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Spiwoková P, Horn M, Fanfrlík J, Jílková A, Fajtová P, Leontovyč A, Houštecká R, Bieliková L, Brynda J, Chanová M, Mertlíková-Kaiserová H, Caro-Diaz EJE, Almaliti J, El-Sakkary N, Gerwick WH, Caffrey CR, Mareš M. Nature-Inspired Gallinamides Are Potent Antischistosomal Agents: Inhibition of the Cathepsin B1 Protease Target and Binding Mode Analysis. ACS Infect Dis 2024; 10:1935-1948. [PMID: 38757505 PMCID: PMC11184554 DOI: 10.1021/acsinfecdis.3c00589] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2023] [Revised: 05/09/2024] [Accepted: 05/09/2024] [Indexed: 05/18/2024]
Abstract
Schistosomiasis, caused by a parasitic blood fluke of the genus Schistosoma, is a global health problem for which new chemotherapeutic options are needed. We explored the scaffold of gallinamide A, a natural peptidic metabolite of marine cyanobacteria that has previously been shown to inhibit cathepsin L-type proteases. We screened a library of 19 synthetic gallinamide A analogs and identified nanomolar inhibitors of the cathepsin B-type protease SmCB1, which is a drug target for the treatment of schistosomiasis mansoni. Against cultured S. mansoni schistosomula and adult worms, many of the gallinamides generated a range of deleterious phenotypic responses. Imaging with a fluorescent-activity-based probe derived from gallinamide A demonstrated that SmCB1 is the primary target for gallinamides in the parasite. Furthermore, we solved the high-resolution crystal structures of SmCB1 in complex with gallinamide A and its two analogs and describe the acrylamide covalent warhead and binding mode in the active site. Quantum chemical calculations evaluated the contribution of individual positions in the peptidomimetic scaffold to the inhibition of the target and demonstrated the importance of the P1' and P2 positions. Our study introduces gallinamides as a powerful chemotype that can be exploited for the development of novel antischistosomal chemotherapeutics.
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Affiliation(s)
- Petra Spiwoková
- Institute
of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Flemingovo n. 2, Prague 6 16610, Czech Republic
- Department
of Biochemistry and Microbiology, University
of Chemistry and Technology, Technická 5, Prague 6 16628, Czech Republic
| | - Martin Horn
- Institute
of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Flemingovo n. 2, Prague 6 16610, Czech Republic
| | - Jindřich Fanfrlík
- Institute
of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Flemingovo n. 2, Prague 6 16610, Czech Republic
| | - Adéla Jílková
- Institute
of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Flemingovo n. 2, Prague 6 16610, Czech Republic
| | - Pavla Fajtová
- Institute
of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Flemingovo n. 2, Prague 6 16610, Czech Republic
- Center
for Discovery and Innovation in Parasitic Diseases, Skaggs School
of Pharmacy and Pharmaceutical Sciences, University of California, La Jolla, San Diego, California 92093, United States
| | - Adrian Leontovyč
- Institute
of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Flemingovo n. 2, Prague 6 16610, Czech Republic
| | - Radka Houštecká
- Institute
of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Flemingovo n. 2, Prague 6 16610, Czech Republic
- First
Faculty of Medicine, Charles University, Kateřinská 32, Praha 2 12108, Czech Republic
| | - Lucia Bieliková
- Institute
of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Flemingovo n. 2, Prague 6 16610, Czech Republic
- First
Faculty of Medicine, Charles University, Kateřinská 32, Praha 2 12108, Czech Republic
| | - Jiří Brynda
- Institute
of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Flemingovo n. 2, Prague 6 16610, Czech Republic
| | - Marta Chanová
- Institute
of Immunology and Microbiology, First Faculty of Medicine, Charles University and General University Hospital
in Prague, Studničkova
2028/7, Prague 2 12800, Czech Republic
| | - Helena Mertlíková-Kaiserová
- Institute
of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Flemingovo n. 2, Prague 6 16610, Czech Republic
| | - Eduardo J. E. Caro-Diaz
- Scripps Institution
of Oceanography, University of California, La Jolla, San Diego, California 92093, United States
| | - Jehad Almaliti
- Center
for Discovery and Innovation in Parasitic Diseases, Skaggs School
of Pharmacy and Pharmaceutical Sciences, University of California, La Jolla, San Diego, California 92093, United States
- Scripps Institution
of Oceanography, University of California, La Jolla, San Diego, California 92093, United States
| | - Nelly El-Sakkary
- Center
for Discovery and Innovation in Parasitic Diseases, Skaggs School
of Pharmacy and Pharmaceutical Sciences, University of California, La Jolla, San Diego, California 92093, United States
| | - William H. Gerwick
- Center
for Discovery and Innovation in Parasitic Diseases, Skaggs School
of Pharmacy and Pharmaceutical Sciences, University of California, La Jolla, San Diego, California 92093, United States
- Scripps Institution
of Oceanography, University of California, La Jolla, San Diego, California 92093, United States
| | - Conor R. Caffrey
- Center
for Discovery and Innovation in Parasitic Diseases, Skaggs School
of Pharmacy and Pharmaceutical Sciences, University of California, La Jolla, San Diego, California 92093, United States
| | - Michael Mareš
- Institute
of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Flemingovo n. 2, Prague 6 16610, Czech Republic
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Yang N, Matthew MA, Yao C. Roles of Cysteine Proteases in Biology and Pathogenesis of Parasites. Microorganisms 2023; 11:1397. [PMID: 37374899 DOI: 10.3390/microorganisms11061397] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Revised: 05/18/2023] [Accepted: 05/23/2023] [Indexed: 06/29/2023] Open
Abstract
Cysteine proteases, also known as thiol proteases, are a class of nucleophilic proteolytic enzymes containing cysteine residues in the enzymatic domain. These proteases generally play a pivotal role in many biological reactions, such as catabolic functions and protein processing, in all living organisms. They specifically take part in many important biological processes, especially in the absorption of nutrients, invasion, virulence, and immune evasion of parasitic organisms from unicellular protozoa to multicellular helminths. They can also be used as parasite diagnostic antigens and targets for gene modification and chemotherapy, as well as vaccine candidates, due to their species and even life-cycle stage specificity. This article highlights current knowledge on parasitic cysteine protease types, biological functions, and their applications in immunodiagnosis and chemotherapy.
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Affiliation(s)
- Nawu Yang
- Department of Biomedical Sciences and One Health Center for Zoonoses and Tropical Veterinary Medicine, Ross University School of Veterinary Medicine, Basseterre P.O. Box 334, Saint Kitts and Nevis
| | - Maurice A Matthew
- Department of Biomedical Sciences and One Health Center for Zoonoses and Tropical Veterinary Medicine, Ross University School of Veterinary Medicine, Basseterre P.O. Box 334, Saint Kitts and Nevis
| | - Chaoqun Yao
- Department of Biomedical Sciences and One Health Center for Zoonoses and Tropical Veterinary Medicine, Ross University School of Veterinary Medicine, Basseterre P.O. Box 334, Saint Kitts and Nevis
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Study on activation mechanism and cleavage sites of recombinant butelase-1 zymogen derived from Clitoria ternatea. Biochimie 2022; 199:12-22. [DOI: 10.1016/j.biochi.2022.04.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Revised: 04/04/2022] [Accepted: 04/04/2022] [Indexed: 11/15/2022]
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Jiang S, Xiong Y, Zhang W, Zhu J, Cheng D, Gong Y, Wu Y, Qiao H, Fu H. A Novel Legumain-Like Protease in Macrobrachium nipponense: Identification, Characterization, and Function Analysis in Ovary Maturation. Front Endocrinol (Lausanne) 2022; 13:858726. [PMID: 35399931 PMCID: PMC8987206 DOI: 10.3389/fendo.2022.858726] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Accepted: 02/28/2022] [Indexed: 11/16/2022] Open
Abstract
Legumain, also called aspartic endopeptidase (AEP), is a member of the cysteine protease family and is involved in various physiological processes. In this study, we analyzed the characteristics of a novel legumain-like (named Mn-Lel) in the female oriental river prawn, Macrobrachium nipponense, which is involved in ovary maturation. The Mn-Lel is 1,454 bp in length, including a 1,290-bp open reading frame that encodes 430 amino acids. qPCR analysis indicated that Mn-Lel is specifically highly expressed in the hepatopancreas and ovaries of female prawns. It is rarely expressed in embryogenesis, weakly expressed in early larval development stages, and then significantly increased after metamorphosis, which indicated that Mn-Lel is not a maternal gene and mainly plays a role in adults. During the different ovarian stages, Mn-Lel expression in the hepatopancreas had no obvious rules, while its expression in the ovaries had a significant peak in stage III. In situ hybridization studies revealed that Mn-Lel is localized in the oocyte of the ovary. Changes in the gonadosomatic index confirmed the inhibitory effects of Mn-Lel dsRNA on ovary maturation. These results suggest that Mn-Lel has a key role in promoting ovary maturation.
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Affiliation(s)
- Sufei Jiang
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, China
| | - Yiwei Xiong
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, China
| | - Wenyi Zhang
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, China
| | - Junpeng Zhu
- Wuxi Fisheries College, Nanjing Agricultural University, Wuxi, China
| | - Dan Cheng
- Wuxi Fisheries College, Nanjing Agricultural University, Wuxi, China
| | - Yongsheng Gong
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, China
| | - Yan Wu
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, China
| | - Hui Qiao
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, China
- Wuxi Fisheries College, Nanjing Agricultural University, Wuxi, China
- *Correspondence: Hongtuo Fu, ; Hui Qiao,
| | - Hongtuo Fu
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, China
- Wuxi Fisheries College, Nanjing Agricultural University, Wuxi, China
- *Correspondence: Hongtuo Fu, ; Hui Qiao,
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Corrigan TS, Lotti Diaz LM, Border SE, Ratigan SC, Kasper KQ, Sojka D, Fajtova P, Caffrey CR, Salvesen GS, McElroy CA, Hadad CM, Doğan Ekici Ö. Design, synthesis, and in vitro evaluation of aza-peptide aldehydes and ketones as novel and selective protease inhibitors. J Enzyme Inhib Med Chem 2021; 35:1387-1402. [PMID: 32633155 PMCID: PMC7470110 DOI: 10.1080/14756366.2020.1781107] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Aza-peptide aldehydes and ketones are a new class of reversible protease inhibitors that are specific for the proteasome and clan CD cysteine proteases. We designed and synthesised aza-Leu derivatives that were specific for the chymotrypsin-like active site of the proteasome, aza-Asp derivatives that were effective inhibitors of caspases-3 and -6, and aza-Asn derivatives that inhibited S. mansoni and I. ricinus legumains. The crystal structure of caspase-3 in complex with our caspase-specific aza-peptide methyl ketone inhibitor with an aza-Asp residue at P1 revealed a covalent linkage between the inhibitor carbonyl carbon and the active site cysteinyl sulphur. Aza-peptide aldehydes and ketones showed no cross-reactivity towards cathepsin B or chymotrypsin. The initial in vitro selectivity of these inhibitors makes them suitable candidates for further development into therapeutic agents to potentially treat multiple myeloma, neurodegenerative diseases, and parasitic infections.
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Affiliation(s)
- Thomas S Corrigan
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH, USA
| | - Leilani M Lotti Diaz
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH, USA
| | - Sarah E Border
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH, USA
| | - Steven C Ratigan
- Division of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, The Ohio State University, Columbus, OH, USA
| | - Kayla Q Kasper
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH, USA
| | - Daniel Sojka
- Institute of Parasitology, Biology Centre of the Czech Academy of Sciences, Ceske Budejovice, Czech Republic
| | - Pavla Fajtova
- Center for Discovery and Innovation in Parasitic Diseases, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, CA, USA
| | - Conor R Caffrey
- Center for Discovery and Innovation in Parasitic Diseases, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, CA, USA
| | - Guy S Salvesen
- Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA, USA
| | - Craig A McElroy
- Division of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, The Ohio State University, Columbus, OH, USA
| | - Christopher M Hadad
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH, USA
| | - Özlem Doğan Ekici
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH, USA.,Department of Chemistry and Biochemistry, The Ohio State University at Newark, Newark, OH, USA
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6
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Chen HC, Rui W, You SY, Liu XW, Huang J, Chen HY. Evaluation of the anti-cervical cancer effect of a prodrug :CBZ-AAN-DOX with hypoxic cell culture and tumor-bearing zebrafish models. Exp Cell Res 2020; 391:111980. [PMID: 32229193 DOI: 10.1016/j.yexcr.2020.111980] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Revised: 02/20/2020] [Accepted: 03/26/2020] [Indexed: 10/24/2022]
Abstract
BACKGROUND Prodrugs are medications or compounds that, after administration, can be converted into pharmacologically active drugs through metabolism. Unlike conventional drugs, prodrugs have reduced adverse or unintended effects, which could become critical limitations in treatments such as chemotherapy. Previously through computer-aided drug design and chemical synthesis, we have obtained and examined a prodrug N-benzyloxycarbonyl-Ala-Asn-Doxorubicin (CBZ-AAN-DOX). CBZ-AAN-DOX is essentially Doxorubicin that is chemically-modified with tripeptides to target Legumain, a highly expressed protein in cancer cells and is involved in tumor metastasis and tumor microvessel formation. The difficulty to test the safety and efficacy of the prodrug (including the pharmacodynamic parameters of CBZ-AAN-DOX on metastasis and invasion of tumors, as well as cardiac and vascular toxicity) primarily comes from the lack of appropriate experimental models. METHODS Human cervical cancer cell lines CaSki under hypoxic conditions were used to evaluate the cell viability by CCK-8 assay after the prodrug treatment. Western blotting method was performed for Legumain protein determination in the cell culture. Wound healing and transwell invasion assays were performed to determine the effects of the prodrug on tumor metastasis and invasion, respectively. Zebrafish models were constructed for toxicity and angiogenesis visual analysis after in vivo treatment with the prodrug. RESULTS The CCK-8 results showed that CBZ-AAN-DOX exhibits an IC50 of 28.7 μM in 48 h on CaSki cells that had a lower cell inhibition rate than DOX 80.3 μM for 24 h. Legumain expression was significantly increased in a time-dependent manner in 48 h under hypoxia conditions. The results also showed that 13.9 μM of the prodrug significantly inhibited the migration and invasion of cells and the effects were significantly stronger than that of 41.8 μM of DOX under hypoxia conditions after 48 h. The effects of 160 μM of the prodrug on the survival rate of zebrafish after 72 h and heart-toxicity showed no obvious abnormalities. Cell metastasis and angiogenesis were also inhibited in tumor-bearing zebrafish model. CONCLUSION The findings in this study demonstrated that CBZ-AAN-DOX is a promising chemotherapy candidate with low toxicity and high efficiency for cervical cancer. Remarkably, the hypoxic culture model together with the zebrafish model serve as a good system for the evaluation of the toxicity, targeting and impact of the prodrug on tumor invasion and metastasis.
