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saprophytic and keratinophilic fungi isolated from desert and cultivated soils continuously exposed to cement dust particles in egypt.forty soil samples collected from desert (uncultivated) and cultivated soils, exposed continuously to cement dust were screened for their content of saprophytic and keratinophilic fungi using the hair baiting technique and the dilution plate method. using the hair baiting technique, 21 genera and 31 species were collected from 20 samples of each of desert (15 genera and 21 species) and cultivated (17 genera and 24 species) soils, on sabouraud's dextrose agar. these included chrysosporium keratin ...19921325092
naphthoquinone pigments related to fusarubin from the fungus fusarium solani (mart.) sacc.a review is presented on the naphthoquinone pigments produced by the filamentous fungus fusarium solani (mart.) sacc., and related species. after description of the naphthoquinone structures and biogenesis, the physiological and genetical controls of pigment production are discussed. the biological properties of the main naphthoquinone pigments so far investigated are described. many problems still remain to be resolved in these fields, where nectria haematococca (berk. and br.) wr., the sexual ...19902233399
in vivo rearrangement of foreign dna by fusarium oxysporum produces linear self-replicating plasmids.particular combinations of fungal strains and transformation vectors allow for fungal rearrangement of normally integrative plasmids, resulting in the creation of linear self-replicating plasmids in fusarium oxysporum. the rearrangement results in the addition of fungal dna, including telomere consensus sequences, to plasmid termini. the mechanism by which this rearrangement occurs is unclear, but it has similarities to extrachromosomal gene amplification. a dna fragment which allows for linear ...19902345140
isolation of dna from filamentous fungi and separation into nuclear, mitochondrial, ribosomal, and plasmid components.a general procedure for purifying and efficiently separating four types of dna from filamentous fungi has been developed. the protocol involves (i) disruption of mycelial cells by blending in liquid nitrogen followed by suspension of cell contents in buffer containing high concentrations of protease and edta; (ii) deproteinization with phenol; (iii) cesium chloride/bisbenzimide density gradient centrifugation to separate nuclear dna, mitochondrial dna, and ribosomal dna; and (iv) agarose gel ele ...19836318603
the fusarium solani gene encoding kievitone hydratase, a secreted enzyme that catalyzes detoxification of a bean phytoalexin.among the antimicrobial phytoalexins produced by phaseolus vulgaris (french bean) is the prenylated isoflavonoid, kievitone. the bean pathogen, fusarium solani f. sp. phaseoli, secretes a glycoenzyme, kievitone hydratase (ec 4.2.1.95), which catalyzes conversion of kievitone to a less toxic metabolite. among f. solani strains, those that are highly virulent to p. vulgaris also produce kievitone hydratase constitutively, suggesting that the enzyme is a virulence factor. based on the n-terminal am ...19957655061
adaptation of proteases and carbohydrates of saprophytic, phytopathogenic and entomopathogenic fungi to the requirements of their ecological niches.the abilities of isolates of saprophytes (neurospora crassa, aspergillus nidulans), an opportunistic human pathogen (aspergillus fumigatus), an opportunistic insect pathogen (aspergillus flavus), plant pathogens (verticillium albo-atrum, verticillium dahliae, nectria haematococca), a mushroom pathogen (verticillium fungicola) and entomopathogens (verticillium lecanii, beauveria bassiana, metarhizium anisopliae) to utilize plant cell walls and insect cuticle components in different nutrient media ...19979202474
pectate lyase peli of erwinia chrysanthemi 3937 belongs to a new family.erwinia chrysanthemi 3937 secretes five major isoenzymes of pectate lyases encoded by the pel4, pelb, pelc, peld, and pele genes and a set of secondary pectate lyases, two of which, pell and pelz, have been already identified. we cloned the peli gene, encoding a ninth pectate lyase of e. chrysanthemi 3937. the peli reading frame is 1,035 bases long, corresponding to a protein of 344 amino acids including a typical amino-terminal signal sequence of 19 amino acids. the purified mature peli protein ...19979393696
the pseudomonas syringae pv. tomato hrpw protein has domains similar to harpins and pectate lyases and can elicit the plant hypersensitive response and bind to pectate.the host-specific plant pathogen pseudomonas syringae elicits the hypersensitive response (hr) in nonhost plants and secretes the hrpz harpin in culture via the hrp (type iii) secretion system. previous genetic evidence suggested the existence of another harpin gene in the p. syringae genome. hrpw was found in a region adjacent to the hrp cluster in p. syringae pv. tomato dc3000. hrpw encodes a 42. 9-kda protein with domains resembling harpins and pectate lyases (pels), respectively. hrpw has ke ...19989748456
microbial populations, ammonification and nitrification in soil treated with urea and inorganic salts.soil fertilization with urea at rates of 0.2 and 0.5 mg n/g soil was toxic for total counts of bacteria and fungi except with cellulolytic fungi where growth was promoted by addition of urea after 90-d incubation. also, the population numbers of both bacteria and fungi were significantly decreased when soil was amended with cacl2 and k2so4 applied at two levels (50 and 100 mumol/g soil). some alleviation of the toxic effect of either urea or the inorganic salts was observed when they were applie ...199910588055
induction of cutinolytic esterase activity during saprophytic growth of cucurbit pathogens, fusarium solani f. sp. cucurbitae races one and two (nectria haematococca mpi and mpv, respectively).cutins from fruit of cucurbita maxima and cucurbita moschata cultivars, apple and a c(16) alcohol (hexadecanol) were used to induce cutinolytic esterase activity during saprophytic growth of strains of the two cucurbit pathogens, fusarium solani f. sp. cucurbitae, race 1 (nectria haematococca mating population (mpi) and f. solani f. sp. cucurbitae, race 2 (mpv). four strains of mpv and 11 strains of mpi were were included in the study. although we were primarily interested in the two cucurbit pa ...200111164297
characterization of pisatin-inducible cytochrome p450s in fungal pathogens of pea that detoxify the pea phytoalexin pisatin.many fungi that are pathogenic on pea have the ability to demethylate and thus detoxify the pea phytoalexin pisatin. this detoxification reaction has been studied most thoroughly in nectria haematococca mp vi where it functions as a virulence trait. the enzyme catalyzing this reaction [pisatin demethylase (pda)] is a cytochrome p450. in the current study, the induction of whole-cell pda activity and the biochemical properties of pda in microsomal preparations from the pea pathogens ascochyta pis ...200111407884
identification of a novel peld gene expressed uniquely in planta by fusarium solani f. sp. pisi (nectria haematococca, mating type vi) and characterization of its protein product as an endo-pectate lyase.antibodies prepared against a pectin-inducible pectate lyase (pla) produced by a phytopathogenic fungus fusarium solani f. sp. pisi (nectria haematococca, mating type vi) were previously found to protect the host from infection. the gene (pela) and two of its homologs were cloned and sequenced. here we report the isolation of a new pectate lyase gene, peld, from a genomic library of f. solani pisi. a 1.5-kb dna fragment containing peld and its flanking regions was sequenced. the nucleotide seque ...19968806739
