Inhibition Of Papain Research Articles

Soluble Expression of Recombinant Human Cystatin C and Comparison of the Ni Column and Magnetic Bead Purification.

Cystatin C, also known as γ-trace or post-γ-globulin, is a cysteine protease inhibitor from the cystatin superfamily. It is usually used as a marker of the glomerular filtration rate owing to its low molecular weight and constant secretion. The recently available methods for cystatin C preparation have low outputs. Hence, a productive preparation system is urgently required. In this study, a 6 × His-tag coupled with a thrombin cleavage site was fused to the C-terminus of cystatin C, and the protein was well expressed in Escherichia coli after optimization. Then, two different systems were used to obtain no-tag cystatin C: a traditional nickel (Ni)-column system and a subtly Ni magnetic bead system. The column system was more commonly used, and the magnetic bead system was more convenient. Cystatin C (purity > 97%) was successfully obtained, and the yields in both the systems were higher than those in previous studies. Further, the proper folding status and bioactivity of recombinant cystatin C were confirmed using the papain inhibition assay, dynamic light scattering, and circular dichroism spectroscopy.

Efficient Site-Specific Antibody-Drug Conjugation by Engineering a Nature-Derived Recognition Tag for Microbial Transglutaminase.

Microbial transglutaminase (mTG) has recently emerged as a powerful tool for antibody engineering. In nature, it catalyzes the formation of amide bonds between glutamine side chains and primary amines. Being applied to numerous research fields from material sciences to medicine, mTG enables efficient site-specific conjugation of molecular architectures that possess suitable recognition motifs. In monoclonal antibodies, the lack of native transamidation sites is bypassed by incorporating specific peptide recognition sequences. Herein, we report a rapid and efficient mTG-catalyzed bioconjugation that relies on a novel recognition motif derived from its native substrate Streptomyces papain inhibitor (SPIP ). Improved reaction kinetics compared to commonly applied sequences were demonstrated for model peptides and for biotinylation of Her2-targeting antibody trastuzumab variants. Moreover, an antibody-drug conjugate assembled from trastuzumab that was C-terminally tagged with the novel recognition sequence revealed a higher payload-antibody ratio than the reference antibody.

Comparative Transcriptome Profiling of Gaeumannomyces graminis var. tritici in Wheat Roots in the Absence and Presence of Biocontrol Bacillus velezensis CC09.

This study aimed to explore potential biocontrol mechanisms involved in the interference of antagonistic bacteria with fungal pathogenicity in planta. To do this, we conducted a comparative transcriptomic analysis of the “take-all” pathogenic fungus Gaeumannomyces graminis var. tritici (Ggt) by examining Ggt-infected wheat roots in the presence or absence of the biocontrol agent Bacillus velezensis CC09 (Bv) compared with Ggt grown on potato dextrose agar (PDA) plates. A total of 4,134 differentially expressed genes (DEGs) were identified in Ggt-infected wheat roots, while 2,011 DEGs were detected in Bv+Ggt-infected roots, relative to the Ggt grown on PDA plates. Moreover, 31 DEGs were identified between wheat roots, respectively infected with Ggt and Bv+Ggt, consisting of 29 downregulated genes coding for potential Ggt pathogenicity factors – e.g., para-nitrobenzyl esterase, cutinase 1 and catalase-3, and two upregulated genes coding for tyrosinase and a hypothetical protein in the Bv+Ggt-infected roots when compared with the Ggt-infected roots. In particular, the expression of one gene, encoding the ABA3 involved in the production of Ggt’s hormone abscisic acid, was 4.11-fold lower in Ggt-infected roots with Bv than without Bv. This is the first experimental study to analyze the activity of Ggt transcriptomes in wheat roots exposed or not to a biocontrol bacterium. Our results therefore suggest the presence of Bv directly and/or indirectly impairs the pathogenicity of Ggt in wheat roots through complex regulatory mechanisms, such as hyphopodia formation, cell wall hydrolase, and expression of a papain inhibitor, among others, all which merit further investigation.

