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lethal factor of clostridium histolyticum kills cells by apoptosis.in this study, for the first time, clostridium histolyticum lethal factor was purified by ammonium sulfate precipitation of culture broth, centrifugation through an amicon filter device and hydrophobic interaction chromatography. the purified lethal factor was devoid of proteolytic activity. at a concentration of 150 ng ml(-1) the lethal factor killed 50% of hela cells within 24 h of exposure. abrogation of actin filaments, activation of caspases, fragmentation of nuclear dna as well as ultrastr ...200717328764
differences between the fecal microbiota of coeliac infants and healthy controls.coeliac disease (cd) is an immune-mediated enteropathy with a multifactorial aetiology, characterized by chronic inflammation of the small intestinal mucosa. although evidence suggests that the gut microbiota contributes to other chronic inflammatory disorders, its possible role in cd has not been determined. in this study, the composition of the fecal microbiota of coeliac children and age-matched controls was investigated by culture-dependent and -independent methodologies, using fluorescent i ...200717489434
analysis of contribution of collagen fibre component in viscoelastic behaviour of periodontal ligament using enzyme probe.the aims of this study are to observe microscopic changes in the periodontal ligament (pdl) collagen fibres after collagenase treatment, to analyse stress-relaxation behaviour of pdl specimens treated with collagenase, and to elucidate the contribution of the collagen component to the viscoelastic behaviour of the pdl. transverse sections of rat mandibular first molars (n=24) were treated in vitro with 0, 8, 16, or 24 units of bacterial collagenase for 4h at 37 degrees c. histological specimens ...200717266965
jerusalem artichoke and chicory inulin in bakery products affect faecal microbiota of healthy volunteers.a study was conducted to test the effects of jerusalem artichoke inulin (ja) or chicory inulin (ch) in snack bars on composition of faecal microbiota, concentration of faecal scfa, bowel habit and gastrointestinal symptoms. forty-five volunteers participated in a double-blind, randomized, placebo-controlled, parallel-group study. at the end of a 7 d run-in period, subjects were randomly assigned to three groups of fifteen subjects each, consuming either snack bars with ch or ja, or snack bars wi ...200717445348
effect of bacterial collagenase on resin-dentin bonds degradation.the objective of this study is to evaluate the effect of a bacterial collagenase on the degradation of resin-dentin bonds. human dentin surfaces were bonded with: an etch-&-rinse self-priming adhesive (sb), a two-step self-etching primer/adhesive (seb), and a 1-step self-etching adhesive (oub). composite build-ups were constructed. the bonded teeth were stored (24 h, 3 months, 1 year) in distilled water or in a buffered bacterial collagenase solution. half of the specimens were stored as intact ...200717569004
antiadhesive effects of mitomycin c and streptopeptidase a in rats with intraperitoneal adhesions.intraabdominal adhesion formation is a frequent problem after major abdominal surgery. for many years, there have been various attempts to decrease adhesions by using systemic and local drugs and mechanical barriers. in this study we aimed to evaluate the antifibrinolytic antiadhesive effects of mitomycin c (mmc) and streptopeptidase a (sa) against intraabdominal adhesions. forty-eight rats were divided into six groups, each with eight rats. group 1 (sham group) rats were laparotomized by transv ...200717579872
imbalance in the composition of the duodenal microbiota of children with coeliac disease.coeliac disease (cd) is the most common immune-mediated enteropathy characterized by chronic inflammation of the small intestinal mucosa. the ingestion of gluten is responsible for the symptoms of cd, but other environmental factors are also thought to play a role in this disorder. in this study, the composition of the duodenal microbiota of coeliac children with active disease, symptom-free cd patients on a gluten-free diet and control children was determined. bacteriological analyses of duoden ...200718033837
prevalence and temporal stability of selected clostridial groups in irritable bowel syndrome in relation to predominant faecal bacteria.the differences in faecal bacterial population between irritable bowel syndrome (ibs) and control subjects have been reported in several studies. the aim of the present study was to compare the predominant and clostridial faecal microbiota of ibs subjects and healthy controls by applying denaturing gradient gel electrophoresis (dgge) and a recently developed multiplexed and quantitative hybridization-based technique, transcript analysis with the aid of affinity capture (trac). according to the r ...200616585652
qsar analysis of some 5-amino-2-mercapto-1,3,4-thiadiazole based inhibitors of matrix metalloproteinases and bacterial collagenase.a quantitative structure-activity relationship (qsar) study has been performed on 5-amino-2-mercapto-1,3,4-thiadiazole based inhibitors of matrix metalloproteinases (mmps) and a bacterial collagenase known as clostridium histolyticum collagenase (chc) to understand the structural features influencing the affinity of these inhibitors towards the enzyme. the compounds in the selected series were characterized by topological and fragmental descriptors calculated using quasar module of molecular ope ...200616682189
new worlds to explore. 200616439327
effect of a milk formula with prebiotics on the intestinal microbiota of infants after an antibiotic treatment.antibiotics exert deleterious effects on the intestinal microbiota, favoring the emergence of opportunistic bacteria and diarrhea. prebiotics are nondigestible food components that stimulate the growth of bifidobacteria. our aim was to evaluate the effects on the intestinal microbiota of a prebiotic-supplemented milk formula after an antibiotic treatment. a randomized, double-blind, controlled clinical trial was carried out in 140 infants 1-2 y of age distributed into two groups after a 1-wk amo ...200616492988
vacuolization of hela cells by a partially purified clostridium histolyticum cytotoxin.clostridium histolyticum vacuolating cytotoxin was partially purified from culture broth using ammonium sulfate precipitation, gel filtration and hydrophobic interaction chromatography. the toxin caused vacuolization of hela cells visible under a light microscope after 2 h and distinct after 8 h. transmission electron microscopy revealed the presence of numerous vacuoles, condensation of the mitochondrial matrix, increased cytoplasm density and increased amounts of heterochromatin. apoptosis was ...200616553808
an unusual cause of soft tissue infection. 200515951543
modulation of the fecal microbiota by the intake of a lactobacillus johnsonii la1-containing product in human volunteers.lactobacillus johnsonii la1 (la1) is a probiotic strain capable of stimulating the immune system of the host and interfering with gastrointestinal pathogens. this study evaluates how the ingestion of different amounts of la1 influences the main bacterial populations of the fecal microbiota. eight asymptomatic volunteers participated in the study. after a basal period, they ingested daily 100 ml of a product containing 10(8) cfu ml(-1) of la1 during the first week, 200 ml during the second week a ...200515970400
