The occurrence of highly conserved amyloid-forming sequences in Candida albicans Als proteins (H. N. Otoo et al.
View Article and Find Full Text PDFAim: The significance of finding Candida species in heart blood cultures obtained at postmortem examination has never been studied. This article describes the findings of autopsy patients with postmortem candidaemia and it compares them with findings in autopsy patients with antemortem candidaemia.
Method: 23 patients with Candida species isolated from heart blood at autopsy were identified over a 10-year period.
Tandem repeat (TR) regions are common in yeast adhesins, but their structures are unknown, and their activities are poorly understood. TR regions in Candida albicans Als proteins are conserved glycosylated 36-residue sequences with cell-cell aggregation activity (J. M.
View Article and Find Full Text PDFElucidating the molecular mechanisms behind the strength and mechanics of cell adhesion proteins is of central importance in cell biology and offers exciting avenues for the identification of potential drug targets. Here we use single-molecule force spectroscopy to investigate the adhesive and mechanical properties of the widely expressed Als5p cell adhesion protein from the opportunistic pathogen Candida albicans . We show that the forces required to unfold individual tandem repeats of the protein are in the 150-250 pN range, both on isolated molecules and on live cells.
View Article and Find Full Text PDFCandida species are the 4th most common cause of nosocomial bloodstream infections in North America. It is not widely appreciated, however, that many of these infections are polymicrobial, that is, that bacteria and occasionally more than 1 species of Candida are present in the same blood culture bottle. Analysis of 2 groups of candidemic patients and a review of the literature were performed.
View Article and Find Full Text PDFCandida albicans occupies a microniche on mucosal surfaces where diverse microbial populations interact within a biofilm. Because C. albicans is intimately involved with other microbes in this environment we studied the interactions of C.
View Article and Find Full Text PDFCommensal and pathogenic states of Candida albicans depend on cell surface-expressed adhesins, including those of the Als family. Mature Als proteins consist of a 300-residue N-terminal region predicted to have an immunoglobulin (Ig)-like fold, a 104-residue conserved Thr-rich region (T), a central domain of a variable number of tandem repeats (TR) of a 36-residue Thr-rich sequence, and a heavily glycosylated C-terminal Ser/Thr-rich stalk region, also of variable length (N. K.
View Article and Find Full Text PDFAntimicrob Agents Chemother
November 2004
Candida albicans adheres to host tissue and then proliferates in order to establish a commensal as well as a pathogenic state. Specific adherence to proteins is provided by several surface adhesins of Candida. Two well-studied proteins, Als1p and Als5p, do not require energy for adherence to occur (dead as well as living cells adhere) and have a multiplier effect of cell-cell aggregation that mediates the formation of microcolonies of Candida cells.
View Article and Find Full Text PDFCandida albicans maintains both commensal and pathogenic states in humans. Both states are dependent on cell surface-expressed adhesins, including those of the Als family. Heterologous expression of Als5p at the surface of Saccharomyces cerevisiae results in Als5p-mediated adhesion to various ligands, followed by formation of multicellular aggregates.
View Article and Find Full Text PDFCandida albicans and Saccharomyces cerevisiae expressing the adhesins Als5p or Als1p adhere to immobilized peptides and proteins that possess appropriate sequences of amino acids in addition to a sterically accessible peptide backbone. In an attempt to further define the nature of these targets, we surveyed the ability of yeast cells to adhere to 90- micro m-diameter polyethylene glycol beads coated with a 7-mer peptide from a library of 19(7) unique peptide-beads. C.
View Article and Find Full Text PDFMicrobiology (Reading)
February 2004
Candida albicans displays a high degree of specificity in selecting and adhering to targets in vivo. The features of target recognition are poorly understood and likely to involve more than the mere chemical composition of the ligand. Using an adherence assay in which protein and peptide ligands are covalently coupled to magnetic beads, the authors have previously described a new adherence mechanism in C.
View Article and Find Full Text PDFSaccharomyces cerevisiae transformed with Candida albicans ALA1/ALS5 exhibits adherence properties similar to C. albicans. Adherence of the fungi to immobilized proteins involves hydrogen bonds, is stable to shear forces, and is resistant to competition from various biological molecules.
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