molecular cloning of the imidazoleglycerolphosphate dehydratase gene of trichoderma harzianum by genetic complementation in saccharomyces cerevisiae using a direct expression vector.the trichoderma harzianum imidazoleglycerolphosphate dehydratase gene (igh) has been isolated by complementation of a saccharomyces cerevisiae his3 mutant using a direct expression vector. this escherichia coli-yeast shuttle vector was developed to allow efficient cloning and expression of cdna libraries. the cdna is 627 nucleotides long and codes for a protein of 209 amino acids with an apparent molecular mass of 22,466 daltons. the predicted protein sequence showed 63.6%, 58.7%, and 38.4% iden ...19921406594
changes in selected enzyme activities during growth of pure and mixed cultures of the white-rot decay fungus trametes versicolor and the potential biocontrol fungus trichoderma harzianum.two filamentous fungi, the white-rot fungus trametes versicolor and the soil fungus and potential biocontrol organism trichoderma harzianum, have been grown in pure and mixed cultures on low-n (0.4 mm) and high-n (4 mm) defined synthetic media to determine the activities of selected wood-degrading enzymes such as cellobiase, cellulase, laccase, and peroxidases. growth characteristics and enzyme activities were examined for potential correlations. such correlations would allow the use of simple e ...19921611557
antifungal activity of chitin-binding pr-4 type proteins from barley grain and stressed leaf.antifungal activity in vitro has been associated with barley leaf and grain proteins which are homologous with pathogenesis related proteins of type 4 (pr-4) from tobacco and tomato and with c terminal domains of potato win and hevea hevein precursor proteins. one protein (pi approximately 9.3, m(r) approximately 13.7 kda) from barley grain and two very similar proteins from leaves infected with erysiphe graminis were isolated by chitin affinity chromatography, but none of the proteins showed ch ...19921644196
biomimics of fungal cell-cell recognition by use of lectin-coated nylon fibers.when the mycoparasitic, biocontrol fungus trichoderma harzianum was allowed to grow on nylon fibers treated with concanavalin a or sclerotium rolfsii lectin, it coiled around the nylon fibers and produced hooks in a pattern similar to that observed with the real host hyphae. the incidence of interaction between t. harzianum and s. rolfsii lectin-treated fibers was significantly higher than that of the controls (untreated or blocked activated fibers). these findings provide direct evidence for th ...19921732197
effect of ultraviolet-induced mutants of trichoderma harzianum with altered antibiotic production on selected pathogens in vitro.mutants of trichoderma harzianum with altered antibiotic production were isolated using ultraviolet light mutagenesis. these included strains whose activity in a fusarium oxysporum spore germination assay was greater than twice that of the parental strain and one that had no detectable antifungal activity. characterisation of extracellular metabolites of these strains using thin-layer chromatography and gas-liquid chromatography showed that the strains with high activity produced only elevated l ...19911954580
[comparative study of the effect of l-lysine-l-oxidase from trichoderma harzianum rifai and trichoderma viride on nucleic acid synthesis in human tumor cells in vitro].l-lysine-alpha-oxidase, a new fungal enzyme catalyzing oxidative deamination of l-lysine, exerts an inhibitory effect on dna, rna and protein synthesis in human cells of carcinoma ovarius (caov) in vitro.19863708146
fungi associated with urea-formaldehyde foam insulation in canada.sixty-eight fungal taxa were identified from samples of urea-formaldehyde foam insulation taken from canadian residences. mesophilic taxa were predominant, with penicillium spp., trichoderma harzianum and paecilomyces variotii observed most frequently. extensive or conspicuous growth also was seen for hormoconis resinae, stachybotrys chartarum and trichoderma viride in some samples. the potential for these fungi to have contributed to the adverse health effects reported in some homes containing ...19873627222
[cytostatic effect of l-lysine-alpha-oxidase from trichoderma harzianum rifai and trichoderma viride].l-lysine-alpha-oxidase, a new fungal enzyme catalyzing oxidative l-lysine deamination, was shown to have an inhibitory effect on the in vitro synthesis of dna, rna and proteins in human carcinoma ovarian (caov) cells.19873567343
mycoflora and vitamin content of sun-dried food condiments in nigeria.the fungi most frequently isolated (of 20-100% incidence) from fresh okra, pepper fruits and melon seeds are botryodiplodia theobromae, rhizopus stolonifer, trichoderma harzianum, mucor mucedo and fusarium oxysporum. the major mycoflora of the fruits which had been sun-dried for twenty days are comprised of aspergillus spp and penicillium spp which initially had formed the minor components (of less than 20% incidence) of the colonising population. the effect of sun-drying on the fruits was a sta ...19873507682
purification and characterization of an endo-beta-1,6-glucanase from trichoderma harzianum that is related to its mycoparasitism.the enzymes from trichoderma species that degrade fungal cell walls have been suggested to play an important role in mycoparasitic action against fungal plant pathogens. the mycoparasite trichoderma harzianum produces at least two extracellular beta-1,6-glucanases, among other hydrolases, when it is grown on chitin as the sole carbon source. one of these extracellular enzymes was purified to homogeneity after adsorption to its substrate, pustulan, chromatofocusing, and, finally, gel filtration. ...19957896713
ethanol fermentation of enzymatically hydrolysed leached beet cosette using trichoderma harzianum cellulases and saccharomyces cerevisiae. 19873326098
characterization of ech-42, a trichoderma harzianum endochitinase gene expressed during mycoparasitism.a gene (ech-42; previously named then-42) coding for one of the endochitinases produced by the biocontrol agent trichoderma harzianum imi206040 was cloned and characterized. expression of the cdna clone in escherichia coli resulted in bacteria with chitinase activity. this chitinase has been shown to have lytic activity on botrytis cinerea cell walls in vitro. the ech-42 gene was assigned to a double chromosomal band (chromosome v or vi) upon electrophoretic separation and southern analysis of t ...19947971981
a convenient procedure for rapid release of protoplasts from ustilago maydis.filtrates from cultures of trichoderma harzianum, grown on a liquid mineral salts medium containing vitamin and trace element supplements, 0.5 g/l glucose and 2 g/l of dried residue of ethanol-extracted commercial mushrooms (agaricus brunnescens), are a good source of enzymes for the release of protoplasts from the sporidia of ustilago maydis. when concentrated 50-fold by (nh4)2so4 precipitation, the enzymes liberated 95% of the protoplasts from the sporidia within 40 min.19883273191
a newly isolated lectin from the plant pathogenic fungus sclerotium rolfsii: purification, characterization and role in mycoparasitism.a novel lectin was isolated and purified from the culture filtrate of the soilborne plant pathogenic fungus sclerotium rolfsii by anion-exchange chromatography using a deae-sepharose column. the lectin came through the column with the flow-through, whereas all the non-agglutinating proteins present in the crude preparation remained bound to the column until elution in a nacl gradient. sds-page analysis of the agglutinating fraction revealed a single band corresponding to a protein with a molecul ...19948012587