a novel galactooligosaccharide mixture increases the bifidobacterial population numbers in a continuous in vitro fermentation system and in the proximal colonic contents of pigs in vivo.prebiotics are nondigestible food ingredients that encourage proliferation of selected groups of the colonic microflora, thereby altering the composition toward a more beneficial community. in the present study, the prebiotic potential of a novel galactooligosaccharide (gos) mixture, produced by the activity of galactosyltransferases from bifidobacterium bifidum 41171 on lactose, was assessed in vitro and in a parallel continuous randomized pig trial. in situ fluorescent hybridization with 16s r ...200515987856
[substrate specificity of collagenase of streptomyces sp. 1349 and keratinase of streptomyces sp. 1382].the paper determines the action specificity concerning the bonding type of collagenases of strepomyces sp. 1349 and keratinases of streptomyces sp. 1382. experimental data obtained evidence for the wide specificity of the obtained enzymatic drugs. it has been established that both collagenases and keratinases display high specificity in respect of the bonds made by the residues of hydrophobic amino acids. collagenases of streptomyces sp. 1349, as to their wide action specificity, differed from c ...200516018211
determination of the cytotoxic effect of clostridium histolyticum culture supernatant on hela cells in the presence of protease inhibitors.clostridium histolyticum culture supernatant contains numerous enzymes, which exert a cytotoxic effect on host cells. this includes lethal toxin, clostripain and high-potassium-sensitive toxin. since the number of c. histolyticum infections increased during the last several years, it seems worthwhile to evaluate whether protease inhibitors, used for the treatment of many diseases, could influence toxicity, and thus, pathogenicity of c. histolyticum. in this study we evaluated in vitro the influe ...200516051065
inhibition of collagenase by naturally-occurring flavonoids.we examined the inhibitory activities of various flavonoids, including the flavanones, flavones/isoflavones and flavonols, on collagenase from clostridium histolyticum to establish their therapeutic potential against skin inflammation and photoaging. in general, the flavonols were stronger inhibitors than the flavones/isoflavones, and this indicated the importance of the c-3 hydroxyl substitution. quercetin was the most active flavonoid among those tested, and it showed an ic50 of 286 microm. th ...200516276971
differences between the gut microflora of children with autistic spectrum disorders and that of healthy children.children with autistic spectrum disorders (asds) tend to suffer from severe gastrointestinal problems. such symptoms may be due to a disruption of the indigenous gut flora promoting the overgrowth of potentially pathogenic micro-organisms. the faecal flora of patients with asds was studied and compared with those of two control groups (healthy siblings and unrelated healthy children). faecal bacterial populations were assessed through the use of a culture-independent technique, fluorescence in s ...200516157555
the structure-function relationship in the clostripain family of peptidases.in this study we investigate the active-site structure and the catalytic mechanism of clostripain by using a combination of three separate techniques: affinity labelling, site-directed mutagenesis and molecular modelling. a benzamidinyl-diazo dichlorotriazine dye (bdd) was shown to act as an efficient active site-directed affinity label for clostridium histolyticum clostripain. the enzyme, upon incubation with bdd in 0.1 m hepes/naoh buffer ph 7.6, exhibits a time-dependent loss of activity. the ...200415009210
factor xiii contrasts the effects of metalloproteinases in human dermal fibroblast cultured cells.matrix metalloproteinases (mmps) are overexpressed in venous leg ulcers, determining a breakdown of the main extracellular matrix (ecm) components owing mainly to collagenase activities, and so playing a crucial role in ulcer pathogenesis. the authors studied the effects of coagulation factor xiii (fxiii), which cross-links collagen and other ecm components, in human fibroblast cultured cells in the presence and in the absence of matrix metalloproteinases from clostridium histolyticum collagenas ...200415490040
improved enzymatic isolation of fibroblasts for the creation of autologous skin substitutes.the number of medical applications using autologous fibroblasts is increasing rapidly. we investigated thoroughly the procedure to isolate cells from skin using the enzymatic tissue dissociation procedure. tissue digestion efficiency, cell viability, and yield were investigated in relation to size of tissue fragments, digestion volume to tissue ratio, digestion time, and importance of other protease activities present in clostridium histolyticum collagenase (chc) (neutral protease, clostripain, ...200415723562
inhibition effects of (+)-catechin-aldehyde polycondensates on proteinases causing proteolytic degradation of extracellular matrix.inhibition effects of (+)-catechin-aldehyde polycondensates against the activity of proteinases, clostridium histolyticum collagenase (chc) and human neutrophil elastase (hne) causing proteolytic degradation of extracellular matrix (ecm), have been investigated. in normal tissues, a balance is reached between the formation and destruction of ecm, leading to a state of homeostasis. however, uncontrolled destruction of ecm contributes to tumor invasion and metastasis. in the measurement of the inh ...200415207729
quantitative analysis of the impact of the organic matrix on the fluoride effect on erosion progression in human dentine using longitudinal microradiography.after an initial demineralisation, an intensive fluoridation is capable of inhibiting the erosive mineral loss in dentine completely, which might be related to the presence of the exposed organic dentine matrix. aim of the present study was, therefore, to evaluate whether fluoride is also effective when the organic material is removed. the study was a cyclic de- and remineralisation model over 5 days in vitro. samples from human coronal dentine were demineralised with citric acid (ph 2.3; 6 x 10 ...200415353250
interaction of aldehydes with collagen: effect on thermal, enzymatic and conformational stability.stabilization of type i rat tail tendon (rtt) collagen by various aldehydes, viz. formaldehyde, gluteraldehyde, glyoxal and crotanaldehyde was studied to understand the effect of each on the thermal, enzymatic and conformational stability of collagen. the aldehydes have been found to increase the heat stability of rat tail tendon collagen fibres from 62 to 77-86 degrees c. the increase in thermal stability was found to be in a species dependent manner. the variation in the thermal stability of c ...200415374680
outbreak of clostridium histolyticum infections in injecting drug users in england and scotland.clostridial infections in injecting drug users in the united kingdom are a relatively new phenomenon that came to light in 2000 when cases of serious illness and deaths due to clostridium novyi were recorded. in the period december 2003 to april 2004, the anaerobe reference laboratory received twelve referrals of an extremely rare isolate, clostridium histolyticum, from cases of infection in injecting drug users submitted from nine different hospitals in england and scotland. molecular typing of ...200415381836
