Cysteine protease inhibitors alter Golgi complex ultrastructure and function in Trypanosoma cruzi

1998 ◽  
Vol 111 (5) ◽  
pp. 597-606 ◽  
Author(s):  
J.C. Engel ◽  
P.S. Doyle ◽  
J. Palmer ◽  
I. Hsieh ◽  
D.F. Bainton ◽  
...  
Keyword(s):  
Trypanosoma Cruzi ◽  
Protease Inhibitor ◽  
Protease Inhibitors ◽  
Golgi Complex ◽  
Cysteine Protease ◽  
Intracellular Localization ◽  
Fluorescent Microscopy ◽  
Brefeldin A ◽  
Cysteine Protease Inhibitor ◽  
Cysteine Protease Inhibitors

Cruzain, the major cysteine protease of the protozoan parasite Trypanosoma cruzi, is a target of rational drug design for chemotherapy of Chagas' disease. The precise biological role of cruzain in the parasite life cycle and the mechanism involved in the trypanocidal effect of cysteine protease inhibitors are still unclear. Here we report biological and ultrastructural alterations caused by cysteine protease inhibitors in T. cruzi epimastigotes. Cruzain, a glycoprotein that transits the Golgi-endosomal pathway, localized to pre-lysosomes/lysosomes in the posterior end of untreated epimastigotes by fluorescent microscopy utilizing either a biotinylated cysteine protease inhibitor to tag the active site, or a specific anti-cruzain antibody. Radiolabeled or biotinylated cysteine protease inhibitors bound exclusively to cruzain in intact epimastigotes confirming that cruzain is accessible to, and is targeted by the inhibitors. Treatment of T. cruzi epimastigotes with specific cysteine protease inhibitors arrested growth, altered the intracellular localization of cruzain, and induced major alterations in the Golgi complex. Following treatment, cruzain accumulated in peripheral dilations of Golgi cisternae. There was a concomitant 70% reduction in gold-labeled cruzain transported to lysosomes. Cisternae abnormalities in the Golgi compartment were followed by distention of ER and nuclear membranes. Brefeldin A increased the number and size of cisternae in epimastigotes. Pre-treatment of epimastigotes with cysteine protease inhibitors followed by exposure to brefeldin A induced a more rapid appearance of the cysteine protease inhibitor-induced Golgi alterations. Our results suggest that cysteine protease inhibitors prevent the normal autocatalytic processing and trafficking of cruzain within the Golgi apparatus. Accumulation of cruzain may decrease mobility of Golgi membranes and result in peripheral distention of cisternae. These major alterations of the Golgi complex parallel the death of T. cruzi epimastigotes.

scholarly journals A Phytophthora palmivora Extracellular Cystatin-Like Protease Inhibitor Targets Papain to Contribute to Virulence on Papaya

2018 ◽  
Vol 31 (3) ◽  
pp. 363-373 ◽  
Author(s):  
Rebecca Gumtow ◽  
Dongliang Wu ◽  
Janice Uchida ◽  
Miaoying Tian
Keyword(s):  
Protease Inhibitor ◽  
Protease Inhibitors ◽  
Cysteine Protease ◽  
Gene Editing ◽  
Sequence Data ◽  
Cysteine Protease Inhibitor ◽  
Phytophthora Palmivora ◽  
Cysteine Protease Inhibitors ◽  
Successful Infection

Papaya fruits, stems, and leaves are rich in papain, a cysteine protease that has been shown to mediate plant defense against pathogens and insects. Yet the oomycete Phytophthora palmivora is a destructive pathogen that infects all parts of papaya plants, suggesting that it has evolved cysteine protease inhibitors to inhibit papain to enable successful infection. Out of five putative extracellular cystatin-like cysteine protease inhibitors (PpalEPICs) from P. palmivora transcriptomic sequence data, PpalEPIC8 appeared to be unique to P. palmivora and was highly induced during infection of papaya. Purified recombinant PpalEPIC8 strongly inhibited papain enzyme activity, suggesting that it is a functional cysteine protease inhibitor. Homozygous PpalEPIC8 mutants were generated using CRISPR/Cas9-mediated gene editing via Agrobacterium-mediated transformation (AMT). Increased papain sensitivity of in-vitro growth and reduced pathogenicity during infection of papaya fruits were observed for the mutants compared with the wild-type strain, suggesting that PpalEPIC8, indeed, plays a role in P. palmivora virulence by inhibiting papain. This study provided genetic evidence demonstrating that plant-pathogenic oomycetes secrete cystatins as important weapons to invade plants. It also established an effective gene-editing system for P. palmivora by the combined use of CRISPR/Cas9 and AMT, which is expected to be applicable to other oomycetes.

scholarly journals Cysteine Protease Inhibitors Cure an Experimental Trypanosoma cruzi Infection

