Dataset Information

Role of the Inducible Adhesin CpAls7 in Binding of Candida parapsilosis to the Extracellular Matrix under Fluid Shear.

ABSTRACT: The yeast Candida parapsilosis is an increasingly common cause of systemic fungal infections among immunocompromised individuals, including premature infants. Adhesion to host surfaces is an important step in pathogenesis, but this process has not been extensively studied in this organism. A microfluidics assay was developed to test the ability of C. parapsilosis to adhere to immobilized host extracellular matrix proteins under physiological fluid shear conditions. Growth in mammalian tissue culture medium at 37°C for 3 to 6 h led to the induction of an adhesive phenotype at shear forces of 1 to 5 dynes/cm² in some isolates of C. parapsilosis Glutamic acid, proline, and calcium appeared to be the minimally necessary requirements for increased adhesion in these assays. To determine whether genes homologous to the ALS gene family of C. albicans were important for the adhesive phenotype, the expression levels of 5 homologous C. parapsilosis genes were quantified by using quantitative PCR (qPCR) under conditions leading to increased adhesion. CPAR2_404800 (CpALS7) and CPAR2_404780 showed increased expression levels compared to those in control yeast. The extent of adhesion was variable among different isolates, and linear regression identified the expression of CpALS7 but not CPAR2_404780 as having a strong positive correlation with adhesion. A homozygous CpALS7 deletion strain was deficient in adhesion, whereas the expression of CpALS7 in Saccharomyces cerevisiae resulted in increased adhesion. Together, these data provide strong evidence that CpAls7 aids in the adherence of C. parapsilosis to the extracellular matrix under shear forces and support its previously reported role in virulence.

SUBMITTER: Neale MN

PROVIDER: S-EPMC5865022 | biostudies-literature | 2018 Apr

REPOSITORIES: biostudies-literature

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Role of the Inducible Adhesin CpAls7 in Binding of Candida parapsilosis to the Extracellular Matrix under Fluid Shear.

Neale Matthew N MN Glass Kyle A KA Longley Sarah J SJ Kim Denny J DJ Laforce-Nesbitt Sonia S SS Wortzel Jeremy D JD Shaw Sunil K SK Bliss Joseph M JM

Infection and immunity 20180322 4

The yeast <i>Candida parapsilosis</i> is an increasingly common cause of systemic fungal infections among immunocompromised individuals, including premature infants. Adhesion to host surfaces is an important step in pathogenesis, but this process has not been extensively studied in this organism. A microfluidics assay was developed to test the ability of <i>C. parapsilosis</i> to adhere to immobilized host extracellular matrix proteins under physiological fluid shear conditions. Growth in mammal ...[more]

PMID: 29378793

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Dataset Information

Role of the Inducible Adhesin CpAls7 in Binding of Candida parapsilosis to the Extracellular Matrix under Fluid Shear.

Publications

Role of the Inducible Adhesin CpAls7 in Binding of Candida parapsilosis to the Extracellular Matrix under Fluid Shear.

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