pcr-based construction of promoter/g-free templates for in vitro transcription analysis allows selection of plasmids with optimal activity in homologous extracts.in vitro transcription has been used for dissecting transcriptional controls in many eukaryotic systems. one modification which greatly reduces background non-specific transcription is the placement of a guanosine-free (g-free) region of dna immediately downstream from a promoter [sawadogo and roeder, proc. natl. acad. sci. usa 82 (1985) 4394-4398]; transcription in the presence of rnase t1 and 3' o-me-gtp eliminates non-specific transcripts, and produces the g-free transcripts initiated at the ...19948076823
characterization of the pda1 promoter of nectria haematococca and identification of a region that binds a pisatin-responsive dna binding factor.isolates of nectria haematococca (anamorph: fusarium solani) are able to detoxify the pea phytoalexin pisatin through expression of pisatin demethylase (pda). this enzyme is a substrate-inducible cytochrome p450 monooxyenase that is encoded by the pda gene family. in the current study, pda1, a highly inducible pda gene, was cloned and the 5' untranslated region was sequenced. the pda mrna levels were measured in pisatin-treated mycelium and found to increase by 20-fold over untreated control. ge ...19948012044
cloning and expression of cdna encoding a protein that binds a palindromic promoter element essential for induction of fungal cutinase by plant cutin.previous studies showed that a palindromic sequence located at -159 base pairs is essential for induction of cutinase gene in fusarium solani f. sp. pisi (nectria haematococca mating type vi) by the hydroxy fatty acids from plant cutin and that a 50-kda nuclear protein binds to a promoter that contains this element. screening of a phage lambda gt11 expression library with the concatenated palindromic sequence as the probe identified a cdna encoding a palindrome-binding protein (pbp). nucleotide ...19957744822
in vitro transcription from the nectria haematococca pda1 promoter in an homologous extract reflects in vivo pisatin-responsive regulation.the pda1 gene of nectria haematococca mp vi (anamorph: fusarium solani) encodes pisatin demethylase. this enzyme detoxifies the isoflavanoid phytoalexin pisatin produced by the plant on which this fungus is pathogenic. expression of pisatin demethylase activity is induced in a mycelium by pretreatment with pisatin. we have developed homologous in vitro system which accurately initiates transcription from the pda1 promoter. transcription levels in vitro reflect the same pisatin-responsive stimula ...19947750146
isolation of a phytoalexin-detoxification gene from the plant pathogenic fungus nectria haematococca by detecting its expression in aspergillus nidulans.detoxification of the pea phytoalexin pisatin via demethylation, mediated by a cytochrome p-450 monooxygenase, is thought to be important for pathogenicity of the fungus nectria haematococca on pea. to isolate a fungal gene encoding pisatin demethylating activity (pda), we transformed aspergillus nidulans with a genomic library of n. haematococca dna constructed in a cosmid which carried the a. nidulans trpc gene. transformants were selected for trp+ and then screened for pda. one transformant a ...19883065148
cutinase is not required for fungal pathogenicity on pea.cutinase, a fungal extracellular esterase, has been proposed to be crucial in the early events of plant infection by many pathogenic fungi. to test the long-standing hypothesis that cutinase of nectria haematococca (fusarium solani f sp pisi) is essential to pathogenicity, we constructed cutinase-deficient mutants by transformation-mediated gene disruption of the single cutinase gene of a highly virulent n. haematococca strain. four independent mutants were obtained lacking a functional cutinase ...19921392588
is nectria haematococca berk, and br. the perfect stage of fusarium oxysporum schl. forma pisi (lindf.) s. and h.? 196013851241
role of fungal dynein in hyphal growth, microtubule organization, spindle pole body motility and nuclear migration.cytoplasmic dynein is a microtubule-associated motor protein with several putative subcellular functions. sequencing of the gene (dhc1) for cytoplasmic dynein heavy chain of the filamentous ascomycete, nectria haematococca, revealed a 4,349-codon open reading frame (interrupted by two introns) with four highly conserved p-loop motifs, typical of cytoplasmic dynein heavy chains. the predicted amino acid sequence is 78.0% identical to the cytoplasmic dynein heavy chain of neurospora crassa, 70.2% ...19989580563
analysis of determinants of binding and transcriptional activation of the pisatin-responsive dna binding factor of nectria haematococca.pisatin is a fungistatic isoflavonoid produced by garden pea. field isolates of the ascomycete nectria haematococca mating population vi (anamorph: fusarium solani) that are highly virulent on pea have been found to possess the pda1 gene encoding a pisatin detoxifying activity. expression of pda1 is specifically and highly induced by exposure of mycelia to pisatin. a pisatin-responsive dna-binding activity has previously been identified with properties suggestive of a transcriptional regulator o ...19968850087
novel polyketide synthase from nectria haematococca.we identified a polyketide synthase (pks) gene, pksn, from a strain of nectria haematococca by complementing a mutant unable to synthesize a red perithecial pigment. pksn encodes a 2,106-amino-acid polypeptide with conserved motifs characteristic of type i pks enzymatic domains: beta-ketoacyl synthase, acyltransferase, duplicated acyl carrier proteins, and thioesterase. the pksn product groups with the aspergillus nidulans wa-type pkss involved in conidial pigmentation and melanin, bikaverin, an ...200415128560
introduction of plant and fungal genes into pea (pisum sativum l.) hairy roots reduces their ability to produce pisatin and affects their response to a fungal pathogen.pisatin is an isoflavonoid phytoalexin synthesized by pea (pisum sativum l.). previous studies have identified two enzymes apparently involved in the synthesis of this phytoalexin, isoflavone reductase (ifr), which catalyzes an intermediate step in pisatin biosynthesis, and (+)6a-hydroxymaackiain 3-o-methyltransferase (hmm), an enzyme catalyzing the terminal step. to further evaluate the involvement of these enzymes in pisatin biosynthesis, sense- and antisense-oriented cdnas of ifr and hmm fuse ...200415242174
bistability and hysteresis of the 'secteur' differentiation are controlled by a two-gene locus in nectria haematococca.bistability and hysteresis are increasingly recognized as major properties of regulatory networks governing numerous biological phenomena, such as differentiation and cell cycle progression. the full scope of the underlying molecular mechanisms leading to bistability and hysteresis remains elusive. nectria haemaotcocca, a saprophytic or pathogenic fungus with sexual reproduction, exhibits a bistable morphological modification characterized by a reduced growth rate and an intense pigmentation. bi ...200415312233
location of pathogenicity genes on dispensable chromosomes in nectria haematococca mpvi.nectria haematococca mpvi can be found in many different biological habitats but has been most studied as a pathogen of pea (pisum sativum). genetic analyses of isolates obtained from a variety of biological sources has indicated that a number of genes control pathogenicity on pea but that one important pea pathogenicity (pep) gene is pda, which confers the ability to detoxify the pea phytoalexin pisatin. in these studies, all naturally occurring isolates that lacked pda (i.e. pda- isolates) and ...19947847894