isolation of dna from yeasts.methods are described that allow dna to be prepared from widely different yeasts (candida utilis, saccharomyces cerevisiae, and schizosaccharomyces pombe). the methods are reliably reproducible, and the dna obtained is of appropriate quality for the construction of gene libraries (upper limit of size range consistently 50-150 kbp). in method a, yeast cells are converted into spheroplasts by treatment with a highly purified mixture of enzymes from trichoderma harzianum, the spheroplasts are lysed ...19892729583
[antagonism in vitro among phytopathogenic and saprobic fungi from horticultural soils].two methods were tested in order to determine the existence of in vitro antagonism among saprobic and pathogenic fungi. these microorganisms were the most common isolates from horticultural soils of la plata (buenos aires). trichoderma harzianum; t. koningii and penicillium sp. were antagonistic to all the pathogenic fungi tested, fusarium solani; f. oxysporum; alternaria solani; colletotrichum sp. and sclerotium rolfsii spicaria sp., paecilomyces sp. and chaetomiun sp. were antagonistic only to ...19902287718
differentiation of species and strains among filamentous fungi by dna fingerprinting.we have analyzed 11 strains and clones, representing five species (penicillium janthinellum, p. citrioviridae, p. chrysogenum, aspergillus niger, trichoderma harzianum) and three genera of filamentous fungi, for the presence of hypervariable loci in their genomes by hybridization with simple repeat oligonucleotides and the dna of phage m13. the oligonucleotide probes (ct)8, (gtg)5 and (gaca)4, as well as m13 dna, are informative probes for fingerprinting in all genera and species tested. the pro ...19911907892
mycoflora associated with five species of freshwater leeches.twenty-two species belonging to 11 genera of zoosporic fungi were collected from 10 freshwater sites and from five species of leeches on sesame and hemp seeds, maize grains and pinus pollen grains as baits at 22 degrees c. dictyuchus, achlya, pythium, allomyces and saprolegnia were the most common genera. the highest population of zoosporic fungi was estimated from batracobdelloides tricarinata, the lowest from barbronia assiuti. in addition fifty-three species and 1 variety representing 23 terr ...19911818104
cloning and chromosomal organization of a gene encoding a putative amino-acid permease from saccharomyces cerevisiae.a new member of the yeast amino acid (aa) permease gene family has been cloned, mapped and sequenced. the sequence of the pap1 (putative aa permease 1) gene contains an open reading frame of 566 aa corresponding to a polypeptide with a calculated m(r) of 62,704. its hydropathy profile suggests the presence of 13 membrane-spanning regions and a charged n-terminal domain. it does not resemble hydrophobic signal sequences found in secreted proteins. hence, pap1 encodes a protein with characteristic ...19948200527
isolation and characterization of three chitinases from trichoderma harzianum.three proteins which display chitinase activity were purified from the supernatants of trichoderma harzianum cect 2413 grown in minimal medium supplemented with chitin as the sole carbon source. purification was carried out after protein precipitation with ammonium sulphate, adsorption to colloidal chitin and digestion, and, finally, chromatofocusing. by this procedure, two chitinases of 42 kda (chit42) and 37 kda (chit37) were purified to homogeneity, as judged by sds/page and gel filtration, w ...19921606968
quantitative separation of trichoderma lipid classes on a bonded phase elut aminopropyl columns were used to purify the different lipid classes of trichoderma harzianum and trichoderma viride. this methodology permitted good separation of the fungal lipid classes in less time than traditional techniques. the incorporation of [1 (14)c]linoleic acid into neutral lipids, free fatty acids and phospholipids was quantified for both strains. the fatty acid profile of the different lipid classes of these fungal strains was determined as a function of culture time.19921487513
new structural features of the antigenic extracellular polysaccharides of penicillium and aspergillus species revealed with study the structures of the epitopes of the extracellular polysaccharides from penicillium and aspergillus species, an exo-beta-d-galactofuranosidase was purified from a commercial crude enzyme preparation from trichoderma harzianum. analysis of ring size and linkage position of the galactose residues of the extracellular polysaccharide of penicillium digitatum, before and after enzymatic treatment, was determined by the reductive-cleavage technique. in addition to terminal and beta (1-5)-lin ...19921383191
antagonistic effects of trichoderma harzianum on pythium aphanidermatum causing the damping-off disease of tobacco in nigeria.culture filtrates of trichoderma harzianum rifai have been found to inhibit zoospore germination, germ tube elongation and mycelial growth of pythium aphanidermatum causing the damping-off disease of tobacco in nigeria. further, the invasion of the hyphae of p. aphanidermatum by hyphae of t. harzianum has been demonstrated in mixed cultures of the two fungi. the results of investigations on the role of t. harzianum as an agent of biological control of the damping-off disease in sterilized and u ...19751239662
formation of protoplasts from ustilago maydis.protoplasts of ustilago maydis were obtained by incubating sporidia of the fungus with a combination of helicase and a commercial "onozuka" r-10 enzyme preparation of trichoderma harzianum in the presence of 0.6 m (nh4)2 so4 as an osmotic stabilizer. in the presence of the organic stabilizers sorbitol and sucrose, however, the release of protoplasts was inhibited. combinations of helicase with other lytic enzymes such as cellulase from aspergillus niger, cellulase and hemicellulase from rhizopus ...19761086637
interactions of phytophthora cinnamomi and trichoderma spp. in relation to propagule production in soil cultures at 26 degrees c1.effects of trichoderma harzianum and t. polysporum on chlamydospore production by two isolates of phytophthora cinamomi were determined over a 21-day period in nonsterile, sterilized, and sterilized amended soil. trichoderma was either coinoculated with p. cinnamomi or added to the cultures on day 3 of the incubation period. in nonsterile soil, conversion of mycelial fragments in the p. cinnamomi inoculum to chlamydospores resulted in an initial slight increase in chlamydospore numbers. in cultu ...1977558040
the preparation and chemical composition of fractions from aspergillus fumigatus wall and protoplasts possessing antigenic activity.a detergent-soluble fraction was prepared from the fragmented wall of aspergillus fumigatus mycelium using the non-ionic detergent triton x-100, and a wall-free extract was prepared from the same source in the form of protoplasts, released by a lytic enzyme system from trichoderma harzianum. these extracts were examined by polyacrylamide gel electrophoresis and their detailed chemical composition was established. they were compared with the water-soluble fraction prepared from total mycelium, wh ...1979225408