Giardiaintestinalis cystatin is a potent inhibitor of papain, parasite cysteine proteases and, to a lesser extent, human cathepsin B.

Cystatins are important regulators of papain-like cysteine proteases. In the protozoan parasite Giardiaintestinalis, papain-like cysteine proteases play an essential role in the parasite's biology and pathogenicity. Here, we characterized a cysteine protease inhibitor of G.intestinalis that belongs to type-I-cystatins. The parasite cystatin is shown to be a strong inhibitor of papain (Ki ≈0.3nm) and three parasite cysteine proteases (CP14019, CP16160 and CP16779, Ki ≈0.9-5.8nm), but a weaker inhibitor of human cathepsin B (Ki ≈79.9nm). The protein localizes mainly in the cytoplasm. Together, these data suggest that cystatin of G.intestinalis plays a role in the regulation of cysteine protease activities in the parasite and, possibly, in the interaction with the host.

Highly tunable thiosulfonates as a novel class of cysteine protease inhibitors with anti-parasitic activity against Schistosoma mansoni.

The development of a new class of cysteine protease inhibitors utilising the thiosulfonate moiety as an SH specific electrophile is described. This moiety has been introduced into suitable amino acid derived building blocks, which were incorporated into peptidic sequences leading to very potent i.e. sub micromolar inhibitors of the cysteine protease papain in the same range as the vinyl sulfone based inhibitor K11777. Therefore, their inhibitory effect on Schistosoma mansoni, a human blood parasite, that expresses several cysteine proteases, was evaluated. The homophenylalanine side chain containing compounds 27-30 and especially 36 showed promising activities compared with K11777 and warrant further investigations of these peptidic thiosulfonate inhibitors as new potential anti-parasitic compounds.

ClCPI, a cysteine protease inhibitor purified from Cassia leiandra seeds has antifungal activity against Candida tropicalis by inducing disruption of the cell surface.

Infections caused by Candida tropicalis have increased significantly worldwide in parallel with resistance to antifungal drugs. To overcome resistance novel drugs have to be discovered. The objective of this work was to purify and characterize a cysteine protease inhibitor from the seeds of the Amazon rainforest tree Cassia leiandra and test its inhibitory effect against C. tropicalis growth. The inhibitor, named ClCPI, was purified after ion exchange and affinity chromatography followed by ultrafiltration. ClCPI is composed of a single polypeptide chain and is not a glycoprotein. The molecular mass determined by SDS-PAGE in the absence or presence of β-mercaptoethanol and ESI-MS were 16.63 kDa and 18.362 kDa, respectively. ClCPI was stable in the pH range of 7.0-9.0 and thermostable up to 60 °C for 20 min. ClCPI inhibited cysteine proteases, but not trypsin, chymotrypsin neither alpha-amylase. Inhibition of papain was uncompetitive with a Ki of 4.1 × 10-7 M and IC50 of 8.5 × 10-7 M. ClCPI at 2.6 × 10-6 M reduced 50% C. tropicalis growth. ClCPI induced damages and morphological alterations in C. tropicalis cell surface, which led to death. These results suggest that ClCPI have great potential for the development of an antifungal drug against C. tropicalis.

DIFFERENCE BETWEEN ANTIMICROBIAL EFFECTS OF PAPACARIE AND PAPAIN ON STREPTOCOCCUS MUTANS IN VITRO

Objective: The aim is to compare the antimicrobial effects of papain and Papacarie with dilution and diffusion tests.Methods: There were two treatment groups and one Group control. The treatment group received papain and Papacarie, and the control groupreceived chlorhexidine, in five liquids with different concentrations of 0.5%, 0.25%, 0.125%, 0.0625%, and 0.03%. The dilution and diffusion testswere used to determine the minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and zone of inhibition for eachtreatment material.Results: MICs of papain and Papacarie were 12.5%, indicating that at a concentration of 12.5%, the material can inhibit the growth of Streptococcusmutans. Papain does not have an MBC value but the Papacarie has an MBC at 25%, which indicating that at a concentration of 25%, Papacarie hasbactericidal effects on S. mutans. The zone of inhibition of papain was lower than Papacarie.Conclusion: Based on chemomechanical caries removal materials, the antimicrobial effects of Papacarie were better than those of papain.