genes determining pathogenicity to pea are clustered on a supernumerary chromosome in the fungal plant pathogen nectria haematococca.three genes that contribute to the ability of the fungus nectria haematococca to cause disease on pea plants have been identified. these pea pathogenicity (pep) genes are within 25 kb of each other and are located on a supernumerary chromosome. altogether, the pep gene cluster contains six transcriptional units that are expressed during infection of pea tissue. the biochemical function of only one of the genes is known with certainty. this gene, pda1, encodes a specific cytochrome p450 that conf ...200111208022
analysis of the dynamics of fungal communities in soil via fungal-specific pcr of soil dna followed by denaturing gradient gel electrophoresis.a molecular method for profiling of fungal communities in soil was applied in experiments in soil microcosms, with two objectives, (1) to assess the persistence of two selected fungal species in soil, and (2) to analyze the response of the natural fungal community to a spill of sulphurous petrol in the same soil. to achieve the aims, two soil dna extraction methods, one originally designed for the direct extraction of bacterial community dna and the other one aimed to obtain fungal dna, were tes ...200011121612
lignin degradation in wood-feeding insects.the aromatic polymer lignin protects plants from most forms of microbial attack. despite the fact that a significant fraction of all lignocellulose degraded passes through arthropod guts, the fate of lignin in these systems is not known. using tetramethylammonium hydroxide thermochemolysis, we show lignin degradation by two insect species, the asian longhorned beetle (anoplophora glabripennis) and the pacific dampwood termite (zootermopsis angusticollis). in both the beetle and termite, signific ...200818725643
isolation of the cdnas encoding (+)6a-hydroxymaackiain 3-o-methyltransferase, the terminal step for the synthesis of the phytoalexin pisatin in pisum sativum.pisatin is the major phytoalexin produced by pea upon microbial infection. the enzyme that catalyzes the terminal step in the pisatin biosynthetic pathway is (+)6a-hydroxymaackiain 3-o-methyltransferase (hmm). we report here the isolation and characterization of two hmm cdna clones (phmm1 and phmm2) made from rna obtained from nectria haematococca-infected pea tissue. the two clones were confirmed to encode hmm activity by heterologous expression in escherichia coli. the substrate specificity of ...19979349277
molecular assays reveal the presence and diversity of genes encoding pea footrot pathogenicity determinants in nectria haematococca and in agricultural soils.the aim of this study was to develop molecular assays for investigating the presence and diversity of pathogenicity genes from the pea footrot pathogen nectria haematococca (anamorph fusarium solani f.sp. pisi) in soils.200919226389
cloning of a novel constitutively expressed pectate lyase gene pelb from fusarium solani f. sp. pisi (nectria haematococca, mating type vi) and characterization of the gene product expressed in pichia pastoris.since plant-pathogenic fungi must penetrate through pectinaceous layers of the host cell wall, pectin-degrading enzymes are thought to be important for pathogenesis. antibodies prepared against a pectin-inducible pectate lyase (pectate lyase a [pla]) produced by a phytopathogenic fungus, fusarium solani f. sp. pisi (nectria haematococca, mating type vi), was previously found to protect the host from infection. the gene (pela) and its cdna were cloned and sequenced. here we report the isolation o ...19958522511
identification of regulatory elements in the cutinase promoter from fusarium solani f. sp. pisi (nectria haematococca).the cutinase gene from fusarium solani f. sp. pisi (nectria haematococca) is induced upon contact with the plant cuticular polymer, cutin, by the unique hydroxy fatty acid monomers released by cutinase carried by virulent strains of the fungus, and this gene is also catabolite-repressed by glucose. functional elements of the cutinase promoter were studied in vivo by transforming f. solani pisi with fusions of 5'-flanking regions of the cutinase gene and the gene encoding chloramphenicol acetyltr ...19948132657
biochemical properties of the products of cytochrome p450 genes (pda) encoding pisatin demethylase activity in nectria haematococcapea plants produce the antibiotic (+)pisatin in response to infection by the fungus nectria haematococca, which can detoxify pisatin utilizing a cytochrome p450 monooxygenase called pisatin demethylase. genes (pda) have been identified that encode different whole-cell pda phenotypes that can be distinguished by the length of the lag period and the resulting amount of enzyme activity produced: pdash = short lag, high activity; pdasm = short lag, moderate activity; and pdall = long lag, low activi ...19989683653
identification of elements in the pda1 promoter of nectria haematococca necessary for a high level of transcription in vitro.expression of the pda1 gene in the ascomycete nectria haematococca mpvi (anamorph: fusarium solani) is induced by exposure of mycelium to pisatin, an isoflavonoid phytoalexin produced by its host plant, garden pea. the pda1 gene encodes a cytochrome p-450 monooxygenase which detoxifies pisatin. regulatory elements controlling transcription from the pda1 promoter were identified using a homologous nectria in vitro transcription system through analysis of 5' deletions, specific oligonucleotide com ...19968569685
functional expression and subcellular localization of the nectria haematococca mak1 phytoalexin detoxification enzyme in transgenic tobacco.medicarpin and maackiain are antifungal pterocarpan phytoalexins produced by many legumes, and are thought to be important components of the defense response of these legumes to certain fungal pathogens. the mak1 gene from the fungal pathogen nectria haematococca encodes an fad-dependent mono-oxygenase, known to specifically hydroxylate the phytoalexins medicarpin and maackiain, converting them to less fungitoxic derivatives. two binary vector constructs were made containing the coding regions f ...200111485199
the substrate specificity, enantioselectivity and structure of the (r)-selective amine : pyruvate transaminase from nectria haematococca.during the last decade the use of transaminases for the production of pharmaceutical and fine chemical intermediates has attracted a great deal of attention. transaminases are versatile biocatalysts for the efficient production of amine intermediates and many have (s)-enantiospecificity. transaminases with (r)-specificity are needed to expand the applications of these enzymes in biocatalysis. in this work we have identified a fungal putative (r)-specific transaminase from the eurotiomycetes nect ...201424618038
one enzyme makes a fungal pathogen, but not a saprophyte, virulent on a new host plant.certain genes of nectria haematococca, a fingal pathogen of pea (pisum sativum), encode pisatin demethylase (pda), a cytochrome p-450 monoxygenase that detoxifies the phytoalexin pisatin. because pda is required by n.haematococca for pathogenicity on pea, pisatin helps defend pea against n. haematococca. the possibility that pisatin is a general defense factormicrothat is, that pda can confer pathogenicity to fungi not normally pathogenic on peamicrowas investigated. genes encoding pda were tran ...198917839018