1998 ◽  
Vol 188 (4) ◽  
pp. 725-734 ◽  
Author(s):  
Juan C. Engel ◽  
Patricia S. Doyle ◽  
Ivy Hsieh ◽  
James H. McKerrow
Keyword(s):  
Trypanosoma Cruzi ◽  
Protease Inhibitors ◽  
Chagas Disease ◽  
Golgi Complex ◽  
Cysteine Protease ◽  
Parasitic Infection ◽  
Host Cells ◽  
Vinyl Sulfone ◽  
Cysteine Protease Inhibitors ◽  
Lethal Infection

Trypanosoma cruzi is the causative agent of Chagas' disease. The major protease, cruzain, is a target for the development of new chemotherapy. We report the first successful treatment of an animal model of Chagas' disease with inhibitors designed to inactivate cruzain. Treatment with fluoromethyl ketone–derivatized pseudopeptides rescued mice from lethal infection. The optimal pseudopeptide scaffold was phenylalanine-homophenylalanine. To achieve cure of infection, this pseudopeptide scaffold was incorporated in a less toxic vinyl sulfone derivative. N-methyl piperazine-Phe-homoPhe-vinyl sulfone phenyl also rescued mice from a lethal infection. Six of the treated mice survived over nine months, three without further treatment. Three mice that had entered the chronic stage of infection were retreated with a 20-d regimen. At the conclusion of the experiments, five of the six mice had repeated negative hemacultures, indicative of parasitological cure. Studies of the effect of inhibitors on the intracellular amastigote form suggest that the life cycle is interrupted because of inhibitor arrest of normal autoproteolytic cruzain processing at the level of the Golgi complex. Parasites recovered from the hearts of treated mice showed the same abnormalities as those treated in vitro. No abnormalities were noted in the Golgi complex of host cells. This study provides proof of concept that cysteine protease inhibitors can be given at therapeutic doses to animals to selectively arrest a parasitic infection.

Upregulation of the secretory pathway in cysteine protease inhibitor-resistant Trypanosoma cruzi

2000 ◽  
Vol 113 (8) ◽  
pp. 1345-1354
Author(s):  
J.C. Engel ◽  
C.T. Garcia ◽  
I. Hsieh ◽  
P.S. Doyle ◽  
J.H. McKerrow
Keyword(s):  
Trypanosoma Cruzi ◽  
Protease Inhibitor ◽  
Golgi Complex ◽  
Cysteine Protease ◽  
Secretory Pathway ◽  
Complex Function ◽  
Cysteine Protease Inhibitor ◽  
Cross Resistance ◽  
Structural Levels

A novel chemotherapy in development for Chagas' disease targets cruzain, the major cysteine protease of Trypanosoma cruzi. Peptidomimetic inhibitors disrupt the intracellular cycle of the parasite and rescue animals from a lethal infection. Inhibitor killing of parasites results from interruption of autocatalytic cruzain processing and transport to lysosomes, and massive accumulation of precursor protein in the Golgi complex. To further understand the mechanisms of protease processing and transport in this primitive eukaryote, and uncover potential mechanisms for resistance to these drugs, we generated cysteine-protease inhibitor (CPI)-resistant epimastigotes in vitro and investigated the mechanisms involved at the biochemical and structural levels. Resistance to 20-fold the lethal CPI concentration, achieved after a year of gradual drug increase, was accompanied by a modest decrease in growth rate. A marked increase in the number of vesicles trafficking from the Golgi complex to the flagellar pocket occurs in resistant cells. No mature protease reaches lysosomes though accumulation of endocytosed gold particles in lysosomes appears to be normal. Higher molecular mass cruzain species, consistent with complexes of cruzain precursors and inhibitor, are secreted by CPI-resistant parasites into the culture supernatant. Release of these cruzain precursors may be facilitated by an enhanced acidification of trans-Golgi cisternae in resistant parasites. The pH within Golgi cisternae is higher in control epimastigotes and most mature cruzain is lysosomal. Cruzain activity is negligible in CPI-resistant epimastigote extracts compared to the parental clone. Activity is restored following withdrawal of the inhibitor. No cross-resistance to the therapeutic drugs nifurtimox and benznidazole occurred and, conversely, parasites resistant to these drugs were sensitive to CPI. Protease inhibitors are thus potential therapeutical alternatives in cases of nifurtimox/benznidazole resistance. Cumulatively, these results suggest that CPI-resistance induces upregulation of Golgi complex function and post-Golgi secretory pathway, and release of precursors before the enzyme reaches its site of biologic activity.

scholarly journals Studies of Inhibitory Mechanisms of Propeptide-Like Cysteine Protease Inhibitors

2014 ◽  
Vol 2014 ◽  
pp. 1-10 ◽  
Author(s):  
Bui T. T. Nga ◽  
Yuki Takeshita ◽  
Misa Yamamoto ◽  
Yoshimi Yamamoto
Keyword(s):  
Protease Inhibitors ◽  
Cysteine Protease ◽  
Cathepsin L ◽  
Cysteine Residue ◽  
Cysteine Protease Inhibitor ◽  
Inhibition Mechanism ◽  
Cysteine Protease Inhibitors ◽  
Inhibitory Potency ◽  
Inhibitory Mechanisms

