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effects of mutagen-sensitive mus mutations on spontaneous mitotic recombination in aspergillus.methyl methane-sulfonate (mms)-sensitive, radiation-induced mutants of aspergillus were shown to define nine new dna repair genes, musk to muss. to test mus mutations for effects on mitotic recombination, intergenic crossing over was assayed between color markers and their centromeres, and intragenic recombination between two distinguishable ade alleles. of eight mutants analyzed, four showed significant deviations from mus+ controls in both tests. two mutations, musk and musl, reduced recombina ...19921582555
cooperative regulation of cell proliferation by calcium and calmodulin in aspergillus nidulans.calcium and calmodulin have been widely implicated in the control of cell proliferation. we have created a strain of the genetically tractable filamentous fungus, aspergillus nidulans, that is conditional for calmodulin expression. this was accomplished by replacing the unique endogenous calmodulin gene with one regulated by the inducible alcohol dehydrogenase (alca) gene promoter by homologous recombination. this strain cannot grow when the cells are incubated in medium containing a carbon sour ...19921584213
regulation of aspergillus nidulans penicillin biosynthesis and penicillin biosynthesis genes acva and ipna by glucose.expression of the aspergillus nidulans penicillin biosynthesis genes acva and ipna, encoding delta-(l-alpha-aminoadipyl)-l-cysteinyl-d-valine synthetase and isopenicillin n synthetase, respectively, was analyzed. the intergenic region carrying the divergently oriented promoters was fused in frame in both orientations to escherichia coli lacz and e. coli uida reporter genes. each construct permits simultaneous expression studies of both genes. transformants of a. nidulans carrying a single copy o ...19921592830
functional analysis of the expression of the 3'-phosphoglycerate kinase pgk gene in aspergillus nidulans.a functional analysis of the aspergillus nidulans 3-phosphoglycerate kinase pgk promoter was undertaken using gene fusions to the lacz gene of escherichia coli, and introducing these into a beta-galactosidase-deficient strain of a. nidulans. expression of a particular gene fusion in transformed strains depends upon the site of integration of the vector into the genome, and when specifically targeted to the catabolic quinate dehydrogenase qute (selective marker) locus is directly proportional to ...19921603065
isolation and characterization of the aspergillus niger pyruvate kinase gene.the aspergillus niger gene encoding pyruvate kinase was cloned by heterologous hybridization using a fragment from the corresponding yeast gene as a probe. the primary structure of the gene, including 5' and 3' flanking sequences, was determined. the structural part of the a. niger pkia gene is 2054 bp long and is interrupted by seven putative introns. splicing of the intron sequences results in an open reading frame of 1578 bp, encoding a protein of 526 amino-acid residues and a molecular weigh ...19921611667
fungi associated with bovine abortion in the northern plains states (usa).mycotic infection was diagnosed in 6.8% of 6,858 cases of bovine abortion and stillbirth examined during a 9-year period. aspergilli were associated with approximately 5% of all abortion cases and 71% of 446 cases that were cultured for fungi and diagnosed as mycotic abortion. aspergillus fumigatus was the most frequent isolate (62%), followed by a. terreus (6.7%), emericella (aspergillus) nidulans (3.0%), a. flavus (2.9%), and e. rugulosus (less than 1.0%). zygomycetes (absidia, mortierella, rh ...19921616983
carbon catabolite repression can account for the temporal pattern of expression of a penicillin biosynthetic gene in aspergillus nidulans.aspergillus nidulans synthesizes penicillins as secondary metabolites when grown under certain culture conditions. broths containing carbon (c) sources that give rise to carbon catabolite repression (ccr) support a much lower antibiotic yield than broths with non-repressing c sources. steady-state levels of the isopenicillin n synthetase (ipns) gene transcript are considerably reduced in mycelia grown with repressing c sources and are depressed in mycelia grown with sugars which do not cause ccr ...19921625576
roles of fad and 8-hydroxy-5-deazaflavin chromophores in photoreactivation by anacystis nidulans dna photolyase.dna photolyase from the cyanobacterium anacystis nidulans contains two chromophores, flavin adenine dinucleotide (fadh2) and 8-hydroxy-5-deazaflavin (8-hdf) (eker, a. p. m., kooiman, p., hessels, j. k. c., and yasui, a. (1990) j. biol. chem. 265, 8009-8015). while evidence exists that the flavin chromophore (in fadh2 form) can catalyze photorepair directly and that the 8-hdf chromophore is the major photosensitizer in photoreactivation it was not known whether 8-hdf splits pyrimidine dimer direc ...19921639785
the bimb3 mutation of aspergillus nidulans uncouples dna replication from the completion of mitosis.a conditionally lethal mutation in the bimb gene of aspergillus nidulans disrupts the normal regulatory patterns associated with mitotic events. this results in dna replication in the absence of the completion of mitosis in the mutant at restrictive temperature. this defect yields large polyploid nuclei after several hours at restrictive temperature. the bimb gene has been cloned by genetic mapping and chromosome walking from the previously cloned amds gene. the cloned dna complements the temper ...19921639810
