Showing papers on "Chitinase published in 1991"
TL;DR: Transgenic tobacco seedlings constitutively expressing a bean chitinase gene under control of the cauliflower mosaic virus 35S promoter showed an increased ability to survive in soil infested with the fungal pathogen Rhizoctonia solani and delayed development of disease symptoms.
Abstract: The production of enzymes capable of degrading the cell walls of invading phytopathogenic fungi is an important component of the defense response of plants. The timing of this natural host defense mechanism was modified to produce fungal-resistant plants. Transgenic tobacco seedlings constitutively expressing a bean chitinase gene under control of the cauliflower mosaic virus 35S promoter showed an increased ability to survive in soil infested with the fungal pathogen Rhizoctonia solani and delayed development of disease symptoms.
1,025 citations
TL;DR: Three proteins from barley (Hordeum vulgare L.) seeds which synergistically inhibit the growth of fungi measured in a microtiter well assay are purified and their biological roles and potential use in genetic engineering studies are discussed.
611 citations
TL;DR: Analysis of the derived amino acid sequence suggests that the protein contains four domains: a signal sequence, a catalytic domain, a serine/threonine-rich region, and a carboxyl-terminal domain with high binding affinity for chitin.
597 citations
TL;DR: Results demonstrate that the C-terminal extension of tobacco chitinase A is necessary and sufficient for the vacuolar localization of chit inases and, therefore, that it comprises a targeting signal for plant vacuoles.
Abstract: Tobacco contains different isoforms of chitinase (EC 3.2.1.14), a hydrolase thought to be involved in the defense against pathogens. Deduced amino acid sequences for putatively vacuolar, basic chitinases differ from the homologous extracellular, acidic isoforms by the presence of a C-terminal extension. To examine the role of this C-terminal extension in protein sorting, Nicotiana silvestris plants were stably transformed with chimeric genes coding for tobacco basic chitinase A with and without the seven C-terminal amino acids. In plants expressing unmodified chitinase A, the enzyme activity was low in the intercellular wash fluid but high in protoplasts and isolated vacuoles. In contrast, in plants expressing mutant chitinase lacking the C terminus, the activity was high in the intercellular wash fluid but low in protoplasts. N. silvestris plants were also transformed with similar constructions coding for a structurally unrelated, extracellular cucumber chitinase. In plants expressing unmodified cucumber chitinase, its activity was present in the intercellular wash fluid and absent from protoplasts. In plants expressing cucumber chitinase with the C-terminal extension from tobacco chitinase A, activity was low in intercellular wash fluids but high in protoplasts and vacuoles. These results demonstrate that the C-terminal extension of tobacco chitinase A is necessary and sufficient for the vacuolar localization of chitinases and, therefore, that it comprises a targeting signal for plant vacuoles.
354 citations
TL;DR: In several biochemical tests with culture filtrates of P. stutzeri YPL-1 and in mutational analyses of antifungal activities of reinforced or defective mutants, it is found that the anti-F.
Abstract: An actively antagonistic bacterium that could be used as a biocontrol agent against Fusarium solani, which causes root rots with considerable losses in many important crops, was isolated from a ginseng rhizosphere and identified as a strain of Pseudomonas stutzeri. In several biochemical tests with culture filtrates of P. stutzeri YPL-1 and in mutational analyses of antifungal activities of reinforced or defective mutants, we found that the anti-F. solani mechanism of the bacterium may involve a lytic enzyme rather than a toxic substance or antibiotic. P. stutzeri YPL-1 produced extracellular chitinase and laminarinase when grown on different polymers such as chitin, laminarin, or F. solani mycelium. These lytic extracellular enzymes markedly inhibited mycelial growth rather than spore germination and also caused lysis of F. solani mycelia and germ tubes. Scanning electron microscopy revealed degradation of the F. solani mycelium. Abnormal hyphal swelling and retreating were caused by the lysing agents from P. stutzeri YPL-1, and a penetration hole was formed on the hyphae in the region of interaction with the bacterium; the walls of this region were rapidly lysed, causing leakage of protoplasm. Genetically bred P. stutzeri YPL-1 was obtained by transformation of the bacterium with a broad-host-range vector, pKT230. Also, the best conditions for the transformation were investigated.