adhesion of macroconidia to the plant surface and virulence of nectria haematococca.to study spore attachment of the cucurbit pathogen nectria haematococca (anamorph, fusarium solani f. sp. cucurbitae), mutants with adhesion-deficient macroconidia were isolated. the adhesion-deficient mutants were selected after treatment with n-methyl-n' -nitro-n-nitrosoguanidine followed by repeated enrichment for macroconidia which did not attach to polystyrene. two independently derived mutants produced macroconidia with an approximately 50% reduction in attachment to polystyrene and to zuc ...199016348379
regulation of constitutively expressed and induced cutinase genes by different zinc finger transcription factors in fusarium solani f. sp. pisi (nectria haematococca).cutin monomers, generated by the low levels of constitutively expressed cutinase, induce high levels of cutinase that can help pathogenic fungi to penetrate into the host through the cuticle whose major structural polymer is cutin. we cloned three highly homologous cutinase genes, cut1, cut2, and cut3, from fusarium solani f. pisi (nectria haematococca). amino acid sequence deduced from the nucleotide sequence of cut1 and cut2/3 matched with that of the peptides from cutinase 1 and cutinase 2, r ...200211756444
survey of mycoflora and mycotoxins in egyptian soybean seeds.after four months in commercial storage, 100 soybean samples from different places of egyptian governorates were assayed for filamentous fungal growth at two incubation temperatures (28 and 45 degrees c). 73 species and 8 varieties belonging to 32 genera were isolated by the dilution plate method. at 28 degrees c, the common species were aspergillus flavus, a. fumigatus, a. niger and a. alutaceus, followed by a. terreus, penicillium chrysogenum, p. citrinum, mucor hiemalis, m. racemosus, emerice ...19938271157
cutinase gene disruption in fusarium solani f sp pisi decreases its virulence on pea.fusarium solani f sp pisi (nectria haematococca) isolate 77-2-3 with one cutinase gene produced 10 to 20% of the cutinase produced by isolate t-8 that has multiple cutinase genes, whereas cutinase gene-disrupted mutant 77-102 of isolate 77-2-3 did not produce cutinase. on the surface of pea stem segments, lesion formation was most frequent and most severe with t-8, less frequent and less severe with 77-2-3, and much less frequent and much milder with the gene-disrupted mutant. microscopic examin ...19948069105
effect of some food preservatives on the lipolytic activity of beef luncheon fungi.beef luncheon meat is one of the most popular meals in several countries in the world including egypt. thirty one fungal species and 3 species varieties were recovered from 30 samples of beef luncheon meat collected from different supermarkets in qena. alternaria, aspergillus, emericella, mucor, mycosphaerella, penicillium and rhizopus were the most common genera on the two types of media. from the above genera, the most prevalent species were alternaria alternate, aspergillus flavus, a. fumigat ...200823997619
expression and properties of three novel fungal lipases/sterol esterases predicted in silico: comparison with other enzymes of the candida rugosa-like family.lipases from the candida rugosa-like family are enzymes with great biotechnological interest. in a previous work, several enzymes from this family were identified by in silico mining of fungal genomes. here, we describe the cloning, expression, and characterization of putative lipases from the genomes of nectria haematococca, trichoderma reesei, and aspergillus niger and compared their catalytic properties with those of ope, a well-characterized sterol esterase/lipase from ophiostoma piceae. all ...201526272094
characterization of the termini of linear plasmids from nectria haematococca and their use in construction of an autonomously replicating transformation vector.the mitochondria of isolate fs37 from nectria haematococca mating population i (fusarium solani f. sp. cucurbitae) contain two linear plasmids, pfsc1 and pfsc2, of 9.2 and 8.3 kbp, respectively. evidence for a protein blocking the 5' termini of these plasmids was obtained from exonuclease digestion experiments. a single protein band with an apparent mr of 80 k was labeled when the dna-protein complex of either plasmid was reacted with [125i] bolton-hunter reagent and then digested with dnase i. ...19892598274
isolation and analysis of a novel inducible pectate lyase gene from the phytopathogenic fungus fusarium solani f. sp. pisi (nectria haematococca, mating population vi).a pectate lyase produced by fusarium solani f. sp. pisi (nectria haematococca, mating population vi) was previously shown to be essential for host infection (m. s. crawford and p. e. kolattukudy, arch. biochem. biophys. 258:196-205, 1987). pectate lyase genes have not been cloned from any phytopathogenic fungi. a gene, designated pela, encoding an inducible pectate lyase was isolated from f. solani f. sp. pisi. a probe was synthesized by polymerase chain reaction with oligonucleotide primers bas ...19921400187
cloning and expression analysis of nhl1, a gene encoding an extracellular lipase from the fungal pea pathogen nectria haematococca mp vi (fusarium solani f. sp. pisi) that is expressed in planta.the filamentous fungus nectria haematococca (anamorph fusarium solani f. sp. pisi) resides in soil, and attacks pea seedlings in the area of the underground epicotyl and upper tap root, causing foot rot disease. we detected lipase activity during in vitro growth of n. haematococca. subsequently, a lipase gene was cloned and functionally characterised by heterologous expression in saccharomyces cerevisiae. the full-length cdna of 1152 bp was cloned using a 3' race-pcr approach coupled with cdna l ...200111361331
an analysis of the phylogenetic distribution of the pea pathogenicity genes of nectria haematococca mpvi supports the hypothesis of their origin by horizontal transfer and uncovers a potentially new pathogen of garden pea: neocosmospora boniensis.the filamentous fungus nectria haematococca mating population vi (mpvi) contains a cluster of genes required to cause disease on pea. this cluster of pea pathogenicity genes (the pep cluster) is located on a supernumerary chromosome that is dispensable for normal growth in culture. the genes in the pep cluster have a different g+c content and codon usage compared with the genes located on the other chromosomes and a non-homogeneous distribution within the species. these features suggest that the ...200415118835
nht1, a transposable element cloned from a dispensable chromosome in nectria haematococca.certain isolates of the plant-pathogenic fungus nectria haematococca mating population vi (mpvi) contain dispensable chromosomes that are unstable during sexual reproduction. several of these chromosomes carry genes for phytoalexin detoxification and thus contribute to the pathogenic potential of this organism. a repeated dna sequence, nht1, was cloned from one of these dispensable chromosomes in n. haematococca mpvi. one copy of the repeated element (nht1a) was completely sequenced. it is 2,198 ...19979245836
endophytic fungi from myrcia guianensis at the brazilian amazon: distribution and bioactivity.beneficial interactions between plants and microorganisms have been investigated under different ecological, physiological, biochemical, and genetic aspects. however, the systematic exploration of biomolecules with potential for biotechnological products from this interaction still is relatively scarce. therefore, this study aimed the evaluation of the diversity and antimicrobial activity of the endophytic fungi obtained from roots, stems and leafs of myrcia guianensis (myrtaceae) from the brazi ...201424948926
