streptococcal adhesins such as ScaA of S. gordonii and FimA of S. parasanguis. adcA can encode a lipoprotein of 313 amino acid residues containing a putative metal-binding site. The polypeptide shows about 30% sequence identity with ScaA and FimA. We discuss evidence which leads us to propose that AdcA, together with a set of 14 proteins including ScaA, FimA and homologous adhesins, defines a new family of external solute-binding proteins, cluster 9, specific for metals.

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ATP-Binding Cassette TransportersAmino Acid SequenceBacterial AdhesionBacterial ProteinsCloning, MolecularFimbriae ProteinsLipoproteinsMembrane ProteinsMetalsMolecular Sequence DataMutagenesis, InsertionalMutationOpen Reading FramesOperonPhylogenySequence Analysis, DNASequence Homology, Amino AcidSequence Homology, Nucleic AcidStreptococcus pneumoniaeTransformation, BacterialJournal ArticleResearch Support, Non-U.S. Gov't

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A Dintilhac, J P Claverys. 1997. The adc locus, which affects competence for genetic transformation in Streptococcus pneumoniae, encodes an ABC transporter with a putative lipoprotein homologous to a family of streptococcal adhesins.. https://doi.org/10.1016/s0923-2508(97)87643-7

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