Production of congopain, the major cysteine protease of Trypanosoma (Nannomonas) congolense, in Pichia pastoris reveals unexpected dimerization at physiological Ph

African animal trypanosomosis (nagana) is arguably the most important parasitic disease affecting livestock in sub-Saharan Africa. Since none of the existing control measures are entirely satisfactory, vaccine development is being actively pursued. However, due to antigenic variation, the quest for...

Full description

Bibliographic Details
Main Authors: Boulange, A.F., Khamadi, S.A., Pillay, D., Coetzer, T.H.T., Authié, Edith
Format: Journal Article
Language:Inglés
Published: Elsevier 2011
Subjects:
Online Access:https://hdl.handle.net/10568/2416
_version_ 1855515820000542720
author Boulange, A.F.
Khamadi, S.A.
Pillay, D.
Coetzer, T.H.T.
Authié, Edith
author_browse Authié, Edith
Boulange, A.F.
Coetzer, T.H.T.
Khamadi, S.A.
Pillay, D.
author_facet Boulange, A.F.
Khamadi, S.A.
Pillay, D.
Coetzer, T.H.T.
Authié, Edith
author_sort Boulange, A.F.
collection Repository of Agricultural Research Outputs (CGSpace)
description African animal trypanosomosis (nagana) is arguably the most important parasitic disease affecting livestock in sub-Saharan Africa. Since none of the existing control measures are entirely satisfactory, vaccine development is being actively pursued. However, due to antigenic variation, the quest for a conventional vaccine has proven elusive. As a result, we have sought an alternative ‘anti-disease vaccine approach’, based on congopain, a cysteine protease of Trypanosoma congolense, which was shown to have pathogenic effects in vivo. Congopain was initially expressed as a recombinant protein in bacterial and baculovirus expression systems, but both the folding and yield obtained proved inadequate. Hence alternative expression systems were investigated, amongst which Pichia pastoris proved to be the most suitable. We report here the expression of full length, and C-terminal domain-truncated congopain in the methylotrophic yeast P. pastoris. Differences in yield were observed between full length and truncated proteins, the full length producing 2 to 4 mg of protein per litre of culture, while the truncated form produced 20 to 30 mg/l. The protease was produced as a proenzyme, but underwent spontaneous activation when acidified (pH< 5). To investigate whether this activation was due to autolysis, we produced an inactive mutant (active site Cys→Ala) by site-directed mutagenesis. The mutant form was produced at a much higher rate, up to 100 mg/l culture, as a proenzyme. It did not undergo spontaneous cleavage of the propeptide when subjected to acidic pH suggesting an autocatalytic process of activation for congopain. These recombinant proteins displayed a very unusual feature for cathepsin L-like proteinases, i.e. complete dimerisation at pH > 6, and by reversibly monomerising at acidic pH < 5. This attribute is of utmost importance in the context of an anti-disease vaccine, given that the epitopes recognised by the sera of trypanosome-infected trypanotolerant cattle appear dimer-specific.
format Journal Article
id CGSpace2416
institution CGIAR Consortium
language Inglés
publishDate 2011
publishDateRange 2011
publishDateSort 2011
publisher Elsevier
publisherStr Elsevier
record_format dspace
spelling CGSpace24162025-06-13T04:20:11Z Production of congopain, the major cysteine protease of Trypanosoma (Nannomonas) congolense, in Pichia pastoris reveals unexpected dimerization at physiological Ph Boulange, A.F. Khamadi, S.A. Pillay, D. Coetzer, T.H.T. Authié, Edith trypanosoma congolense cysteine protease trypanosomiasis animal diseases livestock biotechnology African animal trypanosomosis (nagana) is arguably the most important parasitic disease affecting livestock in sub-Saharan Africa. Since none of the existing control measures are entirely satisfactory, vaccine development is being actively pursued. However, due to antigenic variation, the quest for a conventional vaccine has proven elusive. As a result, we have sought an alternative ‘anti-disease vaccine approach’, based on congopain, a cysteine protease of Trypanosoma congolense, which was shown to have pathogenic effects in