Purification and biochemical function of Astragalus membtanaceus pathogenesis-related protein 10

Astragalus membranaceus pathogenesis-related protein 10 (AmPR-10) is largely expressed in case of environmental pressure and pathogen invasion. This study aims to explore the biochemical functions of AmPR-10. The dried root of Astragalus membranaceus was mechanically homogenized and extracted by Tris-HCl buffer to obtain its crude extract, which was then purified by anion exchange chromatography and gel filtration chromatography to obtain electrophoretically pure AmPR-10. The nuclease activity of AmPR-10 was tested with different RNAs by detecting the absorption value at 260 nm. The results demonstrated potent nuclease activity toward yeast tRNA, yeast RNA, Poly (A) and Poly (C). The optimum reaction temperature was 50 °C and pH was 7-8. EDTA showed no effect on its activity, while Mg²⁺ exhibited potent activation effect on the activity, and Co²⁺, Ca²⁺ and Zn²⁺ manifested moderately inhibition of the activity. Since AmPR-10 had no sequence homology with other known nucleases, AmPR-10 was probably a novel nuclease. The inhibition kinetic data against papain was analyzed by Lineweaver-Burk plots, and the results showed that the inhibition of papain followed noncompetitive-type kinetics. AmPR-10 played an important role in Astragalus membranaceus defense mechanism against environmental pressure and pathogen invasion, which may be achieved by inhibiting cycteine enzymes activity.

Physico-chemical and in-silico analysis of a phytocystatin purified from Brassica juncea cultivar RoAgro 5444.

This study describes the isolation and purification of a phytocystatin from seeds of Brassica juncea (Indian mustard; cultivar RoAgro 5444), which is an important oilseed crop both agriculturally and economically. The protein was purified by gel filtration chromatography with 24.3% yield and 204-fold purification, and visualised by 2D gel electrophoresis. The 18.1 kDa mustard cystatin was highly specific for cysteine proteinases. The plant cystatin inhibited cathepsin B, confirming its role in conferring pest resistance. The inhibitor was highly stable over a pH range of 3-10 and retained significant inhibitory potential up to 70 °C. The stoichiometry of its interaction with papain, determined by isothermal calorimetry, suggests a 1:1 complex. Secondary structural elements calculated by far-UV circular dichroism (CD) spectroscopy show an 18.8% α-helical and 21% β-sheet structure. The protein was a non-competitive inhibitor of thiol proteinases. The Stokes radius and frictional co-efficient were used to describe the shape and size of the protein. Homology modelling and docking studies proposed a prototype illustrating the Brassica phytocystatin mediated papain inhibition. Molecular dynamics (MD) study revealed the excellent stability of the papain-phytocystatin complex during a simulation for 100 ns. Detailed results identify the mustard cystatin as an important member of the phytocystatin family.

Papain and its inhibitor E-64 reduce camelid semen viscosity without impairing sperm function and improve post-thaw motility rates

In camelids, the development of assisted reproductive technologies is impaired by the viscous nature of the semen. The protease papain has shown promise in reducing viscosity, although its effect on sperm integrity is unknown. The present study determined the optimal papain concentration and exposure time to reduce seminal plasma viscosity and investigated the effect of papain and its inhibitor E-64 on sperm function and cryopreservation in alpacas. Papain (0.1mg mL-1, 20min, 37°C) eliminated alpaca semen viscosity while maintaining sperm motility, viability, acrosome integrity and DNA integrity. Furthermore E-64 (10 µM at 37°C for 5min after 20min papain) inhibited the papain without impairing sperm function. Cryopreserved, papain-treated alpaca spermatozoa exhibited higher total motility rates after chilling and 0 and 1h after thawing compared with control (untreated) samples. Papain treatment, followed by inhibition of papain with E-64, is effective in reducing alpaca seminal plasma viscosity without impairing sperm integrity and improves post-thaw motility rates of cryopreserved alpaca spermatozoa. The use of the combination of papain and E-64 to eliminate the viscous component of camelid semen may aid the development of assisted reproductive technologies in camelids.