quantum theoretic qsar of benzene derivatives: some enzyme inhibitors.our previously developed approach to the development of qsar equations for benzene derivatives, originally for phenylalkylamine hallucinogens, has been applied to four new systems: sulfonamide inhibitors of the enzymes carbonic anhydrase, thrombin, trypsin, and clostridium histolyticum collagenase. the novel features involve the energies and nodal orientations of pi-like orbitals, and an allowance for the symmetry of the benzene nucleus. the resulting equations give better fits, better predictiv ...200415499995
a bacterial collagen-binding domain with novel calcium-binding motif controls domain orientation.the crystal structure of a collagen-binding domain (cbd) with an n-terminal domain linker from clostridium histolyticum class i collagenase was determined at 1.00 a resolution in the absence of calcium (1nqj) and at 1.65 a resolution in the presence of calcium (1nqd). the mature enzyme is composed of four domains: a metalloprotease domain, a spacing domain and two cbds. a 12-residue-long linker is found at the n-terminus of each cbd. in the absence of calcium, the cbd reveals a beta-sheet sandwi ...200312682007
protease inhibitors: synthesis of bacterial collagenase and matrix metalloproteinase inhibitors incorporating arylsulfonylureido and 5-dibenzo-suberenyl/suberyl moieties.novel matrix metalloproteinase (mmp)/bacterial collagenase inhibitors are reported, considering the sulfonylated amino acid hydroxamates as lead molecules. a series of compounds was prepared by reaction of arylsulfonyl isocyanates with n-(5h-dibenzo[a,d]cyclohepten-5-yl)- and n-(10,11-dihydro-5h-dibenzo[a,d]cyclohepten-5-yl) methyl glycocolate, respectively, followed by the conversion of the coome to the carboxylate/hydroxamate moieties. the corresponding derivatives with methylene and ethylene ...200312713832
a comparative qsar study on carbonic anhydrase and matrix metalloproteinase inhibition by sulfonylated amino acid hydroxamates.a quantitative structure-activity relationship (qsar) study is made on the inhibition of a few isozymes of carbonic anhydrase (ca) and some matrix metalloproteinases (mmps), both zinc containing families of enzymes, by sulfonylated amino acid hydroxamates. for both enzymes, the inhibition potency of the hydroxamates is found to be well correlated with kier's first-order valence molecular connectivity index 1chi(v) of the molecule and electrotopological state indices of some atoms. from the resul ...200312751815
a quantitative structure-activity relationship study on clostridium histolyticum collagenase inhibitors: roles of electrotopological state indices.a quantitative structure-activity relationship (qsar) study has been made on eight different series of clostridium histolyticum collegenase (chc) inhibitors. these series are comprised of four different groups of sulfonylated amino acids and their corresponding hydroxamates. in each series, the inhibition potency of the compounds has been found to be significantly correlated with the electrotopological state (e-state) indices of nitrogen and sulfur atoms of the sulfonylated amino group in the mo ...200312818668
inhibition of collagenase and metalloproteinases by aloins and aloe gel.the effects of aloe barbadensis gel and aloe gel constituents on the activity of microbial and human metalloproteinases have been investigated. clostridium histolyticum collagenase (chc) results dose-dependently inhibited by aloe gel and the activity-guided fractionation led to an active fraction enriched in phenolics and aloins. aloins have been shown to be able to bind and to inhibit chc reversibly and non-competitively. aloe gel and aloins are also effective inhibitors of stimulated granulocy ...200312479983
a quantitative structure-activity relationship study on some matrix metalloproteinase and collagenase inhibitors.a quantitative structure-activity relationship (qsar) study is made on some hydroxamic acid-based inhibitors of matrix metalloproteinases (mmps) and a bacterial collagenase, namely clostridium histolyticum collagenase (chc), that also belongs to an mmp family, m-31, using kier's valence molecular connectivity index (1)chi(v) of the substituents and electrotopological state (e-state) indices of some atoms. the results indicate that out of the four mmps (mmp-1, mmp-2, mmp-8, and mmp-9) studied, mm ...200312517437
pcr detection of clostridium chauvoei in pure cultures and in formalin-fixed, paraffin-embedded tissues.the polymerase chain reaction (pcr) was used to amplify specific segments of the 16s ribosomal rna gene of clostridium chauvoei, a major pathogen of ruminants. three sets of primers were used to produce amplicons of 159, 836 and 959 base pairs (bp), respectively. the pcr was evaluated by testing clinically important strains of clostridium, including 21 strains of c. chauvoei, five strains each of clostridium septicum and clostridium perfringens and two strains each of clostridium novyi, clostrid ...200312458172
protease inhibitors: synthesis of bacterial collagenase and matrix metalloproteinase inhibitors incorporating succinyl hydroxamate and iminodiacetic acid hydroxamate moieties.a series of succinyl hydroxamates/bishydroxamates as well as a new structural type of matrix metalloproteinase (mmp)/bacterial protease (bp) inhibitors, incorporating iminodiacetic (ida) hydroxamate/bishydroxamate moieties, has been synthesized and tested for interaction with four vertebrate proteases, mmp-1, mmp-2, mmp-8 and mmp-9, and a bp, the collagenase isolated from clostridium histolyticum (chc). the new derivatives generally showed inhibition constants in the range of 8-62 nm against the ...200314506914
rapid determination of substrate specificity of clostridium histolyticum beta-collagenase using an immobilized peptide library.the molecular basis of the substrate specificity of clostridium histolyticum beta-collagenase was investigated using a combinatorial method. an immobilized positional peptide library, which contains 24,000 sequences, was constructed with a 7-hydroxycoumarin-4-propanoyl (cop) fluorescent group attached at the n terminus of each sequence. this immobilized peptide library was incubated with c. histolyticum beta-collagenase, releasing fluorogenic fragments in the solution phase. the relative substra ...200211724807
protease inhibitors: synthesis of matrix metalloproteinase and bacterial collagenase inhibitors incorporating 5-amino-2-mercapto-1,3,4-thiadiazole zinc binding functions.matrix metalloproteinase (mmp)/bacterial collagenase inhibitors incorporating 5-amino-2-mercapto-1,3,4-thiadiazole zinc binding functions are reported. a series of compounds was prepared by reaction of arylsulfonyl isocyanates or arylsulfonyl halides with phenylalanyl-alanine, followed by coupling with 5-amino-2-mercapto-1,3,4-thiadiazole in the presence of carbodiimides. these new compounds were assayed as inhibitors of human mmp-1, mmp-2, mmp-8 and mmp-9, and of the collagenase isolated from t ...200212217351
