title: Monitoring ALS1 and ALS3 gene expression during in vitro Candida albicans biofilm formation under continuous flow conditions.
abstract: ALS1 and ALS3 encode cell-surface associated glycoproteins that are considered to be important for Candida albicans biofilm formation. The main goal of the present study was to monitor ALS1 and ALS3 gene expression during C. albicans biofilm formation (on silicone) under continuous flow conditions, using the Centers for Disease Control biofilm reactor (CDC reactor). For ALS1, we found few changes in gene expression until later stages of biofilm formation (72 and 96 h) when this gene appeared to be downregulated relative to the gene expression level in the start culture. We observed an induction of ALS3 gene expression in the initial stages of biofilm formation (0.5, 1, and 6 h), whereas at later stages, this gene was also downregulated relative to the gene expression level in the start culture. We also found that biofilms of an als3/als3 deletion mutant contained less filaments at several time points (1, 6, 24, and 48 h), although filamentation as such was not affected in this strain. Together, our data indicate an important role for ALS3 in the early phases of biofilm formation in the CDC reactor, probably related to adhesion of filaments, while the role of ALS1 is less clear.
authors.affiliation: Laboratory for Pharmaceutical Microbiology, Ghent University, Ghent, Belgium.
authors.forename: Heleen
authors.initials: H
authors.lastname: Nailis
authors.forename: Roosmarijn
authors.initials: R
authors.lastname: Vandenbroucke
authors.forename: Kelly
authors.initials: K
authors.lastname: Tilleman
authors.forename: Dieter
authors.initials: D
authors.lastname: Deforce
authors.forename: Hans
authors.initials: H
authors.lastname: Nelis
authors.forename: Tom
authors.initials: T
authors.lastname: Coenye
mesh_terms: D018441:Biofilms / Q000254:growth & development*; D019149:Bioreactors; D002176:Candida albicans / Q000166:cytology / Q000235:genetics*; D002448:Cell Adhesion; D005656:Fungal Proteins / Q000096:biosynthesis* / Q000235:genetics; D017353:Gene Deletion; D015966:Gene Expression Regulation, Fungal; D013997:Time Factors
chemical_list: C093538:ALS1 protein, Candida albicans; C113620:ALS3 protein, Candida albicans; D005656:Fungal Proteins