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Affiliation(s)
- Hong-Ce Chen
- Department of Pathogenic Biology and Immunology, School of Life Sciences and Biopharmaceuticals, Guangdong Pharmaceutical University, Guangzhou, 510632, Guangdong Province, PR China
| | - Wen Rui
- Centre for Novel Drug Research and Development, Guangdong Pharmaceutical University, Guangzhou, 510006, Guangdong Province, PR China; Guangdong Engineering & Technology Research Center of Topical Precise Drug Delivery System, Guangdong Pharmaceutical University, Guangzhou, 510006, Guangdong Province, PR China; Key Laboratory of Digital Quality Evaluation of Chinese Materia Medica of State Administration of TCM, Guangzhou, 510006, Guangdong Province, PR China
| | - Si-Yuan You
- Department of Pathogenic Biology and Immunology, School of Life Sciences and Biopharmaceuticals, Guangdong Pharmaceutical University, Guangzhou, 510632, Guangdong Province, PR China
| | - Xia-Wan Liu
- Department of Pathogenic Biology and Immunology, School of Life Sciences and Biopharmaceuticals, Guangdong Pharmaceutical University, Guangzhou, 510632, Guangdong Province, PR China
| | - Jun Huang
- Key Laboratory of Immunology, Sino-French Hoffmann Institute, School of Basic Medical Sciences; Guangdong Provincial Key Laboratory of Allergy & Clinical Immunology, The Second Affiliated Hospital, Guangzhou Medical University, Guangzhou, 511436, Guangdong Province, PR China
| | - Hong-Yuan Chen
- Department of Pathogenic Biology and Immunology, School of Life Sciences and Biopharmaceuticals, Guangdong Pharmaceutical University, Guangzhou, 510632, Guangdong Province, PR China; Guangdong Engineering & Technology Research Center of Topical Precise Drug Delivery System, Guangdong Pharmaceutical University, Guangzhou, 510006, Guangdong Province, PR China; Key Laboratory of Digital Quality Evaluation of Chinese Materia Medica of State Administration of TCM, Guangzhou, 510006, Guangdong Province, PR China.
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7
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Dvořáková H, Leontovyč R, Macháček T, O'Donoghue AJ, Šedo O, Zdráhal Z, Craik CS, Caffrey CR, Horák P, Mikeš L. Isoforms of Cathepsin B1 in Neurotropic Schistosomula of Trichobilharzia regenti Differ in Substrate Preferences and a Highly Expressed Catalytically Inactive Paralog Binds Cystatin. Front Cell Infect Microbiol 2020; 10:66. [PMID: 32175287 PMCID: PMC7054455 DOI: 10.3389/fcimb.2020.00066] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Accepted: 02/07/2020] [Indexed: 11/13/2022] Open
Abstract
Schistosomula (the post-infective stages) of the neurotropic schistosome Trichobilharzia regenti possess multiple isoforms of cathepsin B1 peptidase (TrCB1.1-TrCB1.6) with involvement in nutrient digestion. The comparison of substrate preferences of TrCB1.1 and TrCB1.4 showed that TrCB1.4 had a very narrow substrate specificity and after processing it was less effective toward protein substrates when compared to TrCB1.1. Self-processing of both isoforms could be facilitated by sulfated polysaccharides due to a specific binding motif in the pro-sequence. Trans-activation by heterologous enzymes was also successfully employed. Expression profiling revealed a high level of transcription of genes encoding the enzymatically inactive paralogs TrCB1.5 and TrCB1.6. The transcription level of TrCB1.6 was comparable with that of TrCB1.1 and TrCB1.2, the most abundant active isoforms. Recombinant TrCB1.6wt, a wild type paralog with a Cys29-to-Gly substitution in the active site that renders the enzyme inactive, was processed by the active TrCB1 forms and by an asparaginyl endopeptidase. Although TrCB1.6wt lacked hydrolytic activity, endopeptidase, but not dipeptidase, activity could be restored by mutating Gly29 to Cys29. The lack of exopeptidase activity may be due to other mutations, such as His110-to-Asn in the occluding loop and Asp224-to-Gly in the main body of the mature TrCB1.6, which do not occur in the active isoforms TrCB1.1 and TrCB1.4 with exopeptidase activity. The catalytically active enzymes and the inactive TrCB1.6 paralog formed complexes with chicken cystatin, thus supporting experimentally the hypothesis that inactive paralogs could potentially regulate the activity of the active forms or protect them from being inhibited by host inhibitors. The effect on cell viability and nitric oxide production by selected immune cells observed for TrCB1.1 was not confirmed for TrCB1.6. We show here that the active isoforms of TrCB1 have different affinities for peptide substrates thereby facilitating diversity in protein-derived nutrition for the parasite. The inactive paralogs are unexpectedly highly expressed and one of them retains the ability to bind cystatins, likely due to specific mutations in the occluding loop and the enzyme body. This suggests a role in sequestration of inhibitors and protection of active cysteine peptidases.
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Affiliation(s)
- Hana Dvořáková
- Department of Parasitology, Faculty of Science, Charles University, Prague, Czechia
| | - Roman Leontovyč
- Department of Parasitology, Faculty of Science, Charles University, Prague, Czechia
| | - Tomáš Macháček
- Department of Parasitology, Faculty of Science, Charles University, Prague, Czechia
| | - Anthony J. O'Donoghue
- Department of Pharmaceutical Chemistry, School of Pharmacy, University of California, San Francisco, San Francisco, CA, United States
| | - Ondřej Šedo
- Central European Institute of Technology, Masaryk University, Brno, Czechia
| | - Zbyněk Zdráhal
- Central European Institute of Technology, Masaryk University, Brno, Czechia
| | - Charles S. Craik
- Department of Pharmaceutical Chemistry, School of Pharmacy, University of California, San Francisco, San Francisco, CA, United States
| | - Conor R. Caffrey
- Center for Discovery and Innovation in Parasitic Diseases, Department of Pathology, University of California, San Francisco, San Francisco, CA, United States
| | - Petr Horák
- Department of Parasitology, Faculty of Science, Charles University, Prague, Czechia
| | - Libor Mikeš
- Department of Parasitology, Faculty of Science, Charles University, Prague, Czechia
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Abstract
Schistosomiasis caused by parasitic blood flukes of the genus Schistosoma is a global health problem with over 200 million people infected. Schistosoma mansoni cathepsin B1 (SmCB1) is a gut-associated protease critical for digestion of host blood proteins as a source of nutrients. SmCB1 is a validated drug target, and inhibitors of SmCB1 represent promising anti-schistosomals. A comprehensive structural and functional characterization of SmCB1 provides a starting point for the rational design of selective and potent SmCB1 inhibitors. Here, we report optimized protocols for (1) the production of recombinant SmCB1 in the Pichia pastoris expression system and its purification, (2) the measurement of SmCB1 activity and inhibition in a kinetic fluorescence assay, and (3) the preparation and crystallization of SmCB1 in complex with a model vinyl sulfone inhibitor, and the determination of its crystal structure.
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9
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Lorenzo MA, Gauna AN, Herrera J, Bermúdez H, Losada S, Noya O, Serrano ML. In silico modeling and structural analysis of asparaginyl endopeptidase of schistosoma mansoni (Sm32): Immunological and drug target implications. Comput Biol Chem 2019; 78:18-27. [DOI: 10.1016/j.compbiolchem.2018.11.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2018] [Revised: 11/14/2018] [Accepted: 11/16/2018] [Indexed: 11/17/2022]
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James AM, Haywood J, Mylne JS. Macrocyclization by asparaginyl endopeptidases. THE NEW PHYTOLOGIST 2018; 218:923-928. [PMID: 28322452 DOI: 10.1111/nph.14511] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2016] [Accepted: 01/24/2017] [Indexed: 05/18/2023]
Abstract
Contents Summary 923 I. Introduction 923 II. Plant AEPs with macrocyclizing ability 924 III. Mechanism of macrocyclization by AEPs 925 IV. Conclusions 927 Acknowledgements 927 References 927 SUMMARY: Plant asparaginyl endopeptidases (AEPs) are important for the post-translational processing of seed storage proteins via cleavage of precursor proteins. Some AEPs also function as peptide bond-makers during the biosynthesis of several unrelated classes of cyclic peptides, namely the kalata-type cyclic peptides, PawS-Derived Peptides and cyclic knottins. These three families of gene-encoded peptides have different evolutionary origins, but all have recruited AEPs for their maturation. In the last few years, the field has advanced rapidly, with the biochemical characterization of three plant AEPs capable of peptide macrocyclization, and insights have been gained from the first AEP crystal structures, albeit mammalian ones. Although the biochemical studies have improved our understanding of the mechanism of action, the focus now is to understand what changes in AEP sequence and structure enable some plant AEPs to perform macrocyclization reactions.
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Affiliation(s)
- Amy M James
- School of Molecular Sciences & The ARC Centre of Excellence in Plant Energy Biology, The University of Western Australia, 35 Stirling Highway, Crawley, Perth, 6009, Australia
| | - Joel Haywood
- School of Molecular Sciences & The ARC Centre of Excellence in Plant Energy Biology, The University of Western Australia, 35 Stirling Highway, Crawley, Perth, 6009, Australia
| | - Joshua S Mylne
- School of Molecular Sciences & The ARC Centre of Excellence in Plant Energy Biology, The University of Western Australia, 35 Stirling Highway, Crawley, Perth, 6009, Australia
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11
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Hartmann D, Šíma R, Konvičková J, Perner J, Kopáček P, Sojka D. Multiple legumain isoenzymes in ticks. Int J Parasitol 2017; 48:167-178. [PMID: 29113783 DOI: 10.1016/j.ijpara.2017.08.011] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2017] [Revised: 08/16/2017] [Accepted: 08/22/2017] [Indexed: 10/18/2022]
Abstract
By searching nucleotide databases for the North American Lyme disease vector, Ixodes scapularis, we have complemented the previously characterized European Ixodes ricinus legumain IrAE1 with a full set of nine analogous genes (isae1-9). Six of these were PCR confirmed as genes present in all tick genomes tested. The absolute mRNA copy number examined by quantitative (q)PCR enabled expression profiling and an absolute comparison of mRNA levels for individual I. scapularis (Is)AEs in tick tissues. Four IsAEs (1, 2, 4, 9) were expressed solely in the gut and thus are proposed to be involved in host blood digestion. Expression qPCR profiling over developmental stages confirmed IsAE1, the direct analogue of previously characterized I. ricinus IrAE1, as the principle legumain transcript in partially engorged females, and demonstrated its strong regulation by on-host feeding in larvae, nymphs and females. In contrast, IsAE2 was the predominant gut legumain in unfed nymphs, unfed females and males. In-silico, IsAE1 and IsAE2 protein three-dimensional structural models displayed minimal differences in overall proenzyme structures, even in comparison with recently resolved crystal structures of mammalian prolegumain. Three functional studies were performed in I. ricinus with IsAE1/IsAE2 analogues: double IrAE1/IrAE2 RNA interference silencing, feeding of ticks on IrAE1+IrAE2 immunized hosts and in vitro membrane tick feeding on blood containing a legumain-specific inhibitor. The latter experiment led to reduced weights of fully engorged ticks and limited oviposition, and indicated the potential of legumain inhibitors for novel anti-tick interventions.