267 citations
Patent•
22 May 1991TL;DR: In this paper, a novel chitinase gene and its associated regulatory region from a monocotyledon plant was described, and the gene was shown to have a significant effect on the gene expression.
Abstract: Novel chitinase gene, and its associated regulatory region, from a monocotyledon plant is described.
235 citations
TL;DR: It is shown that the peritrophic membrane is digested by Serratia marcescens chitinase (EC 3.2.1.14), leading to the release of N-acetylglucosamine and fragmentation of the membrane and the presence of a malaria parasite chit inase that digests 4-methylumbelliferyl chitotriose.
Abstract: Malaria parasites (ookinetes) appear to digest the peritrophic membrane in the mosquito midgut during penetration. Previous studies demonstrated that lectins specific for N-acetylglucosamine bind to the peritrophic membrane and proposed that the membrane contains chitin [Rudin, W. & Hecker, H. (1989) Parasitol. Res. 75, 268-279]. In the present study, we show that the peritrophic membrane is digested by Serratia marcescens chitinase (EC 3.2.1.14), leading to the release of N-acetylglucosamine and fragmentation of the membrane. We also report the presence of a malaria parasite chitinase that digests 4-methylumbelliferyl chitotriose. The enzyme is not detectable until 15 hr after zygote formation, the time required for maturation of the parasite from a zygote to an ookinete, the invasive form of the parasite. At 20 hr, the enzyme begins to appear in the culture supernatant. The chitinase extracted from the parasite and found in the culture supernatant consists of a major band and two minor bands of activity on native polyacrylamide gel electrophoresis. The presence of chitin in the peritrophic membrane, the disruption of the peritrophic membrane during invasion, and the presence of chitinase in ookinetes suggest that the chitinase in ookinetes is used in the penetration of the peritrophic membrane.
224 citations
TL;DR: High levels of chitInase in transformants did not substantially increase resistance to the chitin-containing fungus Cercospora nicotiana, which causes Frog Eye disease, and class I chit inase does not appear to be the limiting factor in the defense reaction to this pathogen.
Abstract: Endochitinases (E.C. 3.2.14, chitinase) are believed to be important in the biochemical defense of plants against chitin-containing fungal pathogens. We introduced a gene for class I (basic) tobacco chitinase regulated by Cauliflower Mosaic Virus 35S-RNA expression signals into Nicotiana sylvestris. The gene was expressed to give mature, enzymatically active chitinase targeted to the intracellular compartment of leaves. Most transformants accumulated extremely high levels of chitinase-up to 120-fold that of non-transformed plants in comparable tissues. Unexpectedly, some transformants exhibited chitinase levels lower than in non-transformed plants suggesting that the transgene inhibited expression of the homologous host gene. Progeny tests indicate this effect is not permanent. High levels of chitinase in transformants did not substantially increase resistance to the chitin-containing fungus Cercospora nicotiana, which causes Frog Eye disease. Therefore class I chitinase does not appear to be the limiting factor in the defense reaction to this pathogen.
214 citations
01 Jan 1991
TL;DR: 2,6-dichloro-isonicotinic acid and its ester derivative induce local and systemic resistance in cucumber against C. lagenarium as well as other pathogens.
Abstract: 2,6-dichloro-isonicotinic acid (CGA 41396) and its ester derivative (CGA 41397) induce local and systemic resistance in cucumber against C. lagenarium as well as other pathogens. These compounds have no direct fungicidal effet comparable to standard fungicides and extracts from treated plants do not show the presence of fungitoxic metabolites. In addition both compounds modify the physiology of the host plant by inducing chitinase. Thus CGA 41396 and 41397 could be considered as novel inducers of resistance.
196 citations
TL;DR: A procedure to detect chitinase and β-1,3-glucanase isozymes and protein patterns after a single separation using native polyacrylamide gel electrophoresis (PAGE) or isoelectrofocusing (IEF) is described.
