title: The MP65 gene is required for cell wall integrity, adherence to epithelial cells and biofilm formation in Candida albicans.
abstract: BACKGROUND
  The MP65 gene of Candida albicans (orf19.1779) encodes a putative β-glucanase mannoprotein of 65 kDa, which plays a main role in a host-fungus relationship, morphogenesis and pathogenicity. In this study, we performed an extensive analysis of a mp65Δ mutant to assess the role of this protein in cell wall integrity, adherence to epithelial cells and biofilm formation.
  
  
  RESULTS
  The mp65Δ mutant showed a high sensitivity to a range of cell wall-perturbing and degrading agents, especially Congo red, which induced morphological changes such as swelling, clumping and formation of hyphae. The mp65Δ mutant showed an activation of two MAPKs (Mkc1p and Cek1p), a high level of expression of two stress-related genes (DDR48 and SOD5), and a modulated expression of β-glucan epitopes, but no gross changes in cell wall polysaccharide composition. Interestingly, the mp65Δ mutant displayed a marked reduction in adhesion to BEC and Caco-2 cells and severe defects in biofilm formation when compared to the wild type. All of the mentioned properties were totally or partially recovered in a revertant strain, demonstrating the specificity of gene deletion.
  
  
  CONCLUSIONS
  We demonstrate that the MP65 gene of Candida albicans plays a significant role in maintaining cell wall integrity, as well as in adherence to epithelia and biofilm formation, which are major virulence attributes of this fungus.
authors.affiliation: Department of Infectious, Parasitic and Immuno-mediated Diseases, Istituto Superiore di Sanità, Rome, 00161, Italy. silvia.sandini@iss.it
authors.forename: Silvia
authors.initials: S
authors.lastname: Sandini
authors.forename: Annarita
authors.initials: A
authors.lastname: Stringaro
authors.forename: Silvia
authors.initials: S
authors.lastname: Arancia
authors.forename: Marisa
authors.initials: M
authors.lastname: Colone
authors.forename: Francesca
authors.initials: F
authors.lastname: Mondello
authors.forename: Susanna
authors.initials: S
authors.lastname: Murtas
authors.forename: Antonietta
authors.initials: A
authors.lastname: Girolamo
authors.forename: Nicolina
authors.initials: N
authors.lastname: Mastrangelo
authors.forename: Flavia
authors.initials: F
authors.lastname: De Bernardis
mesh_terms: D000935:Antifungal Agents / Q000633:toxicity; D018441:Biofilms / Q000254:growth & development*; D018938:Caco-2 Cells; D002176:Candida albicans / Q000254:growth & development / Q000472:pathogenicity* / Q000502:physiology*; D002448:Cell Adhesion; D002473:Cell Wall / Q000737:chemistry / Q000502:physiology*; D003224:Congo Red / Q000633:toxicity; D004847:Epithelial Cells / Q000382:microbiology*; D017353:Gene Deletion; D006026:Glycoside Hydrolases / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D011134:Polysaccharides / Q000378:metabolism
chemical_list: D000935:Antifungal Agents; D011134:Polysaccharides; D003224:Congo Red; D006026:Glycoside Hydrolases