TY - JOUR
T1 - A novel subtilisin-like serine protease of Batrachochytrium dendrobatidis is induced by thyroid hormone and degrades antimicrobial peptides
AU - Thekkiniath, Jose C.
AU - Zabet-Moghaddam, Masoud
AU - San Francisco, Susan K.
AU - San Francisco, Michael J.
PY - 2013/6
Y1 - 2013/6
N2 - Batrachochytrium dendrobatidis (B. dendrobatidis), a chytrid fungus, is one of the major contributors to the global amphibian decline. The fungus infects both tadpoles and adult amphibians. Tadpoles are infected in their keratinized mouthparts, and infected adults exhibit hyperkeratosis and loss of righting reflex. Infections of adults may result in death from cardiac arrest in susceptible species. Thyroid hormone plays a key role in amphibian metamorphosis. The occurrence of B. dendrobatidis in tadpoles during metamorphosis may result in exposure of the fungus to host morphogens including TH. This exposure may induce gene expression in the fungus contributing to invasion and colonization of the host. Here, we demonstrate movement of fungal zoospores toward TH. Additionally, expression of a subtilisin-like serine protease is up-regulated in B. dendrobatidis cells exposed to TH. A gene encoding this protease was cloned from B. dendrobatidis and expressed in Escherichia coli. The protein was partially purified and characterized. The similarity between subtilases of human dermatophytes and the B. dendrobatidis subtilisin-like serine protease suggests the importance of this enzyme in B. dendrobatidis pathogenicity. Cleavage of frog skin antimicrobial peptides (AMPs) by this B. dendrobatidis subtilisin-like serine protease suggests a role for this enzyme in fungal survival and colonization.
AB - Batrachochytrium dendrobatidis (B. dendrobatidis), a chytrid fungus, is one of the major contributors to the global amphibian decline. The fungus infects both tadpoles and adult amphibians. Tadpoles are infected in their keratinized mouthparts, and infected adults exhibit hyperkeratosis and loss of righting reflex. Infections of adults may result in death from cardiac arrest in susceptible species. Thyroid hormone plays a key role in amphibian metamorphosis. The occurrence of B. dendrobatidis in tadpoles during metamorphosis may result in exposure of the fungus to host morphogens including TH. This exposure may induce gene expression in the fungus contributing to invasion and colonization of the host. Here, we demonstrate movement of fungal zoospores toward TH. Additionally, expression of a subtilisin-like serine protease is up-regulated in B. dendrobatidis cells exposed to TH. A gene encoding this protease was cloned from B. dendrobatidis and expressed in Escherichia coli. The protein was partially purified and characterized. The similarity between subtilases of human dermatophytes and the B. dendrobatidis subtilisin-like serine protease suggests the importance of this enzyme in B. dendrobatidis pathogenicity. Cleavage of frog skin antimicrobial peptides (AMPs) by this B. dendrobatidis subtilisin-like serine protease suggests a role for this enzyme in fungal survival and colonization.
KW - Amphibian decline
KW - Chemotaxis
KW - Host colonization
KW - Metamorphosis
KW - Pathogenicity
KW - Proteolytic activity
UR - http://www.scopus.com/inward/record.url?scp=84879737065&partnerID=8YFLogxK
U2 - 10.1016/j.funbio.2013.05.002
DO - 10.1016/j.funbio.2013.05.002
M3 - Article
C2 - 23809655
AN - SCOPUS:84879737065
VL - 117
SP - 451
EP - 461
JO - Fungal Biology
JF - Fungal Biology
SN - 1878-6146
IS - 6
ER -