Abstract: A procedure to detect chitinase and beta-1,3-glucanase isozymes and protein patterns after a single separation using native polyacrylamide gel electrophoresis (PAGE) or isoelectrofocusing (IEF) is described. After electrophoresis or isoelectrofocusing, an overlay gel containing glycol chitin as substrate for chitinase was incubated in close contact with the resolving gel. Chitinase isozymes were revealed by UV illumination after staining the overlay gel with fluorescent brightener 28. The resolving gel was then incubated with laminarin, and beta-1,3-glucanase isozymes were detected by using 2,3,5-triphenyltetrazolium chloride. The resolving gel with beta-1,3-glucanase bands was stained with Coomassie Brilliant Blue R 250 to reveal protein patterns. The isozymes were quantified by using native PAGE, and their pIs were estimated by IEF
188 citations
TL;DR: The results indicate that the homologous maize grain bifunctional inhibitor of insect α‐amylase and trypsin is very similar to or identical with maize zeamatin, which was proposed to have permeabilizing activity towards fungal membranes.
TL;DR: Analysis of a series of 5[prime] deletions of the acidic chitinase promoter in Arabidopsis indicated that the proximal 192 bp from the transcription initiation site was sufficient to establish both the constitutive and induced pattern of expression.
Abstract: Expression of the Arabidopsis acidic chitinase promoter was investigated during plant development and in response to inoculation with fungal pathogens. A chimeric gene composed of 1129 bp of 5[prime] upstream sequence from the acidic chitinase gene was fused to the [beta]-glucuronidase (GUS) coding region and used to transform Arabidopsis and tomato. Promoter activity was monitored by histochemical and quantitative assays of GUS activity. In healthy transgenic plants, the acidic chitinase promoter activity was restricted to roots, leaf vascular tissue, hydathodes, guard cells, and anthers, whereas GUS expression was induced in mesophyll cells surrounding lesions caused by Rhizoctonia solani infection of transgenic Arabidopsis. In transgenic tomato plants, GUS expression was induced around necrotic lesions caused by Alternaria solani and Phytophthora infestans. Expression of the acidic chitinase promoter-GUS transgene was weakly induced by infiltrating leaves with salicylic acid. Analysis of a series of 5[prime] deletions of the acidic chitinase promoter in Arabidopsis indicated that the proximal 192 bp from the transcription initiation site was sufficient to establish both the constitutive and induced pattern of expression. Elements further upstream were involved in quantitative expression of the gene. The location of a negative regulatory element was indicated between -384 and -590 and positive regulatory elements between -1129 and -590.
TL;DR: A chitinolytic isolate of Aeromonas caviae was isolated from roots of healthy bean plants grown in soil artificially infested with Sclerotium rolfsii and was shown to act in an exo-splitting manner.
Abstract: A chitinolytic isolate of Aeromonas caviae was isolated from roots of healthy bean plants grown in soil artificially infested with Sclerotium rolfsii. Under greenhouse conditions, the bacterium controlled Rhizoctonia solani and Fusarium oxysporum f.sp. vasinfectum in cotton (78 and 57% disease reduction, respectively) and S. rolfsii in beans (60% disease reduction). Seed coating was the most effective application method for controlling R. solani in cotton. There was no evidence of inhibition of the fungal pathogens by A. caviae. A caviae partially lysed live mycelium of R. solani, S. rolfsii and F. oxysporum f.sp. vasinfectum when their mycelium served as a sole carbon source in liquid medium. A high chitinolytic activity was found when colloidal chitin was used as a sole carbon source, with an optimum pH between 6.0–7.0. No β-3-glucanase was produced by the bacterium. After partial purification of the enzyme by affinity adsorption to colloidal chitin, three bands appear in sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS PAGE). One strong band with a molecular weight of ca. 80 kDa, and two weak bands with molecular weights of 48 and 59 kDa. Using the chromogenic substrate pNp-chitobiose, the partially purified chitinase from A. caviae was shown to act in an exo-splitting manner.