collagenase-induced changes in articular cartilage as detected by electron-microscopic stereology, quantitative polarized light microscopy and biochemical assays.the purpose of this study was to compare the ability of electron-microscopic (em) stereology with quantitative polarized light microscopy (plm) and biochemical collagen (hydroxyproline) and crosslink (pyridinoline) analyses to detect changes in the superficial collagen network of bovine articular cartilage after digestion in vitro with purified bacterial (clostridium histolyticum) collagenase (30 u/ml) for 24 and 48 h. collagen volume (v(v)) and surface (s(v)) densities of the uppermost third of ...200212566629
bacterial protease inhibitors.serine-, cysteine-, and metalloproteases are widely spread in many pathogenic bacteria, where they play critical functions related to colonization and evasion of host immune defenses, acquisition of nutrients for growth and proliferation, facilitation of dissemination, or tissue damage during infection. since all the antibiotics used clinically at the moment share a common mechanism of action, acting as inhibitors of the bacterial cell wall biosynthesis or affecting protein synthesis on ribosome ...200212111749
free fatty acids inhibit the activity of clostridium histolyticum collagenase and human neutrophil elastase.we investigated the ability of free fatty acids to inhibit the activity of clostridium histolyticum collagenase (ec 3.4.24.3) and human neutrophil elastase (ec 3.4.21.37). we determined the activity of collagenase by degradation of resorufin-labeled casein fluorimetrically. the determination of the elastase activity was performed by a spectrophotometric method using a 4-nitroanilide peptide substrate. we found that most of the tested fatty acids inhibited collagenase at concentrations between 50 ...200212357383
screening of selected basidiomycetes for inhibitory activity on clostridium histolyticum collagenase and human leukocyte elastase.collagenase and elastase play a critical role in the degradation of connective tissue. aqueous and dichloromethane extracts of 15 basidiomycetes were screened for their ability to inhibit the activity of collagenase and elastase. collagenase (ec 3.4.24.3) was not inhibited by aqueous extracts, but by dichloromethane extracts in concentrations of 200 microg/ml. for seven extracts an ic(50) less than 200 microg/ml could be observed. elastase (3.4.21.37) was inhibited by both aqueous and dichlorome ...200211933148
mucosal and invading bacteria in patients with inflammatory bowel disease compared with controls.endogenous intestinal bacteria and/or specific bacterial pathogens are suspected of being involved in the pathogenesis of inflammatory bowel diseases (ibd). the aim of this study was to investigate ibd tissues for different bacterial population groups harbouring the mucosal surface and/or invading the mucosa.200212374228
collagen-binding domain of a clostridium histolyticum collagenase exhibits a broad substrate spectrum both in vitro and in vivo.the substrate spectrum of the tandem collagen-binding domain (cbd) of clostridium histolyticumclass i collagenase (colg) was examined both in vitro and in vivo. cbd bound to insoluble type i, ii, iii and iv collagens in vitro, and to skin, aorta, tendon, kidney, trachea and corneal tissues containing various types of collagen fibrils or sheets. cbd bound to all kinds of collagen fibrils regardless of their diameters and also bound to sheet-forming collagen in the glomerular basal lamina or desce ...200111913772
characterization of an important enzymatic component in collagenase that is essential for the effective digestion of the human and porcine pancreas.recent clinical results from edmonton have demonstrated the feasibility of achieving normoglycemia in type i diabetic patients by islet transplantation. one of the key issues in obtaining this success was transplanting sufficient numbers of islets by sequential transplants. although the development of semipurified endotoxin-free clostridium histolyticum-derived collagenase (liberase) has improved islet yields from the human pancreas, batch-to-batch variation and loss of activity with time still ...200111814113
a thermostable collagenolytic protease with a very large molecular mass produced by thermophilic bacillus sp. strain mo-1.a collagenolytic protease was purified to homogeneity from thermophilic bacillus sp. strain mo-1. the protease from strain mo-1 showed high activity toward type i and iv collagens and gelatin. however, peptide substrates (4-phenylazobenzyloxycarbonyl-pro-leu-gly-pro-arg and 2-furylacryloyl-leu-gly-pro-ala) for collagenases were inert as substrates. the collagenolytic protease cleaved oxidized insulin b-chain at 11 sites and degraded type i and iv collagens into anonymous small pieces, suggesting ...200111693905
substrate recognition by the collagen-binding domain of clostridium histolyticum class i collagenase.clostridium histolyticum type i collagenase (colg) has a segmental structure, s1+s2+s3a+s3b. s3a and s3b bound to insoluble collagen, but s2 did not, thus indicating that s3 forms a collagen-binding domain (cbd). because s3a+s3b showed the most efficient binding to substrate, cooperative binding by both domains was suggested for the enzyme. monomeric (s3b) and tandem (s3a+s3b) cbds bound to atelocollagen, which contains only the collagenous region. however, they did not bind to telopeptides immo ...200111121400
salivary histatin 5 is a potent competitive inhibitor of the cysteine proteinase clostripain.histatin 5 is a low molecular weight salivary protein which is known to exhibit inhibitory activity against several proteinases, including the cysteine proteinases gingipains. the purpose of this study was to characterize the effect of salivary histatin on the proteolytic activity of the cysteine proteinase clostripain derived from the pathogen clostridium histolyticum. using a synthetic nitroanilide substrate, we studied in detail the inhibition of clostripain by histatin 5 and compared the eff ...200111231021
protease inhibitors: synthesis of a series of bacterial collagenase inhibitors of the sulfonyl amino acyl hydroxamate type.a series of sulfonyl amino acyl hydroxamates incorporating alkyl/arylsulfonyl-n-2-nitrobenzyl-l-alanine was prepared. related compounds were obtained by reaction of n-2-nitrobenzyl-l-ala with aryl isocyanates, arylsulfonyl isocyanates, or benzoyl isothiocyanate, followed by the conversion of the cooh into the conhoh moiety. the new compounds were assayed as inhibitors of the clostridium histolyticum collagenase (chc), a bacterial protease involved in the degradation of extracellular matrix. many ...200111405662
oligofructose and long-chain inulin: influence on the gut microbial ecology of rats associated with a human faecal flora.dietary incorporation of fermentable, indigestible fructans may be of benefit to gastrointestinal health by providing short-chain fatty acids, stimulating the proliferation of bifidobacteria or lactobacilli and suppressing potential pathogenic organisms in the gut. we tested the hypothesis that the effects of fructans on caecal, colonic and faecal short-chain fatty acid concentration and microflora composition depend on their chain length. germ-free rats associated with a human faecal flora were ...200111502244