mitosis and motor proteins in the filamentous ascomycete, nectria haematococca, and some related fungi.among filamentous fungi, mitosis has been studied in-depth in just a few species. the mitotic apparatuses in the ascomycetous fusarium spp. are the most clearly and readily visualized in vivo within this group; fluorescent labeling is unnecessary. this superior cytological tractability has enabled detailed studies and revealing experiments that have led the way toward a more complete understanding of fungal mitosis. some of the most important discoveries include the role of half-spindles in deve ...200211804038
breeding for highly fertile isolates of nectria haematococca mpvi that are highly virulent on pea and in planta selection for virulent recombinants.abstract the heterothallic ascomycete nectria haematococca mating population vi (anamorph fusarium solani) is a broad host range pathogen. field isolates of this fungus that are pathogenic on pea tend to be female sterile, of low fertility, and the same mating type (mat-1), whereas female fertile isolates of either mating type that are highly fertile tend to be nonpathogenic on this plant. to facilitate genetic analysis of traits that may be important in the ability of n. haematococca to parasit ...200118944283
new species from the fusarium solani species complex derived from perithecia and soil in the old world tropics.abstract: a large collection of strains belonging to the fusarium solani species complex (fssc) was isolated from soil and perithecia in primary forests in sri lanka (from fallen tree bark) and tropical australia (queensland, from fallen tree fruits and nuts). portions of the translation elongation factor 1-alpha (tef1) gene, the nuclear large subunit (nlsu), and internal transcribed spacer regions (its) of the nuclear ribosomal rna genes were sequenced in 52 isolates from soil and perithecia. t ...201121700636
the genome sequence of the fungal pathogen fusarium virguliforme that causes sudden death syndrome in soybean.fusarium virguliforme causes sudden death syndrome (sds) of soybean, a disease of serious concern throughout most of the soybean producing regions of the world. despite the global importance, little is known about the pathogenesis mechanisms of f. virguliforme. thus, we applied next-generation dna sequencing to reveal the draft f. virguliforme genome sequence and identified putative pathogenicity genes to facilitate discovering the mechanisms used by the pathogen to cause this disease.201424454689
a heptaketide naphthaldehyde produced by a polyketide synthase from nectria haematococca.bostrycoidin and fusarubin are biologically active fungal polyketides produced by nectria haematococca. this azaanthraquinone and naphthoquinone are thought to be biosynthesized via formation of a c(14) heptaketide aldehyde as a common key intermediate. a blast search against the genome of n. haematococca revealed one candidate gene (nechadraft_101778, nhpks1), which encodes a multi-domain polyketide synthase (pks) with a thiol reductase (tr) domain that would facilitate the reductive release of ...201222633689
diversity of endophytic fungi from roots of panax ginseng and their saponin yield capacities.endophytes of medicinal plants have the capacity to synthesis same or similar active substances with their hosts. to investigate the diversity and capacity to produce saponins of endophytic fungi of panax ginseng, thirty-eight strains of were isolated. polymerase chain reaction (pcr) and sequencing were used to identify the isolates, and saponins concentrations in the cultures were measured. agar diffusion method was used to test antimicrobial activity. high-performance liquid chromatography (hp ...201323543782
the supernumerary chromosome of nectria haematococca that carries pea-pathogenicity-related genes also carries a trait for pea rhizosphere competitiveness.fungi are found in a wide range of environments, and the ecological and host diversity of the fungus nectria haematococca has been shown to be due in part to unique genes on different supernumerary chromosomes. these chromosomes have been called "conditionally dispensable" (cd) since they are not needed for axenic growth but are important for expanding the host range of individual isolates. from a biological perspective, the cd chromosomes can be compared to bacterial plasmids that carry unique ...200818408061
cytological karyotyping and characterization of a 410 kb minichromosome in nectria haematococca mpi.karyotypes of the cucurbit pathogen nectria haematococca mpi (anamorph fusarium solani f. sp. cucurbitae race 1) was studied using the two standard strains atcc18098 and atcc18099. complete separation of all chromosomes was difficult with pulsed field gel electrophoresis due to both the large size and co-migration of chromosomes. in contrast, cytological karyotyping was done successfully with fluorescence microscopy combined with the germ tube burst method for sample preparation to visualize mit ...201222453120
the genome of nectria haematococca: contribution of supernumerary chromosomes to gene expansion.the ascomycetous fungus nectria haematococca, (asexual name fusarium solani), is a member of a group of >50 species known as the "fusarium solani species complex". members of this complex have diverse biological properties including the ability to cause disease on >100 genera of plants and opportunistic infections in humans. the current research analyzed the most extensively studied member of this complex, n. haematococca mating population vi (mpvi). several genes controlling the ability of indi ...200919714214
tissue-specific localization of pea root infection by nectria haematococca. mechanisms and consequences.root infection in susceptible host species is initiated predominantly in the zone of elongation, whereas the remainder of the root is resistant. nectria haematococca infection of pea (pisum sativum) was used as a model to explore possible mechanisms influencing the localization of root infection. the failure to infect the root tip was not due to a failure to induce spore germination at this site, suppression of pathogenicity genes in the fungus, or increased expression of plant defense genes. in ...200515778461
identification of the non-ribosomal peptide synthetase responsible for biosynthesis of the potential anti-cancer drug sansalvamide in fusarium solani.sansalvamide is a cyclic pentadepsipeptide produced by fusarium solani and has shown promising results as potential anti-cancer drug. the biosynthetic pathway has until now remained unidentified, but here we used an agrobacterium tumefaciens-mediated transformation (atmt) approach to generate knockout mutants of two candidate non-ribosomal peptide synthetases (nrps29 and nrps30). comparative studies of secondary metabolites in the two deletion mutants and wild type confirmed the absence of sansa ...201626936154
characterization of the gene encoding pisatin demethylase (fopda1) in fusarium oxysporum.the pea pathogen fusarium oxysporum f. sp. pisi is able to detoxify pisatin produced as a defense response by pea, and the gene encoding this detoxification mechanism, fopda1, was 82% identical to the cytochrome p450 pisatin demethylase pda1 gene in nectria haematococca. a survey of f. oxysporum f. sp. pisi isolates demonstrated that, as in n. haematococca, the pda gene of f. oxysporum f. sp. pisi is generally located on a small chromosome. in n. haematococca, pda1 is in a cluster of pea pathoge ...201122066900
effect of biostimulation and bioaugmentation on degradation of polyurethane buried in soil.this work investigated biostimulation and bioaugmentation as strategies for removing polyurethane (pu) waste in soil. soil microcosms were biostimulated with the pu dispersion agent "impranil" and/or yeast extract or were bioaugmented with pu-degrading fungi, and the degradation of subsequently buried pu was determined. fungal communities in the soil and colonizing buried pu were enumerated on solid media and were analyzed using denaturing gradient gel electrophoresis (dgge). biostimulation with ...201019948849
