当前位置： SCI文献检索 > MOLECULAR MICROBIOLOGY期刊下所有文献 > Molecular basis of intercellular adhesion in the biofilm-forming Staphylococcus epidermidis.

Molecular basis of intercellular adhesion in the biofilm-forming Staphylococcus epidermidis.

Abstract：

:The Staphylococcus epidermidis genes icaABC are involved in the synthesis of the polysaccharide intercellular adhesin (PIA), which is located mainly on the cell surface, as shown by immunofluorescence studies with PIA-specific antiserum. PIA was shown to be a linear beta-1,6-linked glucosaminoglycan composed of at least 130 2-deoxy-2-amino-D-glucopyranosyl residues of which 80-85% are N-acetylated, the rest being non-N-acetylated and positively charged. A transposon insertion in the icaABC gene cluster (ica, intercellular adhesion) led to the loss of several traits, such as the ability to form a biofilm on a polystyrene surface, cell aggregation, and PIA production. The mutant could be complemented by transformation with the icaABC-carrying plasmid pCN27. Transfer of pCN27 into the heterologous host Staphylococcus carnosus led to the formation of large cell aggregates, the formation of a biofilm on a glass surface, and PIA expression. The nucleotide sequence of icaABC suggests that the three genes are organized in an operon and that they are co-transcribed from the mapped icaA promoter. IcaA contains four potential transmembrane helices, indicative of a membrane location. The deduced IcaA sequence shows similarity to those of polysaccharide-polymerizing enzymes, the most pronounced being with a Rhizobium meliloti N-acetylglucosaminyltransferase involved in lipo-chitin biosynthesis (22.5% overall identity and 37.4% overall similarity). This similarity suggests that IcaA has N-acetylglucosaminyltransferase activity in the formation of the beta-1, 6-linked N-acetyl-D-glucosaminyl polymer. IcaB is secreted into the medium and contains a typical signal peptide. IcaC is hydrophobic and contains six predicted transmembrane helices distributed over its entire length, typical for an integral membrane protein. Neither IcaB nor IcaC shares similarity with known proteins, and their function is unknown. Inactivation of icaA, icaB, or icaC in pCN27 led to the complete loss of the intercellular adhesion phenotype in S. carnosus, suggesting that all three genes are involved in intercellular adhesion, PIA expression, and translocation.

journal_name

Mol Microbiol

journal_title

Molecular microbiology

authors

Heilmann C,Schweitzer O,Gerke C,Vanittanakom N,Mack D,Götz F

doi

10.1111/j.1365-2958.1996.tb02548.x

subject

Has Abstract

pub_date

1996-06-01 00:00:00

pages

1083-91

issue

eissn

0950-382X

issn

1365-2958

journal_volume

pub_type

杂志文章

在线工具

Molecular basis of intercellular adhesion in the biofilm-forming Staphylococcus epidermidis.