Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “PAPAIN”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 451 records · Page 25Linked to original sources
PubMed1986

Papain-induced changes in the guinea pig knee joint with special reference to cartilage healing.

The repair of articular cartilage following papain injection into the knee joint of the guinea pig was studied by light and electron microscopy, as well as by autoradiography using tritiated thymidine. Papain injection rapidly produced complete degradation of cartilage proteoglycan. Although a number of chondrocytes were also destroyed, the remaining chondrocytes showed mitotic cell division with resultant formation of cell clusters. Such chondrocytic regeneration, however, did not contribute significantly to the repair of cartilage tissue. On the other hand, mesenchymal cells proliferated from the transition zone and extended over the surface of the damaged cartilage. At the peripheral portion of the articular surface, they migrated and differentiated into chondrocytes with the formation of abundant intercellular matrix to produce hyaline cartilage. From these findings, it was apparent that mesenchymal cells in the transition zone were actively engaged in the repair of articular cartilage.

Animals↗
PubMed2001

Mixture of trypsin, chymotrypsin and papain reduces formation of metastases and extends survival time of C57Bl6 mice with syngeneic melanoma B16.

PURPOSE: The aim of the present study was to investigate the effect of a mixture of proteolytic enzymes (comprising trypsin, chymotrypsin and papain) on the metastatic model of syngeneic melanoma B16. METHODS: 140 C57B16 mice were divided into two control and two "treated" groups. Control groups received saline rectally, twice a day starting 24 h after intracutaneous transplantation (C1) or from the time point of the primary B16 melanoma extirpation (C2), respectively. "Treated" groups were rectally administered a mixture of 0.2 mg trypsin, 0.5 mg papain, and 0.2 mg chymotrypsin twice daily starting 24 h after transplantation (E1) or after extirpation of the tumor (E2), respectively. Survival of mice and B16 melanoma generalization were observed for a period of 100 days. Immunological evaluation of B16 melanoma cells in the ascites was accomplished. CD44, CD54 and CD106 cells were measured by flow cytometry. RESULTS: Administration of proteolytic enzymes to mice inhibited the growth of primary tumors, and tumor recurrences were less numerous. Importantly, metastasis was considerably curtailed both in the vicinity of the primary tumor and at distant locales. These findings correlated with a decreased expression of CD44 and CD54 molecules in tumors exposed to proteolytic enzymes in vivo. CONCLUSIONS: Our data suggest that serine and cysteine proteinases suppress B16 melanoma, and restrict its metastatic dissemination in C57B16 mice.

Administration, Rectal↗
PubMed1982

Selective inhibition of condylar growth in the rabbit mandible using intra-articular papain.

The purpose of this study was to clarify the relative importance of the condyle in mandibular growth. Activated papain, a protease which inhibits endochondral growth, was injected for 4 weeks into the left temporomandibular joints of growing rabbits. Histologic and morphologic changes were evaluated microscopically and by measurement of dried skulls and serial cephalometric radiographs. The injected condyles showed a rapid but temporary depletion of the cartilage matrix. Repeated injections produced severe arthritic changes in some cases. The papain caused a significant decrease in vertical ramal growth. Mandibular length was unaffected. The unilateral injections also produced vertical asymmetry characterized by a canting of the mandibular plane superiorly toward the injected side. It was concluded that, in the rabbit, condylar growth is essential for normal vertical growth of the ramus but has little influence on the length of the mandible.

Animals↗
PubMed1983

Interaction of alpha 2-macroglobulin with trypsin, chymotrypsin, plasmin, and papain.

The interaction alpha 2-macroglobulin with four proteinases has been investigated by binding assays and by gel electrophoresis. At pH 7.65 the binding ratios of the proteinase-alpha 2-macroglobulin complexes were found to be 2:1 (trypsin and papain), 1.4:1 (chymotrypsin), and 1:1 (plasmin). The progressive decrease in the stoichiometry of the three seryl proteinase complexes was paralleled by a concomitant decrease in the proteinase-dependent specific cleavage of the alpha 2-macroglobulin peptide chains. Rate studies have shown that the relative rates of reaction of the proteinases with alpha 2-macroglobulin also varied greatly: papain greater than trypsin greater than chymotrypsin greater than plasmin. The data suggest that the ability of a proteinase to saturate the second proteinase binding site is a reflection of its ability to bind to alpha 2-macroglobulin and cleave the second pair of scissile alpha 2-macroglobulin peptide bonds before the alpha 2-macroglobulin has undergone the conformational change initiated by the formation of the 1:1 proteinase alpha 2-macroglobulin complex.

Chymotrypsin↗
PubMed1975

On the reaction of papain and succinylpapin with diazo-1-H-tetrazole.