protease inhibitors. part 8: synthesis of potent clostridium histolyticum collagenase inhibitors incorporating sulfonylated l-alanine hydroxamate moieties.a series of hydroxamates was prepared by reaction of alkyl/arylsulfonyl halides with n-2-chlorobenzyl-l-alanine, followed by conversion of the cooh moiety to the conhoh group, with hydroxylamine in the presence of carbodiimides. other structurally related compounds were obtained by reaction of n-2-chlorobenzyl-l-alanine with aryl isocyanates, arylsulfonyl isocyanates or benzoyl isothiocyanate, followed by the similar conversion of the cooh into the conhoh moiety. the new compounds were assayed a ...200010732980
protease inhibitors: synthesis of clostridium histolyticum collagenase inhibitors incorporating sulfonyl-l-alanine hydroxamate moieties.a series of hydroxamates was obtained by the reaction of n-(4-nitrobenzyl)-l-alanine with alkyl/arylsulfonyl halides, followed by conversion of the cooh group into conhoh. structurally-related compounds were prepared similarly by using arylsulfonyl isocyanates, aryl isocyanates or arylsulfenyl halides instead of the sulfonyl halides. many of the new compounds showed nanomolar affinity for the bacterial collagenase isolated from the pathogen clostridium histolyticum.200010743957
infective endocarditis due to clostridium histolyticum. 200011168053
protease inhibitors: synthesis of l-alanine hydroxamate sulfonylated derivatives as inhibitors of clostridium histolyticum collagenase.l-alanine hydroxamate derivatives were obtained by reaction of alkyl/arylsulfonyl halides with l-alanine, followed by treatment with benzyl chloride, and conversion of the cooh moiety to the conhoh group with hydroxylamine in the presence of carbodiimides. other derivatives were obtained by reaction of n-benzyl-alanine with aryl isocyanates, arylsulfonyl isocyanates or benzoyl isothiocyanate, followed by a similar conversion of the cooh to the conhoh moiety. the obtained compounds were assayed a ...200010938538
protease inhibitors. part 7. inhibition of clostridium histolyticum collagenase with sulfonylated derivatives of l-valine hydroxamate.sulfonylated l-valine hydroxamate derivatives were obtained by reaction of alkyl/arylsulfonyl halides with the title amino acid, followed by treatment with benzyl chloride, and conversion of the cooh moiety to the conhoh group. other derivatives were obtained by reaction of n-benzyl-l-valine with arylisocyanates, arylsulfonylisocyanates or benzoylisothiocyanate, followed by the similar conversion of the cooh into the conhoh moiety, with hydroxylamine in the presence of carbodiimides. the obtaine ...200010699384
carbonic anhydrase and matrix metalloproteinase inhibitors: sulfonylated amino acid hydroxamates with mmp inhibitory properties act as efficient inhibitors of ca isozymes i, ii, and iv, and n-hydroxysulfonamides inhibit both these zinc enzymes.the 14 different carbonic anhydrase (ca, ec 4.2.1.1) isozymes as well as the 23 different matrix metalloproteinases (mmps) isolated up to now in higher vertebrates play important physiological functions in these organisms. unsubstituted sulfonamides act as high-affinity inhibitors for the first type of these enzymes, whereas hydroxamates strongly inhibit the latter ones. since the active site geometry around the zinc ion in these two types of metalloenzymes is rather similar, we tested whether s ...200011020282
effects of the non-peptide b2 receptor antagonist fr173657 in models of visceral and cutaneous inflammation.the non-peptide b2 receptor antagonist (e)-3-(6-acetamido-3-pyridyl)-n-[n-[2,4-dichloro-3-[(2-methyl-8-quinolin yl)oxymethyl]phenyl]-n-methylaminocarbonylmethyl]acrylamide (fr173657) was compared to the peptide antagonist icatibant in models of visceral and cutaneous inflammation.200011089906
atomic force microscopy of intact and digested collagen molecules.the present study was performed to analyse the structure of non-digested and digested collagen type i molecules by atomic force microscopy (afm). collagen type i molecules from the bovine skin were diluted with 0.05 n acetic acid, spread on a mica plate, air-dried and observed by non-contact mode afm in air. collagen molecules digested with clostridium histolyticum collagenase were also examined by afm. intact collagen type i molecules were observed as twisted threads ranging mainly between 280 ...200011108030
protease inhibitors - part 5. alkyl/arylsulfonyl- and arylsulfonylureido-/arylureido- glycine hydroxamate inhibitors of clostridium histolyticum collagenase.reaction of alkyl/arylsulfonyl halides with glycine afforded a series of derivatives which were first n-benzylated by treatment with benzyl chloride, and then converted to the corresponding hydroxamic acids with hydroxylamine in the presence of carbodiimide derivatives. other derivatives were obtained by reaction of n-benzyl-glycine with aryl isocyanates, arylsulfonyl isocyanates or benzoyl isothiocyanate, followed by conversion of their cooh group into the conhoh moiety, as mentioned above. the ...200010785556
protease inhibitors: synthesis of potent bacterial collagenase and matrix metalloproteinase inhibitors incorporating n-4-nitrobenzylsulfonylglycine hydroxamate moieties.a series of compounds was prepared by reaction of alkyl/arylsulfonyl halides with n-4-nitrobenzylglycine, followed by conversion of the cooh to the conhoh group, with hydroxylamine in the presence of carbodiimides. other structurally related compounds were obtained by reaction of n-4-nitrobenzylglycine with aryl isocyanates, arylsulfonyl isocyanates, or benzoyl isothiocyanate, followed by the similar conversion of the cooh into the conhoh moiety. another subseries of derivatives was prepared fro ...200010794702
protease inhibitors. part 12. synthesis of potent matrix metalloproteinase and bacterial collagenase inhibitors incorporating sulfonylated n-4-nitrobenzyl-beta-alanine hydroxamate moieties.n-4-nitrobenzyl-beta-alanine was reacted with alkyl/arylsulfonyl halides, followed by conversion of the cooh to the conhoh group. structurally related compounds were obtained by reaction of n-4-nitrobenzyl-beta-alanine with aryl isocyanates, arylsulfonyl isocyanates or benzoyl isothiocyanate, followed by similar conversion of the cooh into the conhoh moiety. another subseries of derivatives was prepared from sulfanilyl- or metanilyl-4-nitrobenzyl-beta-alanine by reaction with arylsulfonyl isocya ...200010913755
metal content and biochemical analyses of a recombinant collagenase prtv from vibrio parahaemolyticus.prtv is an extracellular metalloprotease of vibrio parahaemolyticus and regarded as a collagenase. inductively coupled plasma-optical emission spectrometry analysis indicated that the recombinant prtv contains 1 mol of zinc per mol of the native enzyme. on the basis of a kinetic study using 2-furanacryloyl-leu-gly-pro-ala (falgpa, the specific substrate for bacterial collagenase) as a substrate, it was suggested that metal ions may play a significant role in the binding and catalytic steps of th ...200011128063
the 105-kda protein component of bacillus cereus non-haemolytic enterotoxin (nhe) is a metalloprotease with gelatinolytic and collagenolytic activity.a sequence of 91 amino acids residues, probably starting from the n-terminal of the mature protein, was determined for the 105-kda protein of the non-haemolytic enterotoxin of bacillus cereus. the last part of this sequence was similar to parts of the n-terminal portions of two collagenases of clostridium histolyticum and clostridium perfringens. zymography, with intact collagen fibril and gelatin as substrates, showed that the 105-kda protein had collagenolytic and gelatinolytic activity. the 1 ...199910499286