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Affiliation(s)
- David Hartmann
- Institute of Parasitology, Biology Centre of the Czech Academy of Sciences, České Budějovice CZ-370 05, Czech Republic; Faculty of Sciences, University of South Bohemia, České Budějovice CZ-370 05, Czech Republic
| | - Radek Šíma
- Institute of Parasitology, Biology Centre of the Czech Academy of Sciences, České Budějovice CZ-370 05, Czech Republic
| | - Jitka Konvičková
- Institute of Parasitology, Biology Centre of the Czech Academy of Sciences, České Budějovice CZ-370 05, Czech Republic; Faculty of Sciences, University of South Bohemia, České Budějovice CZ-370 05, Czech Republic
| | - Jan Perner
- Institute of Parasitology, Biology Centre of the Czech Academy of Sciences, České Budějovice CZ-370 05, Czech Republic
| | - Petr Kopáček
- Institute of Parasitology, Biology Centre of the Czech Academy of Sciences, České Budějovice CZ-370 05, Czech Republic
| | - Daniel Sojka
- Institute of Parasitology, Biology Centre of the Czech Academy of Sciences, České Budějovice CZ-370 05, Czech Republic.
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Biological function of Dictyocaulus viviparus asparaginyl peptidase legumain-1 and its suitability as a vaccine target. Parasitology 2017; 145:378-392. [PMID: 28942744 DOI: 10.1017/s0031182017001573] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The present study characterized the biological function of the asparaginyl peptidase legumain-1 (LEG-1) of the bovine lungworm Dictyocaulus viviparus and its suitability as a recombinant vaccine against dictyocaulosis. Quantitative real-time PCR and immunoblot analysis revealed LEG-1 to be almost exclusively transcribed and expressed in parasitic lungworm stages. Immunohistochemistry localized the enzyme in the parasite's gut, which was confirmed by immunoblots detecting LEG-1 in the gut as well as male testes. LEG-1 was recombinantly (rLEG-1) expressed in the yeast Pichia pastoris and subsequently analysed in activity assays for its enzyme functions and substrate specificity. For sufficient functionality, rLEG-1 needed trans-activation through D. viviparus cathepsin L-2, indicating a novel mechanism of legumain activation. After trans-activation, rLEG-1 worked best at pH 5·5 and 35-39 °C and cleaved a legumain-specific artificial substrate as well as the natural substrates bovine collagen types I and II. In a clinical vaccination trial, rLEG-1 did not protect against challenge infection. Results of in vitro characterization, transcription pattern and localization enhance the presumption that LEG-1 participates in digestion processes of D. viviparus. Since rLEG-1 needs trans-activation through a cathepsin, it is probably involved in an enzyme cascade and therefore remains interesting as a candidate in a multi-component vaccine.
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Goupil LS, Ivry SL, Hsieh I, Suzuki BM, Craik CS, O’Donoghue AJ, McKerrow JH. Cysteine and Aspartyl Proteases Contribute to Protein Digestion in the Gut of Freshwater Planaria. PLoS Negl Trop Dis 2016; 10:e0004893. [PMID: 27501047 PMCID: PMC4976874 DOI: 10.1371/journal.pntd.0004893] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2016] [Accepted: 07/11/2016] [Indexed: 01/06/2023] Open
Abstract
Proteases perform numerous vital functions in flatworms, many of which are likely to be conserved throughout the phylum Platyhelminthes. Within this phylum are several parasitic worms that are often poorly characterized due to their complex life-cycles and lack of responsiveness to genetic manipulation. The flatworm Schmidtea mediterranea, or planaria, is an ideal model organism to study the complex role of protein digestion due to its simple life cycle and amenability to techniques like RNA interference (RNAi). In this study, we were interested in deconvoluting the digestive protease system that exists in the planarian gut. To do this, we developed an alcohol-induced regurgitation technique to enrich for the gut enzymes in S. mediterranea. Using a panel of fluorescent substrates, we show that this treatment produces a sharp increase in proteolytic activity. These enzymes have broad yet diverse substrate specificity profiles. Proteomic analysis of the gut contents revealed the presence of cysteine and metallo-proteases. However, treatment with class-specific inhibitors showed that aspartyl and cysteine proteases are responsible for the majority of protein digestion. Specific RNAi knockdown of the cathepsin B-like cysteine protease (SmedCB) reduced protein degradation in vivo. Immunohistochemistry and whole-mount in situ hybridization (WISH) confirmed that the full-length and active forms of SmedCB are found in secretory cells surrounding the planaria intestinal lumen. Finally, we show that the knockdown of SmedCB reduces the speed of tissue regeneration. Defining the roles of proteases in planaria can provide insight to functions of conserved proteases in parasitic flatworms, potentially uncovering drug targets in parasites.
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Affiliation(s)
- Louise S. Goupil
- Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, California, United States of America
| | - Sam L. Ivry
- Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, California, United States of America
| | - Ivy Hsieh
- Department of Pathology, University of California, San Francisco, San Francisco, California, United States of America
| | - Brian M. Suzuki
- Skaggs School of Pharmacy and Pharmaceutical Chemistry, University of California, San Diego, La Jolla, California, United States of America
| | - Charles S. Craik
- Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, California, United States of America
| | - Anthony J. O’Donoghue
- Skaggs School of Pharmacy and Pharmaceutical Chemistry, University of California, San Diego, La Jolla, California, United States of America
| | - James H. McKerrow
- Skaggs School of Pharmacy and Pharmaceutical Chemistry, University of California, San Diego, La Jolla, California, United States of America
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Next Generation Sequencing Identifies Five Major Classes of Potentially Therapeutic Enzymes Secreted by Lucilia sericata Medical Maggots. BIOMED RESEARCH INTERNATIONAL 2016; 2016:8285428. [PMID: 27119084 PMCID: PMC4826915 DOI: 10.1155/2016/8285428] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/29/2016] [Accepted: 03/07/2016] [Indexed: 01/01/2023]
Abstract
Lucilia sericata larvae are used as an alternative treatment for recalcitrant and chronic wounds. Their excretions/secretions contain molecules that facilitate tissue debridement, disinfect, or accelerate wound healing and have therefore been recognized as a potential source of novel therapeutic compounds. Among the substances present in excretions/secretions various peptidase activities promoting the wound healing processes have been detected but the peptidases responsible for these activities remain mostly unidentified. To explore these enzymes we applied next generation sequencing to analyze the transcriptomes of different maggot tissues (salivary glands, gut, and crop) associated with the production of excretions/secretions and/or with digestion as well as the rest of the larval body. As a result we obtained more than 123.8 million paired-end reads, which were assembled de novo using Trinity and Oases assemblers, yielding 41,421 contigs with an N50 contig length of 2.22 kb and a total length of 67.79 Mb. BLASTp analysis against the MEROPS database identified 1729 contigs in 577 clusters encoding five peptidase classes (serine, cysteine, aspartic, threonine, and metallopeptidases), which were assigned to 26 clans, 48 families, and 185 peptidase species. The individual enzymes were differentially expressed among maggot tissues and included peptidase activities related to the therapeutic effects of maggot excretions/secretions.
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Major acid endopeptidases of the blood-feeding monogenean Eudiplozoon nipponicum (Heteronchoinea: Diplozoidae). Parasitology 2016; 143:494-506. [PMID: 26888494 DOI: 10.1017/s0031182015001808] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
In parasitic flatworms, acid endopeptidases are involved in crucial processes, including digestion, invasion, interactions with the host immune system, etc. In haematophagous monogeneans, however, no solid information has been available about the occurrence of these enzymes. Here we aimed to identify major cysteine and aspartic endopeptidase activities in Eudiplozoon nipponicum, an invasive haematophagous parasite of common carp. Employing biochemical, proteomic and molecular tools, we found that cysteine peptidase activities prevailed in soluble protein extracts and excretory/secretory products (ESP) of E. nipponicum; the major part was cathepsin L-like in nature supplemented with cathepsin B-like activity. Significant activity of the aspartic cathepsin D also occurred in soluble protein extracts. The degradation of haemoglobin in the presence of ESP and worm protein extracts was completely inhibited by a combination of cysteine and aspartic peptidase inhibitors, and diminished by particular cathepsin L, B and D inhibitors. Mass spectrometry revealed several tryptic peptides in ESP matching to two translated sequences of cathepsin L genes, which were amplified from cDNA of E. nipponicum and bioinformatically annotated. The dominance of cysteine peptidases of cathepsin L type in E. nipponicum resembles the situation in, e.g. fasciolid trematodes.
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16
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Structure and function of legumain in health and disease. Biochimie 2015; 122:126-50. [PMID: 26403494 DOI: 10.1016/j.biochi.2015.09.022] [Citation(s) in RCA: 194] [Impact Index Per Article: 21.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2015] [Accepted: 09/18/2015] [Indexed: 12/27/2022]
Abstract
The last years have seen a steady increase in our understanding of legumain biology that is driven from two largely uncoupled research arenas, the mammalian and the plant legumain field. Research on legumain, which is also referred to as asparaginyl endopeptidase (AEP) or vacuolar processing enzyme (VPE), is slivered, however. Here we summarise recent important findings and put them into a common perspective. Legumain is usually associated with its cysteine endopeptidase activity in lysosomes where it contributes to antigen processing for class II MHC presentation. However, newly recognized functions disperse previously assumed boundaries with respect to their cellular compartmentalisation and enzymatic activities. Legumain is also found extracellularly and even translocates to the cytosol and the nucleus, with seemingly incompatible pH and redox potential. These different milieus translate into changes of legumain's molecular properties, including its (auto-)activation, conformational stability and enzymatic functions. Contrasting its endopeptidase activity, legumain can develop a carboxypeptidase activity which remains stable at neutral pH. Moreover, legumain features a peptide ligase activity, with intriguing mechanistic peculiarities in plant and human isoforms. In pathological settings, such as cancer or Alzheimer's disease, the proper association of legumain activities with the corresponding cellular compartments is breached. Legumain's increasingly recognized physiological and pathological roles also indicate future research opportunities in this vibrant field.
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Santamaría ME, González-Cabrera J, Martínez M, Grbic V, Castañera P, Díaz L, Ortego F. Digestive proteases in bodies and faeces of the two-spotted spider mite, Tetranychus urticae. JOURNAL OF INSECT PHYSIOLOGY 2015; 78:69-77. [PMID: 25960286 DOI: 10.1016/j.jinsphys.2015.05.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2015] [Revised: 05/06/2015] [Accepted: 05/06/2015] [Indexed: 05/04/2023]
Abstract
Digestive proteases of the phytophagous mite Tetranychus urticae have been characterised by comparing their activity in body and faecal extracts. Aspartyl, cathepsin B- and L-like and legumain activities were detected in both mite bodies and faeces, with a specific activity of aspartyl and cathepsin L-like proteases about 5- and 2-fold higher, respectively, in mite faeces than in bodies. In general, all these activities were maintained independently of the host plant where the mites were reared (bean, tomato or maize). Remarkably, this is the first report in a phytophagous mite of legumain-like activity, which was characterised for its ability to hydrolyse the specific substrate Z-VAN-AMC, its activation by DTT and inhibition by IAA but not by E-64. Gel free nanoLC-nanoESI-QTOF MS/MS proteomic analysis of mite faeces resulted in the identification of four cathepsins L and one aspartyl protease (from a total of the 29 cathepsins L, 27 cathepsins B, 19 legumains and two aspartyl protease genes identified the genome of this species). Gene expression analysis reveals that four cathepsins L and the aspartyl protease identified in the mite faeces, but also two cathepsins B and two legumains that were not detected in the faeces, were expressed at high levels in the spider mite feeding stages (larvae, nymphs and adults) relative to embryos. Taken together, these results indicate a digestive role for cysteine and aspartyl proteases in T. urticae. The expression of the cathepsins B and L, legumains and aspartyl protease genes analysed in our study increased in female adults after feeding on Arabidopsis plants over-expressing the HvCPI-6 cystatin, that specifically targets cathepsins B and L, or the CMe trypsin inhibitor that targets serine proteases. This unspecific response suggests that in addition to compensation for inhibitor-targeted enzymes, the increase in the expression of digestive proteases in T. urticae may act as a first barrier against ingested plant defensive proteins.
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Affiliation(s)
- María E Santamaría
- Departamento de Biología Medioambiental, Centro de Investigaciones Biológicas, CSIC, Ramiro de Maeztu, 9, 28040 Madrid, Spain; Centro de Biotecnología y Genómica de Plantas, Universidad Politécnica de Madrid, Campus Montegancedo, Autovía M40 (Km 38), 28223 Pozuelo de Alarcón, Madrid, Spain; Department of Biology WSC 339/341, The University of Western Ontario, 1151 Richmond St, London, ON N6A 5B7, Canada
| | - Joel González-Cabrera
- Departamento de Biología Medioambiental, Centro de Investigaciones Biológicas, CSIC, Ramiro de Maeztu, 9, 28040 Madrid, Spain
| | - Manuel Martínez
- Centro de Biotecnología y Genómica de Plantas, Universidad Politécnica de Madrid, Campus Montegancedo, Autovía M40 (Km 38), 28223 Pozuelo de Alarcón, Madrid, Spain
| | - Vojislava Grbic
- Department of Biology WSC 339/341, The University of Western Ontario, 1151 Richmond St, London, ON N6A 5B7, Canada
| | - Pedro Castañera
- Departamento de Biología Medioambiental, Centro de Investigaciones Biológicas, CSIC, Ramiro de Maeztu, 9, 28040 Madrid, Spain
| | - Lsabel Díaz
- Centro de Biotecnología y Genómica de Plantas, Universidad Politécnica de Madrid, Campus Montegancedo, Autovía M40 (Km 38), 28223 Pozuelo de Alarcón, Madrid, Spain
| | - Félix Ortego
- Departamento de Biología Medioambiental, Centro de Investigaciones Biológicas, CSIC, Ramiro de Maeztu, 9, 28040 Madrid, Spain.