1. The reaction of papain and succinylpapain with diazo-1-H-tetrazole was investigated under different conditions. The extent of modification of the amino acids histidine, tyrosine, tryptophan and lysine was determined spectrophotometrically and/or by amino acid analysis. 2. Only one of the two histidine residues present in the enzyme reacts with diazo-1-H-tetrazole forming a monoazo derivative. The pH dependence of the coupling reaction reveals a normal pK of this reactive histidine. There are several arguments suggesting that this may be histidine 159 near the essential SH-group of papain. 3. All five tryptophan residues of the protein react with the diazonium ion below pH 7 forming a monoazo derivative with an absorption maximum at 370 nm, above pH 7 only four residues couple with diazo-1-H-tetrazole. The reaction of one tryptophan and one histidine are correlated as can be concluded from the pH dependence of the coupling rate of both amino acids and the parallel impairment of the catalytic acitivity. 4. 10-11 tyrosine residues out of 19 react with diazo-1-H-tetrazole to give bisazo compounds. 5 residues involved in hydrogen bridges form monoazo compounds. Only 12 tyrosines can be acylated by acetylimidazole. A relationship between the extent of modification of tyrosine and the activity of the enzyme could not be found.

Amino Acids↗
PubMed1978

The differential enzyme susceptibility of bovine immunoglobulin G1 and immunoglobulin G2 to pepsin and papain.

Purified bovine immunoglobulins IgG1 and IgG2 were subjected to enzymatic degradation with pepsin and papain. Results were monitored using density gradient ultracentrifugation, acrylamide electrophosesis and immunodiffusion employing subclass- and light chain-specific antisera. The results indicated a marked enzymatic susceptibility of IgG1 to digestion with pepsin. This differential susceptibility can also be demonstrated in unfractionated bovine gamma-globulin. No striking differences between the two subclasses were observed during treatment with papain in the presence of cysteine and after 24 h, most IgG1 and IgG2 was degraded to Fc and Fab fragments. The pepsin Fc fragment generated from IgG2 was larger than that generated from IgG1 although the F(ab')2 fragments were simialr in size. These results are consistent with the hypothesis that the Fc region of IgG1 contains multiple cleavage sites for pepsin whereas IgG2 has few. Rabbits immunized with the first elution peak from a 30 h pepsin digest of bovine gamma-globulin fractionated on Sephadex G-150, responded primarily to common gamma-chain and IgG2-specific determinants. Thus, the differential susceptibility of bovine subclasses to pepsin provides a method for stimulating IgG2-specific antibodies in rabbits.

Animals↗
PubMed1981

Structure of tetanus toxin: the arrangement of papain digestion products within the heavy chain-light chain framework of extracellular toxin.

Upon digestion with papain, single chain intracellular tetanus toxin was completely converted to the extracellular form of the toxin, which consists of two disulfide-linked polypeptide chains (heavy chain and light chain of tetanus toxin). A portion of the material was degraded further by papain to yield the two major protein fragments, B and C, respectively, previously identified after digesting extracellular tetanus toxin with this enzyme. Thus it may be concluded that the order of release of these of these fragments from the intracellular toxin does not provide a clue as to their position within the original molecule. However, N-terminal analysis of the two fragments in conjunction with recent N-terminal data on tetanus toxin itself clearly indicated that fragment B of tetanus toxin contains the light chain polypeptide and the N-terminal portion of the heavy chain, whereas fragment C is derived from the C-terminal portion of the heavy chain.

Clostridium tetani↗
PubMed1990

A comparison between the binding modes of a substrate and inhibitor to papain as observed in complex crystal structures.

On the basis of the crystal structures of papain complexed with the substrate analogue benzyloxycarbonyl-L-phenylalanyl-L-alanine chloromethyl-ketone (Drenth, J., Kalk, K.H., and Swen, H.M. (1976) Biochemistry 15, 3731-3738) and with the inhibitor E-64-c, the binding modes were compared at the atomic level to clarify the functional difference between the substrate and inhibitor. Irrespective of the reverse chemical bonding in the peptide bonds, both the molecules are located at the S subsites of papain with similar interactions. However, the inhibitory activity of E-64-c is characterized by the stereochemical function of a carboxyoxirane ring and the tight binding of the isopentylaminoleucyl side chain to the S subsites.

Amino Acid Chloromethyl Ketones↗
PubMed1985

A new function of kininogens as thiol-proteinase inhibitors: inhibition of papain and cathepsins B, H and L by bovine, rat and human plasma kininogens.