cloning of chromosome i dna from saccharomyces cerevisiae: analysis of the fun52 gene, whose product has homology to protein kinases.a gene whose product has homology to protein kinases and is closely related to the aspergillus nidulans nima cell-cycle gene was identified on chromosome i of the yeast, saccharomyces cerevisiae. this gene has been temporarily designated fun52, where fun is the acronym for 'function unknown now'. in a. nidulans, nima is required to enter mitosis. in addition, overexpression of nima causes premature onset of mitosis and cell cycle arrest. in contrast, s. cerevisiae cells that were either deleted ...19921644305
metabolism of folate glutamates in aspergillus nidulans. 19937508173
nucleotide sequence of the large mitochondrial rrna gene of penicillium chrysogenum.the nucleotide sequence of a large rrna (1-rrna) gene and its flanking regions in the cloned fragments of mitochondrial (mt) dna from penicillium chrysogenum nrrl1951 (sekiguchi j., ohsaki, t., yamamoto, h., koichi, k. and shida, t. (1990) j. gen. microbiol. 136, 535-543) was determined and compared with those in aspergillus nidulans and neurospora crassa mitochondrial dnas. the p. chrysogenum mt 1-rrna gene has a 1678 bp intron which intervenes between a 2835 bp 5' exon and a 581 bp 3' exon, an ...19937680578
an evaluation of the use of in vitro tubulin polymerisation, fungal and wheat assays to detect the activity of potential chemical aneugens.the test chemicals included in the ec aneuploidy project were evaluated for their ability to induce aneuploidy or aneuploidy related endpoints in assays using in vitro tubulin polymerisation, fungi and wheat. the results obtained demonstrated considerable qualitative and quantitative differences between the responses of the assays to the 10 test chemicals. fungal assays failed to respond to the potent mammalian spindle poisons colchicine and vinblastine and only three chemicals were positive in ...19937683381
molecular cloning, expression and structure of the endo-1,5-alpha-l-arabinase gene of aspergillus niger.secretion of endo-1,5-alpha-l-arabinase a (abn a) by an aspergillus niger xylulose kinase mutant upon mycelium transfer to medium containing l-arabitol was immunochemically followed with time to monitor its induction profile. a cdna expression library was made from polya+ rna isolated from the induced mycelium. this library was immunochemically screened and one abn a specific clone emerged. the corresponding abna gene was isolated from an a. niger genomic library. upon southern blot analysis, a ...19937764386
design of an object-oriented database for reverse genetics.we present the design of an object-oriented database system for reverse genetics applications. such a database will encapsulate not only the data in the genetic and physical maps, but also the methods used to create the maps as well as methods to link them to other databases, such as genbank, pir, and medline. the purpose of this database is to provide the fungal genetics community with an electronic tool for identifying the biochemical function of any dna fragment in the database--electronic re ...19937584341
a glucose-derepressed promoter for expression of heterologous products in the filamentous fungus aspergillus nidulans.we describe a putative binding sequence (gcggggc) for the glucose-responsive repressor protein crea at two positions upstream of the transcription start site of the alcohol dehydrogenase i (alca) gene of aspergillus nidulans. to positively identify the putative binding sites as crea-specific, the gcggggc blocks were mutated at five internal nucleotide positions to gtactac and reintroduced into the wild type alca promoter driving expression of the endogenous alcohol dehydrogenase i gene. this cre ...19937763860
cloning of the aspergillus niger gene encoding alpha-l-arabinofuranosidase a.using l-arabitol as an inducer, simple induction conditions were established that resulted in high-level expression of alpha-l-arabinofuranosidase a by an aspergillus niger d-xylulose kinase mutant strain. these conditions were adapted to construct a cdna expression library from which an alpha-l-arabinofuranosidase a cdna clone was isolated using specific antiserum. the corresponding gene encoding alpha-l-arabinofuranosidase a (abfa) was isolated from a genomic library and cloned into a high cop ...19937764056
development of a new transformant selection system for penicillium chrysogenum: isolation and characterization of the p. chrysogenum acetyl-coenzyme a synthetase gene (faca) and its use as a homologous selection marker.a new transformation system for the filamentous fungus penicillium chrysogenum is described, based on the use of the homologous acetyl-coenzyme a synthetase (faca) gene as a selection marker. acetate-non-utilizing (fac-) strains of p. chrysogenum were obtained by positive selection for spontaneous resistance to fluoroacetate. among these fac mutants putative faca strains were selected for a loss of acetyl-coenzyme a (coa) synthetase activity. the faca gene, coding for the enzyme acetyl-coa synth ...19937765289
the omps gene of vibrio cholerae encodes a growth-phase-dependent maltoporin.the outer membrane of vibrio cholerae contains a maltose-inducible major protein, omps (43 kda), that is common to different isolates. nucleotide sequence analysis of the corresponding structural gene, omps, revealed an open reading frame encoding a 412-amino-acid polypeptide. the amino acid sequence of omps is similar to that of lamb, the escherichia coli maltoporin, and to scry or klebsiella pneumoniae, although the antigenic determinants of these proteins are different. the cloned omps gene c ...19937934851