Partial purification of trypsin/papain inhibitors from Hymenaea courbaril L. seeds and antibacterial effect of protein fractions

ABSTRACT The crude extract and protein fractions of Hymenaea courbaril L. seeds were investigated for the presence of trypsin and papain inhibitors and antimicrobial activity against Vibrio parahaemolyticus, Staphylococcus aureus, and Escherichia coli. Protein fractions were obtained from the crude extract after precipitation with ammonium sulfate into three saturation ranges (0-30%, 30-60%, and 60-90%), called Hc030, Hc3060, and Hc6090, respectively. The crude extract and protein fractions inhibited trypsin and papain activity, but to different degrees. Antimicrobial activity was observed in Hc030 and Hc3060 fractions, but only against V. parahaemolyticus.The inhibitor isolated from the Hc3060 fraction was more effective in inhibiting trypsin (100% inhibition) than papain (54% inhibition), and showed an apparent molecular mass of 20 kDa. This study shows that H. courbaril seeds contain proteins with protease-inhibiting and antibacterial activity, indicating that this species is a source of bioactive compounds.

Natural cysteine protease inhibitors in protozoa: Fifteen years of the chagasin family.

Chagasin-type inhibitors comprise natural inhibitors of papain-like cysteine proteases that are distributed among Protist, Bacteria and Archaea. Chagasin was identified in the pathogenic protozoa Trypanosoma cruzi as an approximately 11kDa protein that is a tight-binding and highly thermostable inhibitor of papain, cysteine cathepsins and endogenous parasite cysteine proteases. It displays an Imunoglobulin-like fold with three exposed loops to one side of the molecule, where amino acid residues present in conserved motifs at the tips of each loop contact target proteases. Differently from cystatins, the loop 2 of chagasin enters the active-site cleft, making direct contact with the catalytic residues, while loops 4 and 6 embrace the enzyme from the sides. Orthologues of chagasin are named Inhibitors of Cysteine Peptidases (ICP), and share conserved overall tri-dimensional structure and mode of binding to proteases. ICPs are tentatively distributed in three families: in family I42 are grouped chagasin-type inhibitors that share conserved residues at the exposed loops; family I71 contains Plasmodium ICPs, which are large proteins having a chagasin-like domain at the C-terminus, with lower similarity to chagasin in the conserved motif at loop 2; family I81 contains Toxoplasma ICP. Recombinant ICPs tested so far can inactivate protozoa cathepsin-like proteases and their mammalian counterparts. Studies on their biological roles were carried out in a few species, mainly using transgenic protozoa, and the conclusions vary. However, in all cases, alterations in the levels of expression of chagasin/ICPs led to substantial changes in one or more steps of parasite biology, with higher incidence in influencing their interaction with the hosts. We will cover most of the findings on chagasin/ICP structural and functional properties and overview the current knowledge on their roles in protozoa.

Identification of Bidentate Salicylic Acid Inhibitors of PTP1B.

PTP1B is a master regulator in the insulin and leptin metabolic pathways. Hyper-activated PTP1B results in insulin resistance and is viewed as a key factor in the onset of type II diabetes and obesity. Moreover, inhibition of PTP1B expression in cancer cells dramatically inhibits cell growth in vitro and in vivo. Herein, we report the computationally guided optimization of a salicylic acid-based PTP1B inhibitor 6, identifying new and more potent bidentate PTP1B inhibitors, such as 20h, which exhibited a > 4-fold improvement in activity. In CHO-IR cells, 20f, 20h, and 20j suppressed PTP1B activity and restored insulin receptor phosphorylation levels. Notably, 20f, which displayed a 5-fold selectivity for PTP1B over the closely related PTPσ protein, showed no inhibition of PTP-LAR, PRL2 A/S, MKPX, or papain. Finally, 20i and 20j displayed nanomolar inhibition of PTPσ, representing interesting lead compounds for further investigation.