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Kang JM, Lee J, Ju HL, Ju JW, Kim JH, Pak JH, Kim TS, Hong Y, Sohn WM, Na BK. Characterization of a gut-associated asparaginyl endopeptidase of Clonorchis sinensis. Exp Parasitol 2015; 153:81-90. [DOI: 10.1016/j.exppara.2015.03.015] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2014] [Revised: 03/12/2015] [Accepted: 03/20/2015] [Indexed: 12/17/2022]
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19
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Spohner SC, Müller H, Quitmann H, Czermak P. Expression of enzymes for the usage in food and feed industry with Pichia pastoris. J Biotechnol 2015; 202:118-34. [DOI: 10.1016/j.jbiotec.2015.01.027] [Citation(s) in RCA: 66] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2014] [Revised: 12/28/2014] [Accepted: 01/07/2015] [Indexed: 12/29/2022]
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20
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Figueiredo BCP, Ricci ND, de Assis NRG, de Morais SB, Fonseca CT, Oliveira SC. Kicking in the Guts: Schistosoma mansoni Digestive Tract Proteins are Potential Candidates for Vaccine Development. Front Immunol 2015; 6:22. [PMID: 25674091 PMCID: PMC4309203 DOI: 10.3389/fimmu.2015.00022] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2014] [Accepted: 01/09/2015] [Indexed: 12/24/2022] Open
Abstract
Schistosomiasis is a debilitating disease that represents a major health problem in at least 74 tropical and subtropical countries. Current disease control strategies consist mainly of chemotherapy, which cannot prevent recurrent re-infection of people living in endemic area. In the last decades, many researchers made a remarkable effort in the search for an effective vaccine to provide long-term protection. Parasitic platyhelminthes of Schistosoma genus, which cause the disease, live in the blood vessels of definitive hosts where they are bathed in host blood for many years. Among the most promising molecules as vaccine candidates are the proteins present in the host–parasite interface, so numerous tegument antigens have been assessed and the achieved protection never got even close to 100%. Besides the tegument, the digestive tract is the other major site of host–parasite interface. Since parasites feed on blood, they need to swallow a considerable amount of blood for nutrient acquisition. Host blood ingested by schistosomes passes through the esophagus and reaches the gut where many peptidases catalyze the proteolysis of blood cells. Recent studies show the emergence of antigens related to the parasite blood feeding, such as esophageal gland proteins, proteases, and other proteins related to nutrient uptake. Herein, we review what is known about Schistosoma mansoni digestive tract proteins, emphasizing the ones described as potential vaccine candidates.
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Affiliation(s)
- Barbara Castro-Pimentel Figueiredo
- Laboratório de Imunologia de Doenças Infecciosas, Departamento de Bioquímica e Imunologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais , Belo Horizonte , Brazil ; Instituto Nacional de Ciência e Tecnologia em Doenças Tropicais (INCT-DT), Conselho Nacional de Desenvolvimento Científico e Tecnológico, Ministério de Ciência Tecnologia e Inovação, Universidade Federal de Minas Gerais , Belo Horizonte , Brazil
| | - Natasha Delaqua Ricci
- Laboratório de Imunologia de Doenças Infecciosas, Departamento de Bioquímica e Imunologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais , Belo Horizonte , Brazil ; Instituto Nacional de Ciência e Tecnologia em Doenças Tropicais (INCT-DT), Conselho Nacional de Desenvolvimento Científico e Tecnológico, Ministério de Ciência Tecnologia e Inovação, Universidade Federal de Minas Gerais , Belo Horizonte , Brazil
| | - Natan Raimundo Gonçalves de Assis
- Laboratório de Imunologia de Doenças Infecciosas, Departamento de Bioquímica e Imunologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais , Belo Horizonte , Brazil ; Instituto Nacional de Ciência e Tecnologia em Doenças Tropicais (INCT-DT), Conselho Nacional de Desenvolvimento Científico e Tecnológico, Ministério de Ciência Tecnologia e Inovação, Universidade Federal de Minas Gerais , Belo Horizonte , Brazil
| | - Suellen Batistoni de Morais
- Laboratório de Imunologia de Doenças Infecciosas, Departamento de Bioquímica e Imunologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais , Belo Horizonte , Brazil ; Instituto Nacional de Ciência e Tecnologia em Doenças Tropicais (INCT-DT), Conselho Nacional de Desenvolvimento Científico e Tecnológico, Ministério de Ciência Tecnologia e Inovação, Universidade Federal de Minas Gerais , Belo Horizonte , Brazil
| | - Cristina Toscano Fonseca
- Instituto Nacional de Ciência e Tecnologia em Doenças Tropicais (INCT-DT), Conselho Nacional de Desenvolvimento Científico e Tecnológico, Ministério de Ciência Tecnologia e Inovação, Universidade Federal de Minas Gerais , Belo Horizonte , Brazil ; Laboratório de Esquistossomose do Centro de Pesquisas René Rachou, Fundação Oswaldo Cruz , Belo Horizonte , Brazil
| | - Sergio Costa Oliveira
- Laboratório de Imunologia de Doenças Infecciosas, Departamento de Bioquímica e Imunologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais , Belo Horizonte , Brazil ; Instituto Nacional de Ciência e Tecnologia em Doenças Tropicais (INCT-DT), Conselho Nacional de Desenvolvimento Científico e Tecnológico, Ministério de Ciência Tecnologia e Inovação, Universidade Federal de Minas Gerais , Belo Horizonte , Brazil
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Jílková A, Horn M, Řezáčová P, Marešová L, Fajtová P, Brynda J, Vondrášek J, McKerrow JH, Caffrey CR, Mareš M. Activation route of the Schistosoma mansoni cathepsin B1 drug target: structural map with a glycosaminoglycan switch. Structure 2014; 22:1786-1798. [PMID: 25456815 DOI: 10.1016/j.str.2014.09.015] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2014] [Revised: 09/22/2014] [Accepted: 09/23/2014] [Indexed: 01/11/2023]
Abstract
Cathepsin B1 (SmCB1) is a digestive protease of the parasitic blood fluke Schistosoma mansoni and a drug target for the treatment of schistosomiasis, a disease that afflicts over 200 million people. SmCB1 is synthesized as an inactive zymogen in which the N-terminal propeptide blocks the active site. We investigated the activation of the zymogen by which the propeptide is proteolytically removed and its regulation by sulfated polysaccharides (SPs). We determined crystal structures of three molecular forms of SmCB1 along the activation pathway: the zymogen, an activation intermediate with a partially cleaved propeptide, and the mature enzyme. We demonstrate that SPs are essential for the autocatalytic activation of SmCB1, as they interact with a specific heparin-binding domain in the propeptide. An alternative activation route is mediated by an S. mansoni asparaginyl endopeptidase (legumain) which is downregulated by SPs, indicating that SPs act as a molecular switch between both activation mechanisms.
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Affiliation(s)
- Adéla Jílková
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, 16610 Prague, Czech Republic; Department of Biochemistry, Faculty of Science, Charles University in Prague, 12843 Prague, Czech Republic
| | - Martin Horn
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, 16610 Prague, Czech Republic
| | - Pavlína Řezáčová
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, 16610 Prague, Czech Republic; Department of Structural Biology, Institute of Molecular Genetics, Academy of Sciences of the Czech Republic, 14220 Prague, Czech Republic
| | - Lucie Marešová
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, 16610 Prague, Czech Republic
| | - Pavla Fajtová
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, 16610 Prague, Czech Republic
| | - Jiří Brynda
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, 16610 Prague, Czech Republic; Department of Structural Biology, Institute of Molecular Genetics, Academy of Sciences of the Czech Republic, 14220 Prague, Czech Republic
| | - Jiří Vondrášek
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, 16610 Prague, Czech Republic
| | - James H McKerrow
- Department of Pathology, Center for Discovery and Innovation in Parasitic Diseases, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Conor R Caffrey
- Department of Pathology, Center for Discovery and Innovation in Parasitic Diseases, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Michael Mareš
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, 16610 Prague, Czech Republic.
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Santos-Silva LK, Soares-Costa A, Gerald LTS, Meneghin SP, Henrique-Silva F. Recombinant expression and biochemical characterization of sugarcane legumain. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2012; 57:181-92. [PMID: 22721948 DOI: 10.1016/j.plaphy.2012.05.020] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2012] [Accepted: 05/17/2012] [Indexed: 05/01/2023]
Abstract
Plant legumains, also termed vacuolar processing enzymes (VPEs), are cysteine peptidases that play key roles in plant development, senescence, programmed cell death and defense against pathogens. Despite the increasing number of reports on plant cysteine peptidases, including VPEs, the characterization of sugarcane VPEs and their inhibition by endogenous cystatins have not yet been described. This is the first report of the biochemical characterization of a sugarcane cysteine peptidase. In this work, a recombinant sugarcane legumain was expressed in Pichia pastoris and characterized. Kinetic studies of the recombinant CaneLEG revealed that this enzyme has the main characteristics of VPEs, such as self-activation and activity under acidic pH. CaneLEG activity was strongly inhibited when incubated with sugarcane cystatin 3 (CaneCPI-3). Quantitative analysis of CaneLEG and CaneCPI-3 gene expression indicated a tissue-specific expression pattern for both genes throughout sugarcane growth, with the strong accumulation of CaneLEG transcripts throughout the internode development. Furthermore, the CaneLEG and CaneCPI-3 genes exhibited up-regulation in plantlets treated with abscisic acid (ABA). These results suggest that CaneCPI-3 may be a potential endogenous inhibitor of CaneLEG and these genes may be involved in plant stress response mediated by ABA. Also, the expression analysis provides clues for the putative involvement of CaneLEG and CaneCPI-3 in sugarcane development and phytohormone response.
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Affiliation(s)
- Ludier K Santos-Silva
- Department of Genetics and Evolution, Federal University of São Carlos, Rodovia Washington Luís, São Carlos SP, Brazil
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23
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Ni F, Wang Y, Zhang J, Yu L, Fang W, Luo D. Cathepsin B-like and hemoglobin-type cysteine proteases: stage-specific gene expression in Angiostrongy cantonensis. Exp Parasitol 2012; 131:433-41. [PMID: 22668746 DOI: 10.1016/j.exppara.2012.05.014] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2012] [Revised: 05/22/2012] [Accepted: 05/28/2012] [Indexed: 10/28/2022]
Abstract
Three cysteine protease genes, cathepsin B-like enzyme gene 1, 2 (AC-cathB-1, AC-cathB-2) and hemoglobin-type cysteine protease gene (AC-hem) were isolated and described from Angiostrongylus cantonensis adult. The deduced amino acid sequence of Ac-cathB-1 and AC-cathB-2 contain all of the conserved regions of cathepsin B. AC-cathB-2 is similar to a host intrusion-related cysteine protease B from Parelaphostrongylus tenuis, and the AC-hem shares high similarity to legumain from Haemonchus contortus. AC-cathB-1 was expressed significantly higher in L1 as compared with AC-hem, the AC-cathB-2 followed; AC-cathB-2 transcripts in L3 were found increased rapidly and obviously abundant, suggesting that AC-cathB-1 and AC-cathB-2 may play an important role in intermediate and final host invasion, separately. The cysteine protease genes were more or less expressed in adult stage excepted for AC-cathB-2. As the AC-cathB-1 and AC-hem highly expressed in adult worms, suggesting AC-hem may activate AC-cathB-1 which involved in the host invasion and feeding process.
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Affiliation(s)
- Fang Ni
- School of Life Sciences, Xiamen University, Xiamen, Fujian 361005, China
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Jílková A, Řezáčová P, Lepšík M, Horn M, Váchová J, Fanfrlík J, Brynda J, McKerrow JH, Caffrey CR, Mareš M. Structural basis for inhibition of cathepsin B drug target from the human blood fluke, Schistosoma mansoni. J Biol Chem 2011; 286:35770-35781. [PMID: 21832058 PMCID: PMC3195637 DOI: 10.1074/jbc.m111.271304] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2011] [Revised: 07/19/2011] [Indexed: 11/06/2022] Open
Abstract
Schistosomiasis caused by a parasitic blood fluke of the genus Schistosoma afflicts over 200 million people worldwide. Schistosoma mansoni cathepsin B1 (SmCB1) is a gut-associated peptidase that digests host blood proteins as a source of nutrients. It is under investigation as a drug target. To further this goal, we report three crystal structures of SmCB1 complexed with peptidomimetic inhibitors as follows: the epoxide CA074 at 1.3 Å resolution and the vinyl sulfones K11017 and K11777 at 1.8 and 2.5 Å resolutions, respectively. Interactions of the inhibitors with the subsites of the active-site cleft were evaluated by quantum chemical calculations. These data and inhibition profiling with a panel of vinyl sulfone derivatives identify key binding interactions and provide insight into the specificity of SmCB1 inhibition. Furthermore, hydrolysis profiling of SmCB1 using synthetic peptides and the natural substrate hemoglobin revealed that carboxydipeptidase activity predominates over endopeptidolysis, thereby demonstrating the contribution of the occluding loop that restricts access to the active-site cleft. Critically, the severity of phenotypes induced in the parasite by vinyl sulfone inhibitors correlated with enzyme inhibition, providing support that SmCB1 is a valuable drug target. The present structure and inhibitor interaction data provide a footing for the rational design of anti-schistosomal inhibitors.