an abc transporter and a cytochrome p450 of nectria haematococca mpvi are virulence factors on pea and are the major tolerance mechanisms to the phytoalexin pisatin.the fungal plant pathogen nectria haematococca mpvi produces a cytochrome p450 that is responsible for detoxifying the phytoalexin pisatin, produced as a defense mechanism by its host, garden pea. in this study, we demonstrate that this fungus also produces a specific atp-binding cassette (abc) transporter, nhabc1, that enhances its tolerance to pisatin. in addition, although both mechanisms individually contribute to the tolerance of pisatin and act as host-specific virulence factors, mutations ...201121077772
origin of pisatin demethylase (pda) in the genus fusarium.host specificity of plant pathogens can be dictated by genes that enable pathogens to circumvent host defenses. upon recognition of a pathogen, plants initiate defense responses that can include the production of antimicrobial compounds such as phytoalexins. the pea pathogen nectria haematococca mating population vi (mpvi) is a filamentous ascomycete that contains a cluster of genes known as the pea pathogenicity (pep) cluster in which the pisatin demethylase (pda) gene resides. the pda gene pro ...201222985693
exploring the potential of fungal arylacetonitrilases in mandelic acid synthesis.the application of arylacetonitrilases from filamentous fungi to the hydrolysis of high concentrations of (r,s)-mandelonitrile (100-500 mm) was demonstrated for the first time. escherichia coli strains expressing the corresponding genes were used as whole-cell catalysts. nitrilases from aspergillus niger, neurospora crassa, nectria haematococca, and arthroderma benhamiae (enzymes nitan, nitnc, nitnh, and nitab, respectively) exhibited different degrees of enantio- and chemoselectivity (amide for ...201525652193
host recognition by pathogenic fungi through plant flavonoids.a common characteristic among fungal pathogens of plants is that each specializes on a narrow range of specific plants as hosts. one adaptation to a specific host plant is the recognition of the host's chemicals which can be used to trigger genes or developmental pathways needed for pathogenesis. the production of characteristic flavonoids by plants, particularly those exuded from roots by legumes, appear to be used as signals for various microbes, including symbionts as well as pathogens. nectr ...200212083470
genetic and biochemical characterization of nectria haematococca strains with adhesive and adhesion-reduced macroconidia.a previous study reported the isolation of two mutants (le1 and le2) of the plant pathogenic fungus nectria haematococca (anamorph, fusarium solani f. sp. cucurbitae) with macroconidia with reduced ability to adhere (att) to zucchini fruits and polystyrene. the adhesion-reduced-phenotype in le1 and le2 macroconidia is temperature sensitive and dependent on the concentration of nutrients. classical genetic analysis of progeny derived from le1 identified a mutation in a genetic locus, named att1. ...199416349181
physical mapping of plasmid and cosmid clones in filamentous fungi by fiber-fish.fluorescence in situ hybridization to extended dna fibers (fiber-fish) serves as a powerful tool for direct physical mapping in plants and animals. here, we show that fiber-fish is useful for contig mapping as well as for estimating the physical distance between genetic markers in fungi. a five-cosmid contig from a chromosome of nectria haematococca and four cloned genetic markers from a linkage map of cochliobolus heterostrophus were chosen as models for the application of this technology. in n ...200212223186
electrophoretic karyotyping and gene mapping of seven formae speciales in fusarium solani.chromosomal dnas of 22 strains in 7 formae speciales (f. spp.) of fusarium solani were compared by pulsed field gel electrophoresis (pfge) and gene mapping on the chromosomes. using pfge, complete separation of the full components of the genome was not attained, due to the limited resolution of large chromosomes, but 5-12 chromosomes with sizes of 0.6-5.7 mbp were resolvable for every strain. although each strain had a unique banding profile, similarity in the banding profile was noticed among s ...200212172966
cloning of a new pectate lyase gene pelc from fusarium solani f. sp. pisi (nectria haematococca, mating type vi) and characterization of the gene product expressed in pichia pastoris.antibodies prepared against a pectate lyase (pla) produced by a phytopathogenic fungus fusarium solani f. sp. pisi (nectria haematococca, mating type vi) were previously found to protect the host against infection. the cdna and gene (pela) for pla were cloned and sequenced. a new pectate lyase gene, pelc, was isolated from a genomic library of f. solani pisi with pela cdna as a probe. a 1.3-kb dna fragment containing the pelc gene and its flanking regions was identified and sequenced. the coding ...19957487098
a comparative study of nitrilases identified by genome mining.escherichia coli strains expressing different nitrilases transformed nitriles or kcn. six nitrilases (from aspergillus niger (2), a. oryzae, neurospora crassa, arthroderma benhamiae, and nectria haematococca) were arylacetonitrilases, two enzymes (from a. niger and penicillium chrysogenum) were cyanide hydratases and the others (from p. chrysogenum, p. marneffei, gibberella moniliformis, meyerozyma guilliermondi, rhodococcus rhodochrous, and r. ruber) preferred (hetero)aromatic nitriles as subst ...201323475593
altered susceptibility to infection by sinorhizobium meliloti and nectria haematococca in alfalfa roots with altered cell cycle.most infections of plant roots are initiated in the region of elongation; the mechanism for this tissue-specific localization pattern is unknown. in alfalfa expressing psugt1 antisense mrna under the control of the cauliflower mosaic virus (camv) 35s promoter, the cell cycle in roots is completed in 48 h instead of 24 h, and border cell number is decreased by more than 99%. these plants were found to exhibit increased root-tip infection by a fungal pathogen and reduced nodule formation by a bact ...200415042410
phylogenetic analysis of fusarium solani associated with the asian longhorned beetle, anoplophora glabripennis.culture-independent analysis of the gut of a wood-boring insect, anoplophora glabripennis (coleoptera: cerambycidae), revealed a consistent association between members of the fungal fusarium solani species complex and the larval stage of both colony-derived and wild a. glabripennis populations. using the translation elongation factor 1-alpha region for culture-independent phylogenetic and operational taxonomic unit (otu)-based analyses, only two otus were detected, suggesting that genetic varian ...201226467954
in silico analysis and prioritization of drug targets in fusarium solani.mycotic keratitis has emerged as a major ophthalmic problem and a leading cause of blindness, since its recognition in 1879. filamentous fungi are major causative of mycotic keratitis. in india, the main etiological organism responsible for mycotic keratitis is aspergillus species followed by fusarium species. in south india, fusarium based keratitis scales up to 43%. nearly one-third of mycotic keratitis treatment results in failure, as fungal infections are highly resistant to antibiotic thera ...201525555413