TL;DR: The primary structure of hevamine, an enzyme with lysozyme/chitinase activity from Hevea brasiliensis latex, has been determined predominantly with conventional non-automatic methods and the positions of three disulfide bridges have been determined.
Abstract: The primary structure of hevamine, an enzyme with lysozyme/chitinase activity from Hevea brasiliensis latex, has been determined predominantly with conventional non-automatic methods. The positions of three disulfide bridges have been determined. The sequence has about 60% identity with that of a chitinase from cucumber and 95% with the N-terminal sequence of the lysozyme/chitinase of Parthenocissus quinquefolia. The half-cystine residues in hevein and cucumber chitinase are located at identical positions. Hevamine is a basic protein from the lutoids (vacuoles) of rubber latex and may have a role in plugging the latex vessels and cessation of latex flow. The differences in cellular location, charge properties and sequence between hevamine and cucumber chitinase are similar to those between class I and class II chitinases from tobacco and other plant species.
TL;DR: The production of chitinase by Trichoderma species is of interest in relation to their use in biocontrol and as a source of mycolytic enzymes, and the mode of ch itinase synthesis in this fungus is discussed.
Abstract: Summary: The production of chitinase by Trichoderma species is of interest in relation to their use in biocontrol and as a source of mycolytic enzymes. Fourteen isolates of the genus were screened to identify the most effective producer of chitinase. The best strain for chitinase was Trichoderma harzianum 39.1, and this was selected for study of the regulation of enzyme synthesis. Washed mycelium of T. harzianum 39.1 was incubated with a range of carbon sources. Chitinase synthesis was induced on chitin-containing medium, but repressed by glucose and N-acetylglucosamine. Production of the enzyme was optimal at a chitin concentration of 0·5%, at 28 °C, pH 6·0 and was independent of the age of the mycelium. The synthesis of chitinase was blocked by both 8-hydroxyquinoline and cycloheximide, inhibitors of RNA and protein synthesis, respectively. The mode of chitinase synthesis in this fungus is discussed.
TL;DR: The complete nucleotide sequence of the rice chitinase RCH10 gene was determined, and shown to contain an open reading frame with no introns, encoding a polypeptide of 336 amino acids, which is involved in inducible defenses of plants.
Abstract: Chitinase, which catalyzes the hydrolysis of the beta-1,4-N-acetyl-D-glucosamine linkages of the fungal cell wall polymer chitin, is involved in inducible defenses of plants. A basic chitinase genomic sequence was isolated from a rice (Oryza sativa L.) genomic library using a bean chitinase gene fragment as a probe. The complete nucleotide sequence of the rice chitinase RCH10 gene was determined, and shown to contain an open reading frame with no introns, encoding a polypeptide of 336 amino acids. This polypeptide consists of a 21 amino acid signal peptide, a hevein domain, and a chitinase catalytic domain. The RCH10 gene has 63% identity at the nucleotide level and 75% identity at the amino acid level with chitinase genes from dicotyledonous plants such as bean, potato, and tobacco. A gene fusion of trpE and the coding region of RCH10 expressed in Escherichia coli gave a product that reacted with antiserum to bean chitinase, confirming the identity of RCH10 as a rice chitinase gene. Primer extension analysis identified two transcription start sites 53 bp and 55 bp upstream from the translation initiation codon. The 5' flanking region contains TATA and CAAT boxes, and the 3' region contains an AATAA polyadenylation signal. Southern blot hybridization indicated that there is a family of chitinase genes in the rice genome. Northern blot analysis showed that the RCH10 chitinase gene is induced in suspension cultured cells by a fungal cell wall elicitor. Rice chitinase transcripts accumulate to a high level in roots, but only low levels are found in stem and leaf tissue.
TL;DR: Cloned genes were cloned from S. lividans TK64 into the multicopy plasmid pIJ702 and their expression monitored in their natural host by measuring increases in chitinase productivity, and significant differences were observed between chit inases A, B, and C in terms of optimum pH for activity and mode of digestion of substrates.