parallel formation and synergism of hydrolytic enzymes and peptaibol antibiotics, molecular mechanisms involved in the antagonistic action of trichoderma harzianum against phytopathogenic fungi.chitinase, beta-1,3-glucanase, and protease activities were formed when trichoderma harzianum mycelia, grown on glucose as the sole carbon source, were transferred to fresh medium containing cell walls of botrytis cinerea. chitobiohydrolase, endochitinase, and beta-1,3-glucanase activities were immunologically detected in culture supernatants by western blotting (immunoblotting), and the first two were quantified by enzyme-linked immunosorbent assay. under the same conditions, exogenously added ...19947811076
secretion of an enzymatically active trichoderma harzianum endochitinase by saccharomyces cerevisiae.a novel endochitinase agar-plate assay has been developed and used to identify 11 full-length cdnas encoding endochitinase i (enci) from a trichoderma harzianum cdna library by expression in yeast. the 1473-bp chi1 cdna encodes a 424-residue precursor protein including both a signal sequence and a propeptide. the deduced enci amino-acid sequence is homologous to other fungal and bacterial chitinases, and the enzyme cross-reacts with a polyclonal antiserum raised against chitinase a1 from bacillu ...19968598062
cloning and characterization of a chitinase (chit42) cdna from the mycoparasitic fungus trichoderma harzianum.a cdna of trichoderma harzianum (chit42), coding for an endochitinase of 42 kda, has been cloned using synthetic oligonucleotides corresponding to amino-acid sequences of the purified chitinase. the cdna codes for a protein of 423 amino acids. analysis of the n-terminal amino-acid sequence of the chitinase, and comparison with that deduced from the nucleotide sequence, revealed post-translational processing of a putative signal peptide of 22 amino acids and a second peptide of 12 amino acids. th ...19947750151
isolation and characterization of a cdna from trichoderma harzianum p1 encoding a 14-3-3 protein homolog.a full-length cdna close, th1433, (genbank accession no. u24158), was isolated and characterized from the filamentous fungus, trichoderma harzianum. the deduced amino acid (aa) sequence showed an acidic 30-kda protein homologous to the 14-3-3 proteins, a family of putative kinase regulators originally characterized in mammalian brain tissue. the greatest homology, 71% identical aa, was found to bmh1, the corresponding protein from saccharomyces cerevisiae and to the epsilon isoform from sheep br ...19968675020
mycoparasitic species of trichoderma produce lectins.culture filtrates and mycelial extracts of two mycoparasitic trichoderma species were tested for the presence of lectins, by haemagglutination with human and marsupial erythrocytes. in trichoderma viride, haemagglutinating activity was present in both mycelial extracts and culture filtrate. while secreted lectins were only detected after 6 days of growth, the presence of mycelium-associated lectins was first noted in 3-day-old cultures. agglutinating activity was also demonstrated in the myceliu ...19968742357
molecular characterization and heterologous expression of an endo-beta-1,6-glucanase gene from the mycoparasitic fungus trichoderma harzianum.hydrolytic enzymes from the filamentous fungus trichoderma harzianum have been described as critical elements of the mycoparasitic action of trichoderma against fungal plant pathogens. in this report we describe the first genomic and cdna clones encoding a beta-1,6-endoglucanase gene. the deduced protein sequence has limited homology with other beta-glucanases. northern experiments show a marked repression of mrna accumulation by glucose. the protein has been successfully produced in saccharomyc ...19957603444
cell wall synthesis is a major target of mycoparasitic antagonism by trichoderma harzianum.we have investigated the molecular basis for the reported synergism between peptaibols and cell wall hydrolytic enzymes in the antagonism of phytopathogenic fungi by trichoderma harzianum. beta-glucan synthase activity on isolated plasma membranes of botrytis cinerea was inhibited in vitro by the peptaibols trichorzianin ta and tb, and this inhibition was reversed by the addition of phosphatidylcholine. beta-glucan synthesis in vivo, assayed by the incorporation of [2-(3)h]glucose into cell wall ...19968892847
a novel endo-beta-1,3-glucanase, bgn13.1, involved in the mycoparasitism of trichoderma harzianum.the mycoparasitic fungus trichoderma harzianum cect 2413 produces at least three extracellular beta-1,3-glucanases. the most basic of these extracellular enzymes, named bgn13.1, was expressed when either fungal cell wall polymers or autoclaved mycelia from different fungi were used as the carbon source. bgn13.1 was purified to electrophoretic homogeneity and was biochemically characterized. the enzyme was specific for beta-1,3 linkages and has an endolytic mode of action. a synthetic oligonucleo ...19957592488
vital fluorochromes as tracers for fungal growth studies.eight fluorescent dyes were tested for staining the spores or mycelia of six fungi and for their translocation into new growth when the preloaded spores or mycelia were incubated on agar coated coverslips. the dyes studied were cellufluor, nile red, fluorescein diacetate (fda), carboxyfluorescein diacetate (cfda), chloromethylfluorescein diacetate (cmfda), aminochloromethyl coumarin (cmac), and the carbocyamines diic18(3) and dioc18(3). the fungi on which the dyes were tested included botrytis c ...19957578589
the preparation of protoplasts from aspergillus fumigatus mycelium.protoplasts have been prepared from the mycelium of aspergillus funigatus, using a lytic enzyme mixture from trichoderma harzianum. a variety of experimental conditions were investigated in order to achieve optimal conditions for protoplast production. electron micrographs showed the preparations to be free of cell-wall. material obtained by this procedure can be used as a source of cytoplasmic antigens for further analysis.19806988993
surface antigens of intact aspergillus fumigatus mycelium: their localization using radiolabelled protein a as marker.isotopically-labelled protein a from staphylococcus aureus was used as a marker to quantify binding of igg molecules to surface antigens of aspergillus fumigatus mycelium. the igg class antibodies were obtained from rabbits inoculated with mycelial fractions and from patients suffering from aspergillosis and aspergillus-related diseases. the highest incorporation of label was obtained with an antiserum from rabbits inoculated with a. fumigatus wall material. antibodies raised to other antigenic ...19846376701
purification and properties of an alpha-(1-3) glucanohydrolase from trichoderma harzianum. 19724501478
butanediol production from cellulose and hemicellulose by klebsiella pneumoniae grown in sequential coculture with trichoderma harzianum.the bioconversion of cellulose and hemicellulose substrates to 2,3-butanediol by a sequential coculture approach was investigated with the cellulolytic fungus trichoderma harzianum e58 and the fermentative bacterium klebsiella pneumoniae. vogel medium optimal for the production of the cellulolytic and xylanolytic enzymes of the fungus was found to be inhibitory to butanediol fermentation. this inhibition appeared to be due to a synergistic effect of various ingredients, particularly the salts, p ...19853909967