The amidolytic activities of papain and rat liver cathepsins B, H and L were strongly inhibited by high (HMM) and low (LMM) molecular mass kininogens from bovine, human and rat plasmas, and their Ki values were estimated to be in the order of 10(-10) - 10(-11)M for papain and 10(-8) - 10(-9)M for cathepsins. The derivatives of bovine kininogens, HMM kinin-free protein, HMM kinin- and fragment 1 X 2-free protein, and LMM kinin-free protein also showed strong inhibitory activity toward these thiol-proteinases. These results suggest that a reactive site which interacts with thiol-proteinases is contained in the heavy chain portion in kininogens.

Animals↗
PubMed1985

Papain digestion of the subunits of (Na,K)-ATPase.

Membrane-bound (Na,K)-ATPases were exposed to limited papain digestion. We could not find the active (Na,K)-ATPase lacking glycoprotein subunit for the enzymes from three different sources (outer medulla of dog kidney, electric organs of Narke japonica and larvae of Artemia salina). It seemed unlikely that the glycoprotein subunit was selectively removed from (Na,K)-ATPase by papain digestion.

Animals↗
PubMed1987

Proteolysis rates of a myosin heavy chain site with papain. Evidence for a combined LC2-filament-mediated mechanism.

In striated muscle myosin, a proteolysis site at the 25-50 kDa junction, susceptible in the filament and efficiently protected by nucleotides, is similarly protected when myosin is monomeric. Kinetic studies at low ionic strength show a close relationship between LC2 cleavage or degradation rate and cleavage of the 25-50 kDa heavy chain site. The myosin-[(T)-LC2'] species forms normal reconstituted filaments but its 25-50 kDa site susceptibility is closer to that of monomeric myosin, thus becoming practically ionic strength-independent. In this species the absence of the LC2 N-terminal segment induces a significantly greater susceptibility of the papain-sensitive site in LC1. In an LC2-depleted myosin the 25-50 kDa site susceptibility also becomes ionic strength-independent, however, the cleavage rates are then closer to that of filaments. Susceptibility in HMM and S1 is also much less dependent on ionic strength with rates intermediary between those of filament and monomer. These observations show that the maximum susceptibility to papain of the 25-50 kDa site requires both the integrity of the LC2 light chain and the filament structure and furthermore provide evidence that: (i) the LC2 N-terminus interacts specifically with some part of the filament; (ii) this interaction induces a specific transconformation in a region close to the ATPase active site; (iii) there is an interrelationship between LC1 and LC2 light chain N-terminal extremities, at least in the filament structure.

Animals↗
PubMed1991

Primary structure of bovine cathepsin S. Comparison to cathepsins L, H, B and papain.

The primary structure of bovine cathepsin S was determined by combining results of protein and peptide sequencing with the sequence deduced from nucleic acid sequencing. Using polymerase chain reaction (PCR) technology, cDNA clones commencing at amino acid 22 of the mature enzyme and continuing through the 3' untranslated region of bovine cathepsin S mRNA were isolated and sequenced. The open reading frame in these overlapping clones correctly predicts the determined amino acid sequence of 13 tryptic peptides derived from purified bovine spleen cathepsin S. The deduced amino acid sequence shows that mature bovine cathepsin S consists of 217 amino acids corresponding to a molecular weight of 23.7 kDa. Cathepsin S belongs to the papain superfamily of lysosomal cysteine proteinases and shares 41% identity with papain. Amino acid sequence identities of bovine cathepsin S to human cathepsins L, H, and B are 56%, 47% and 31% respectively.

Amino Acid Sequence↗
PubMed1991

Nature of papain products resulting from inactivation by a peptidyl O-acyl hydroxamate.

Mass spectrometry has been used to provide insights into the mechanism of inhibition of cysteine proteases by a hydroxylamine derivative, CBZ-Phe-Gly-NH-O-CO-(2,4,6-Me3)Ph. An oxidized form of papain resulting from the incubation of the enzyme with the peptidyl hydroxamate in the absence of a reducing agent has been identified as a sulfinic acid. The presence of a covalent enzyme-inhibitor complex of molecular mass consistent with a sulfenamide adduct of papain could also be detected by this method. Implications on the mechanism of inactivation of cysteine proteases by peptidyl hydroxamates are discussed.

Dithiothreitol↗
PubMed1992

Glucose binding enhances the papain susceptibility of the intracellular loop of the GLUT1 glucose transporter.

Digestion of human GLUT1 protein in erythrocytes with 5 micrograms/ml papain for 5 min yielded several fragments. By using several site-specific antibodies, two of these fragments containing the intracellular loop domain between M6 and M7 were demonstrated to be further digested by a prolonged incubation with papain. The addition of 0.2 M D-glucose enhanced this digestion between M6 and M7 by approximately 3.5-fold, while the addition of 0.2 M D-sorbitol exhibited no effects. These results strongly suggest that D-glucose binding induces the conformational change of the intracellular loop domain between M6 and M7 of GLUT1 protein. Since the homology of the amino acid sequence was low in this intracellular domain among the five facilitative glucose transporter isoforms, this intracellular loop might contribute to the difference in their Km and Vmax values for glucose uptake.