Abstract: Summary: In order to study the genetic control of chitinolytic activity in Streptomyces, chitinase genes were cloned from S. lividans TK64 into the multicopy plasmid pIJ702 and their expression monitored in their natural host by measuring increases in chitinase productivity. Four independent clones were obtained, and the plasmids named pEMJ1, pEMJ5, pEMJ7 and pEMJ8. Restriction endonuclease digestion showed that although two of the plasmids (pEMJ7 and pEMJ8) shared a common DNA fragment, there were no substantial similarities between the inserts of plasmids pEMJ1, pEMJ5 and pEMJ7. This was confirmed by DNA-DNA hybridization studies. Four chitinases (A, B, C, and D) were identified, with molecular masses of 36, 46, 65, and 41 kDa, respectively. Production of chitinases A and B was specified by the plasmids pEMJ1 and pEMJ5, respectively. Genes for the other two chitinases (C and D) were carried by plasmid pEMJ7. Although significant differences were observed between chitinases A, B, and C in terms of optimum pH for activity and mode of digestion of substrates, chitinases C and D were very similar in these respects. Cloned genes were also expressed in S. coelicolor M130 and in Escherichia coli.
TL;DR: It is found that chitinase and A-acetylglucosaminidase are secreted by cultured L. major promastigotes, but not by sandfly guts, Hence lysis of the chit in layer of the peritrophic membrane could be catalysed by these enzymes of the parasites.
Abstract: Leishmania major parasites ingested with host blood by the sandfly Phlebotomus papatasi multiply confined within the peritrophic membrane. This membrane consists of a chitin framework and a protein carbohydrate matrix and it is secreted around the food by the insect midgut. Histological sections of infected flies show lysis of the chitin layer in the anterior region of the peritrophic membrane that permits the essential forward migration of a concentrated mass of parasites. Both the location and the nature of this disintegration are specific to infected flies. At a later stage the parasites concentrate in the cardiac valve region and subsequently this segment of the fore gut loses its cuticular lining. We have found that chitinase and N-acetylglucosaminidase are secreted by cultured L. major promastigotes, but not by sandfly guts. Hence lysis of the chitin layer of the peritrophic membrane could be catalysed by these enzymes of the parasites. Activity of both enzymes was also observed in other trypanosomatids, including L. donovani, L. infantum, L. braziliensis, Leptomonas seymouri, Crithidia fasciculata and Trypanosoma lewisi.
TL;DR: Four kinds of thermostable chitinase were isolated from the cell-free culture broth of Bacillus licheniformis X-7u by successive column chromatographies on Butyl-Toyopearl, Q-Sepharose, and Sephacryl S-200, showing remarkable heat stability.
TL;DR: The purification and characterization of a basic chitinase from Arabidopsis thaliana (L.) Heynh is reported, which is an effective inhibitor of the growth of Trichoderma reesei in vitro but does not affect thegrowth of several other fungi.
Abstract: Plants exhibit an altered pattern of protein synthesis in response to pathogen invasion and abiotic stress. One of these ;pathogenesis-related' proteins has been identified as chitinase, which is capable of inhibiting fungal growth in vitro. This observation has led to the suggestion that the in vivo role of chitinases is to protect plants against fungal invasion. Here, we report the purification and characterization of a basic chitinase from Arabidopsis thaliana (L.) Heynh. Columbia wild type. The purified enzyme has a molecular mass of approximately 32 kilodaltons as determined by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate, and an apparent pl of approximately 8.7 as determined by isoelectric focusing. The purified protein is an effective inhibitor of the growth of Trichoderma reesei in vitro but does not affect the growth of several other fungi. Amino acid composition analysis of the intact protein as well as amino acid composition analysis and automatic Edman degradation of isolated tryptic fragments of the enzyme indicate that it may be identical to the product of a chitinase gene isolated from an Arabidopsis genomic library (Samac DA, Hironaka CM, Yallaly PE, Shah DM [1990] Plant Physiol 93: 907-914).
TL;DR: The latex of the commercial rubber tree was fractionated by ultracentrifugation into a top layer of rubber particles, a cleared cytoplasm, and a pellet that contains primarily specialized vacuoles known as lutoids, suggesting that laticifers serve a defensive role in the plant.
