Click here to close Hello! We notice that you are using Internet Explorer, which is not supported by Xenbase and may cause the site to display incorrectly. We suggest using a current version of Chrome, FireFox, or Safari.
XB-ART-51949
Infect Immun December 1, 2015; 83 (12): 4565-70.

Immunomodulatory metabolites released by the frog-killing fungus Batrachochytrium dendrobatidis.

Rollins-Smith LA , Fites JS , Reinert LK , Shiakolas AR , Umile TP , Minbiole KP .


Abstract
Batrachochytrium dendrobatidis is a fungal pathogen in the phylum Chytridiomycota that causes the skin disease chytridiomycosis. Chytridiomycosis is considered an emerging infectious disease linked to worldwide amphibian declines and extinctions. Although amphibians have well-developed immune defenses, clearance of this pathogen from the skin is often impaired. Previously, we showed that the adaptive immune system is involved in the control of the pathogen, but B. dendrobatidis releases factors that inhibit in vitro and in vivo lymphocyte responses and induce lymphocyte apoptosis. Little is known about the nature of the inhibitory factors released by this fungus. Here, we describe the isolation and characterization of three fungal metabolites produced by B. dendrobatidis but not by the closely related nonpathogenic chytrid Homolaphlyctis polyrhiza. These metabolites are methylthioadenosine (MTA), tryptophan, and an oxidized product of tryptophan, kynurenine (Kyn). Independently, both MTA and Kyn inhibit the survival and proliferation of amphibian lymphocytes and the Jurkat human T cell leukemia cell line. However, working together, they become effective at much lower concentrations. We hypothesize that B. dendrobatidis can adapt its metabolism to release products that alter the local environment in the skin to inhibit immunity and enhance the survival of the pathogen.

PubMed ID: 26371122
PMC ID: PMC4645405
Article link: Infect Immun



References [+] :
Albers, Metabolic characteristics and importance of the universal methionine salvage pathway recycling methionine from 5'-methylthioadenosine. 2009, Pubmed