production and regeneration of protoplasts from the y-phase of the human pathogenic fungus paracoccidioides brasiliensis.protoplasts of y-cells and partially converted m-cells from several human isolates of paracoccidioides brasiliensis were obtained with a combined enzyme system containing novozym 234 and a chitinase. a laboratory made extract from trichoderma harzianum cbs-345-33 supplemented with chitinase induced the release of protoplasts from partially converted m-cells but not from established y-cells. a similar yield of protoplasts (1-2 x 10(5) ml-1 after 16 h) was produced by using either enzymatic system ...19947844703
potential of genes and gene products from trichoderma sp. and gliocladium sp. for the development of biological pesticides.fungal cell wall degrading enzymes produced by the biocontrol fungi trichoderma harzianum and gliocladium virens are strong inhibitors of spore germination and hyphal elongation of a number of phytopathogenic fungi. the purified enzymes include chitinolytic enzymes with different modes of action or different substrate specificity and glucanolytic enzymes with exo-activity. a variety of synergistic interactions were found when different enzymes were combined or associated with biotic or abiotic a ...19947866877
fingerprinting reveals gamma-ray induced mutations in fungal dna: implications for identification of patent strains of trichoderma harzianum.we have analyzed different patent strains and gamma-ray induced mutants of trichoderma harzianum by dna fingerprinting and pcr fingerprinting (rapd). applying wild-type phage m13 dna, with the oligonucleotides (ct)8 and (gtg)5 as probes for hybridization, as well as the oligonucleotides ggcatcggcc, (gtg)5, (cac)5 and the m13 sequence gagggtggcggttct as primers in pcr, we were able to obtain different and discriminative fingerprint patterns for all strains and mutants investigated. irradiation of ...19947954899
synergistic interaction between fungal cell wall degrading enzymes and different antifungal compounds enhances inhibition of spore germination.different classes of cell wall degrading enzymes produced by the biocontrol fungi trichoderma harzianum and gliocladium virens inhibited spore germination of botrytis cinerea in a bioassay in vitro. the addition of any chitinolytic or glucanolytic enzyme to the reaction mixture synergistically enhanced the antifungal properties of five different fungitoxic compounds against b. cinerea. the chemicals tested were gliotoxin, flusilazole, miconazole, captan and benomyl. dose response curves were det ...19948012584
sequence analysis and expression studies of a gene encoding a novel serine + alanine-rich protein in trichoderma harzianum.the promoters of constitutive genes have proven themselves to be useful parts of expression vectors for genetic engineering in different organisms. based on a differential screening of an induced cdna library, we have used a new approach to isolate constitutively expressed genes which can be used for this purpose. following this strategy, we have isolated constitutively expressed cdna clones of the mycoparasitic fungus trichoderma harzianum. one of these cdna clones corresponds to a gene (cob4) ...19948026744
fungal metabolites. xvi. structures of new peptaibols, trichokindins i-vii, from the fungus trichoderma peptaibols, trichokindins i-vii, have been isolated from the fungus trichoderma harzianum. their structures were characterized by spectrometric methods. trichokindins, which are 18-residue peptides containing one to three isovaline residues, were found to induce ca(2+)-dependent catecholamine secretion from bovine adrenal medullary chromaffin cells.19948069958
a putative catabolite-repressed cell wall protein from the mycoparasitic fungus trichoderma harzianum.a cdna clone encoding a putative cell wall protein (qid3) was isolated from a library prepared from chitin-induced mrna in cultures of the mycoparasitic fungus trichoderma harzianum. the predicted 14 kda protein shows a potential signal peptide, several hydrophobic domains and certain motifs that are structurally similar to proline-rich and glycine-rich plant cell wall proteins. expression of the qid3 gene is derepressed in the absence of glucose. when introduced in yeast, qid3 expression causes ...19948121402
effect of metabolites produced by trichoderma harzianum biotypes and agaricus bisporus on their respective growth radii in culturetrichoderma harzianum biotypes th1, th2, and th3 produced volatile metabolites in vitro which had similar fungistatic effects on the growth of agaricus bisporus. metabolites present in agar colonized by these strains also inhibited mycelial growth of a. bisporus, although the reduction in growth was less in the presence of metabolites produced by biotype th2 than that in the presence of metabolites produced by th1 or th3. a. bisporus produced metabolites in liquid culture that inhibited the grow ...19989835609
isolation and sequence of an endochitinase-encoding gene from a cdna library of trichoderma harzianum.there are no reports of gene sequences coding for extracellular chitinolytic enzymes from filamentous fungi, even though these enzymes are considered critical to the biological control of plant pathogenic fungi. the purpose of this paper was to report the isolation of a gene (then-42) encoding endochitinase (ech) from trichoderma harzianum strain p1, describe its sequence, and to determine whether it was related to genes coding for enzymes with similar functions from prokaryotic or other eukaryo ...19948125293
isolation and structure of harzianum a: a new trichothecene from trichoderma harzianum.a new trichothecene, harzianum a [1], was isolated from the soil-borne fungus trichoderma harzianum. the structure of 1 was determined by extensive spectral analyses including the nmr techniques of ps-cosy, hmqc, hmbc, and noesy. harzianum a [1] contains a (z,e,e)-2,4,6-octatriendioic acid esterified on the 4 beta hydroxyl group of trichodermol and is structurally related to the trichoverroids. harzianum a [1] showed no cytotoxicity against baby hamster kidney cells, no activity against gram-neg ...19948201317
biolistic transformation of trichoderma harzianum and gliocladium virens using plasmid and genomic dna.biolistic (biological ballistic) and protoplast-mediated procedures were compared as methods for transforming strains of gliocladium virens and trichoderma harzianum. for biolistic transformation, conidia were bombarded using a helium-driven biolistic device to accelerate m5 tungsten particles coated with plasmid or genomic dna. dna from either source contained a bacterial hygromycin b resistance gene (hygb) as a dominant selectable marker. the same sources of dna were also used to transform pro ...19938252645
characterization of two novel type i ribosome-inactivating proteins from the storage roots of the andean crop mirabilis expansa.two novel type i ribosome-inactivating proteins (rips) were found in the storage roots of mirabilis expansa, an underutilized andean root crop. the two rips, named me1 and me2, were purified to homogeneity by ammonium sulfate precipitation, cation-exchange perfusion chromatography, and c4 reverse-phase chromatography. the two proteins were found to be similar in size (27 and 27.5 kd) by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and their isoelectric points were determined to be ...199910198104
