Format

Send to

Choose Destination
Proc Natl Acad Sci U S A. 2015 Jun 16;112(24):7478-83. doi: 10.1073/pnas.1507082112. Epub 2015 May 5.

Destructin-1 is a collagen-degrading endopeptidase secreted by Pseudogymnoascus destructans, the causative agent of white-nose syndrome.

Author information

1
Department of Pharmaceutical Chemistry.
2
Department of Microbiology and Immunology, Brown University, Providence, RI 02912.
3
Department of Biochemistry and Biophysics, Department of Microbiology and Immunology, and ajohnson@cgl.ucsf.edu Richard_Bennett@brown.edu.
4
Department of Biochemistry and Biophysics, Howard Hughes Medical Institute, University of California, San Francisco, San Francisco, CA 94012; and.
5
Department of Microbiology and Immunology, Brown University, Providence, RI 02912 ajohnson@cgl.ucsf.edu Richard_Bennett@brown.edu.

Abstract

Pseudogymnoascus destructans is the causative agent of white-nose syndrome, a disease that has caused the deaths of millions of bats in North America. This psychrophilic fungus proliferates at low temperatures and targets hibernating bats, resulting in their premature arousal from stupor with catastrophic consequences. Despite the impact of white-nose syndrome, little is known about the fungus itself or how it infects its mammalian host. P. destructans is not amenable to genetic manipulation, and therefore understanding the proteins involved in infection requires alternative approaches. Here, we identify hydrolytic enzymes secreted by P. destructans, and use a novel and unbiased substrate profiling technique to define active peptidases. These experiments revealed that endopeptidases are the major proteolytic activities secreted by P. destructans, and that collagen, the major structural protein in mammals, is actively degraded by the secretome. A serine endopeptidase, hereby-named Destructin-1, was subsequently identified, and a recombinant form overexpressed and purified. Biochemical analysis of Destructin-1 showed that it mediated collagen degradation, and a potent inhibitor of peptidase activity was identified. Treatment of P. destructans-conditioned media with this antagonist blocked collagen degradation and facilitated the detection of additional secreted proteolytic activities, including aminopeptidases and carboxypeptidases. These results provide molecular insights into the secretome of P. destructans, and identify serine endopeptidases that have the clear potential to facilitate tissue invasion and pathogenesis in the mammalian host.

KEYWORDS:

connective tissue; fungi; pathogenesis; peptidase; secretome

PMID:
25944934
PMCID:
PMC4475985
DOI:
10.1073/pnas.1507082112
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for HighWire Icon for PubMed Central
Loading ...
Support Center