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Affiliation(s)
- Adéla Jílková
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, 16610 Prague, Czech Republic; Department of Biochemistry, Faculty of Science, Charles University, 12843 Prague, Czech Republic
| | - Pavlína Řezáčová
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, 16610 Prague, Czech Republic; Department of Structural Biology, Institute of Molecular Genetics, Academy of Sciences of the Czech Republic, 16610 Prague, Czech Republic
| | - Martin Lepšík
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, 16610 Prague, Czech Republic
| | - Martin Horn
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, 16610 Prague, Czech Republic
| | - Jana Váchová
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, 16610 Prague, Czech Republic
| | - Jindřich Fanfrlík
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, 16610 Prague, Czech Republic
| | - Jiří Brynda
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, 16610 Prague, Czech Republic; Department of Structural Biology, Institute of Molecular Genetics, Academy of Sciences of the Czech Republic, 16610 Prague, Czech Republic
| | - James H McKerrow
- Sandler Center for Drug Discovery, California Institute for Quantitative Biosciences and Department of Pathology, University of California San Francisco, San Francisco, California 94158
| | - Conor R Caffrey
- Sandler Center for Drug Discovery, California Institute for Quantitative Biosciences and Department of Pathology, University of California San Francisco, San Francisco, California 94158
| | - Michael Mareš
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, 16610 Prague, Czech Republic.
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Nucleoplasmic calcium regulates cell proliferation through legumain. J Hepatol 2011; 55:626-635. [PMID: 21237226 PMCID: PMC3158841 DOI: 10.1016/j.jhep.2010.12.022] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/13/2010] [Revised: 12/09/2010] [Accepted: 12/11/2010] [Indexed: 01/19/2023]
Abstract
BACKGROUND & AIMS Nucleoplasmic Ca(2+) regulates cell growth in the liver, but the proteins through which this occurs are unknown. METHODS We used Rapid Subtraction Hybridization (RaSH) to subtract genes in SKHep1 liver cells expressing the Ca(2+) buffer protein parvalbumin (PV) targeted to the nucleus, from genes in cells expressing a mutated form of nuclear-targeted PV which has one of two Ca(2+)-binding sites inactivated. The subtraction permitted the selection of genes whose expression was affected by a small alteration in nuclear Ca(2+) concentration. RESULTS The asparaginyl endopeptidase legumain (LGMN) was identified in this screening. When Ca(2+) was buffered in the nucleus of SKHep1 cells, LGMN mRNA was decreased by 97%, in part by a transcriptional mechanism, and decreased expression at the protein level was observed by immunoblot and immunofluorescence. Treatment with hepatocyte growth factor increased LGMN expression. Knockdown of LGMN by siRNA decreased proliferation of SKHep1 cells by ∼50% as measured both by BrdU uptake and mitotic index, although an inhibitor of LGMN activity did not affect BrdU incorporation. A significant reduction in the fraction of cells in G2/M phase was seen as well. This was associated with increases in the expression of cyclins A and E. Furthermore, LGMN expression was increased in hepatocellular carcinoma cells relative to normal hepatocytes in the same specimens. CONCLUSIONS These findings suggest a new role for LGMN and provide evidence that nuclear Ca(2+) signals regulate cell proliferation in part through the modulation of LGMN expression. Increased expression of LGMN may be involved in liver carcinogenesis.
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Horn M, Jílková A, Vondrášek J, Marešová L, Caffrey CR, Mareš M. Mapping the pro-peptide of the Schistosoma mansoni cathepsin B1 drug target: modulation of inhibition by heparin and design of mimetic inhibitors. ACS Chem Biol 2011; 6:609-17. [PMID: 21375333 DOI: 10.1021/cb100411v] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Blood flukes of the genus Schistosoma cause the disease schistosomiasis that infects over 200 million people worldwide. Treatment relies on just one drug, and new therapies are needed should drug resistance emerge. Schistosoma mansoni cathepsin B1 (SmCB1) is a gut-associated protease that digests host blood proteins as source of nutrients. It is under evaluation as a therapeutic target. Enzymatic activity of the SmCB1 zymogen is prevented by the pro-peptide that sterically blocks the active site until activation of the zymogen to the mature enzyme. We investigated the structure-inhibition relationships of how the SmCB1 pro-peptide interacts with the enzyme core using a SmCB1 zymogen model and pro-peptide-derived synthetic fragments. Two regions were identified within the pro-peptide that govern its inhibitory interaction with the enzyme core: an "active site region" and a unique "heparin-binding region" that requires heparin. The latter region is apparently only found in the pro-peptides of cathepsins B associated with the gut of trematode parasites. Finally, using the active site region as a template and a docking model of SmCB1, we designed a series of inhibitors mimicking the pro-peptide structure, the best of which yielded low micromolar inhibition constants. Overall, we identify a novel glycosaminoglycan-mediated mechanism of inhibition by the pro-peptide that potentially regulates zymogen activation and describe a promising design strategy to develop antischistosomal drugs.
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Affiliation(s)
- Martin Horn
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo nam. 2, 16610 Prague, Czech Republic
| | - Adéla Jílková
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo nam. 2, 16610 Prague, Czech Republic
- Department of Biochemistry, Faculty of Science, Charles University in Prague, Hlavova 8, 12843 Prague, Czech Republic
| | - Jiří Vondrášek
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo nam. 2, 16610 Prague, Czech Republic
| | - Lucie Marešová
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo nam. 2, 16610 Prague, Czech Republic
| | - Conor R. Caffrey
- Sandler Center for Drug Discovery, California Institute for Quantitative Biosciences (QB3), University of California San Francisco, 1700 Fourth Street, San Francisco, California 94158, United States
| | - Michael Mareš
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo nam. 2, 16610 Prague, Czech Republic
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Cathepsins B1 and B2 of Trichobilharzia SPP., bird schistosomes causing cercarial dermatitis. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2011; 712:136-54. [PMID: 21660663 DOI: 10.1007/978-1-4419-8414-2_9] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Trichobilharzia regenti and T. szidati are schistosomes that infect birds. although T. regenti/T. szidati can only complete their life cycle in specific bird hosts (waterfowl), their larvae-cercariae are able to penetrate, transform and then migrate as schistosomula in nonspecific hosts (e.g., mouse, man). Peptidases are among the key molecules produced by these schistosomes that enable parasite invasion and survival within the host and include cysteine peptidases such as cathepsins B1 and B2. These enzymes are indispensable bio-catalysts in a number of basal biological processes and host-parasite interactions, e.g., tissue invasion/migration, nutrition and immune evasion. Similar biochemical and functional characteristics were observed for cathepsins B1 and B2 in bird schistosomes (T. regenti, T. szidati) and also for their homologs in human schistosomes (Schistosoma mansoni, S. japonicum). Therefore, data obtained in the research of bird schistosomes can also be exploited for the control of human schistosomes such as the search for targets of novel chemotherapeutic drugs and vaccines.
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Identification and functional characterization of legumain in amphioxus Branchiostoma belcheri. Biosci Rep 2009; 30:177-86. [DOI: 10.1042/bsr20090049] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Legumain has been reported from diverse sources such as plants, parasites (animals) and mammals, but little is known in the lower chordates. The present study reports the first characterization of legumain cDNA from the protochordate Branchiostoma belcheri. The deduced 435-amino-acid-long protein is structurally characterized by the presence of a putative N-terminal signal peptide, a peptidase_C13 superfamily domain with the conserved Lys123-Gly124-Asp125 motif and catalytic dyad His153 and Cys195 and two potential Asn-glycosylation sites at Asn85 and Asn270. Phylogenetic analysis demonstrates that B. belcheri legumain forms an independent cluster together with ascidian legumain, and is positioned at the base of vertebrate legumains, suggesting that B. belcheri legumain gene may represent the archetype of vertebrate legumain genes. Both recombinant legumain expressed in yeast and endogenous legumain are able to be converted into active protein of ~37 kDa via a C-terminal autocleavage at acid pH values. The recombinant legumain efficiently degrades the legumain-specific substrate Z-Ala-Ala-Asn-MCA (benzyloxycarbonyl-L-alanyl-L-alanyl-L-asparagine-4-methylcoumaryl-7-amide) at optimum pH 5.5; and the enzymatic activity is inhibited potently by iodoacetamide and N-ethylmaleimide, partially by hen's-egg white cystatin, but not by E-64 [trans-epoxysuccinyl-L-leucylamido-(4-guanidino)butane], PMSF and pepstatin A. In addition, legumain is expressed in vivo in a tissue-specific manner, with main expression in the hepatic caecum and hind-gut of B. belcheri. Altogether, these results suggest that B. belcheri legumain plays a role in the degradation of macromolecules in food.
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Ovat A, Muindi F, Fagan C, Brouner M, Hansell E, Dvořák J, Sojka D, Kopáček P, McKerrow JH, Caffrey CR, Powers JC. Aza-Peptidyl Michael Acceptor and Epoxide Inhibitors—Potent and Selective Inhibitors of Schistosoma mansoni and Ixodes ricinus Legumains (Asparaginyl Endopeptidases). J Med Chem 2009; 52:7192-210. [DOI: 10.1021/jm900849h] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- Asli Ovat
- School of Chemistry and Biochemistry, and the Petit Institute for Bioscience and Bioengineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0400
| | - Fanuel Muindi
- School of Chemistry and Biochemistry, and the Petit Institute for Bioscience and Bioengineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0400
| | - Crystal Fagan
- School of Chemistry and Biochemistry, and the Petit Institute for Bioscience and Bioengineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0400
| | - Michelle Brouner
- School of Chemistry and Biochemistry, and the Petit Institute for Bioscience and Bioengineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0400
| | - Elizabeth Hansell
- Sandler Center for Basic Research in Parasitic Diseases, California Institute for Quantitative Biosciences, University of California, San Francisco, California 94158
| | - Jan Dvořák
- Sandler Center for Basic Research in Parasitic Diseases, California Institute for Quantitative Biosciences, University of California, San Francisco, California 94158
| | - Daniel Sojka
- Institute of Parasitology, Biology Centre of the Academy of Sciences of the Czech Republic, České Budějovice, CZ-370 05, Czech Republic
| | - Petr Kopáček
- Institute of Parasitology, Biology Centre of the Academy of Sciences of the Czech Republic, České Budějovice, CZ-370 05, Czech Republic
| | - James H. McKerrow
- Sandler Center for Basic Research in Parasitic Diseases, California Institute for Quantitative Biosciences, University of California, San Francisco, California 94158
| | - Conor R. Caffrey
- Sandler Center for Basic Research in Parasitic Diseases, California Institute for Quantitative Biosciences, University of California, San Francisco, California 94158
| | - James C. Powers
- School of Chemistry and Biochemistry, and the Petit Institute for Bioscience and Bioengineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0400
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30
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Ju JW, Joo HN, Lee MR, Cho SH, Cheun HI, Kim JY, Lee YH, Lee KJ, Sohn WM, Kim DM, Kim IC, Park BC, Kim TS. Identification of a serodiagnostic antigen, legumain, by immunoproteomic analysis of excretory-secretory products of Clonorchis sinensis
adult worms. Proteomics 2009; 9:3066-78. [DOI: 10.1002/pmic.200700613] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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31
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Kašný M, Mikeš L, Hampl V, Dvořák J, Caffrey CR, Dalton JP, Horák P. Chapter 4 Peptidases of Trematodes. ADVANCES IN PARASITOLOGY 2009; 69:205-97. [DOI: 10.1016/s0065-308x(09)69004-7] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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32
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Laha T, Sripa J, Sripa B, Pearson M, Tribolet L, Kaewkes S, Sithithaworn P, Brindley PJ, Loukas A. Asparaginyl endopeptidase from the carcinogenic liver fluke, Opisthorchis viverrini, and its potential for serodiagnosis. Int J Infect Dis 2008; 12:e49-59. [PMID: 18619888 PMCID: PMC2670890 DOI: 10.1016/j.ijid.2008.03.033] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2008] [Revised: 03/05/2008] [Accepted: 03/18/2008] [Indexed: 12/18/2022] Open
Abstract
OBJECTIVES To isolate and characterize an asparaginyl endopeptidase from the carcinogenic liver fluke, Opisthorchis viverrini, and evaluate its expression profile, biochemical activity, and potential as an immunodiagnostic antigen. METHODS The full length mRNA encoding an asparaginyl endopeptidase (family C13), Ov-aep-1, was isolated by immunoscreening of a cDNA bacteriophage library of adult O. viverrini using sera from patients infected with O. viverrini. Investigation of Ov-aep-1 transcripts in developmental stages of the parasite, and phylogenetic analysis, immunohistochemical localization, and recombinant protein expression and enzymology were employed to characterize the Ov-AEP-1 protein. Immunoblotting was used to assess the potential of this enzyme for immunodiagnosis of human opisthorchiasis. RESULTS Ov-AEP-1 is characteristic of the C13 cysteine protease family. Ov-aep-1 transcripts were detected in adult and juvenile worms, eggs, and metacercariae. Phylogenetic analysis indicated that Ov-AEP-1 is closely related to homologous proteins in other trematodes. Recombinant Ov-AEP-1 was expressed in bacteria in inclusion bodies and refolded to a soluble form. Excretory-secretory (ES) products derived from adult O. viverrini and refolded recombinant Ov-AEP-1 both displayed catalytic activity against the diagnostic tripeptide substrate, Ala-Ala-Asn-aminomethylcoumarin. Rabbit antiserum raised to recombinant Ov-AEP-1 identified the native AEP-1 protease in both somatic extract and ES products of adult worms. Anti-Ov-AEP-1 IgG immunolocalized the anatomical site of expression to the gut of the fluke, implying a physiological role in digestion of food or activation of other digestive enzymes. Recombinant Ov-AEP-1 was recognized by serum antibodies from patients with opisthorchiasis but not other helminth infections, with a sensitivity and specificity of 85% and 100%, respectively. The positive and negative predictive values are 100% and 67%, respectively. CONCLUSIONS The liver fluke, O. viverrini, has a gut-localized asparaginyl endopeptidase. Refolded recombinant Ov-AEP-1 is catalytically active and has potential for immunodiagnosis of human opisthorchiasis.
