Open AccessCysteine proteases as digestive enzymes in parasitic helminths
Author(s) -
Conor R. Caffrey,
Louise S. Goupil,
Karina M. Rebello,
John P. Dalton,
David W. Smith
Publication year - 2018
Publication title -
plos neglected tropical diseases
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.99
H-Index - 135
eISSN - 1935-2735
pISSN - 1935-2727
DOI - 10.1371/journal.pntd.0005840
Subject(s) - proteases , biology , caenorhabditis elegans , cysteine protease , parasite hosting , nematode , cathepsin , fasciola , cysteine , enzyme , fasciola hepatica , microbiology and biotechnology , helminths , biochemistry , zoology , gene , ecology , world wide web , computer science
We briefly review cysteine proteases (orthologs of mammalian cathepsins B, L, F, and C) that are expressed in flatworm and nematode parasites. Emphasis is placed on enzyme activities that have been functionally characterized, are associated with the parasite gut, and putatively contribute to degrading host proteins to absorbable nutrients [ 1 – 4 ]. Often, gut proteases are expressed as multigene families, as is the case with Fasciola [ 5 ] and Haemonchus [ 6 ], presumably expanding the range of substrates that can be degraded, not least during parasite migration through host tissues [ 5 ]. The application of the free-living planarian and Caenorhabditis elegans as investigative models for parasite cysteine proteases is discussed. Finally, because of their central nutritive contribution, targeting the component gut proteases with small-molecule chemical inhibitors and understanding their utility as vaccine candidates are active areas of research [ 7 ].