vivo. Congopain was initially expressed as a recombinant protein in bacterial and baculovirus expression systems, but both the folding and yield obtained proved inadequate. Hence alternative expression systems were investigated, amongst which Pichia pastoris proved to be the most suitable. We report here the expression of full length, and C-terminal domain-truncated congopain in the methylotrophic yeast P. pastoris. Differences in yield were observed between full length and truncated proteins, the full length producing 2 to 4 mg of protein per litre of culture, while the truncated form produced 20 to 30 mg/l. The protease was produced as a proenzyme, but underwent spontaneous activation when acidified (pH< 5). To investigate whether this activation was due to autolysis, we produced an inactive mutant (active site Cys→Ala) by site-directed mutagenesis. The mutant form was produced at a much higher rate, up to 100 mg/l culture, as a proenzyme. It did not undergo spontaneous cleavage of the propeptide when subjected to acidic pH suggesting an autocatalytic process of activation for congopain. These recombinant proteins displayed a very unusual feature for cathepsin L-like proteinases, i.e. complete dimerisation at pH > 6, and by reversibly monomerising at acidic pH < 5. This attribute is of utmost importance in the context of an anti-disease vaccine, given that the epitopes recognised by the sera of trypanosome-infected trypanotolerant cattle appear dimer-specific. 2011-01 2010-09-12T09:19:04Z 2010-09-12T09:19:04Z Journal Article https://hdl.handle.net/10568/2416 en Limited Access Elsevier Boulangé, A.F.; Khamadi, S.A.; Pillay, D.; Coetzer, T.H.T. and Authié, E. 2011. Production of congopain, the major cysteine protease of Trypanosoma (Nannomonas) congolense, in Pichia pastoris reveals unexpected dimerisation at physiological Ph. Protein Expression and Purification 75(1):95-103.
spellingShingle trypanosoma congolense
cysteine protease
trypanosomiasis
animal diseases
livestock
biotechnology
Boulange, A.F.
Khamadi, S.A.
Pillay, D.
Coetzer, T.H.T.
Authié, Edith
Production of congopain, the major cysteine protease of Trypanosoma (Nannomonas) congolense, in Pichia pastoris reveals unexpected dimerization at physiological Ph
title Production of congopain, the major cysteine protease of Trypanosoma (Nannomonas) congolense, in Pichia pastoris reveals unexpected dimerization at physiological Ph
title_full Production of congopain, the major cysteine protease of Trypanosoma (Nannomonas) congolense, in Pichia pastoris reveals unexpected dimerization at physiological Ph
title_fullStr Production of congopain, the major cysteine protease of Trypanosoma (Nannomonas) congolense, in Pichia pastoris reveals unexpected dimerization at physiological Ph
title_full_unstemmed Production of congopain, the major cysteine protease of Trypanosoma (Nannomonas) congolense, in Pichia pastoris reveals unexpected dimerization at physiological Ph
title_short Production of congopain, the major cysteine protease of Trypanosoma (Nannomonas) congolense, in Pichia pastoris reveals unexpected dimerization at physiological Ph
title_sort production of congopain the major cysteine protease of trypanosoma nannomonas congolense in pichia pastoris reveals unexpected dimerization at physiological ph
topic trypanosoma congolense
cysteine protease
trypanosomiasis
animal diseases
livestock
biotechnology
url https://hdl.handle.net/10568/2416
work_keys_str_mv AT boulangeaf productionofcongopainthemajorcysteineproteaseoftrypanosomanannomonascongolenseinpichiapastorisrevealsunexpecteddimerizationatphysiologicalph
AT khamadisa productionofcongopainthemajorcysteineproteaseoftrypanosomanannomonascongolenseinpichiapastorisrevealsunexpecteddimerizationatphysiologicalph
AT pillayd productionofcongopainthemajorcysteineproteaseoftrypanosomanannomonascongolenseinpichiapastorisrevealsunexpecteddimerizationatphysiologicalph
AT coetzertht productionofcongopainthemajorcysteineproteaseoftrypanosomanannomonascongolenseinpichiapastorisrevealsunexpecteddimerizationatphysiologicalph
AT authieedith productionofcongopainthemajorcysteineproteaseoftrypanosomanannomonascongolenseinpichiapastorisrevealsunexpecteddimerizationatphysiologicalph