Purification of a chymotrypsin-like enzyme present on adult Schistosoma mansoni worms from infected mice and its characterization as a host carboxylesterase

Igetei, Joseph E.; Liddell, Susan; El-Faham, Marwa; Doenhoff, Michael J.

Abstract

A serine protease-like enzyme found in detergent extracts of Schistosoma mansoni adult worms perfused from infected mice has been purified from mouse blood and further characterized. The enzyme is approximately 85 kDa and hydrolyses N-acetyl-DL-phenylalanine β-naphthyl–ester, a chromogenic substrate for chymotrypsin-like enzymes. The enzyme from S. mansoni worms appears to be antigenically and enzymatically similar to a molecule that is present in normal mouse blood and so is seemingly host-derived. The enzyme was partially purified by depleting normal mouse serum of albumin using sodium chloride and cold ethanol, followed by repeated rounds of purification by one-dimensional sodium dodecyl sulphate polyacrylamide gel electrophoresis. The purified material was subjected to tandem mass spectrometry and its derived peptides found to belong to mouse carboxylesterase 1C. Its ability to hydrolyse α- or β-naphthyl acetates, which are general esterase substrates, has been confirmed. A similar carboxylesterase was purified and characterized from rat blood. Additional evidence to support identification of the enzyme as a carboxylesterase has been provided. Possible roles of the enzyme in the mouse host–parasite relationship could be to ease the passage of worms through the host's blood vessels and/or in immune evasion.

Citation

Igetei, J. E., Liddell, S., El-Faham, M., & Doenhoff, M. J. (2016). Purification of a chymotrypsin-like enzyme present on adult Schistosoma mansoni worms from infected mice and its characterization as a host carboxylesterase. Parasitology, 143(5), 646-657. https://doi.org/10.1017/S0031182016000184

• Journal Article Type: Article
• Acceptance Date: Jan 16, 2016
• Online Publication Date: Feb 29, 2016
• Publication Date: Apr 1, 2016
• Deposit Date: Feb 10, 2016
• Publicly Available Date: Feb 29, 2016
• Journal: Parasitology
• Print ISSN: 0031-1820
• Electronic ISSN: 1469-8161
• Publisher: Cambridge University Press
• Peer Reviewed: Peer Reviewed
• Volume: 143
• Issue: 5
• Pages: 646-657
• DOI: https://doi.org/10.1017/S0031182016000184
• Keywords: S. mansoni, host-derived enzyme, mice, carboxylesterase 1C, immune evasion
• Public URL: https://nottingham-repository.worktribe.com/output/777794
• Publisher URL: http://dx.doi.org/10.1017/S0031182016000184
• Additional Information: Copyright Cambridge University Press.