Some properties and possible biological role of peptidase inhibitors from the entomopathogenic fungus Tolypocladium cylindrosporum.

The activities of secreted and mycelial inhibitors of proteolytic enzymes from fungi of the order Hypocreales have been investigated. Inhibitors of bromelain, papain, and trypsin of low molecular mass (about 1kDa) and a subtilisin proteinaceous inhibitor with molecular mass of 45kDa were revealed in the culture liquid of the fungus Tolypocladium cylindrosporum. The subtilisin inhibitor from T. cylindrosporum has antibiotic properties, significantly decreased the activity of purified bacterial enzymes, and prevented the growth of the bacterium Pseudomonas sp. Data suggesting the existence in fungi of the Hypocreales order of two pools of peptidase inhibitors have been obtained.

Quantifying tetrahedral adduct formation and stabilization in the cysteine and the serine proteases

Two new papain inhibitors have been synthesized where the terminal α-carboxyl groups of Z-Phe-Ala-COOH and Ac-Phe-Gly-COOH have been replaced by a proton to give Z-Phe-Ala-H and Ac-Phe-Gly-H. We show that for papain, replacing the terminal carboxylate group of a peptide inhibitor with a hydrogen atom decreases binding 3–4 fold while replacing an aldehyde or glyoxal group with a hydrogen atom decreases binding by 300,000–1,000,000 fold. Thiohemiacetal formation by papain with aldehyde or glyoxal inhibitors is shown to be ~ 10,000 times more effective than hemiacetal or hemiketal formation with chymotrypsin. It is shown using effective molarities, that for papain, thiohemiacetal stabilization is more effective with aldehyde inhibitors than with glyoxal inhibitors. The effective molarity obtained when papain is inhibited by an aldehyde inhibitor is similar to the effective molarity obtained when chymotrypsin is inhibited by glyoxal inhibitors showing that both enzymes can stabilize tetrahedral adducts by similar amounts. Therefore the greater potency of aldehyde and glyoxal inhibitors with papain is not due to greater thiohemiacetal stabilization by papain compared to the hemiketal and hemiacetal stabilization by chymotrypsin, instead it reflects the greater intrinsic reactivity of the catalytic thiol group of papain compared to the catalytic hydroxyl group of chymotrypsin. It is argued that while the hemiacetals and thiohemiacetals formed with the serine and cysteine proteases respectively can mimic the catalytic tetrahedral intermediate they are also analogues of the productive and non-productive acyl intermediates that can be formed with the cysteine and serine proteases.

넙치(Paralichthys olivaceus) 알로부터 Serine Protease Inhibitors의 분획 특성

Protease inhibitors (PI) of trypsin and papain as target proteases from the roe of bastard halibut Paralichthys olivaceus were fractionated out using ammonium sulfate precipitation (A), DEAE 650M anion exchange chromatography (D), and Sephacryl S-300 gel filtration (S). The recovery percentages of the fractions with the strongest inhibitory activity for each fractionation method were 13% for the A4 fraction, 21.2% for the D3 fraction, and 21.3% for the S2 fraction, with specific inhibitory activities of the fractions toward trypsin and casein of 168, 139, and 218 U/mg, respectively, while no inhibition of papain was observed. The for the trypsin-specific substrate -benzoyl--arginine-p-nitroanilide (BAPNA) was 0.65, 1.55, 2.26, and 2.85 mg/mL for the A4, S2, A3, and D3 fractions, respectively. These results suggest that chromatographic fractionation methods (D and S) based on the molecular mass and charge of the protein were more effective at fractionating PI than was ammonium sulfate precipitation based on protein solubility, and that the bastard halibut roe extract acts as a serine protease inhibitor. Therefore, the PI fraction from fish roe might be useful for inhibiting proteases in foodstuffs, and could constitute an alternative food-grade inhibitor for the surimi industry.

Effect of wine inhibitors on the proteolytic activity of papain from Carica papaya L. latex.