expression of two major chitinase genes of trichoderma atroviride (t. harzianum p1) is triggered by different regulatory signals.regulation of the expression of the two major chitinase genes, ech42 (encoding the chit42 endochitinase) and nag1 (encoding the chit73 n-acetyl-beta-d-glucosaminidase), of the chitinolytic system of the mycoparasitic biocontrol fungus trichoderma atroviride (= trichoderma harzianum p1) was investigated by using a reporter system based on the aspergillus niger glucose oxidase. strains harboring fusions of the ech42 or nag1 5' upstream noncoding sequences with the a. niger goxa gene displayed a gl ...199910223970
antifungal metabolites from trichoderma harzianum.a detailed examination of the metabolites produced in liquid cultures by a strain of trichoderma harzianum, isolated from wheat roots, has resulted in the identification of a further five metabolites. two of these, cyclonerodiol [5] and the octaketide keto diol 6, have previously been isolated from a strain of trichoderma koningii. the structures of the three new octaketide-derived compounds 7, 8, and 10 have been deduced from spectroscopic and chemical studies. all newly isolated compounds show ...19938277317
molecular cloning and expression in s. cerevisiae of two exochitinases from trichoderma harzianum.the synthetic exochitinase substrate 4-methylumbelliferyl n-acetylglucosamine was used to identify seven full-length exochitinase-encoding cdnas from a trichoderma harzianum cdna library by expression in yeast. the cdna clones represented transcripts of two exochitinase genes, designated as exc1 and exc2, which cross-hybridized under moderate stringency conditions in genomic southern blots. the exc1 cdna encodes a 578 amino acid polypeptide showing 72% similarity to the exc2-encoded 602-residue ...19958528140
the role of recognition in the induction of specific chitinases during mycoparasitism by trichoderma harzianum.the induction of chitinolytic enzymes in the biocontrol agent trichoderma harzianum during parasitism on sclerotium rolfsii and the role of fungal-fungal recognition in this process were studied. a change in the chitinolytic enzyme profile was detected during the interaction between the fungi, grown in dual culture on synthetic medium. before coming into contact with each other, both fungi contained a protein with constitutive 1,4-beta-n-acetylglucosaminidase activity. as early as 12 h after con ...19958535510
production of beta-xylosidase activity by trichoderma harzianum strains.nine trichoderma harzianum strains were screened for beta-xylosidase activity when grown in solid-state cultures on media containing wheat bran as the carbon source. all strains produced beta-xylosidase activity, the most active being in extracts of cultures of t. harzianum strain 4. a beta-xylosidase was purified by ammonium sulfate precipitation, ultrafiltration, gel filtration, and ion exchange chromatography from solid-state cultures of t. harzianum strain c. enzyme preparations yielded a si ...19968662186
nitrogen availability to pseudomonas fluorescens df57 is limited during decomposition of barley straw in bulk soil and in the barley rhizosphere.the availability of nitrogen to pseudomonas fluorescens df57 during straw degradation in bulk soil and in barley rhizosphere was studied by introducing a bioluminescent reporter strain (df57-n3), responding to nitrogen limitation, to model systems of varying complexity. df57-n3 was apparently not nitrogen limited in the natural and sterilized bulk soil used for these experiments. the soil was subsequently amended with barley straw, representing a plant residue with a high carbon-to-nitrogen rati ...199910508054
molecular cloning and expression of the nag1 gene (n-acetyl-beta-d-glucosaminidase-encoding gene) from trichoderma harzianum p1.a 72-kda n-acetyl-beta-d-glucosaminidase was purified from the mycoparasitic fungus trichoderma harzianum p1; antibodies were raised against it, and aa-sequences were obtained. the antibody reacted with a single 72-kda protein band in culture filtrates of t. harzianum grown on chitin, and was subsequently used to clone the corresponding nag1 gene from a lambdagt11 cdna expression library. it was interrupted by two short introns and encoded a protein of 580 amino acids. the deduced protein sequen ...19968781176
biochemical analysis of recombinant fungal mutanases. a new family of alpha1,3-glucanases with novel carbohydrate-binding domains.nucleotide sequence analysis shows that trichoderma harzianum and penicillium purpurogenum alpha1,3-glucanases (mutanases) have homologous primary structures (53% amino acid sequence identity), and are composed of two distinct domains: a nh(2)-terminal catalytic domain and a putative cooh-terminal polysaccharide-binding domain separated by a o-glycosylated pro-ser-thr-rich linker peptide. each mutanase was expressed in aspergillus oryzae host under the transcriptional control of a strong alpha-a ...200010636904
mycoparasitic interaction relieves binding of the cre1 carbon catabolite repressor protein to promoter sequences of the ech42 (endochitinase-encoding) gene in trichoderma harzianum.the fungus trichoderma harzianum is a potent mycoparasite of various plant pathogenic fungi. we have studied the molecular regulation of mycoparasitism in the host/mycoparasite system botrytis cinerea/t. harzianum. protein extracts, prepared from various stages of mycoparasitism, were used in electrophoretic mobility-shift assays (em-sas) with two promoter fragments of the ech-42 (42-kda endochitinase-encoding) gene of t. harzianum. this gene was chosen as a model because its expression is trigg ...19968962147
harziphilone and fleephilone, two new hiv rev/rre binding inhibitors produced by trichoderma harzianum.during the screening of the natural products for their ability to inhibit the binding of rev (regulation of virion expression) protein to [33p] labeled rre (rev responsive element) rna, two novel fungal metabolites, harziphilone and fleephilone, were isolated from the butanol-methanol (1:1) extract of the fermentation broth of trichoderma harzianum by bioassay guided fractionation. the structures of these two new compounds were established by spectroscopic methods. harziphilone and fleephilone s ...19968968392
[influence of bacillus intermedius rnase on growth-stimulating and antagonistic characteristics of trichoderma harzianum].bacillus intermedius rnaase (with specific activity of 1,000,000 units per one mg of protein) at concentration of 1 x 10(-3) mg/ml was shown to increase antagonistic and growth-stimulating properties of trichoderma harzianum. an application of trichodermin which was treated with an enzyme enhanced cucumber crop capacity by 15-18% in industrial conditions.19969011860
hybridization and breeding of the benomyl resistant mutant, trichoderma harziantum antagonized to phytopathogenic fungi by protoplast fusion.a diploid strain obtained from heterokaryons of trichoderma harzianum by protoplast fusion grew on minimal medium containing 100ppm benomyl. this strain inhibited the growth of the phytopathogenic fungus fusarium oxysporum f. sp. raphani on paired cultures and also protected against radish yellows and a drop in germination induced by f. oxysporum f. sp. raphani.200010830500
physiological and biochemical characterization of trichoderma harzianum, a biological control agent against soilborne fungal plant pathogens.monoconidial cultures of 15 isolates of trichoderma harzianum were characterized on the basis of 82 morphological, physiological, and biochemical features and 99 isoenzyme bands from seven enzyme systems. the results were subjected to numerical analysis which revealed four distinct groups. representative sequences of the internal transcribed spacer 1 (its 1)-its 2 region in the ribosomal dna gene cluster were compared between groups confirming this distribution. the utility of the groupings gene ...19979251205