Abstract: The latex of the commercial rubber tree, Hevea brasiliensis, was fractionated by ultracentrifugation as described by G. F. J. Moir ([1959] Nature 184: 1626-1628) into a top layer of rubber particles, a cleared cytoplasm, and a pellet that contains primarily specialized vacuoles known as lutoids. The proteins in each fraction were resolved by two-dimensional gel electrophoresis. Both the pellet fraction and cleared cytoplasm contained large amounts of relatively few proteins, suggesting that laticifers serve a very specialized function in the plant. More than 75% of the total soluble protein in latex was found in the pellet fraction. Twenty-five percent of the protein in the pellet was identified as chitinases/lysozymes, which are capable of degrading the chitin component of fungal cell walls and the peptidoglycan component of bacterial cell walls. Both the chitinase and lysozyme activities were localized exclusively in the pellet or lutoid fraction. The chitinases/lysozymes were resolved into acidic and basic classes of proteins and further purified. An acidic protein (molecular mass 25.5 kD) represented 20% of the chitinase activity in latex; this protein lacked the low level of lysozyme activity that is associated with many plant chitinases. Six basic proteins, having both chitinase and lysozyme activities in various ratios and molecular mass of 27.5 or 26 kD, were resolved. Two of the basic proteins had very high lysozyme specific activities which were comparable to the specific activities reported for animal lysozymes. Like animal lysozymes, but unlike previously characterized plant chitinases/lysozymes, these basic chitinases/lysozymes were also capable of completely lysing or clearing suspensions of bacterial cell walls. These results suggest that laticifers may serve a defensive role in the plant.
TL;DR: In this article, the mechanism of action of chitinolytic enzymes is discussed, and the chitinase fractions eluted from a sephadex column had activity against chitosan and chitotriose.
TL;DR: An hypothesis is presented for the function of the complex chitinolytic system of the fungal hypha in branching and, possibly, also in apical growth.
Abstract: SUMMARY: Enzymological evidence has been sought for the purported involvement of chitinolysis in vegetative growth of filamentous fungi. A procedure has been developed for the production of fast growing and morphologically homogeneous exponential phase mycelium of the non-septate dimorphic zygomycete Mucor rouxii. A partially purified extract of this material has been subjected to gel-permeation chromatography and the chitinolytic activity of eluate fractions has been assessed using colloidal and nascent chitin and 3,4-dinitrophenyl tetra-N-acetylchitotetraoside [3,4-DNP-(GlcNAc)4] as substrates. Exponentially growing (td = 1·1 h) mycelium consisting of single short-branched hyphae contains at least seven chitinases. The two particulate ones have not been studied in detail. The soluble chitinases hydrolyse (pseudo)chito-oligomers by random cleavage of internal β-1,4-bonds (and not by processing) and have a minimum chain-length requirement of n = 4. They are clearly distinct from β-N-acetylglucosaminidase (β-GlcNAc'ase) with respect to their chromatographic behaviour, substrate chain-length specificity, inhibition by chitobionolactone oxime (K
1 = 175 μM), and non-inhibition by the specific β-GlcNAc'ase inhibitor N-acetylglucosaminono-1,5-lactone oxime. Their pH optima are similar (6·5-7·0), and all can hydrolyse 3,4-DNP-(GlcNAc)4 as well as nascent chitin. With respect to their charge, response to protease treatment, behaviour upon gel-permeation chromatography and ability to use colloidal chitin as a substrate, the soluble chitinases do, however, represent two distinct groups. Type A chitinases are acidic, display partial latency, show an unusual affinity to dextran gel and act weakly on colloidal chitin. Type B chitinases are basic (or neutral) and non-zymogenic, do not behave anomalously upon gel filtration and can degrade preformed chitin. An hypothesis is presented for the function of the complex chitinolytic system of the fungal hypha in branching and, possibly, also in apical growth.
TL;DR: Southern blot analysis of bean genomic DNA revealed that PR4 chitinase is encoded by a single gene, and shows some homology to the basic isoform from the same plant.