a study of the alkaline proteases secreted by different aspergillus species.strains from several species of aspergillus were grown in the presence of soluble collagen, and the major secreted proteins present in the culture fluid were examined for proteolytic activity. the possibility of relatedness among the alkaline proteases secreted by aspergillus was studied by probing extracts from the various species with polyclonal antisera raised to the isolated alkaline proteases of a. fumigatus and a. oryzae. the pathogenic species a. flavus, a. terreus and a. nidulans hydroly ...19937935565
characterization of an aspergillus nidulans genomic dna fragment conferring phosphate-non-repressible acid-phosphatase activity.a clone from an aspergillus nidulans library was identified by its ability to confer enhanced staining for acid phosphatase (apase) activity upon phosphatase-deficient a. nidulans mutants. this apase activity is not repressed by high phosphate concentrations in the medium. the 2.9-kb nucleotide sequence in the region of the clone responsible for the effect reveals two potential protein-coding genes with a common n terminus. one corresponds to an open reading frame (orf) with no introns, encoding ...19937916713
fungal catabolic gene regulation: molecular genetic analysis of the amds gene of aspergillus nidulans.aspergillus nidulans is an excellent experimental organism for the study of gene regulation. genetic and molecular analyses of trans-acting and cis-acting mutations have revealed a complex pattern of regulation involving multiple independent controls. expression of the amds gene is regulated by the facb and amda genes which encode positively acting regulatory proteins mediating a major and a minor form of acetate induction respectively. the product of the amdr gene mediates omega amino acid indu ...19938119589
the avr9 race-specific elicitor of cladosporium fulvum is processed by endogenous and plant proteases.the avirulence gene avr9 of the fungal tomato pathogen cladosporium fulvum encodes a race-specific peptide elicitor that induces a hypersensitive response in tomato plants carrying the complementary resistance gene cf9. the avr9 gene is highly expressed when c. fulvum is growing in the plant and the elicitor accumulates in infected leaves as a 28-amino acid (aa) peptide. in c. fulvum grown in vitro, the peptide elicitor is not produced in detectable amounts. to produce significant amounts of the ...19938208859
heat resistance of fungi from soil.the survival of fungi from soil samples has been investigated after exposure to temperatures of 60, 70, 80 and 90 degrees c in sabouraud agar. the least resistant fungi surviving 60 degrees c for 60 min were the aspergillus (a.) niger group, chaetomium spp, penicillium spp, and scytalidium lignicola. none of these survived 70 degrees c for 10 min. the next group surviving 70 degrees c for 60 min included the a. glaucus group, byssochlamys nivea, dichotomomyces cejpii, gelasinospora spp, rhizocto ...19938217516
preliminary studies of two active site mutants of galactose oxidase. 19938224464
galactose oxidase: molecular analysis and mutagenesis studies. 19938224504
characterisation, cloning and integrative properties of the gene encoding urate oxidase in aspergillus nidulans.a number of mutations have been obtained which define the structural gene (uaz) coding for urate oxidase in linkage group i of aspergillus nidulans. this gene has been cloned by transformation of a uaz- null mutant. a chromosome i/viii translocation which splits the gene has been defined both genetically and physically. all known mutations are contained in a 1-kb fragment, itself contained in the probe which recognizes a 1.2-kb inducible message. plasmids carrying uaz show a strict bias towards ...19938224862
heterologous protein secretion directed by a repressible acid phosphatase system of aspergillus niger.a new expression-secretion system of aspergillus niger which directs the secretion of heterologous proteins is described. the promoter and signal peptide-encoding region of the phosphate-repressible apha gene of a. niger, when fused to the coding region of the human interferon alpha 2 (hifn alpha 2)-encoding gene (hifn alpha 2), drives the expression of this gene and the secretion of the hifn alpha 2 protein. synthesis of hifn alpha 2 in either a. niger or a. nidulans transformants carrying thes ...19938224863
a novel phage lambda replacement cre-lox vector that has automatic subcloning capabilities.we have developed a novel phage lambda replacement cloning vector, lambda pan. lambda pan allows one to automatically subclone the insert as a plasmid using the cre-loxp site-specific recombination system. this eliminates the need to subclone insert fragments and permits the rapid structural analysis of insert dna. lambda pan is similar to other phage lambda replacement vectors taking inserts ranging in size from 5 to 19 kb. we have placed the pyrg gene of aspergillus nidulans on the vector as a ...19938224901
sequence and regulation of the uapa gene encoding a uric acid-xanthine permease in the fungus aspergillus nidulans.the nucleotide sequence of the uapa gene, coding for the uric acid-xanthine permease of aspergillus nidulans, has been determined. the predicted uapa gene product comprises 595 amino acids (m(r) 63,365); it is a highly hydrophobic protein with 12-14 putative transmembrane segments and shows no striking similarity to any other membrane protein of either prokaryotes or eukaryotes, except for a short highly hydrophobic amino acid sequence conserved in a number of different permeases. the presence o ...19938226862