characterization of an amylase produced by a trichoderma harzianum isolate with antagonistic activity against crinipellis perniciosa, the causal agent of witches' broom of isolate of trichoderma harzianum showing antagonistic activity against crinipellis perniciosa, the causal agent of the witches' broom disease of cocoa, produces substantial amounts of hydrolytic enzymes. an amylase purified from isolate 1051 had a molecular mass of about 68.7 kda. maximal activity against soluble starch was determined at ph 4.0 and 60 degrees c. the k(m) and v(max) values were 3.5 mg ml(-1) and 1.67 mg min(-1) of reducing sugar. the end products were mostly malto-oligosacchar ...200010913701
mr566a and mr566b, new melanin synthesis inhibitors produced by trichoderma harzianum. i. taxonomy, fermentation, isolation and biological melanin synthesis inhibitors (mr566a and b) and six related known isocyanocyclopentenes were isolated from the fermentation broth of trichoderma harzianum. the ic50 values of mr566a and b against mushroom tyrosinase were 1.72 and 47 microm, respectively. they inhibited melanin biosynthesis in b16 melanoma cells with mic values of 0.1 and 2.2 microm, respectively. also isolated from the same culture extract of t. harzianum was a new oxazole (mr93b), which showed no inhibitory activity against ...19979268001
a model for the combined effects of temperature and salt concentration on growth rate of food spoilage molds.we modeled mold growth on a solid culture medium at various temperatures and nacl concentrations by using five common food spoilage molds (penicillium roqueforti, trichoderma harzianum, paecilomyces variotii, aspergillus niger, and emericella nidulans). for the description of the growth rate (expressed as the increase in colony diameter per unit of time) as a function of temperature and nacl concentration, a six-parameter model has been developed. the model combines either the rosso-type or the ...19979327540
structural and functional properties of low molecular weight endo-1,4-beta-xylanases.there are currently four crystal structures of low molecular weight endo-1,4-beta-xylanases (e.c., i.e. family g/11 xylanases, available at the brookhaven data bank: 2 xylanases from trichoderma reesei (törrönen et al., 1994; törrönen and rouvinen, 1995) and one from bacillus circulans and another from trichoderma harzianum (campbell et al., 1993). they consist of two beta-sheets and one alpha-helix and have been described to resemble a partly-closed right hand. the catalytic residues ar ...19979335170
hydrophobin gene srh1, expressed during sporulation of the biocontrol agent trichoderma harzianum.a cdna clone encoding a spore-related hydrophobin, srhi, was isolated from a cdna bank prepared from mrna induced in sporulating cultures of trichoderma harzianum by heterologous hybridization using the hfb2 gene encoding a spore-bound hydrophobin of trichoderma reesei as a probe. based on sequence similarity the predicted protein was identified as a new member of the class-ii hydrophobin family. including the signal sequences, srhi has 65% and 56% amino-acid similarity with the t. reesei hydrop ...19979339348
the ability of soil-borne fungi to degrade organophosphonate carbon-to-phosphorus bonds.the ability of a wide variety of soil-borne fungal strains to degrade four structurally different compounds containing p-c bonds, namely the naturally occurring amino acid ciliatine, the popular herbicide glyphosate, phosphonoacetic acid and 2-amino-3-phosphonopropionic acid, was studied in order to show that soil fungi may play an important role in the biodegradation of organophosphonates. most of the strains appeared to utilize ciliatine as the sole source of phosphorus for growth. only a limi ...19979390463
unexpected homology between inducible cell wall protein qid74 of filamentous fungi and br3 salivary protein of the insect chironomus.a gene, qid74, of mycoparasitic filamentous fungus trichoderma harzianum and its allies encodes a cell wall protein that is induced by replacing glucose in the culture medium with chitin (simulated mycoparasitism conditions). because no trace of this gene can be detected in related species such as gibberella fujikuroi and saccharomyces cerevisiae, the qid74 gene appears to have arisen de novo within the genus trichoderma. qid74 protein, 687 residues long, is now seen as highly conserved tandem r ...19989600944
fungitoxicity of chemical analogs with heartwood toxins.trans-stilbene and tropolone as chemical analogs with naturally occurring fungitoxic heartwood compounds were studied with respect to their fungitoxic potency. while stilbene showed no fungitoxic activity towards the fungi aureobasidium pullulans var. melanogenum, penicillium glabrum, and trichoderma harzianum in the concentrations tested, the minimal inhibiting concentration of tropolone was 10(-3) m for penicillium glabrum and trichoderma harzianum, and 10(-5) m for aureobasidium pullulans var ...19989625794
genes from mycoparasitic fungi as a source for improving plant resistance to fungal pathogens.disease resistance in transgenic plants has been improved, for the first time, by the insertion of a gene from a biocontrol fungus. the gene encoding a strongly antifungal endochitinase from the mycoparasitic fungus trichoderma harzianum was transferred to tobacco and potato. high expression levels of the fungal gene were obtained in different plant tissues, which had no visible effect on plant growth and development. substantial differences in endochitinase activity were detected among transfor ...19989653105
chitinolytic activity at low temperature of an antarctic strain (a3) of verticillium lecanii.the chitinolytic activity of verticillium cfr. lecanii a3, a strain isolated from continental antarctica, was compared to those of two selected strains of trichoderma harzianum. after 72 h of incubation at 25 degrees c in media containing chitin as the sole carbon source, all strains showed the same enzyme activity (ca. 230 mu/ml); at 15 degrees c, the levels of enzyme activity of the three strains were similar to those obtained at 25 degrees c. at 5 degrees c, in contrast, the activity of v. le ...19989766230
antifungal activity of a novel endochitinase gene (chit36) from trichoderma harzianum rifai tm.a novel 36-kda endochitinase named chit36 has been isolated and characterized from trichoderma harzianum rifai tm. partial amino acid sequences from the purified protein were used to clone the fungal cdna, based on polymerase chain reaction with degenerate primers. the complete open reading frame encodes a 344-amino acid protein which shows 84% similarity to a putative chitinase from streptomyces coelicolor. chit36 was overexpressed under the pki1 constitutive promoter from trichoderma reesei vi ...200111425470
toxic-metabolite-producing bacteria and fungus in an indoor environment.toxic-metabolite-emitting microbes were isolated from the indoor environment of a building where the occupant was suffering serious building-related ill-health symptoms. toxic substances soluble in methanol and inhibitory to spermatozoa at <10 microg (dry weight) ml(-1) were found from six bacterial isolates and one fungus. the substances from isolates of bacillus simplex and from isolates belonging to the actinobacterial genera streptomyces and nocardiopsis were mitochondriotoxic. these substan ...200111425751