Mouse cytotoxic T-lymphocyte antigen-2α (CTLA-2α), Drosophila CTLA-2-like protein (crammer), and Bombyx cysteine protease inhibitor (BCPI) belong to a novel family of cysteine protease inhibitors (I29). Their inhibitory mechanisms were studied comparatively. CTLA-2α contains a cysteine residue (C75), which is essential for its inhibitory potency. The CTLA-2α monomer was converted to a disulfide-bonded dimer in vitro and in vivo. The dimer was fully inhibitory, but the monomer, which possessed a free thiol residue, was not. A disulfide-bonded CTLA-2α/cathepsin L complex was isolated, and a cathepsin L subunit with a molecular weight of 24,000 was identified as the interactive enzyme protein. Crammer also contains a cysteine residue (C72). Both dimeric and monomeric forms of crammer were inhibitory. A crammer mutant with Cys72 to alanine (C72A) was fully inhibitory, while the replacement of Gly73 with alanine (G73A) caused a significant loss in inhibitory potency, which suggests a different inhibition mechanism from CTLA-2α. BCPI does not contain cysteine residue. C-terminal region (L77-R80) of BCPI was essential for its inhibitory potency. CTLA-2α was inhibitory in the acidic pH condition but stabilized cathepsin L under neutral pH conditions. The different inhibition mechanisms and functional considerations of these inhibitors are discussed.

scholarly journals The complex world of plant protease inhibitors: Insights into a Kunitz-type cysteine protease inhibitor of Arabidopsis thaliana

2017 ◽  
Vol 11 (1) ◽  
pp. e1368599 ◽  
Author(s):  
Sachin Rustgi ◽  
Edouard Boex-Fontvieille ◽  
Christiane Reinbothe ◽  
Diter von Wettstein ◽  
Steffen Reinbothe
Keyword(s):  
Arabidopsis Thaliana ◽  
Protease Inhibitor ◽  
Protease Inhibitors ◽  
Cysteine Protease ◽  
Cysteine Protease Inhibitor ◽  
Complex World ◽  
Plant Protease ◽  
Kunitz Type

Synthesis of quinoline derivatives as potential cysteine protease inhibitors

2020 ◽  
Author(s):  
Marina MS Andrade ◽  
Luan C Martins ◽  
Gabriel VL Marques ◽  
Carla A Silva ◽  
Gilson Faria ◽  
...  
Keyword(s):  
Trypanosoma Cruzi ◽  
Protease Inhibitors ◽  
Cysteine Protease ◽  
Inhibitory Activity ◽  
Molecular Targets ◽  
Cysteine Proteases ◽  
Leishmania Species ◽  
Molecular Target ◽  
Quinoline Derivatives ◽  
Cysteine Protease Inhibitors

Aim: Cysteine proteases are important molecular targets involved in the replication, virulence and survival of parasitic organisms, including Trypanosoma and Leishmania species. Methodology & results: Analogs of the 7-chloro- N-[3-(morpholin-4-yl)propyl]quinolin-4-amine were synthesized and their inhibitory activity against the enzymes cruzain and rhodesain as well as against promastigotes forms of Leishmania species and epimastigotes forms of Trypanosoma cruzi were evaluated. Five compounds showed activity against both enzymes with IC50 values ranging from 23 to 123 μM. Among these, compounds 3 and 4 displayed leishmanicidal activity; compound 4 was the most promising with IC50 values <10 μM and no cytotoxicity for uninfected cells. Conclusion: The results obtained indicate that cysteine proteases are likely to be the molecular target of compounds 3 and 4.

scholarly journals Tigutcystatin, a cysteine protease inhibitor from Triatoma infestans midgut expressed in response to Trypanosoma cruzi

2011 ◽  
Vol 413 (2) ◽  
pp. 241-247 ◽  
Author(s):  
Diego S. Buarque ◽  
Letícia M.N. Spindola ◽  
Rafael M. Martins ◽  
Glória R.C. Braz ◽  
Aparecida S. Tanaka
Keyword(s):  
Trypanosoma Cruzi ◽  
Protease Inhibitor ◽  
Cysteine Protease ◽  
Cysteine Protease Inhibitor ◽  
Triatoma Infestans

Crystal structure of chagasin, the endogenous cysteine-protease inhibitor from Trypanosoma cruzi

2007 ◽  
Vol 157 (2) ◽  
pp. 416-423 ◽  
Author(s):  
Aline Almeida Figueiredo da Silva ◽  
Leandro de Carvalho Vieira ◽  
Marco Aurélio Krieger ◽  
Samuel Goldenberg ◽  
Nilson Ivo Tonin Zanchin ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Trypanosoma Cruzi ◽  
Protease Inhibitor ◽  
Cysteine Protease ◽  
Cysteine Protease Inhibitor
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