sequence, regulation, and mutational analysis of the gene encoding urate oxidase in aspergillus nidulans.the uaz gene of aspergillus nidulans codes for a protein of 301 amino acids. the open reading frame is interrupted by two introns. a comparison with the open reading frames of 10 other urate oxidases reveals a number of scattered universally conserved residues and four clusters of high similarity. two of these are of unknown function, and the other two are the putative sites for copper binding and the signal sequence for peroxisomal entry, respectively. this comparison also reveals that there ar ...19938226863
molecular characterization of a fungal secondary metabolism promoter: transcription of the aspergillus nidulans isopenicillin n synthetase gene is modulated by upstream negative elements.the aspergillus nidulans ipns gene, encoding isopenicillin n synthetase, is a secondary metabolism gene. it is contiguous to, but divergently transcribed from, the acvs gene at the penicillin gene cluster. the untranslated region between both orfs is 872bp long. here we present the physical and functional characterization of the ipns transcriptional unit. transcriptional start point (tsp) mapping reveals heterogeneity at the 5'-end of the mrna, with a major start at -106 relative to the initiati ...19938231816
brushing up on bristles: complex genes and morphogenesis in molds. 19938236455
arabinan degrading enzymes from aspergillus nidulans: induction and purification.the presence in aspergillus nidulans of two enzymes related to the aspergillus niger endo-arabinase and alpha-l-arabinofuranosidase b has been established using antibodies against the purified a. niger enzymes. moreover, the absence of an equivalent in a. nidulans to the alpha-l-arabinofuranosidase a of a. niger has been confirmed both at the protein and at the dna level. both a. nidulans arabinases have been purified and physico-chemically and kinetically characterized. they have a much higher ...19938243977
comparative studies on o-acetylhomoserine sulfhydrylase: physiological role and characterization of the aspergillus nidulans enzyme.o-acetylhomoserine sulfhydrylase (oah shlase) from aspergillus nidulans is an oligomeric protein with a broad substrate specificity with regard to sulfhydryl compounds. as its saccharomyces cerevisiae counterpart the enzyme also reacts with o-acetylserine and is inhibited by carbonyl reagents but not by antiserum raised against the yeast enzyme. in contrast to saccharomyces cerevisiae the enzyme is not essential for aspergillus nidulans as indicated by the completely prototrophic phenotype of oa ...19938249501
regulation of sulfur and nitrogen metabolism in filamentous fungi.in the filamentous fungi, n. crassa and a. nidulans, complex regulatory circuits control nitrogen metabolism and sulfur metabolism. the expression of entire sets of unlinked structural genes that encode metabolic enzymes is repressed when favored sulfur or nitrogen sources are available. these structural genes are coregulated by global positive-acting regulatory proteins and often are also controlled by metabolic inducers and pathway-specific regulatory proteins. the recent isolation of regulato ...19938257101
characterization of the 3-dehydroquinase domain of the pentafunctional arom protein, and the quinate dehydrogenase from aspergillus nidulans, and the overproduction of the type ii 3-dehydroquinase from neurospora crassa.the arom protein of aspergillus nidulans is a multidomain pentafunctional polypeptide that is active as a dimer and catalyses steps 2-6 in the prechorismate section of the shikimate pathway. the three c-terminal domains (including the type i 3-dehydroquinase) of the arom protein are homologous with the qutr-encoded qutr protein that represses transcription of the eight genes comprising the quinic acid utilization (qut) gene cluster, and the two n-terminal domains are homologous with the quta-enc ...19938257437
kinetic studies of nitrite uptake by aspergillus nidulans.1. in the filamentous mold aspergillus nidulans, net nitrite uptake is inducible by nitrate and nitrite, is probably different from the nitrate uptake system and is partially repressed by ammonium. 2. the concentration dependence of net nitrite uptake by the bia1 faca303 strain of a. nidulans shows a saturation kinetics with an apparent km value of 0.64 mm. 3. strains of a. nidulans carrying the niha1 and niha1 chla14 mutations considerably reduced the affinity of the nitrite uptake system for t ...19938257915
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
identification of 21 novel human protein kinases, including 3 members of a family related to the cell cycle regulator nima of aspergillus nidulans.the nima gene encodes a protein-serine/threonine kinase that is required along with the p34cdc2 kinase for mitosis in aspergillus nidulans. we have searched for human protein kinases that are related to the nima protein kinase using the polymerase chain reaction. different pairs of degenerate oligonucleotides specific for conserved amino acid motifs in the catalytic domain of nima were used as primers in the polymerase chain reaction to amplify partial complementary dnas (cdnas) of protein kinas ...19938274451