gene duplication and multiplicity of collagenases in clostridium histolyticum.clostridium histolyticum collagenase contains a number of different active components. previously we have shown that colh encodes a 116-kda collagenase (colh) and a 98-kda gelatinase. we purified a different 116-kda collagenase (colg) from the culture supernatant and sequenced its gene (colg). we also identified four other gelatinases (105, 82, 78, and 67 kda) and determined their n-terminal amino acid sequences, all of which coincided with that of either colg or colh. hybridization experiments ...19999922257
identification of metal ligands in the clostridium histolyticum colh collagenase.a clostridium histolyticum 116-kda collagenase has an h415exxh motif but not the third zinc ligand, as found in already characterized zinc metalloproteinases. to identify its catalytic site, we mutated the codons corresponding to the three conserved residues in the motif to other amino acid residues. the mutation affecting his415 or his419 abolished catalytic activity and zinc binding, while that affecting glu416 did the former but not the latter. these results suggest that the motif forms the c ...199910217773
imaging real-time proteolysis of single collagen i molecules with an atomic force microscope.the dynamic process of synthesis and degradation of extracellular matrix molecules, including various collagens, is important in normal physiological functions and pathological conditions. existing models of collagen enzymatic degradation reactions are derived from bulk biochemical assays. in this study, we have imaged in real-time individual collagen i molecules and their proteolysis by clostridium histolyticum collagenases in phosphate-buffered saline (pbs) with atomic force microscopy (afm). ...199910433702
collagen-binding growth factors: production and characterization of functional fusion proteins having a collagen-binding domain.the autocrine/paracrine peptide signaling molecules such as growth factors have many promising biologic activities for clinical applications. however, one cannot expect specific therapeutic effects of the factors administered by ordinary drug delivery systems as they have limited target specificity and short half-lives in vivo. to overcome the difficulties in using growth factors as therapeutic agents, we have produced fusion proteins consisting of growth factor moieties and a collagen-binding d ...19989618531
variations of bacterial populations in human feces measured by fluorescent in situ hybridization with group-specific 16s rrna-targeted oligonucleotide probes.six 16s rrna-targeted oligonucleotide probes were designed, validated, and used to quantify predominant groups of anaerobic bacteria in human fecal samples. a set of two probes was specific for species of the bacteroides fragilis group and the species bacteroides distasonis. two others were designed to detect species of the clostridium histolyticum and the clostridium lituseburense groups. another probe was designed for the genera streptococcus and lactococcus, and the final probe was designed f ...19989726880
a study of the collagen-binding domain of a 116-kda clostridium histolyticum collagenase.the clostridium histolyticum 116-kda collagenase consists of four segments, s1, s2a, s2b, and s3. a 98-kda gelatinase, which can degrade denatured but not native collagen, lacks the c-terminal fragment containing a part of s2b and s3. in this paper we have investigated the function of the c-terminal segments using recombinant proteins. full-length collagenase degraded both native type i collagen and a synthetic substrate, pz-peptide, while an 88-kda protein containing only s1 and s2a (s1s2a) deg ...19989452493
[the influences of lanthanum,cerium and fluorine ions to the activity of collagenase degrading cemental collagens]the influences of trace elements lanthanum,cerium and fluorine to the activity of clostridium histolyticum collagenase(chc) during the period of chc degrading the cemental root collagen in vitro is studied.the results reveal that la(3+) can significantly inhibit the activity of the chc than ce(3+) and f(-). therefore it suggests that lanthanum may be used as a new kind of element in preventing root caries.the mechanisms of above functions are also discussed.199715159961
a trypanosoma cruzi-secreted 80 kda proteinase with specificity for human collagen types i and iv.specific interactions between parasites and extracellular matrix components are an important mechanism in the dissemination of chagas' disease. binding of the extracellular matrix proteins to trypanosoma cruzi receptors has been described as a significant step in this phenomenon. in this study, a specific proteinase activity was identified in cell-free extracts of amastigote, trypomastigote and epimastigote forms of t. cruzi using the collagenase fluorogenic substrate n-suc-gly-pro-leu-gly-pro-7 ...19979224638
histochemical analysis of the role of class i and class ii clostridium histolyticum collagenase in the degradation of rat pancreatic extracellular matrix for islet isolation.to understand why class ii clostridium histolyticum collagenase is much more effective than class i in the isolation of rat pancreatic islets, we analyzed the role of these collagenases in pancreatic tissue dissociation. crude collagenase was purified and then fractionated into class i and ii with different enzyme activities and protein compositions. pancreatic tissue was incubated with either class i, class ii, or class i + ii, with or without added protease, under conditions that eliminated en ...19979258514
involvement of 5-hydroxytryptamine and bradykinin in the hyperalgesia induced in rats by collagenase from clostridium histolyticum.the involvement of bradykinin, 5-hydroxytryptamine, substance p and prostanoids in the hyperalgesia elicited by collagenase in rat paw was investigated. collagenase (100 micrograms) induced a slight hyperalgesia in kininogen deficient rats in comparison with the behavioural response obtained in normal rats. lisinopril (10(-5) m), and angiotensin-converting enzyme inhibitor, increased the duration of the hyperalgesia elicited in normal rats. ondansetron (0.5 to 5 mumol/kg), a 5-ht3 antagonist, su ...19979151293
identification and analysis of a collagenolytic activity in streptococcus mutans.streptococcus mutans is an important pathogen in coronal caries and is implicated in dental root decay by its ability to bind collagen from various sources. in the present study, electron microscopic analysis demonstrated the ability of s. mutans to bind and to disrupt collagen fibrils of the amniotic membrane. the synthetic peptide falgpa, which is similar in structure to collagen, was degraded by s. mutans, with a lower level of falgpa hydrolytic activity observed in sucrose-grown cells compar ...19978939802
expression of the colh gene encoding clostridium histolyticum collagenase in bacillus subtilis and its application to enzyme purification.the colh gene encoding 116-kda collagenase of clostridium histolyticum (ccolh) was cloned into an escherichia coli-bacillus subtilis shuttle vector to develop a method for purification of recombinant collagenase (rcolh). when plasmid pjcm310 containing the colh gene was introduced into b. subtilis db104 and the transformant was grown in lb broth at 37 c, stability of the plasmid was not maintained. however, stability was partly improved by growing the transformant in a modified lb broth containi ...19969013490