recombinant expression of a novel fungal immunomodulatory protein with human tumor cell antiproliferative activity from nectria haematococca.to our best knowledge, all of the fungal immunomodulatory proteins (fips) have been successfully extracted and identified in basidomycetes, with only the exception of fip from ascomycete nectria haematococca (fip-nha) discovered through homology alignment most recently. in this work, a gene encoding fip-nha was synthesized and recombinantly expressed in an escherichia coli expression system. sds-page and maldi-ms analyses of recombinant fip-nha (rfip-nha) indicated that the gene was successfully ...201425272229
genetic analysis of the role of phytoalexin detoxification in virulence of the fungus nectria haematococca on chickpea (cicer arietinum).chickpea (cicer arietium l.) produces the antimicrobial compounds (phytoalexins) medicarpin and maackiain in response to infection by microorganisms. nectria haematococca mating population (mp) vi, a fungus pathogenic on chickpea, can metabolize maackiain and medicarpin to less toxic products. these reactions are thought to be detoxification mechanisms in n. haematococca mp vi and required for pathogenesis by this fungus on chickpea. in the present study, these hypotheses were tested by examinin ...199216348672
three genes for metabolism of the phytoalexin maackiain in the plant pathogen nectria haematococca: meiotic instability and relationship to a new gene for pisatin demethylase.some isolates of the plant-pathogenic fungus nectria haematococca mating population (mp) vi metabolize maackiain and medicarpin, two antimicrobial compounds (phytoalexins) synthesized by chickpea (cicer arietinum l.). the enzymatic modifications by the fungus convert the phytoalexins to less toxic derivatives, and this detoxification has been proposed to be important for pathogenesis on chickpea. in the present study, loci controlling maackiain metabolism (mak genes) were identified by crosses a ...199216348671
ecological and physiological studies on soil fungi at western region, libya.sixty three species and 5 varieties belonging to 30 fungal genera were collected from 75 soil samples. cultivated (29 genera and 58 species + 5 var.), desert (22 and 35 + 2 var.) and saline soil (21 and 41 + 1 var.) fungi were recovered on glucose-, cellulose- and 50% sucrose-czapek's agar at 28℃. the most common genera were alternaria, aspergillus, emericella, fusarium, mycosphaerella, nectria and penicillium. the most prevalent species from the three types of soils on the three types of media ...200823997599
a binuclear zinc transcription factor binds the host isoflavonoid-responsive element in a fungal cytochrome p450 gene responsible for detoxification.the pda1 gene of the filamentous fungus nectria haematococca mpvi (anamorph: fusarium solani) encodes pisatin demethylase, a cytochrome p450. pisatin is a fungistatic isoflavonoid produced by garden pea (pisum sativum), a host for this fungus. pisatin demethylase detoxifies pisatin and functions as a virulence factor for this fungus. pisatin induces pda1 expression both in cultured mycelia as well as during pathogenesis on pea. the regulatory element within pda1 that provides pisatin-responsive ...200312823815
a bac based physical map and genome survey of the rice false smut fungus villosiclava virens.rice false smut caused by villosiclava virens is a devastating fungal disease that spreads in major rice-growing regions throughout the world. however, the genomic information for this fungal pathogen is limited and the pathogenic mechanism of this disease is still not clear. to facilitate genetic, molecular and genomic studies of this fungal pathogen, we constructed the first bac-based physical map and performed the first genome survey for this species.201324341590
modulating ca²⁺ signals: a common theme for tmem16, ist2, and tmc.since the discovery of tmem16a (anoctamin 1, ano1) as ca(2+)-activated cl(-) channel, the protein was found to serve different physiological functions, depending on the type of tissue. subsequent reports on other members of the anoctamin family demonstrated a broad range of yet poorly understood properties. compromised anoctamin function is causing a wide range of diseases, such as hearing loss (ano2), bleeding disorder (ano6), ataxia and dystonia (ano3, 10), persistent borrelia and mycobacteria ...201626700940
meiotic inheritance of a fungal supernumerary chromosome and its effect on sexual fertility in nectria haematococca.pda1-conditionally dispensable chromosome (cdc) of nectria haematococca mp vi has long served as a model of supernumerary chromosomes in plant pathogenic fungi because of pathogenicity-related genes located on it. in our previous study, we showed the dosage effects of pda1-cdc on pathogenicity and homoserine utilization by exploiting tagged pda1-cdc with a marker gene. cdc content of mating partners and progenies analyzed by pcr, pfge combined with southern analysis and chromosome painting via f ...201526399187
x-ray structure of a calcium-activated tmem16 lipid scramblase.the tmem16 family of proteins, also known as anoctamins, features a remarkable functional diversity. this family contains the long sought-after ca(2+)-activated chloride channels as well as lipid scramblases and cation channels. here we present the crystal structure of a tmem16 family member from the fungus nectria haematococca that operates as a ca(2+)-activated lipid scramblase. each subunit of the homodimeric protein contains ten transmembrane helices and a hydrophilic membrane-traversing cav ...201425383531
extracellular dna is required for root tip resistance to fungal infection.plant defense involves a complex array of biochemical interactions, many of which occur in the extracellular environment. the apical 1- to 2-mm root tip housing apical and root cap meristems is resistant to infection by most pathogens, so growth and gravity sensing often proceed normally even when other sites on the root are invaded. the mechanism of this resistance is unknown but appears to involve a mucilaginous matrix or "slime" composed of proteins, polysaccharides, and detached living cells ...200919700564
duplication of a conditionally dispensable chromosome carrying pea pathogenicity (pep) gene clusters in nectria haematococca.a supernumerary chromosome called a conditionally dispensable chromosome (cdc) is essential for pathogenicity of nectria haematococca on pea. among several cdcs discovered in n. haematococca, the pda1 cdc that harbors the pisatin demethylation gene pda1 is one of the best-studied cdcs and serves as a model for plant-pathogenic fungi. although the presence of multiple copies is usual for supernumerary chromosomes in other eukaryotes, this possibility has not been examined well for any cdcs in n. ...200717990957
extracellular proteins in pea root tip and border cell exudates.newly generated plant tissue is inherently sensitive to infection. yet, when pea (pisum sativum) roots are inoculated with the pea pathogen, nectria haematococca, most newly generated root tips remain uninfected even though most roots develop lesions just behind the tip in the region of elongation. the resistance mechanism is unknown but is correlated spatially with the presence of border cells on the cap periphery. previously, an array of >100 extracellular proteins was found to be released whi ...200717142479
a cytoplasmic dynein required for mitotic aster formation in vivo.an astral pulling force helps to elongate the mitotic spindle in the filamentous ascomycete, nectria haematococca. evidence is mounting that dynein is required for the formation of mitotic spindles and asters. obviously, this would be an important mitotic function of dynein, since it would be a prerequisite for astral force to be applied to a spindle pole. missing from the evidence for such a role of dynein in aster formation, however, has been a dynein mutant lacking mitotic asters. to determin ...19989701559