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Affiliation(s)
- Thewarach Laha
- Department of Parasitology, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand.
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Götz MG, James KE, Hansell E, Dvořák J, Seshaadri A, Sojka D, Kopáček P, McKerrow JH, Caffrey CR, Powers JC. Aza-peptidyl Michael Acceptors. A New Class of Potent and Selective Inhibitors of Asparaginyl Endopeptidases (Legumains) from Evolutionarily Diverse Pathogens. J Med Chem 2008; 51:2816-32. [DOI: 10.1021/jm701311r] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Affiliation(s)
- Marion G. Götz
- School of Chemistry and Biochemistry and the Petit Institute for Bioscience and Bioengineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0400, Sandler Center for Basic Research in Parasitic Diseases, Byers Hall, University of California San Francisco, San Francisco, California 94158, Institute of Parasitology, Biology Centre of the Academy of Sciences of the Czech Republic, České Budějovice, CZ-370 05, Czech Republic, and Department of Chemistry, Whitman College, 345 Boyer Avenue, Walla
| | - Karen Ellis James
- School of Chemistry and Biochemistry and the Petit Institute for Bioscience and Bioengineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0400, Sandler Center for Basic Research in Parasitic Diseases, Byers Hall, University of California San Francisco, San Francisco, California 94158, Institute of Parasitology, Biology Centre of the Academy of Sciences of the Czech Republic, České Budějovice, CZ-370 05, Czech Republic, and Department of Chemistry, Whitman College, 345 Boyer Avenue, Walla
| | - Elizabeth Hansell
- School of Chemistry and Biochemistry and the Petit Institute for Bioscience and Bioengineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0400, Sandler Center for Basic Research in Parasitic Diseases, Byers Hall, University of California San Francisco, San Francisco, California 94158, Institute of Parasitology, Biology Centre of the Academy of Sciences of the Czech Republic, České Budějovice, CZ-370 05, Czech Republic, and Department of Chemistry, Whitman College, 345 Boyer Avenue, Walla
| | - Jan Dvořák
- School of Chemistry and Biochemistry and the Petit Institute for Bioscience and Bioengineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0400, Sandler Center for Basic Research in Parasitic Diseases, Byers Hall, University of California San Francisco, San Francisco, California 94158, Institute of Parasitology, Biology Centre of the Academy of Sciences of the Czech Republic, České Budějovice, CZ-370 05, Czech Republic, and Department of Chemistry, Whitman College, 345 Boyer Avenue, Walla
| | - Amritha Seshaadri
- School of Chemistry and Biochemistry and the Petit Institute for Bioscience and Bioengineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0400, Sandler Center for Basic Research in Parasitic Diseases, Byers Hall, University of California San Francisco, San Francisco, California 94158, Institute of Parasitology, Biology Centre of the Academy of Sciences of the Czech Republic, České Budějovice, CZ-370 05, Czech Republic, and Department of Chemistry, Whitman College, 345 Boyer Avenue, Walla
| | - Daniel Sojka
- School of Chemistry and Biochemistry and the Petit Institute for Bioscience and Bioengineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0400, Sandler Center for Basic Research in Parasitic Diseases, Byers Hall, University of California San Francisco, San Francisco, California 94158, Institute of Parasitology, Biology Centre of the Academy of Sciences of the Czech Republic, České Budějovice, CZ-370 05, Czech Republic, and Department of Chemistry, Whitman College, 345 Boyer Avenue, Walla
| | - Petr Kopáček
- School of Chemistry and Biochemistry and the Petit Institute for Bioscience and Bioengineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0400, Sandler Center for Basic Research in Parasitic Diseases, Byers Hall, University of California San Francisco, San Francisco, California 94158, Institute of Parasitology, Biology Centre of the Academy of Sciences of the Czech Republic, České Budějovice, CZ-370 05, Czech Republic, and Department of Chemistry, Whitman College, 345 Boyer Avenue, Walla
| | - James H. McKerrow
- School of Chemistry and Biochemistry and the Petit Institute for Bioscience and Bioengineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0400, Sandler Center for Basic Research in Parasitic Diseases, Byers Hall, University of California San Francisco, San Francisco, California 94158, Institute of Parasitology, Biology Centre of the Academy of Sciences of the Czech Republic, České Budějovice, CZ-370 05, Czech Republic, and Department of Chemistry, Whitman College, 345 Boyer Avenue, Walla
| | - Conor R. Caffrey
- School of Chemistry and Biochemistry and the Petit Institute for Bioscience and Bioengineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0400, Sandler Center for Basic Research in Parasitic Diseases, Byers Hall, University of California San Francisco, San Francisco, California 94158, Institute of Parasitology, Biology Centre of the Academy of Sciences of the Czech Republic, České Budějovice, CZ-370 05, Czech Republic, and Department of Chemistry, Whitman College, 345 Boyer Avenue, Walla
| | - James C. Powers
- School of Chemistry and Biochemistry and the Petit Institute for Bioscience and Bioengineering, Georgia Institute of Technology, Atlanta, Georgia 30332-0400, Sandler Center for Basic Research in Parasitic Diseases, Byers Hall, University of California San Francisco, San Francisco, California 94158, Institute of Parasitology, Biology Centre of the Academy of Sciences of the Czech Republic, České Budějovice, CZ-370 05, Czech Republic, and Department of Chemistry, Whitman College, 345 Boyer Avenue, Walla
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Krautz-Peterson G, Skelly PJ. Schistosome asparaginyl endopeptidase (legumain) is not essential for cathepsin B1 activation in vivo. Mol Biochem Parasitol 2008; 159:54-8. [PMID: 18280591 DOI: 10.1016/j.molbiopara.2007.12.011] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2007] [Revised: 12/21/2007] [Accepted: 12/28/2007] [Indexed: 11/17/2022]
Abstract
Schistosomes are parasitic platyhelminths that constitute an important public health problem. Adult parasites live in the vasculature of their vertebrate hosts where they consume blood. Ingested blood proteins are degraded by a proteolytic cascade. One of the best characterized schistosome proteases is cathepsin B1 (SmCB1 or Sm31). This protein is synthesized as a large 38 kDa precursor form which is proteolytically cleaved to yield a mature, active 31 kDa enzyme. A second schistosome protease--the asparaginyl endopeptidase SmAE (also known as Sm32, or schistosome legumain), has been proposed to proteolytically convert the 38 kDa precursor SmCB1 into its mature form. Recombinant activated SmAE has been shown to trans-process SmCB1 into the mature, catalytic form in vitro. In the present study, our aim was to test the hypothesis that in vivo SmAE likewise processes SmCB1 into its active form. To do this, expression of the SmAE gene was suppressed in adult Schistosoma mansoni using RNA interference (RNAi). The results of these experiments show that, even in the absence of detectable SmAE protein, SmCB1 is fully processed and active and support the assertion that SmAE is not essential to activate SmCB1 in vivo. The data indicate that our original hypothesis is incorrect and that SmAE is not pivotal in the in vivo conversion of cathepsin B1 into its mature, active form.
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Affiliation(s)
- Greice Krautz-Peterson
- Molecular Helminthology Laboratory, Division of Infectious Diseases, Department of Biomedical Sciences, Tufts University, Cummings School of Veterinary Medicine, Grafton, MA 01536, USA
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Adisakwattana P, Viyanant V, Chaicumpa W, Vichasri-Grams S, Hofmann A, Korge G, Sobhon P, Grams R. Comparative molecular analysis of two asparaginyl endopeptidases and encoding genes from Fasciola gigantica. Mol Biochem Parasitol 2007; 156:102-16. [PMID: 17714804 DOI: 10.1016/j.molbiopara.2007.07.006] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2007] [Revised: 07/03/2007] [Accepted: 07/11/2007] [Indexed: 12/07/2022]
Abstract
In this study we describe the first cysteine proteinases of the MEROPS Clan CD family C13 in Fasciola gigantica. Family C13 contains asparaginyl endopeptidases and glycosylphosphatidylinositol-anchor transamidases and is also called the legumain family due to the discovery of the first asparaginyl endopeptidase in a legume. The cDNAs encoding two asparaginyl endopeptidases, FgLGMN-1 and FgLGMN-2, were cloned and used for the analysis of nucleic acid and protein properties. The deduced amino acid sequences showed 47.4% identity to each other and from 42.2 to 51.1% identity to homologs of other trematode species. The catalytic site residues histidine, cysteine and preceding hydrophobic residues, characteristic for the cysteine proteinase families C11, C13, C14, and C25, were found conserved. Northern and reverse transcription PCR analyses demonstrated that the transcriptional products are present in metacercariae, juveniles and adults. RNA in situ hybridization and immunohistochemistry revealed that RNA and protein products of the two genes are specifically expressed in the intestinal epithelium of juveniles and adults. Immune sera of mice infected with F. gigantica reacted with immunoblotted, bacterially expressed recombinant proteins starting 4 weeks after infection. Polyclonal antisera raised against the recombinant proteins detected 40 and 30 kDa antigens, respectively in crude worm protein extracts but not in the excretion-secretion products of adult parasites. Likewise, legumain-specific activity was found in crude worm protein extracts but not in excretion-secretion products. This study elucidates the molecular characteristics of these proteins in F. gigantica and demonstrates differences in the biology between Fasciola and Schistosoma which may prove useful for the development of vaccines against fasciolosis in domestic livestock.
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MESH Headings
- Amino Acid Sequence
- Animals
- Antibodies, Helminth/immunology
- Blotting, Northern
- Catalytic Domain/genetics
- Cattle
- Cattle Diseases/parasitology
- Cloning, Molecular
- Conserved Sequence/genetics
- Cysteine Endopeptidases/genetics
- Cysteine Endopeptidases/immunology
- DNA, Complementary/genetics
- DNA, Complementary/isolation & purification
- DNA, Helminth/chemistry
- DNA, Helminth/genetics
- DNA, Helminth/isolation & purification
- Fasciola/enzymology
- Fasciola/genetics
- Fasciola/immunology
- Fasciola/isolation & purification
- Fascioliasis/parasitology
- Fascioliasis/veterinary
- Gene Expression
- Immunohistochemistry
- In Situ Hybridization
- Intestinal Mucosa/parasitology
- Mice
- Mice, Inbred BALB C
- Molecular Sequence Data
- RNA, Messenger/biosynthesis
- Reverse Transcriptase Polymerase Chain Reaction
- Sequence Analysis, DNA
- Sequence Homology, Amino Acid
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Affiliation(s)
- Poom Adisakwattana
- Faculty of Allied Health Sciences, Thammasat University, Pathumthani, Thailand
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36
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Delcroix M, Medzihradsky K, Caffrey CR, Fetter RD, McKerrow JH. Proteomic analysis of adult S. mansoni gut contents. Mol Biochem Parasitol 2007; 154:95-7. [PMID: 17451823 PMCID: PMC2732360 DOI: 10.1016/j.molbiopara.2007.03.008] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2007] [Revised: 03/12/2007] [Accepted: 03/13/2007] [Indexed: 11/19/2022]
Affiliation(s)
- Melaine Delcroix
- Sandler Center for Basic Research in Parasitic Diseases, California Institute for Quantitative Biomedical Research (QB3), 1700 4th St., University of California, San Francisco, CA 94158-2330, USA
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37
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Sojka D, Hajdušek O, Dvořák J, Sajid M, Franta Z, Schneider EL, Craik CS, Vancová M, Burešová V, Bogyo M, Sexton KB, McKerrow JH, Caffrey CR, Kopáček P. IrAE: an asparaginyl endopeptidase (legumain) in the gut of the hard tick Ixodes ricinus. Int J Parasitol 2007; 37:713-24. [PMID: 17336985 PMCID: PMC2587490 DOI: 10.1016/j.ijpara.2006.12.020] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2006] [Revised: 12/11/2006] [Accepted: 12/12/2006] [Indexed: 10/23/2022]
Abstract
Ticks are ectoparasitic blood-feeders and important vectors for pathogens including arboviruses, rickettsiae, spirochetes and protozoa. As obligate blood-feeders, one possible strategy to retard disease transmission is disruption of the parasite's ability to digest host proteins. However, the constituent peptidases in the parasite gut and their potential interplay in the digestion of the blood meal are poorly understood. We have characterised a novel asparaginyl endopeptidase (legumain) from the hard tick Ixodes ricinus (termed IrAE), which we believe is the first such characterisation of a clan CD family C13 cysteine peptidase (protease) in arthropods. By RT-PCR of different tissues, IrAE mRNA was only expressed in the tick gut. Indirect immunofluorescence and EM localised IrAE in the digestive vesicles of gut cells and within the peritrophic matrix. IrAE was functionally expressed in Pichia pastoris and reacted with a specific peptidyl fluorogenic substrate, and acyloxymethyl ketone and aza-asparagine Michael acceptor inhibitors. IrAE activity was unstable at pH > or = 6.0 and was shown to have a strict specificity for asparagine at P1 using a positional scanning synthetic combinatorial library. The enzyme hydrolyzed protein substrates with a pH optimum of 4.5, consistent with the pH of gut cell digestive vesicles. Thus, IrAE cleaved the major protein of the blood meal, hemoglobin, to a predominant peptide of 4kDa. Also, IrAE trans-processed and activated the zymogen form of Schistosoma mansoni cathepsin B1 -- an enzyme contributing to hemoglobin digestion in the gut of that bloodfluke. The possible functions of IrAE in the gut digestive processes of I. ricinus are compared with those suggested for other hematophagous parasites.