purification and characterization of glucose-6-phosphate dehydrogenase from aspergillus niger and aspergillus nidulans.glucose-6-phosphate dehydrogenase (g6pd; d-glucose 6-phosphate:nadp+ oxidoreductase, ec 1.1.1.49) has been purified from aspergillus nidulans and aspergillus niger by a combination of affinity and anion exchange chromatography. a 500-1000-fold purification was obtained and the final enzyme preparations were shown to be pure but not homogeneous. for both fungi the purified enzyme preparation gave two bands on native and denaturing gels. the catalytically active form is a multimer. the molecular m ...19938277259
sulfur amino acid metabolism and its regulation in fungi: studies with aspergillus nidulans. 19938140816
the macronuclear gamma-tubulin-encoding gene of euplotes octocarinatus contains two introns and an in-frame tga.the gamma-tubulin (gamma-tub)-encoding gene (gamma-tub) of euplotes octocarinatus was amplified from macronuclear dna with the help of the polymerase chain reaction (pcr) and sequenced. the polypeptide deduced from the gene consists of 462 amino acids (aa). it shares 61% aa identity with the aspergillus nidulans gamma-tub. the gene contains an in-frame tga codon and two small pre-mrna introns (36 and 26 bp). we suggest that the tga, like tga codons in the pheromone-encoding genes of e. octocarin ...19938294024
genesis of eukaryotic transcriptional activator and repressor proteins by splitting a multidomain anabolic enzyme.the genes necessary for the correctly regulated catabolism of quinate in aspergillus nidulans and neurospora crassa are controlled at the level of transcription by a dna-binding activator protein and a repressor protein that directly interact with one another. the repressor protein is homologous throughout its length with the three c-terminal domains of a pentafunctional enzyme catalysing five consecutive steps in the related anabolic shikimate pathway. we now report that the activator protein i ...19938294040
molecular organization of the escherichia coli gab cluster: nucleotide sequence of the structural genes gabd and gabp and expression of the gaba permease gene.we have determined the nucleotide sequences of two structural genes of the escherichia coli gab cluster, which encodes the enzymes of the 4-aminobutyrate degradation pathway: gabd, coding for succinic semialdehyde dehydrogenase (ssdh, ec 1.2.1.16) and gabp, coding for the 4-aminobutyrate (gaba) transport carrier (gaba permease). we have previously reported the nucleotide sequence of the third structural gene of the cluster, gabt, coding for glutamate: succinic semialdehyde transaminase (ec 2.6.1 ...19938297211
induction of glucose oxidase, catalase, and lactonase in aspergillus niger.the induction of glucose oxidase, catalase, and lactonase activities was studied both in wild-type and in glucose oxidase regulatory and structural mutants of aspergillus niger. the structural gene for glucose oxidase was isolated and used for northern analysis and in transformation experiments using various gox mutations. wild-type phenotype could be restored in the glucose oxidase-negative mutant (goxc) by transformation with the structural gene. we conclude, therefore, that the goxc marker wh ...19938299156
co-transformation with autonomously-replicating helper plasmids facilitates gene cloning from an aspergillus nidulans gene library.autonomously-replicating, marker-less "helper" plasmids were added to transformations of aspergillus nidulans with plasmids which normally transform by chromosomal integration. this resulted in as much as a 200-fold increase in transformation efficiency. recovery of autonomously-replicating plasmid co-integrates indicated that co-transformation involves recombination between integrating and helper plasmids, which occurs at a high frequency. increasing dna sequence-homology between pairs of plasm ...19938299174
cloning and characterization of the abfb gene coding for the major alpha-l-arabinofuranosidase (abf b) of aspergillus niger.based on amino-acid sequence data from aspergillus niger alpha-l-arabinofuranosidase b (abf b), and cyanogen bromide fragments derived thereof, deoxyoligonucleotide mixtures were designed to be employed as primers in a polymerase chain reaction (pcr) on a. niger genomic dna. this resulted in amplification of three related pcr products. the abfb gene encoding abf b was isolated from a genomic library using such an amplification product as a probe. a 5.1-kb bamhi fragment was subcloned to result i ...19938299175
evidence for a multi-allelic heterokaryon incompatibility (het) locus detected by hybridization among three heterokaryon-compatibility (h-c) groups of aspergillus nidulans.a strain of heterokaryon-compatibility (h-c) group a was crossed sexually to strains of h-cb and h-cgl of aspergillus nidulans. a back-crossing programme established that there were seven hetero-allelic heterokaryon compatibility (het) genes controlling somatic incompatibility between strains of h-ca and h-cb. a similar back-crossing programme between strains of h-ca and h-cgl confirmed that these two groups differ at six het loci. previous work has shown that h-cb differs from h-cgl at two het ...19938314715
spatial and temporal controls of the aspergillus brla developmental regulatory gene.the aspergillus nidulans brla gene encodes a transcriptional regulator of central importance in controlling conidiophore development. i have determined the effects of mutations in other developmental regulatory genes on expression of a brla-lacz fusion gene. deletion of brla reduced beta-galactosidase levels by half and led to delocalization of enzyme accumulation. the meda26 and abaa2 developmental mutations led to overexpression of the fusion gene without altering spatial specificity. in contr ...19938316075