The influence of potential inhibitors naturally present in wine on the proteolytic activity of papain from Carica papaya latex was investigated to evaluate its applicability in white wine protein haze stabilization. Enzymatic activity was tested against a synthetic tripeptide chromogenic substrate in wine-like acidic medium that consisted of tartaric buffer (pH 3.2) supplemented with ethanol, free sulfur dioxide (SO2 ), grape skin and seed tannins within the average ranges of concentrations that are typical in wine. The diagnosis of inhibition type, performed with the graphical method, demonstrated that all of tested wine constituents were reversible inhibitors of papain. The strongest inhibition was exerted by free SO2 , which acted as a mixed-type inhibitor, similar to grape skin and seed tannins. Finally, when tested in table white wines, the catalytic activity of papain, even when if it was ascribable to the hyperbolic behavior of Michaelis-Menten equation, was determined to be strongly affected by free SO2 and total phenol level.

Isolation and purification of a papain inhibitor from Egyptian genotypes of barley seeds and its in vitro and in vivo effects on the cowpea bruchid, Callosobruchus maculatus (F.)

The cysteine inhibitors that are known as cystatin have been identified and characterized from several plant species. In the current study, 44 barley (Hordeum vulgare) genotypes including 3 varieties and 41 promising lines were screened for their potential as protease inhibitors. The barley genotypes showed low inhibitory activity against trypsin and chymotrypsin enzymes with a mean of 4.15 TIU/mg protein and 4.40 CIU/mg protein. The barley variety, Giza 123, showed strong papain inhibitory activity of 97.09 PIU/mg proteins and was subjected for further purification studies using ammonium sulfate fractionation and DEAE-Sephadex A-25 column. Barley purified proteins showed two bands on SDS-PAGE corresponding to a molecular mass of 12.4-54.8 kDa. The purified barley PI was found to be stable at a temperature below 80 °C and at a wide range of pH from 2 to 12. Barley PI was found to have higher potential inhibitory activity against papain enzyme compared to the standard papain inhibitor, E-64 with an IC50 value of 21.04 µg/ml and 25.62 µg/ml for barley PI and E-64, respectively. The kinetic analysis revealed a non-competitive type of inhibition with a Ki value of 1.95 × 10(-3 )µM. The antimetabolic effect of barley PI was evaluated against C. maculatus by incorporating the F30-60 protein of the purified inhibitor into the artificial diet using artificial seeds. Barley PI significantly prolonged the development of C. maculatus in proportion to PI concentration. Barley PI significantly increased the mortality of C. maculatus and caused a significant reduction in its fecundity. On the other hand, barley PI seemed to have non-significant effects on the adult longevity and the adult dry weight. The in vitro and in vivo results proved the efficiency of the papain inhibitory protein isolated from barley as a tool for managing the cowpea bruchid, C. maculatus.

Influence of azide incorporation on binding affinity by small papain inhibitors

In order to develop affinity-based biosensor platforms, appropriate ligands with a functional handle for immobilization onto a biosensor surface are required. To this end, a library of papain inhibitors was designed and synthesized, containing different azide linkers for subsequent immobilization by 'click' chemistry, in this particular case by copper-free, strain-promoted azide-alkyne cycloaddition (SPAAC). Furthermore, a molecular docking study was performed to obtain a better insight as to at which position such azide handles could be tolerated without affecting binding affinity. Although the azide moiety is small, in some cases its introduction strongly influenced the binding affinity. For one class of inhibitors a swapped binding mode was proposed to explain the results. In addition, a specific site for linker introduction was identified, which did not significantly affect the binding affinity.

A fragment-based method to discover irreversible covalent inhibitors of cysteine proteases.

A novel fragment-based drug discovery approach is reported which irreversibly tethers drug-like fragments to catalytic cysteines. We attached an electrophile to 100 fragments without significant alterations in the reactivity of the electrophile. A mass spectrometry assay discovered three nonpeptidic inhibitors of the cysteine protease papain. The identified compounds display the characteristics of irreversible inhibitors. The irreversible tethering system also displays specificity: the three identified papain inhibitors did not covalently react with UbcH7, USP08, or GST-tagged human rhinovirus 3C protease.