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Affiliation(s)
- Daniel Sojka
- Institute of Parasitology, Biology Centre of the Academy of Sciences of the Czech Republic and Faculty of Biological Sciences, University of South Bohemia, České Budějovice, CZ-370 05, The Czech Republic
| | - Ondřej Hajdušek
- Institute of Parasitology, Biology Centre of the Academy of Sciences of the Czech Republic and Faculty of Biological Sciences, University of South Bohemia, České Budějovice, CZ-370 05, The Czech Republic
| | - Jan Dvořák
- Sandler Center for Basic Research in Parasitic Diseases, University of California San Francisco, San Francisco, CA 94158, USA
| | - Mohammed Sajid
- Sandler Center for Basic Research in Parasitic Diseases, University of California San Francisco, San Francisco, CA 94158, USA
| | - Zdeněk Franta
- Institute of Parasitology, Biology Centre of the Academy of Sciences of the Czech Republic and Faculty of Biological Sciences, University of South Bohemia, České Budějovice, CZ-370 05, The Czech Republic
| | - Eric L. Schneider
- Department of Pharmaceutical Chemistry, University of California San Francisco, San Francisco, CA 94720, USA
| | - Charles S. Craik
- Department of Pharmaceutical Chemistry, University of California San Francisco, San Francisco, CA 94720, USA
| | - Marie Vancová
- Institute of Parasitology, Biology Centre of the Academy of Sciences of the Czech Republic and Faculty of Biological Sciences, University of South Bohemia, České Budějovice, CZ-370 05, The Czech Republic
| | - Veronika Burešová
- Institute of Parasitology, Biology Centre of the Academy of Sciences of the Czech Republic and Faculty of Biological Sciences, University of South Bohemia, České Budějovice, CZ-370 05, The Czech Republic
| | - Matthew Bogyo
- Department of Pathology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Kelly B. Sexton
- Department of Pathology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - James H. McKerrow
- Sandler Center for Basic Research in Parasitic Diseases, University of California San Francisco, San Francisco, CA 94158, USA
| | - Conor R. Caffrey
- Sandler Center for Basic Research in Parasitic Diseases, University of California San Francisco, San Francisco, CA 94158, USA
| | - Petr Kopáček
- Institute of Parasitology, Biology Centre of the Academy of Sciences of the Czech Republic and Faculty of Biological Sciences, University of South Bohemia, České Budějovice, CZ-370 05, The Czech Republic
- Correspondence to: P. Kopáček, Institute of Parasitology, Biology Centre ASCR, Branišovská 31, CZ-370 05 České Budějovice, Czech Republic. E-mail:
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38
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Delcroix M, Sajid M, Caffrey CR, Lim KC, Dvorák J, Hsieh I, Bahgat M, Dissous C, McKerrow JH. A Multienzyme Network Functions in Intestinal Protein Digestion by a Platyhelminth Parasite. J Biol Chem 2006; 281:39316-29. [PMID: 17028179 DOI: 10.1074/jbc.m607128200] [Citation(s) in RCA: 179] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Proteases frequently function not only as individual enzymes but also in cascades or networks. A notable evolutionary switch occurred in one such protease network that is involved in protein digestion in the intestine. In vertebrates, this is largely the work of trypsin family serine proteases, whereas in invertebrates, cysteine proteases of the papain family and aspartic proteases assume the role. Utilizing a combination of protease class-specific inhibitors and RNA interference, we deconvoluted such a network of major endopeptidases functioning in invertebrate intestinal protein digestion, using the parasitic helminth, Schistosoma mansoni as an experimental model. We show that initial degradation of host blood proteins is ordered, occasionally redundant, and substrate-specific. Although inhibition of parasite cathepsin D had a greater effect on primary cleavage of hemoglobin, inhibition of cathepsin B predominated in albumin degradation. Nevertheless, in both cases, inhibitor combinations were synergistic. An asparaginyl endopeptidase (legumain) also synergized with cathepsin B and L in protein digestion, either by zymogen activation or facilitating substrate cleavage. This protease network operates optimally in acidic pH compartments either in the gut lumen or in vacuoles of the intestinal lining cells. Defining the role of each of these major enzymes now provides a clearer understanding of the function of a complex protease network that is conserved throughout invertebrate evolution. It also provides insights into which of these proteases are logical targets for development of chemotherapy for schistosomiasis, a major global health problem.
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Affiliation(s)
- Melaine Delcroix
- Department of Pathology, Tropical Disease Research Unit and Sandler Center for Basic Research in Parasitic Diseases, University of California, San Francisco, California 94158, USA.
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39
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Beckham SA, Law RHP, Smooker PM, Quinsey NS, Caffrey CR, McKerrow JH, Pike RN, Spithill TW. Production and processing of a recombinant Fasciola hepatica cathepsin B-like enzyme (FhcatB1) reveals potential processing mechanisms in the parasite. Biol Chem 2006; 387:1053-61. [PMID: 16895475 DOI: 10.1515/bc.2006.130] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
AbstractThe liver fluke,Fasciola hepatica, apparently uses a number of cysteine proteases during its life cycle, most likely for feeding, immune evasion and invasion of tissues. A cathepsin B-like enzyme (herein referred to as FhcatB1) appears to be a major enzyme secreted by the invasive, newly excysted juvenile flukes of this parasite. To examine the processing mechanisms for this enzyme, a recombinant form was expressed inPichia pastorisand purified to yield a homogenous pool of the enzyme. The purified enzyme could be autoactivated at low pH via a bi-molecular mechanism, a process that was greatly accelerated by the presence of large, negatively charged molecules such as dextran sulfate. The enzyme could also apparently be processed to the correct size by an asparaginyl endopeptidase via cleavage in an unusual insertion N-terminal to the normal cleavage site used to yield the active form of the enzyme. Thus, there appear to be a number of ways in which this enzyme can be processed to its optimally active form prior to secretion byF. hepatica.
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Affiliation(s)
- Simone A Beckham
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria 3800, Australia
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40
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Oliver EM, Skuce PJ, McNair CM, Knox DP. Identification and characterization of an asparaginyl proteinase (legumain) from the parasitic nematode, Haemonchus contortus. Parasitology 2006; 133:237-44. [PMID: 16650340 DOI: 10.1017/s0031182006000229] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2006] [Revised: 02/27/2006] [Accepted: 02/28/2006] [Indexed: 11/06/2022]
Abstract
Asparaginyl proteinases (or legumains) are a recently identified, novel class of cysteine proteinase which specifically hydrolyse peptide bonds after asparagine residues. Legumains have been implicated in the activation of cysteine proteases, particularly cathepsin B-like proteinases which are thought to help degrade the bloodmeal in blood-feeding helminths such as schistosomes, hookworms and other nematode species. An EST sequence representing a full-length legumain was identified from the Haemonchus contortus dataset. This encoded a protein with a predicted Mr of 49 kDa, the amino acid sequence of which showed good homology (34-40% identity) to legumains from Schistosoma mansoni, human and rat and contained a legumain-like active site. RT-PCR indicated that the legumain transcript was expressed from the L4 life-cycle stage onwards. The coding sequence was expressed in E. coli and antibodies to the resultant recombinant protein indicated that the enzyme was expressed in the microvillar surface of the intestinal cells. Legumain activity was detected in extracts of the adult parasite but not the host protective Thiol-Sepharose-binding fraction, although it was detectable in the latter by immunoblot. Activity was relatively insensitive to E64, an inhibitor of cysteine proteinases and completely inhibited by the alkylating agent, N-ethylmaleimide, consistent with inhibitor effects on previously characterized legumains.
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Affiliation(s)
- E M Oliver
- Moredun Research Institute, Pentlands Science Park, Bush Loan, Penicuik, Midlothian EH26 0PZ, UK
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41
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Losada S, Chacón N, Colmenares C, Bermúdez H, Lorenzo A, Pointier JP, Theron A, Alarcón de Noya B, Noya O. Schistosoma: Cross-reactivity and antigenic community among different species. Exp Parasitol 2005; 111:182-90. [PMID: 16165128 DOI: 10.1016/j.exppara.2005.07.007] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2005] [Revised: 07/22/2005] [Accepted: 07/26/2005] [Indexed: 11/21/2022]
Abstract
It is not unusual to find common molecules among different species of the genus Schistosoma. When those molecules are antigenic, they may be used in immunodiagnosis and vaccines, but they could also be applied to taxonomic and evolutionary studies. To study cross-reactivity and antigenic community among different species of schistosomes, plasmas from laboratory animals infected with Schistosoma bovis, S. guineensis, S. rodhaini, S. haematobium, and four strains of S. mansoni were evaluated with a crude extract of adult worms of S. mansoni by Western blot. Using the multiple antigen blot assay, plasmas from these infected animals were exposed to a selected group of synthetic peptides from Sm28GST, Sm28TPI, Sm elastase, Sm97, Sm32, Sm31, and Sm Cathepsin L. The results presented herein demonstrate differential cross-reactivity and antigenic community among the Mansoni and Haematobium groups of schistosomes, which is of relevance as an additional new tool for phylogenetic studies of schistosomes as well as for diagnosis and vaccine purposes.
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Affiliation(s)
- S Losada
- Sección de Biohelmintiasis, Instituto de Medicina Tropical, Escuela de Medicina Luis Razetti, Facultad de Medicina, Universidad Central de Venezuela, Apartado 47623, Los Chaguaramos 1041-A, Caracas, Venezuela.
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42
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Dvorák J, Delcroix M, Rossi A, Vopálenský V, Pospísek M, Sedinová M, Mikes L, Sajid M, Sali A, McKerrow JH, Horák P, Caffrey CR. Multiple cathepsin B isoforms in schistosomula of Trichobilharzia regenti: identification, characterisation and putative role in migration and nutrition. Int J Parasitol 2005; 35:895-910. [PMID: 15950230 DOI: 10.1016/j.ijpara.2005.02.018] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2004] [Revised: 02/07/2005] [Accepted: 02/21/2005] [Indexed: 11/20/2022]
Abstract
Among schistosomatids, Trichobilharzia regenti, displays an unusual migration through the peripheral and central nervous system prior to residence in the nasal cavity of the definitive avian host. Migration causes tissue degradation and neuromotor dysfunction both in birds and experimentally infected mice. Although schistosomula have a well-developed gut, the peptidases elaborated that might facilitate nutrition and migration are unknown. This is, in large part, due to the difficulty in isolating large numbers of migrating larvae. We have identified and characterised the major 33 kDa cathepsin B-like cysteine endopeptidase in extracts of migrating schistosomula using fluorogenic peptidyl substrates with high extinction coefficients and irreversible affinity-labels. From first strand schistosomula cDNA, degenerate PCR and Rapid Amplification of cDNA End protocols were used to identify peptidase isoforms termed TrCB1.1-TrCB1.6. Highest sequence homology is to the described Schistosoma mansoni and Schistosoma japonicum cathepsins B1. Two isoforms (TrCB1.5 and 1.6) encode putatively inactive enzymes as the catalytic cysteine is substituted by glycine. Two other isoforms, TrCB1.1 and 1.4, were functionally expressed as zymogens in Pichia pastoris. Specific polyclonal antibodies localised the peptidases exclusively in the gut of schistosomula and reacted with a 33kDa protein in worm extracts. TrCB1.1 zymogen was unable to catalyse its own activation, but was trans-processed and activated by S. mansoni asparaginyl endopeptidase (SmAE aka. S. mansoni legumain). In contrast, TrCB1.4 zymogen auto-activated, but was resistant to the action of SmAE. Both activated isoforms displayed different pH-dependent specificity profiles with peptidyl substrates. Also, both isoforms degraded myelin basic protein, the major protein component of nervous tissue, but were inefficient against hemoglobin, thus supporting the adaptation of T. regenti gut peptidases to parasitism of host nervous tissue.