choline: its role in the growth of filamentous fungi and the regulation of mycelial morphology.choline is an essential metabolite for the growth of filamentous fungi. it occurs most notably as a component of the major membrane phospholipid, phosphatidyl choline (lecithin), and fulfills a major role in sulphate metabolism in the form of choline-o-sulphate in many species. choline is usually synthesised endogenously, but exogenous choline can also be taken up, either to compensate for metabolic deficiencies in choline-requiring mutants such as those of aspergillus nidulans and neurospora cr ...19938318261
isolation and nucleotide sequence of the 5-aminolevulinate synthase gene from aspergillus nidulans.the structural gene for 5-aminolevulinate (ala) synthase has been cloned and sequenced from the filamentous fungus aspergillus nidulans using an oligonucleotide probe based on a highly conserved-amino-acid sequence found in ala synthase genes of a wide range of species. the cloned gene, hema, has a 5' untranslated mrna of 92 nucleotides (nt) and one intron (64 nt). the deduced protein sequence (648 amino acids) shows 64% identity to the yeast ala synthase in the c-terminal region of 453 amino ac ...19938319309
complement binding to aspergillus conidia correlates with pathogenicity.complement has significant effects on the phagocytosis of aspergillus organisms. we examined the amount and type of complement component c3 bound to the resting conidia of 29 isolates from nine aspergillus species. the highly pathogenic species a. fumigatus and a. flavus bound fewer c3 molecules per unit of conidial surface area than did the less pathogenic species a. glaucus, a. nidulans, a. niger, a. ochraceus, a. terreus, a. versicolor, and a. wentii, as determined by quantitative flow cytome ...19938320488
the isolation of mutagen-sensitive nuv mutants of aspergillus nidulans and their effects on mitotic recombination.more than 200 mutants of aspergillus nidulans were isolated as hypersensitive to the monofunctional alkylating agent mnng and/or uv-irradiation (designated nuv mutants). of these, 23 were selected for further characterization. all were markedly hypersensitive to both mnng and the quasi-uv-mimetic mutagen 4-nqo. the hypersensitive phenotype of each mutant was shown to result from mutation of a single gene. the nuv mutants exhibited a diverse range of growth responses on solid media containing var ...19938325481
either alpha-tubulin isogene product is sufficient for microtubule function during all stages of growth and differentiation in aspergillus nidulans.the filamentous fungus aspergillus nidulans has two genes encoding alpha-tubulin, tuba and tubb, which are differentially required at distinct stages during the life cycle. the tuba gene is required during vegetative growth for mitosis and nuclear migration (b. r. oakley, c. e. oakley, and j. e. rinehart, mol. gen. genet. 208:135-144, 1987; p. doshi, c. a. bossie, j. h. doonan, g. s. may, and n. r. morris, mol. gen. genet. 225:129-141, 1991). the tubb gene is not required for any detectable aspe ...19938336695
uvsi mutants defective in uv mutagenesis define a fourth epistatic group of uvs genes in aspergillus.three uv-sensitive mutations of a. nidulans, uvsi, uvsj and uvsa, were tested for epistatic relationships with members of the previously established groups, here called the "uvsf", "uvsc", and "uvsb" groups. uvsi mutants are defective for spontaneous and induced reversion of certain point mutations and differ also for other properties from previously analyzed uvs types. they are very sensitive to the killing effects of uv-light and 4-nqo (4-nitro-quinoline-n-oxide) but not to mms (methylmethane ...19938358834
the aspergillus niger carbon catabolite repressor encoding gene, crea.in order to undertake a comparative analysis of carbon catabolite repression in two aspergillus species, the crea gene has been isolated from a. niger by cross hybridization, using the cloned a. nidulans gene. the a. niger gene has been shown to be functional in a. nidulans by heterologous complementation of the crea204 mutation of a. nidulans. overall, the genes show 90% sequence similarity (82% identity) at the amino acid (aa) level. there were some striking similarities between the aa sequenc ...19938359691
characterization of the pyruvate kinase-encoding gene (pki1) of trichoderma reesei.the pyruvate kinase-encoding gene (pki1) from trichoderma reesei was isolated by hybridization to the corresponding aspergillus nidulans pkia gene. the 1614-bp nucleotide (nt) sequence of the cloned gene codes for a 538-amino-acid protein. the coding sequence contains a single intron of 246 nt at a position identical to that of intron e in the a. nidulans gene. the pki protein shows extensive homology to the pkis of a. nidulans and a. niger (67%) and saccharomyces cerevisiae (59%). the 5' non-co ...19938359694
the gamma-tubulin gene of the malaria parasite plasmodium falciparum.by screening of cdna and genomic libraries of plasmodium falciparum with a dna probe derived from the cognate beta-tubulin gene, gene pf gamma tub has been identified that codes for gamma-tubulin, a newly discovered member of the tubulin superfamily that is indispensible for nuclear division and microtubule assembly [12]. gene pf gamma tub is not interrupted by introns and only present as a single-copy in the parasite genome. its encoded amino acid sequence (452 amino acids; m(r) 50,560) has a 6 ...19938366893