fractions from commercial collagenase preparations: use in enzymic isolation of the islets of langerhans from porcine pancreas.transplantation of isolated islets of langerhans is an intriguing possibility for the treatment of diabetes mellitus. the isolation of islets from pancreata requires the specific dissociation of the tissue. commercial collagenases from clostridium histolyticum are widely used for this purpose. unfortunately, the effectiveness of these commercial enzymes is not predictable and differs considerably between suppliers and even from lot to lot. this is due mainly to differences in their specific coll ...19968889213
[collagenolytic enzymes synthesized by microorganisms].the review uses data obtained by the authors and available in the literature to discuss microbial collagenolytic enzymes, widely employed in scientific research, biotechnology, and medicine. collagenases differing in their structure and the specificity of their action on collagen fibrils were isolated from bacteria (including marine isolates), actinomycetes, and fungi. collagenases produced by clostridium histolyticum and achromobacter iophagus are the best studied enzymes; both are metalloenzym ...19968992239
demonstration that 1-trans-epoxysuccinyl-l-leucylamido-(4-guanidino) butane (e-64) is one of the most effective low mr inhibitors of trypsin-catalysed hydrolysis. characterization by kinetic analysis and by energy minimization and molecular dynamics simulation of the e-64-beta-trypsin complex.1-trans-epoxysuccinyl-l-leucylamido(4-guanidino)butane (e-64) was shown to inhibit beta-trypsin by a reversible competitive mechanism; this contrasts with the widely held view that e-64 is a class-specific inhibitor of the cysteine proteinases and reports in the literature that it does not inhibit a number of other enzymes including, notably, trypsin. the k1, value (3 x 10(-5) m) determined by kinetic analysis of the hydrolysis of n alpha-benzoyl-l-arginine 4-nitroanilide in tris/hcl buffer, ph ...19968670152
clostripain linker deletion variants yield active enzyme in escherichia coli: a possible function of the linker peptide as intramolecular inhibitor of clostripain automaturation.the clostripain core protein is composed of the light and heavy chain subunits linked by a nonapeptide into a single polypeptide chain [mol. gen. genet. 240: 140, 1993]. linker removal is due to autocatalytic processing yielding active heterodimeric enzyme. we have expressed mutationally altered core protein variants in the heterologous host escherichia coli to gain further insight into the process of clostripain automaturation. in a mutationally created cys231 --> ser variant, heterodimer forma ...19968875906
active site structure of a hemagglutinating protease from porphyromonas gingivalis: similarity to clostripain.the active site of a 44-kda hemagglutinating arginine-specific protease from the putative periodontopathogen porphyromonas gingivalis was specifically labeled with n alpha-[3h]acetyllysine chloromethyl ketone. after enzymatic digestion of the labeled enzyme, a labeled active site peptide was isolated by hplc. the sequence of the active site peptide was determined, after its treatment with nabh4 to reduce the ketone group of the reagent moiety, to be asp-val-ala-cys-val-asn-gly. the cysteine resi ...19958595395
a simple in vitro method for evaluating the efficacy of different batches of crude clostridium histolyticum collagenase for islet isolation. 19958539957
university of wisconsin solution inhibits the class ii collagenase within crude clostridium histolyticum collagenase. 19958539958
recombinant enzymes for islet isolation: purification of a collagenase from clostridium histolyticum and cloning/expression of the gene. 19958539959
augmentation of permeability in the bronchial epithelium by the house dust mite allergen der p1.sequence analyses have revealed the existence of homology between certain aeroallergens and proteolytic enzymes. this homology can be expressed functionally, but its significance to airway pathophysiology is unknown. studies with madin-darby canine kidney cells and canine tracheal epithelial cells grown on plastic substrata or matrix proteins suggest that der p1, a major allergen from the house dust mite dermatophagoides pteronyssinus and a cysteine proteinase, or the unfractionated growth mediu ...19957695916
different roles of class i and class ii clostridium histolyticum collagenase in rat pancreatic islet isolation.crude clostridium histolyticum collagenase was purified by gel filtration and fractionated by anion exchange chromatography into class i with high collagen digestion activity (cda) and low falgpa (2-furanacryloyl-l-leucylglycyl-l-prolyl-l-alanine) hydrolysis activity (fha), class ii with low cda and high fha, and a fraction called class i/ii with intermediate activities. the roles of these collagenase classes in rat pancreatic islet isolation were investigated. dissociations were carried out wit ...19957859945
mediation by bradykinin of rat paw oedema induced by collagenase from clostridium histolyticum.1. collagenases are thought to play a major role in the pathology of gas gangrene caused by clostridium histolyticum, because they can destroy the connective tissue barriers. we investigated possible mediators involved in the oedema formation and plasma protein extravasation which follow the injection of a collagenase (ec 3.4.24.3) from clostridium histolyticum into one hind paw of anaesthetized rats. 2. the magnitude of the oedema following a subplantar injection was dependent on the dose of co ...19947915609
[proteinases with various substrate specificities in structural studies of yeast cell walls].different proteins are revealed in cell wall of yeast cells candida utilis by means of specific proteolysis with subtilisins tv and 72, trypsin and purified collagenase of clostridium histolyticum. some of them were characterized by resistance to trypsin and sensitivity to subtilisin tv. in young cells this group is represented essentially by a protein of 33 kd, which appears to be one of the structural proteins, binding fibrillae of carbohydrate. other proteins proved to be sensitive to both tr ...19947945458
cell-associated collagenolytic activity by group b streptococci.group b streptococci (gbs) are important pathogens in neonatal sepsis, pneumonia, and meningitis. the ability of gbs to invade the collagen-rich amniotic membrane of the placenta has been shown in vitro. in the presence of gbs, the collagen fibrils of the amnion appear disordered, suggesting a role for gbs in premature rupture of membranes. sodium dodecyl sulfate-polyacrylamide gel electrophoresis, sephadex g-200 column chromatography, and gelatin zymograms were used in this study to characteriz ...19947960147
heterologous expression of the clostripain gene from clostridium histolyticum in escherichia coli and bacillus subtilis: maturation of the clostripain precursor is coupled with self-activation.clostripain-specific antibodies were used to analyse the maturation of clostripain prepro-enzyme and core protein heterologously synthesized in escherichia coli and bacillus subtilis. core protein purified from e. coli cells harbouring plasmid phm3-23 underwent calcium-dependent, self-triggered maturation. concomitantly, the inactive form of the enzyme was converted into an active form, demonstrating the self-activation capacity of the clostripain core protein. as judged from western blot analys ...19948025682