Abstract: The amino acid sequences of peptides generated by trypsin and chymotrypsin digestions of the acidic PR4 chitinase from bean were determined. Oligonucleotide primers derived from this sequence were used to synthesize a PR4 chitinase-specific probe by PCR-amplification. This probe allowed the isolation of cDNA clones encoding PR4 chitinase that have been sequenced. This acidic and extracellular chitinase shows some homology to the basic isoform from the same plant, and differs from other known acidic chitinases by the presence of an amino-terminal cysteine-rich domain. Southern blot analysis of bean genomic DNA revealed that PR4 chitinase is encoded by a single gene.
TL;DR: The enzymatic hydrolysis of native and pretreated chitin by the culture filtrate of Myrothecium verrucaria NCIM 903 indicated that the swelling of the ordered structure results in efficient hydrolyzing.
Abstract: The enzymatic hydrolysis of native and pretreated chitin by the culture filtrate of Myrothecium verrucaria NCIM 903 was studied. Also, factors which influence the enzymatic hydrolysis such as pH, temperature, enzyme and substrate concentration and enzyme adsorption characteristics (n-value) were studied. Chitin hydrolysate was also used as a substrate for Single Cell Protein (SCP) production using Saccharomyces cerevisiae NCIM 3052. With M. verrucaria chitinase complex, native and acid swollen chitin were hydrolyzed at pH 5.0 and 40°C, 12.7% and 39.6% respectively. The n values which is a measure of adsorption characteristics of an enzyme were 0.4 and 0.63 for native and acid swollen chitin, respectively. This indicates that the swelling of the ordered structure results in efficient hydrolysis. As the end-product of hydrolysis of chitin was mainly N-acetyl-D-glucosamine, its further utilization as a substrate for SCP production was investigated. A biomass of 9.5g/l with a growth yield of 0.27g/g of substrate utilized was obtained. The total protein and nucleic acid content of the biomass was 61% and 3.1%, respectively.
TL;DR: Rice chitinase mRNA levels increased after treating leaves and suspension cultured cells with ethylene or stress-inducings compounds, and DNA blot hybridization analysis suggested that chit inase was encoded by a multigene family of four to six genes.
TL;DR: Isozyme patterns of β-1,3-glucanase and chitinase in all resistant tissues are typical of those of tissues systemically protected by either stem injection with Peronospora tabacina or foliar inoculation with TMV.
TL;DR: The results suggest that secretion of chitinase and β-1,3-glucanase from the embryogenic cell suspensions of barley corresponds to accumulation of the same enzymes in barley grain.
TL;DR: Transmission electron microscopy of thin sections of cells and walls showed that mannoproteins and chitin are evenly distributed throughout the entire cell wall structure.
Abstract: Different techniques released from the wall of Candida albicans mycelial cells high molecular weight mannoprotein materials with different levels of complexity. SDS solubilized among others one protein of 180 kDa which reacted with a monoclonal antibody (MAb) specific of a O-glycosylated protein secreted by regenerating mycelial protoplasts [Elorza et al. (1989) Biochem Biophys Res Commun 162:1118-1125]. Zymolyase, chitinase and beta-mercaptoethanol, released different types of high molecular highly polydisperse mannoprotein materials (greater than 180 kDa) that also reacted with the same MAb. These materials had N-glycosidically linked sugar chains, in addition to the O-glycosidically bonded sugars, as their molecular masses were significantly reduced by Endo H digestion. Besides, the specific materials released by either zymolyase or chitinase seemed to be the same throughout the process of germ tube formation. Transmission electron microscopy of thin sections of cells and walls showed that mannoproteins and chitin are evenly distributed throughout the entire cell wall structure.
TL;DR: Three of new allosamidins were isolated as yeast chitinase inhibitors from the mycelium of Streptomyces sp.
Abstract: Three of new allosamidins, termed glucoallosamidins A (5), B (6) and methyl-N-demethyl-allosamidin (4), were isolated as yeast chitinase inhibitors from the mycelium of Streptomyces sp. SA-684.