the nia gene of fusarium oxysporum: isolation, sequence and development of a homologous transformation system.the fusarium oxysporum gene nia, encoding nitrate reductase (nr), was isolated from a cosmid library by direct complementation of an f. oxysporum nia- mutant. the gene specifies a protein of 905 amino acids and contains a 57-bp intron. comparison of the deduced aa sequence with nr of other fungi revealed a high degree of similarity and conservation in the intron position. the cloned nia made it possible to develop the first homologous transformation system for this fungus. transformation frequen ...19938370541
analysis of heterokaryon incompatibility between heterokaryon-compatibility (h-c) groups r and gl provides evidence that at least eight het loci control somatic incompatibility in aspergillus nidulans.protoplast fusion was used to hybridize strains 99-6 (h-cr) and 7-141 (h-cgl) in the birmingham collection of aspergillus nidulans. a sparsely conidiating, brown-pigmented diploid strain (ma7) was isolated. inocula from ma7 were haploidized on medium containing benlate and a haploid progeny sample collected. heterokaryon compatibility testing of selected progeny strains assayed each linkage group in turn and established that h-cr and h-cgl were hetero-allelic for heterokaryon incompatibility (he ...19938371120
mutation in the bimd gene of aspergillus nidulans confers a conditional mitotic block and sensitivity to dna damaging agents.mutation in the bimd gene of aspergillus nidulans results in a mitotic block in anaphase characterized by a defective mitosis. mutation in bimd also confers, at temperatures permissive for the mitotic arrest phenotype, an increased sensitivity to dna damaging agents, including methyl methanesulfonate and ultraviolet light. in order to better understand the relationship between dna damage and mitotic progression, we cloned the bimd gene from aspergillus. a cosmid containing the bimd gene was iden ...19938375649
quantitative structure-activity relationship models correctly predict the toxic and aneuploidizing properties of six halogenated methanes in aspergillus nidulans.in a previous study, the relationships between the chemical structure and the ability of 35 chlorinated aliphatic hydrocarbons to induce aneuploidy and toxicity in aspergillus nidulans were analyzed. quantitative structure-activity relationships (qsar) were defined for each of the biological activities under study: arr (the dose able to block mitotic growth), d37 (the dose with 37% of survival) and lec (the lowest efficient concentration in aneuploidy induction). in this study, these qsar equati ...19938377647
development of a transformation system for the filamentous, ml-236b (compactin)--producing fungus penicillium citrinum.we present here the first report of a transformation system developed for the filamentous, ml-236b (compactin)-producing fungus penicillium citrinum. hygromycin b-resistant colonies were obtained after treatment of protoplasts with a vector containing an escherichia coli hygromycin b phosphotransferase gene fused to a 3-phosphoglycerate kinase promoter from aspergillus nidulans. the transformation rate was 194 transformants per microgram circular dna per 4 x 10(5) viable protoplasts under optimi ...19938381335
the molecular biology of the pentafunctional arom protein. 19938383607
overproduction of, and interaction within, bifunctional domains from the amino- and carboxy-termini of the pentafunctional arom protein of aspergillus nidulans.the pentafunctional arom protein in aspergillus nidulans and other fungi catalyses five consecutive enzymatic steps leading to the production of 5-enolpyruvylshikimate 3-phosphate (epsp) in the shikimate pathway. the arom protein has five separate enzymatic domains that have previously been shown to display a range of abilities to fold and function in isolation as monofunctional enzymes. in this communication, we report (1) the stable overproduction of a bifunctional protein containing the 3-deh ...19938393515
ph regulation is a major determinant in expression of a fungal penicillin biosynthetic gene.transcription of the ipna gene encoding isopenicillin n synthetase, an enzyme of secondary metabolism, is under the control of the ph regulatory system in the fungus aspergillus nidulans. external alkaline ph or mutations in pacc, the wide domain regulatory gene which mediates ph regulation, override carbon regulation of ipna transcript levels, resulting in elevation of the levels of this message in sucrose broth. strains carrying these mutations, which mimic growth at alkaline ph, produce highe ...19938404862
purification and molecular properties of an alpha-galactosidase synthesized and secreted by aspergillus nidulans.alpha-galactosidases from mycelial extract and culture filtrate of aspergillus nidulans have been purified to homogeneity and utilised to obtain polyclonal antibodies anti-alpha-galactosidase. the enzymatic characteristics and the cross reactivity of the antibodies suggest that alpha-galactosidases isolated from the two sources were the same enzyme. thus, a. nidulans synthesized and secreted only one enzymatic form of alpha-galactosidase which is a multimeric enzyme of 370 kda composed of four m ...19938405947
biochemical characterization and molecular genetics of nine mutants of penicillium chrysogenum impaired in penicillin biosynthesis.nine mutants of penicillium chrysogenum (npe1 to npe8 and npe10) impaired in penicillin biosynthesis were screened after nitrosoguanidine mutation. mutants npe1, npe4, npe5, npe6, npe7, npe8, and npe10 failed to synthesize significant levels of penicillin, whereas strains npe2 and npe3 synthesized about 20% of the penicillin level produced by the parental strain. mutants npe5 and npe10 did not show alpha-aminoadipylcysteinyl-valine (acv) synthetase activity in vitro and did not form acv in vivo. ...19938416976