inducing the loss of conditionally dispensable chromosomes in nectria haematococca during vegetative growth.a procedure for inducing and detecting the loss of conditionally dispensable (cd) chromosomes in filamentous fungi during vegetative growth was developed using nectria haematococca mating population vi as a model. cd chromosomes in two different isolates of n. haematococca were tagged via integrative transformation with a gene conferring resistance to hygromycin b. in each case the transformation vector included chromosome-specific dna in order to direct its homologous recombination with the des ...19989560438
atomistic insight into lipid translocation by a tmem16 scramblase.the transmembrane protein 16 (tmem16) family of membrane proteins includes both lipid scramblases and ion channels involved in olfaction, nociception, and blood coagulation. the crystal structure of the fungal nectria haematococca tmem16 (nhtmem16) scramblase suggested a putative mechanism of lipid transport, whereby polar and charged lipid headgroups move through the low-dielectric environment of the membrane by traversing a hydrophilic groove on the membrane-spanning surface of the protein. he ...201627872308
a fungal kinesin required for organelle motility, hyphal growth, and morphogenesis.a gene (nhkin1) encoding a kinesin was cloned from nectria haematococca genomic dna by polymerase chain reaction amplification, using primers corresponding to conserved regions of known kinesin-encoding genes. sequence analysis showed that nhkin1 belongs to the subfamily of conventional kinesins and is distinct from any of the currently designated kinesin-related protein subfamilies. deletion of nhkin1 by transformation-mediated homologous recombination caused several dramatic phenotypes: a 50% ...19989436993
identification and chromosomal locations of a family of cytochrome p-450 genes for pisatin detoxification in the fungus nectria haematococca.the ability to detoxify the phytoalexin, pisatin, an antimicrobial compound produced by pea (pisum sativum l.), is one requirement for pathogenicity of the fungus nectria haematococca on this plant. detoxification is mediated by a cytochrome p-450, pisatin demethylase, encoded by any one of six pda genes, which differ with respect to the inducibility and level of pisatin demethylase activity they confer, and which are associated with different levels of virulence on pea. a previously cloned pda ...19912034215
genomic clustering and homology between het-s and the nwd2 stand protein in various fungal genomes.prions are infectious proteins propagating as self-perpetuating amyloid polymers. the [het-s] prion of podospora anserina is involved in a cell death process associated with non-self recognition. the prion forming domain (pfd) of het-s adopts a β-solenoid amyloid structure characterized by the two fold repetition of an elementary triangular motif. [het-s] induces cell death when interacting with het-s, an allelic variant of het-s. when templated by [het-s], het-s undergoes a trans-conformation, ...201222493719
19f nuclear magnetic resonance analysis of 5-fluorouracil metabolism in wild-type and 5-fluorouracil-resistant nectria haematococca.a mutant (fura3) was isolated from the s1 wild-type strain of nectria haematococca on the basis of its resistance to 5-fluorouracil (5fu). this mutant has greatly reduced activity of uracil phosphoribosyltransferase, a pyrimidine salvage enzyme catalyzing the synthesis of ump from uracil. the metabolism of 5fu was examined in both strains by using 19f nuclear magnetic resonance spectroscopy. in the s1 strain, 5fu appears to be metabolized by two pathways operating simultaneously: (i) conversion ...19892604390
role of oxygenases in pisatin biosynthesis and in the fungal degradation of maackiain.some isolates of the plant pathogen nectria haematococca detoxify the isoflavonoid phytoalexin (-)maackiain by hydroxylation at carbon 6a. precursor feeding studies strongly suggest that the penultimate step in (+)pisatin biosynthesis by pisum sativum is 6a-hydroxylation of (+)maackiain. we have used (18)o labeling to test the involvement of oxygenases in these two reactions. when fungal metabolism of maackiain took place under (18)o(2), the product was labeled with 99% efficiency; no label was ...198716665251
expression of the pisatin detoxifying genes (pda) of nectria haematococca in vitro and in planta.the phytopathogenic fungus nectria haematococca detoxifies pisatin, a phytoalexin produced by pea. pisatin demethylating ability (a phenotype called pda) is due to pisatin demethylase (pdm) and the genes encoding this enzyme are called pda. some isolates rapidly acquire a high to moderate rate of pisatin demethylating activity culture in response to pisatin (phenotypes pdash and pdasm), while other isolates only slowly demethylate pisatin (phenotype pdall). here we report that pda-specific rna l ...19968755624
identification of new pisatin demethylase genes (pda5 and pda7) in nectria haematococca and non-mendelian segregation of pisatin demethylating ability and virulence on pea due to loss of chromosomal elements.previous studies have shown that high virulence on pea in nectria haematococca mating population vi is linked to the ability to detoxify the pea phytoalexin, pisatin, via demethylation (pda). to test this linkage further, a highly virulent pda(+) isolate (34-18) was used as the recurrent parent in backcrosses to pda(-) isolates, but most of the progeny were low in virulence on pea, and tetrad analysis gave conflicting ratios for the genetic control of pda. southern analysis of 34-18 and progeny ...200212409098
pisatin demethylase genes are on dispensable chromosomes while genes for pathogenicity on carrot and ripe tomato are on other chromosomes in nectria haematococca.studies on the wide-host-range fungus nectria haematococca mp vi have shown a linkage between virulence on pea and five of nine pda genes that encode the ability to detoxify the pea phytoalexin, pisatin. most of the pda genes are on chromosomes of approximately 1.6 megabases (mb) and two of these genes, pda1-2 and pda6-1, have been demonstrated to reside on approximately 1.6-mb chromosomes that can be lost during meiosis. prior studies also have shown that the dispensable chromosome carrying pda ...200212182342
distribution of the pea pathogenicity ( pep) genes in the fungus nectria haematococca mating population vi.previous studies identified a cluster of six genes that are expressed in the fungus nectria haematococca mating population vi during infection of pea. four of these genes were shown to contribute to pathogenicity on pea and were called pep genes for pea pathogenicity. the cluster is located on a "conditionally dispensable" (cd) chromosome and has features similar to bacterial pathogenicity islands. in this study, the occurrence and location of members of the pep cluster were analyzed in laborato ...200212073092
photoinduced perithecial formation by nectria haematococca on media containing either l-tyrosine; l-phenylalanine; or d-glucose+nano3 as sole carbon and nitrogen sources. 19695344738
physical map of a conditionally dispensable chromosome in nectria haematococca mating population vi and location of chromosome breakpoints.certain isolates of the plant pathogenic fungus nectria haematococca mating population (mp) vi contain a 1.6-mb conditionally dispensable (cd) chromosome carrying the phytoalexin detoxification genes mak1 and pda6-1. this chromosome is structurally unstable during sexual reproduction. as a first step in our analysis of the mechanisms underlying this chromosomal instability, hybridization between overlapping cosmid clones was used to construct a map of the mak1 pda6-1 chromosome. the map consists ...200010880471
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