oxidation of triphenylarsine to triphenylarsineoxide by trichoderma harzianum and other fungi.arsenic resistant strains of bacteria and fungi were isolated from soil contaminated by chemical warfare agents. until now, no metabolic products of microbial attack against the phenyl residues of the model substrate triphenylarsine (tp) were found if it was incubated together with these strains in liquid culture assays. however, one of the isolated fungi, trichoderma harzianum as 11, was found to oxidize tp to triphenylarsineoxide (tpo). the yeast trichosporon mucoides sbug 801 and the white-ro ...200111482658
characterization of a chitinase and an endo-beta-1,3-glucanase from trichoderma harzianum rifai t24 involved in control of the phytopathogen sclerotium rolfsii.of 24 trichoderma isolates, t harzianum rifai (t24) showed a potential for control of the phytopathogenic basidiomycete sclerotium rolfsii. when t24 was grown on different carbon sources, growth inhibition of s. rolfsii by the t24 culture filtrate correlated with the activity of extracellular chitinase and beta-1,3-glucanase. the 43-kilodalton (kda) chitinase and the 74-kda beta-1,3-glucanase were purified from the t24 culture filtrate in two and three steps, respectively, using ammonium sulphat ...200111499921
role of the trichoderma harzianum endochitinase gene, ech42, in mycoparasitism.the role of the trichoderma harzianum endochitinase (ech42) in mycoparasitism was studied by genetically manipulating the gene that encodes ech42, ech42. we constructed several transgenic t. harzianum strains carrying multiple copies of ech42 and the corresponding gene disruptants. the level of extracellular endochitinase activity when t. harzianum was grown under inducing conditions increased up to 42-fold in multicopy strains as compared with the wild type, whereas gene disruptants exhibited p ...199910049844
purification of active cysteine proteases by affinity chromatography with attached e-64 inhibitor.cysteine proteases are implicated in many regulatory and degradative processes in animal and plant cells. many of the proteases are strongly inhibited by an irreversible inhibitor, trans-(epoxysuccinyl)-l-leucylamino-4-guanidinobutane (e-64) from aspergillus japonicus. here we report a method for purification of cysteine proteases by affinity chromatography on e-64. attachment of the inhibitor to thiopropyl sepharose through its epoxy group resulted in the loss of its irreversible activity but d ...199910092483
a refined method for the determination of saccharomyces cerevisiae cell wall composition and beta-1,6-glucan fine yeast and other fungi, cell division, cell shape, and growth depend on the coordinated synthesis and degradation of cell wall polymers. we have developed a reliable and efficient micro method to determine saccharomyces cerevisiae cell wall composition that distinguishes between beta1,3- and beta1,6-glucan. the method is based on the sequential treatment of cell walls with specific hydrolytic enzymes followed by dialysis. the low molecular weight (mw) products thus separated account for each p ...200211811978
availability of phosphorus and sulfur of insecticide origin by fungi.thirteen fungal species isolated from soil treated with pesticides were tested for their ability to mineralize and degrade three organophosphate insecticides currently used in egypt (cyolan, malathion and dursban) in liquid media free from phosphorus (p) and sulfur (s). all fungal species grew successfully on the culture media treated with the three used doses of insecticides (10, 50 and 100 ppm active ingredient) but the growth rate varied with the species, the insecticide and the doses. at 10 ...199810192894
comparative degradation of oomycete, ascomycete, and basidiomycete cell walls by mycoparasitic and biocontrol fungi.fourteen fungi (primarily representing mycoparasitic and biocontrol fungi) were tested for their ability to grow on and degrade cell walls (cws) of an oomycete (pythium ultimum), ascomycete (fusarium equisetii), and basidiomycete (rhizoctonia solani), and their hydrolytic enzymes were characterized. protein was detected in the cultural medium of eleven of the test isolates, and these fungi significantly degraded cws over the 14-day duration of the experiment. in general, a greater level of cw de ...200211888164
rapid blue light regulation of a trichoderma harzianum photolyase gene.photolyases and blue light receptors belong to a superfamily of flavoproteins that make use of blue and uva light either to catalyze dna repair or to control development. we have isolated a dna photolyase gene (phr1) from trichoderma harzianum, a common soil fungus that is of interest as a biocontrol agent against soil-borne plant pathogens and as a model for the study of light-dependent development. the sequence of phr1 is similar to other class i type i eukaryotic photolyase genes. low fluence ...199910318850
pcr-based genotyping of epidemic and preepidemic trichoderma isolates associated with green mold of agaricus bisporus.we used randomly amplified polymorphic dna (rapd)-pcr to estimate genetic variation among isolates of trichoderma associated with green mold on the cultivated mushroom agaricus bisporus. of 83 isolates examined, 66 were sampled during the recent green mold epidemic, while the remaining 17 isolates were collected just prior to the epidemic and date back to the 1950s. trichoderma harzianum biotype 4 was identified by rapd analysis as the cause of almost 90% of the epidemic-related episodes of gree ...199910347059
diversity in soil fungi from undisturbed and disturbed celtis tala and scutia buxifolia forests in the eastern buenos aires province (argentina).the rhizospheric soil microfungi from a native forest (undisturbed and disturbed) were studied using soil dilution plate and soil washing methods. fungi were isolated using slightly acid and alkaline culture media. 54 taxa were isolated: 49 from undisturbed forest soil and 37 from disturbed forest soil. acremonium sp., aspergillus ustus, coemansia pectinata, doratomyces stemonitis, fusarium solani, f. oxysporum, gliocladium roseum, humicola fusco-atra, mortierella sp., penicillium lilacinum, tri ...200212002400
comparison of the effects of temperature and water activity on growth rate of food spoilage moulds.the influence of temperature (t) and water activity (aw) on the growth rate (mu) of seven moulds (alternaria alternata, aspergillus flavus, cladosporium cladosporioides, mucor racemosus, penicillium chrysogenum, rhizopus oryzae and trichoderma harzianum) was assessed in suboptimal conditions. firstly, the dependence of fungal growth on temperature, at aw 0.99, was modelled through an approach described previously for bacteria. a dimensionless growth rate variable: mu(dimalpha)=mu/mu (optalpha) d ...200212032803
trichorzins ha and ma, antibiotic peptides from trichoderma harzianum. i. fermentation, isolation and biological properties.trichorzins ha and ma, original 18-residue peptides, were isolated from two strains of the widespread soil fungus trichoderma harzianum which have been shown to exhibit antibiotic activity against phytopathogenic fungi. these linear peptides belonging to the peptaibol class are biosynthesized as a complex of closely related analogues. nine major pure peptides, six trichorzins ha and three trichorzins ma, were isolated by reversed-phase hplc. the isolated peptides exhibited antibacterial activity ...19958557564