Erythrocyte Membrane↗
PubMed1992

New intramolecularly quenched fluorogenic peptide substrates for the study of the kinetic specificity of papain.

A series of new substrates for determining the catalytic activity of cysteine proteinases is described. The rate of hydrolysis by papain was monitored by a fluorescence continuous assay based on internal resonance energy transfer using 5-[(2-aminoethyl)amino]naphtalene-1-sulfonic acid (EDANS) and 4-(4-dimethylaminophenylazo)benzoic acid (DABCYL) as fluorescent donor and quenching acceptor, respectively, in peptides with the general structure: DABCYL-Lys-Phe-Gly-Xxx-Ala-Ala-EDANS. The substrates were used to evaluate the effect of amino acid structure in the S1' position on the kinetic parameters for papain catalyzed hydrolysis.

Amino Acid Sequence↗
PubMed1989

The active site of papain. All-atom study of interactions with protein matrix and solvent.

The proton transfer between the Cys25 and His159 residues in the active centre of the proteolytic enzyme papain is investigated with the Hartree-Fock SCF direct reaction field method. The active centre is treated quantum mechanically, while the environment is represented by interacting partial charges and polarizabilities. All protein atoms around the active site are included explicitly in the calculations. In this way a complete description is given of both the electrostatic and the dielectric properties of the enzyme. The protein matrix stabilizes the zwitterionic form of Cys-His, which is thought to be the catalytically active state much more than the neutral configuration. The most important contribution to the stabilization comes from the alpha-helix to which Cys25 is attached; more than half of its effect is due to the backbone atoms of Cys25 itself. Other important factors are the Asn175 side-chain and the solvent. Solvent effects are estimated by means of Monte Carlo calculations of crystal water molecules that are located near the active site. The total energies of the neutral and zwitterionic structures are similar, confirming the idea that a zwitterion can exist in the active centre of papain. The energy difference, however, is sensitive to the geometry of the active site, suggesting that the two structures are in thermal equilibrium. Classical analogues of the quantum mechanical interaction energy, employing point charge representations of the active site, are found to be quite useful. The dielectric behaviour of the protein is much more complicated than is implicated in dielectric constant models; force fields that do not include an atomic level representation of electronic polarization are inadequate.

Animals↗
PubMed1983

Induction of osteoarthrosis in the guinea pig knee by papain.

The main purpose of this investigation was to develop a model for experimental induction of osteoarthrosis. A previously described method using papain was tried on guinea pig knee joints. Eighteen adult guinea pigs were given papain intra-articularly in the right joints; the left joints were used as controls. The animals were killed after 6 hours, 1 week, 2 weeks, 2 months, 4 months, 6 months, 8 months, and 10 months. Specimens of the articular cartilage were removed for histologic and histochemical investigation. Microscopic surface irregularities could be observed in the animals after 6 hours, 1 week, and 2 weeks, and again after 8 and 10 months. Histochemical examination of the sections from the experimental joints indicated a loss and degradation of the sulfated glycosaminoglycans. This loss was evident after 6 hours, 1 week, 2 weeks, and 8 months. The first osteoarthrotic changes were observed macroscopically after 8 months. Radiographic changes in the experimental joints could be observed in all animals killed after 10 months. It was concluded that osteoarthrosis similar to that occurring in humans can be induced by this method.

Animals↗
PubMed1990

Degradation of N5-(2-hydroxyethyl)-L-glutamine and L-glutamic acid homopolymers and copolymers by papain.

The rate of degradation of poly[N5-(2-hydroxyethyl)-L-glutamine] (PHEG), poly(L-glutamic acid) (PGA) and poly[HEG-co-GA] random copolymers by papain was measured in the pH range 4.0-7.5, employing the gel permeation chromatography method. The effect of the degree of ionization on the polymer conformation was measured by circular dichroism (c.d.). PHEG, which is uncharged, had a random coil conformation and an almost constant degradation rate within the whole pH interval. The ionization of PGA increased with increasing pH and was accompanied by conformational transition from helix to random coil. The hydrolysis of PGA by papain depended on pH with the optimum at about pH 5, indicating that both the high content of helix (at pH less than 5) and increasing charge density (at pH greater than 5), decreased the degradation rate. Contrary to PGA, pH profiles of the degradation rate of poly[HEG-co-GA] copolymers are monotonous and do not decrease at pH less than 5. In the copolymers the HEG residues act as a helix breaker and limit the formation of helical conformation. The role of structural features of a macromolecular substrate, i.e. the charge, helical conformation and the nature of amino acid residues, in the interaction between enzyme and polymer is discussed.

Chromatography, Gel↗