Title: | Analysis of functional domains of the Enterococcus faecalis pheromone-induced surface protein aggregation substance |
Address: | "Department of Microbiology, University of Minnesota Medical School, Minneapolis, Minnesota 55455, USA" |
DOI: | 10.1128/JB.183.19.5659-5667.2001 |
ISSN/ISBN: | 0021-9193 (Print) 1098-5530 (Electronic) 0021-9193 (Linking) |
Abstract: | "Pheromone-inducible aggregation substance (AS) proteins of Enterococcus faecalis are essential for high-efficiency conjugation of the sex pheromone plasmids and also serve as virulence factors during host infection. A number of different functions have been attributed to AS in addition to bacterial cell aggregation, including adhesion to host cells, adhesion to fibrin, increased cell surface hydrophobicity, resistance to killing by polymorphonuclear leukocytes and macrophages, and increased vegetation size in an experimental endocarditis model. Relatively little information is available regarding the structure-activity relationship of AS. To identify functional domains, a library of 23 nonpolar 31-amino-acid insertions was constructed in Asc10, the AS encoded by the plasmid pCF10, using the transposons TnlacZ/in and TnphoA/in. Analysis of these insertions revealed a domain necessary for donor-recipient aggregation that extends further into the amino terminus of the protein than previously reported. In addition, insertions in the C terminus of the protein also reduced aggregation. As expected, the ability to aggregate correlates with efficient plasmid transfer. The results also indicated that an increase in cell surface hydrophobicity resulting from AS expression is not sufficient to mediate bacterial aggregation" |
Keywords: | "Bacterial Adhesion Bacterial Proteins/*chemistry/genetics/*metabolism DNA Transposable Elements Enterococcus faecalis/*genetics/metabolism Flow Cytometry Mutagenesis, Insertional Pheromones/genetics/*pharmacology Plasmids/genetics Spectrophotometry/method;" |
Notes: | "MedlineWaters, C M Dunny, G M eng R01 GM049530/GM/NIGMS NIH HHS/ HL-51987/HL/NHLBI NIH HHS/ R01 HL051987/HL/NHLBI NIH HHS/ 5 T32 AI07421-5/AI/NIAID NIH HHS/ GM-49530/GM/NIGMS NIH HHS/ T32 AI007421/AI/NIAID NIH HHS/ Research Support, U.S. Gov't, P.H.S. 2001/09/07 J Bacteriol. 2001 Oct; 183(19):5659-67. doi: 10.1128/JB.183.19.5659-5667.2001" |