characterisation of two 14-3-3 genes from trichoderma reesei: interactions with yeast secretory pathway components.the 14-3-3 proteins are highly conserved, ubiquitously expressed proteins taking part in numerous cellular processes. two genes encoding 14-3-3 proteins, ftt1 and ftt2, were isolated and characterised from the filamentous fungus trichoderma reesei. ftti showed the highest sequence identity (98% at the amino acid level) to the trichoderma harzianum protein th1433. fttii is relatively distinct from ftti, showing approximately 75% identity to other fungal 14-3-3 proteins. despite their sequence div ...200212063166
trichosetin, a novel tetramic acid antibiotic produced in dual culture of trichoderma harzianum and catharanthus roseus callus.the dual culture of trichoderma harzianum and catharanthus roseus callus produced an antimicrobial compound with a remarkable activity against the gram-positive bacteria staphylococcus aureus and bacillus subtilis. structural elucidation revealed that this compound, which we have named trichosetin, is a novel tetramic acid (2,4-pyrrolidinedione) antibiotic and a homolog of the fungal metabolite equisetin. this compound however, was not produced in the individual culture of t. harzianum or c. ros ...200212132686
composting of a crop residue through treatment with microorganisms and subsequent vermicomposting.preliminary studies were conducted on wheat straw to test the technical viability of an integrated system of composting, with bioinoculants and subsequent vermicomposting, to overcome the problem of lignocellulosic waste degradation, especially during the winter season. wheat straw was pre-decomposed for 40 days by inoculating it with pleurotus sajor-caju, trichoderma harzianum, aspergillus niger and azotobacter chroococcum in different combinations. this was followed by vermicomposting for 30 d ...200212227532
isolation and characterization of two chitinase-encoding genes (cts1, cts2) from the fungus coccidioides immitis.two chitinase (cts)-encoding genes (cts) from coccidioides immitis (ci), a respiratory fungal pathogen of humans, were cloned and sequenced. both the genomic and cdna sequences are presented. the transcription start points and poly(a)-addition sites were confirmed. the cts1 gene contains five introns and a 1281-bp orf which translates a 427-amino-acid (aa) protein of 47.4 kda. the cts2 gene contains two introns and a 2580-bp orf which translates a 860-aa protein of 91.4 kda. the deduced cts1 pro ...19958566773
primary structure and expression pattern of the 33-kda chitinase gene from the mycoparasitic fungus trichoderma harzianum.a gene (chit33) from the mycoparasitic fungus trichoderma harzianum, coding for a chitinase of 33 kda, has been isolated and characterized. partial amino-acid sequences from the purified 33-kda chitinase were obtained. the amino-terminal peptide sequence was employed to design an oligonucleotide probe and was used as a primer to isolate a 1.2-kb cdna. the cdna codes for a protein of 321 amino acids, which includes a putative signal peptide of 19 amino acids. all microsequenced peptides found in ...19958575023
fatal case of trichoderma harzianum infection in a renal transplant recipient.we describe the second known case of human infection by trichoderma harzianum. a disseminated fungal infection was detected in the postmortem examination of a renal transplant recipient and confirmed in culture. the only other reported infection by this fungus caused peritonitis in a diabetic patient. the in vitro antifungal susceptibilities of the clinical strain and three other strains of trichoderma species to six antifungal drugs are provided. this case illustrates the widening spectrum of o ...199910523593
biodegradation of pyrene by sediment fungi.micromycetes were isolated from pahs-contaminated sediment and identified. they were investigated for pyrene degradation (10 mg l-1) in liquid synthetic medium for two days. among the 41 strains isolated, 10 highly degraded pyrene (> 2.4 mg g-1 dry weight): two zygomycetes (mucor racemosus, m. racemosus var. sphaerosporus), 6 deuteromycetes (gliocladium virens, penicillium simplicissimum, p. janthinellum, phialophora alba, p. hoffmannii, trichoderma harzianum), a dematiaceae (scopulariopsis brum ...200010665394
molecular characterization and identification of biocontrol isolates of trichoderma spp.the most common biological control agents (bcas) of the genus trichoderma have been reported to be strains of trichoderma virens, t. harzianum, and t. viride. since trichoderma bcas use different mechanisms of biocontrol, it is very important to explore the synergistic effects expressed by different genotypes for their practical use in agriculture. characterization of 16 biocontrol strains, previously identified as "trichoderma harzianum" rifai and one biocontrol strain recognized as t. viride, ...200010788356
enzyme diffusion from trichoderma atroviride (= t. harzianum p1) to rhizoctonia solani is a prerequisite for triggering of trichoderma ech42 gene expression before mycoparasitic contact.a plate confrontation experiment is commonly used to study the mechanism by which trichoderma spp. antagonize and parasitize other fungi. previous work with chitinase gene expression (ech42) during the precontact period of this process in which cellophane and dialysis membranes separated trichoderma harzianum and its host rhizoctonia solani resulted in essentially opposite results. here, we show that cellophane membranes are permeable to proteins up to at least 90 kda in size but that dialysis m ...200010788407
the production of hemicellulases by aerobic fungi on medium containing residues of banana plant as substrate.trichoderma harzianum strains t4 and t6, acrophialophora nainiana, and humicola grisea var. thermoidea were screened for their ability to produce carbohydrate-degrading enzyme activities in a medium containing banana plant residue as the carbon source. the best balance of enzyme activities was obtained from cultures of h. grisea var. thermoidea. xylanase activity from crude extract of a. nainiana had a maximum activity at ph 5.5-7.0 and a temperature range of 50-55 degrees c. it was stable up to ...200010835259
effect of biological suspensions on the position of the binodal curve in aqueous two-phase systems.this study is concerned with the influence of biological suspension on the position of the binodal curve in aqueous two-phase systems (atpss). three different biological suspensions (i.e., disrupted yeast, e. coli homogenate and fermentation broth from trichoderma harzianum) were selected and their impact upon atps performance was evaluated on the basis of changing volume ratio (vr) and the position of the binodal curve of biological atpss (added with biomass). biological atpss with initial vr g ...200010942267
microbial community composition affects soil fungistasis.most soils inhibit fungal germination and growth to a certain extent, a phenomenon known as soil fungistasis. previous observations have implicated microorganisms as the causal agents of fungistasis, with their action mediated either by available carbon limitation (nutrient deprivation hypothesis) or production of antifungal compounds (antibiosis hypothesis). to obtain evidence for either of these hypotheses, we measured soil respiration and microbial numbers (as indicators of nutrient stress) a ...200312571002
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