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Affiliation(s)
- Jan Dvorák
- Department of Parasitology, Faculty of Science, Charles University, Vinicná 7, CZ 12844 Prague, Czech Republic
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43
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Caffrey CR, McKerrow JH, Salter JP, Sajid M. Blood ‘n’ guts: an update on schistosome digestive peptidases. Trends Parasitol 2004; 20:241-8. [PMID: 15105025 DOI: 10.1016/j.pt.2004.03.004] [Citation(s) in RCA: 120] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- Conor R Caffrey
- Sandler Center for Basic Research in Parasitic Diseases, Box 0511, University of California-San Francisco, San Francisco, CA 94143, USA.
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44
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Ekici OD, Götz MG, James KE, Li ZZ, Rukamp BJ, Asgian JL, Caffrey CR, Hansell E, Dvorák J, McKerrow JH, Potempa J, Travis J, Mikolajczyk J, Salvesen GS, Powers JC. Aza-Peptide Michael Acceptors: A New Class of Inhibitors Specific for Caspases and Other Clan CD Cysteine Proteases. J Med Chem 2004; 47:1889-92. [PMID: 15055989 DOI: 10.1021/jm049938j] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Aza-peptide Michael acceptors are a new class of irreversible inhibitors that are highly potent and specific for clan CD cysteine proteases. The aza-Asp derivatives were specific for caspases, while aza-Asn derivatives were effective legumain inhibitors. Aza-Lys and aza-Orn derivatives were potent inhibitors of gingipain K and clostripain. Aza-peptide Michael acceptors showed no cross reactivity toward papain, cathepsin B, and calpain.
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Affiliation(s)
- Ozlem Doğan Ekici
- School of Chemistry and Biochemistry and the Parker H. Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA 30332-0400, USA
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45
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Law RHP, Smooker PM, Irving JA, Piedrafita D, Ponting R, Kennedy NJ, Whisstock JC, Pike RN, Spithill TW. Cloning and expression of the major secreted cathepsin B-like protein from juvenile Fasciola hepatica and analysis of immunogenicity following liver fluke infection. Infect Immun 2004; 71:6921-32. [PMID: 14638781 PMCID: PMC308908 DOI: 10.1128/iai.71.12.6921-6932.2003] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The functions of the cathepsin B-like proteases in liver flukes are unknown and analysis has been hindered by a lack of protein for study, since the protein is produced in small amounts by juvenile flukes. To circumvent this, we isolated and characterized a cDNA encoding the major secreted cathepsin B from Fasciola hepatica. The predicted preproprotein is 339 amino acids in length, with the mature protease predicted to be 254 amino acids long, and shows significant similarity to parasite and mammalian cathepsin B. Only one of the two conserved histidine residues required for cathepsin B exopeptidase activity is predicted to be present. Recombinant preproprotein was produced in yeast, and it was shown that the recombinant proprotein can undergo a degree of self-processing in vitro to the mature form, which is active against gelatin and synthetic peptide substrates. The recombinant protein is antigenic in vaccinated rats, and antibodies to the protein are detected early after infection of rats and sheep with F. hepatica. The kinetics of the response to cathepsin B and cathepsin L after infection of sheep and rats confirm the temporal expression of these proteins during the life cycle of the parasite.
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Affiliation(s)
- Ruby H P Law
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, Australia
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46
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James KE, Götz MG, Caffrey CR, Hansell E, Carter W, Barrett AJ, McKerrow JH, Powers JC. Aza-Peptide Epoxides: Potent and Selective Inhibitors of Schistosoma mansoni and Pig Kidney Legumains (Asparaginyl Endopeptidases). Biol Chem 2003; 384:1613-8. [PMID: 14719804 DOI: 10.1515/bc.2003.179] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
Aza-peptide epoxides are a new class of irreversible
cysteine protease inhibitors. Derivatives containing a
P1 aza-asparagine residue are specific for Schistosoma
mansoni and pig kidney legumains, which are clan
CD cysteine proteases. The inhibitors have secondorder
rate constants of up to 104 M-1s -1 with pig kidney
legumain and IC50 values as low as 45 nM with S.
mansoni legumain. The most potent epoxides contain
an ester moiety with S,S stereochemistry attached to
the epoxide. Interestingly, amide and amino acid derivatives
of the epoxysuccinate moiety were not inhibitors
of legumain, while disubstituted amide derivatives
are quite potent. The inhibitors have little or no
inhibitory activity with other proteases such as caspases,
chymotrypsin, papain, cathepsin B, granzyme
B, and various aspartyl proteases.
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Affiliation(s)
- Karen Ellis James
- School of Chemistry and Biochemistry, and the Petit Institute for Bioscience and Bioengineering, Georgia Institute of Technology, Atlanta, GA 30332-0400, USA
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47
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Li DN, Matthews SP, Antoniou AN, Mazzeo D, Watts C. Multistep autoactivation of asparaginyl endopeptidase in vitro and in vivo. J Biol Chem 2003; 278:38980-90. [PMID: 12860980 DOI: 10.1074/jbc.m305930200] [Citation(s) in RCA: 140] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Mammalian asparaginyl endopeptidase (AEP) or legumain is a recently discovered lysosomal cysteine protease that specifically cleaves after asparagine residues. How this unusually specific lysosomal protease is itself activated is not fully understood. Using purified recombinant pro-enzyme, we show that activation is autocatalytic, requires sequential removal of C- and N-terminal pro-peptides at different pH thresholds, and is bimolecular. Removal of the N-terminal propeptide requires cleavage after aspartic acid rather than asparagine. Cellular processing, either of exogenously added AEP precursor or of pulse-labeled endogenous precursor, introduces at least one further cleavage to yield the final mature lysosomal enzyme. We also provide evidence that in living cells, there is clear compartmental heterogeneity in terms of AEP activation status. Moreover, we show that human monocyte-derived dendritic cells harbor inactive proforms of AEP that become activated upon maturation of dendritic cells with lipopolysaccharide.
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Affiliation(s)
- Dongtao Ni Li
- Division of Cell Biology & Immunology, Wellcome Trust Biocentre, School of Life Sciences, University of Dundee, Dundee, DD1 5EH, United Kingdom
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48
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Chacón N, Losada S, Bermúdez H, Cesari IM, Hoebeke J, Noya O. Immunogenicity of polymerizable synthetic peptides derived from a vaccine candidate against schistosomiasis: the asparaginyl endopeptidase (Sm32). Immunol Lett 2003; 88:199-210. [PMID: 12941479 DOI: 10.1016/s0165-2478(03)00084-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The asparaginyl endopeptidase (Sm32) is expressed in the gastrodermal cells of the schistosome gut and in the head glands of the cercariae. Possibly, Sm32 hydrolyzes pro-proteins involved in the degradation of host hemoglobin [Parasitol. Today 12 (1996) 125]. Preliminary evidences using an Sj32/Sm32 murine vaccine have shown a profound effect on oviposition and worm burden [Chin. J. Schist. Control. 7 (1995) 72; Bull. Human Med. Univ. 24 (1999) 225; Vaccine 20 (2002) 439]. The importance of Sm32 as a novel vaccine candidate is based on the possibility of preventing the maturation of other cathepsins and/or preventing schistosome skin invasion. We studied the immunogenicity of polymerizable peptides derived from Sm32 to select potential protective epitopes. Sm32 prediction of T and B epitopes and homology studies with human legumain were performed. Among the variety of factors that influence the antibody response, we specifically examined the effect of: (i) genetic background of mouse strain, inbred (C57BL/6) versus outbred (Swiss) mice; and (ii) vaccination with a single peptide versus pool of peptides. Swiss mice raised antibodies to three different regions of the Sm32, as tested by the Multiple Antigen Blot Assay (MABA): 182-215 (peptides IMT-70 and 72), 244-273 (IMT-64) and 336-355 (IMT-66). None of these regions were immunogenic for C57BL/6. On the contrary, other peptides, IMT-4 (21-40), IMT-12 (101-120) and IMT-26 (292-313) were highly immunogenic for this inbred strain. Only Swiss mice immunized with a single peptide (IMT-64 and 72) or with three different pools of IMT-peptides (Pool A-II: 14, 16, 18, 70, 72, 89; pool A-III: 22, 64, 24, 26, 28 and pool A-V: 64, 66, 28, 70, 72) recognized the original protein in a crude extract of the worm antigen by Western blot. Peptides IMT-64, 14 and 26 were responsible for this recognition. In general, the vaccination with pool of peptides was more immunogenic for both mouse strains. Predicted B cell epitopes, with hydrophilicity scores over +10 (IMT-12, 64, 26) were always immunogenic after either single or combined peptide vaccination. Sm32 sequences 41-80 (IMT-6 and 8), 141-160 (IMT-16) and 182-215 (IMT-70 and 72) were nearly identical to the corresponding human legumain regions and should be excluded from the human vaccine. We can conclude that the regions of Sm32 that were recognized by antibodies of mice immunized with polymerizable peptides depended on the mice strain and on the hydrophilicity score of the peptides.
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Affiliation(s)
- N Chacón
- Sección de Biohelmintiasis, Instituto de Medicina Tropical, Universidad Central de Venezuela, Apartado Postal 47623, Zona Postal 1041-A, Los Chaguaramos, Caracas, Venezuela
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49
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Dalton JP, Brindley PJ, Knox DP, Brady CP, Hotez PJ, Donnelly S, O'Neill SM, Mulcahy G, Loukas A. Helminth vaccines: from mining genomic information for vaccine targets to systems used for protein expression. Int J Parasitol 2003; 33:621-40. [PMID: 12782060 DOI: 10.1016/s0020-7519(03)00057-2] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The control of helminth diseases of people and livestock continues to rely on the widespread use of anti-helminthic drugs. However, concerns with the appearance of drug resistant parasites and the presence of pesticide residues in food and the environment, has given further incentive to the goal of discovering molecular vaccines against these pathogens. The exponential rate at which gene and protein sequence information is accruing for many helminth parasites requires new methods for the assimilation and analysis of the data and for the identification of molecules capable of inducing immunological protection. Some promising vaccine candidates have been discovered, in particular cathepsin L proteases from Fasciola hepatica, aminopeptidases from Haemonchus contortus, and aspartic proteases from schistosomes and hookworms, all of which are secreted into the host tissues or into the parasite intestine where they play important roles in host-parasite interactions. Since secreted proteins, in general, are exposed to the immune system of the host they represent obvious candidates at which vaccines could be targeted. Therefore, in this article, we consider the potential values and uses of algorithms for characterising cDNAs amongst the collated helminth genomic information that encode secreted proteins, and methods for their selective isolation and cloning. We also review the variety of prokaryotic and eukaryotic cell expression systems that have been employed for the production and downstream purification of recombinant proteins in functionally active form, and provide an overview of the parameters that must be considered if these recombinant proteins are to be commercialised as vaccine therapeutics in humans and/or animals.
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Affiliation(s)
- John P Dalton
- School of Biotechnology, Dublin City University, Glasnevin, Dublin 9, Ireland.
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Mathieu MA, Bogyo M, Caffrey CR, Choe Y, Lee J, Chapman H, Sajid M, Craik CS, McKerrow JH. Substrate specificity of schistosome versus human legumain determined by P1-P3 peptide libraries. Mol Biochem Parasitol 2002; 121:99-105. [PMID: 11985866 DOI: 10.1016/s0166-6851(02)00026-9] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Asparaginyl endopeptidases, or 'legumains' have been identified and characterized in plants, the blood fluke parasite Schistosoma, and mammals. The legumains are a novel family of cysteine proteases and display restricted specificity for peptide hydrolysis on the carboxyl side of asparagine residues. Two forms of recombinant asparaginyl endopeptidase from Schistosoma mansoni (C197 Sm32 and N197C Sm32), expressed in Pichia pastoris, have been analyzed for substrate specificity using a positional-scanning synthetic combinatorial library (PS-SCL). We first screened Sm32 using a P1-diverse library. This library demonstrated the absolute specificity of Sm32 for asparagine at P1. To determine the P2-P3 preferences of Sm32, we constructed a library with asparagine fixed at P1, and the P2-P3 positions randomized. The library was screened using the two forms of Sm32, human asparaginyl endopeptidase, and to confirm its diversity, cruzain from Trypanosoma cruzi. The schistosome legumain showed a preference for P3: Thr>Ala>Val>Ile, and P2: Ala>Thr>Val>Asn, with an overall broader specificity at P3 than at P2. Both human and schistosome legumain can accommodate Thr and Ala at P2 and P3. However, optimal substrate sequences differ, with Sm32 preferring Thr-Ala-Asn, and human legumain preferring Pro-Thr-Asn. Predictions of substrate specificity from the library screen were confirmed using single peptide substrates for kinetic assays.
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Affiliation(s)
- Mary A Mathieu
- Department of Pathology, UCSF, San Francisco, CA 94143, USA.
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