the specificity of clostripain from clostridium histolyticum. mapping the s' subsites via acyl transfer to amino acid amides and peptides.the s' subsite specificity of clostripain from clostridium histolyticum was investigated by acyl transfer to libraries of amino acid amides, ala-xaa dipeptides, proline derivatives and pentapeptides using n alpha-benzoyl-l-arginine ethyl ester as acyl donor. a pentapeptide library consisting of 29 pentapeptides with general structure xaa-ala-ala-ala-gly, ala-xaa-ala-ala-gly and ala-ala-xaa-ala-gly, where xaa represents gly, ala, pro, leu, phe, asp, glu, arg and lys, was prepared by solid-phase s ...19948055964
[interaction of collagenases with certain peptide substrates and inhibitors].interactions of collagenases i and ii (clostridiopeptidases) from clostridium histolyticum with hexapeptide substrates in which some l-proline residues are replaced by their d-analogues, as well as with the tripeptide chloromethyl ketone z-gly-pro-gly-ch2cl were studied. a role of stereochemistry of the amino acid residues in the substrate was established and differences between the collagenases, with regard to their specific requirements to substrates, were revealed. the tripeptide chloromethyl ...19948166757
collagen degradation by three clostridium histolyticum collagenase fractions with different substrate specificities. 19948171590
cloning and nucleotide sequence analysis of the colh gene from clostridium histolyticum encoding a collagenase and a gelatinase.the colh gene encoding a collagenase was cloned from clostridium histolyticum jcm 1403. nucleotide sequencing showed a major open reading frame encoding a 116-kda protein of 1,021 amino acid residues. the deduced amino acid sequence contains a putative signal sequence and a zinc metalloprotease consensus sequence, hexxh. a 116-kda collagenase and a 98-kda gelatinase were copurified from culture supernatants of c. histolyticum. while the former degraded both native and denatured collagen, the lat ...19947961400
cells of different tissues for in vitro and in vivo studies in toxicology: compilation of isolation methods.an advantage of using freshly isolated intact cells of different organs in toxicology is that they reflect more closely the in vivo situation than do long-term cultures. in vitro, primary cells provide the possibility of determining cell-specific xenobiotic metabolism, in the absence of artificial extracellular activation systems, which may result in cytotoxic and genotoxic effects. after in vivo exposure of animals to xenobiotics, isolated primary cells can be studied to elucidate toxicokinetic ...199420693101
the heterodimeric protease clostripain from clostridium histolyticum is encoded by a single gene.clostripain (ec 3.4.22.8) is a heterodimeric cysteine endopeptidase with strict specificity for arg-xaa peptidyl bonds. it is secreted by clostridium histolyticum strains. for the first time we present evidence that both polypeptide chains of native clostripain are encoded by a single gene. dna sequencing of two overlapping genomic dna fragments revealed a single open reading frame (orf) of 1581 nucleotides encoding a polypeptide of 526 amino acid residues. the orf is preceded by canonical trans ...19938341259
synthesis of n alpha-[3h]acetyl-l-lysine chloromethyl ketone and its use in the fluorographic detection of proteases.tritiated n alpha-acetyl-l-lysine chloromethyl ketone (alck) was synthesized on a laboratory scale for use as an active-site-directed affinity label in the fluorographic detection of proteases after sodium dodecyl sulfate-polyacrylamide gel electrophoresis (sds-page). the synthesis involved acetylation of n epsilon-benzyloxycarbonyl-l-lysine chloromethyl ketone with [3h]acetic anhydride just before the removal of the benzyloxycarbonyl group. by this method, [3h]alck with a specific activity of 2 ...19938250226
both medullasin and human leukocyte elastase are essentially devoid of elastinolytic activity.elastinolytic activity of medullasin was investigated precisely and compared with that of human leukocyte elastase, because the structure of medullasin is quite similar to that of human neutrophil elastase, which was reported to have elastinolytic activity. when elastinolytic activity of medullasin and human leukocyte elastase was determined by employing unstained elastin fibers and measuring the increase in 280-nm absorbance of the supernatant, elastinolytic activity amounting to several percen ...19938407864
the collagen shield as a collagenase inhibitor and clinical indicator of collagenase activity on the ocular surface.collagen shields applied to the corneas of patients with bacterial keratitis degrade rapidly, often within a few hours. once treatment brings the infection under control, subsequently applied collagen shields degrade more slowly. in vitro models were established to evaluate the significance of these observations. twenty-four and 72-hour collagen shields were incubated with collagenase from clostridium histolyticum. the in vitro rate of digestion of the shields was directly proportional to the co ...19921313747
inhibition of collagenase by aranciamycin and aranciamycin derivatives.aranciamycin (1), an anthracycline antibiotic, was found to be an inhibitor of clostridium histolyticum collagenase, with an ic50 = 3.7 x 10(-7) m. elastase and trypsin were not inhibited at concentrations less than or equal to 10(-5) m. a number of aranciamycin derivatives 2-13 were prepared and tested for collagenase inhibition. while loss of activity was found for derivatives modified in the sugar ring or rings b and d of the aglycone, increased potency was found when the tertiary alcohol at ...19921322986
an analysis of the role of collagenase and protease in the enzymatic dissociation of the rat pancreas for islet isolation.crude clostridium histolyticum collagenase is widely used for the enzymatic degradation of pancreatic extracellular matrix in order to isolate the islets of langerhans. the variable enzymatic composition of crude collagenases is a critical issue which contributes to the poor reproducibility of islet isolation procedures. in this study, the separate contributions of collagenase and protease to the islet isolation process were analysed by testing various combinations of purified collagenase and pu ...19921324862
identification of clostridium histolyticum collagenase hyperreactive sites in type i, ii, and iii collagens: lack of correlation with local triple helical stability.the class i and ii clostridium histolyticum collagenases (chc) have been used to identify hyperreactive sites in rat type i, bovine type ii, and human type iii collagens. the class i chc attack both collagens at loci concentrated in the n-terminal half of these collagens starting with the site closest to the n-terminus. the class ii chc initiate collagenolysis by attacking both collagens in the interior to produce a mixture of c-terminal 62,000 and a n-terminal 36,000 fragments. both fragments a ...19921325154
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