functional redundancy in mitotic force generation. 19938416980
suppression of the bimc4 mitotic spindle defect by deletion of klpa, a gene encoding a kar3-related kinesin-like protein in aspergillus nidulans.to investigate the relationship between structure and function of kinesin-like proteins, we have identified by polymerase chain reaction (pcr) a new kinesin-like protein in the filamentous fungus aspergillus nidulans, which we have designated klpa. dna sequence analysis showed that the predicted klpa protein contains a cooh terminal kinesin-like motor domain. despite the structural similarity of klpa to the kar3 and ncd kinesin-like proteins of saccharomyces cerevisiae and drosophila melanogaste ...19938416986
identification of aspergillus brla response elements (bres) by genetic selection in yeast.the brla gene of aspergillus nidulans plays a central role in controlling conidiophore development. to test the hypothesis that brla encodes a transcriptional regulator and to identify sites of interaction for the brla polypeptide, we expressed brla in saccharomyces cerevisiae (yeast) strains containing aspergillus dna sequences inserted upstream of a minimal yeast promoter fused to the escherichia coli lacz gene. initially, a dna fragment from the promoter region of the developmentally regulate ...19938417986
genetic maps of eight linkage groups of aspergillus niger based on mitotic mapping.this paper provides a genetic map of aspergillus niger. at present 84 markers have been assigned to eight linkage groups. the chromosomal location of 60 markers is presented in this paper. the allocation of markers is based on recombination due to mitotic crossing over. various methods for selection and analysis of homozygous recombinants were applied, using colour, auxotrophic and resistance markers. in addition, transformants carrying the heterologous aspergillus nidulans gene coding for aceta ...19938428383
disruption of the 3' phosphoglycerate kinase (pgk) gene in aspergillus nidulans.we report the isolation of a pgk- mutant strain of aspergillus nidulans by means of a gene disruption strategy, and demonstrate that the pgk gene is located on chromosome viii. the pgk- mutant conidiates poorly, will only grow on media supplemented with both a glycolytic and a gluconeogenic carbon source, and is inhibited by hexoses.19938431952
cloning and sequencing of the 3-phosphoglycerate kinase (pgk) gene from penicillium citrinum and its application to heterologous gene expression.the gene coding for 3-phosphoglycerate kinase (pgk) in ml-236b (compactin)-producing penicillium citrinum was isolated from the recombinant phage lambda library using the corresponding aspergillus nidulans pgk gene as a probe. the p. citrinum pgk gene has an open reading frame of 1,254 bp, encoding a protein of 417 amino acids with a predicted molecular weight of 44,079 daltons. the position of the two introns, 59 and 60 bp respectively, was deduced from an homology comparison with the sequence ...19938431954
bima, a tpr-containing protein required for mitosis, localizes to the spindle pole body in aspergillus nidulans.the aspergillus nidulans bima gene is required for mitosis. loss of function mutations in bima cause cells to arrest growth with condensed chromatin and a short, metaphaselike mitotic spindle. bima is a member of a gene family defined by a repeated motif called the tetratrico peptide repeat (tpr), which is found in genes from bacteria, yeast and insects. several yeast tpr genes are also required for mitosis, including saccharomyces cerevisiae cdc27 and schizosaccharomyces pombe nuc2+, which appe ...19938432735
c-terminal truncation of the transcriptional activator encoded by area in aspergillus nidulans results in both loss-of-function and gain-of-function phenotypes.mutations truncating as many as 143 c-terminal residues from the transcriptional activator encoded by the area gene, mediating nitrogen metabolite repression in aspergillus nidulans, do not significantly reduce the ability of the area product to activate expression of most genes under area control. such mutations can even have a gain-of-function, derepressed phenotype, consistent with a critical role for this region in modulating the activity of the area protein. however, expression of a few gen ...19938437521
operator derepressed mutations in the proline utilisation gene cluster of aspergillus nidulans.the proline utilisation gene cluster of aspergillus nidulans can be repressed efficiently only when both repressing nitrogen and repressing carbon sources are present. we show that two cis-acting mutations in this cluster permit the efficient transcription of the prnb gene under repressing conditions, resulting in direct or indirect derepression of two other transcripts of the pathway. these mutations are transitions that define a 5'gagacccc3' sequence. similar sequences are found upstream of ot ...19938437566
cloning of two isozymes of trichoderma koningii glyceraldehyde-3-phosphate dehydrogenase with different sensitivity to koningic acid.koningic acid inhibits glyceraldehyde-3-phosphate dehydrogenase (gapdh) by binding to the sh group in the active center. the fungus trichoderma koningii, the producer of koningic acid, contains two gapdh isozymes (gapdhs i and ii). gapdh i is inhibited 50% by 1.1.10(-3) m koningic acid, while gapdh ii is inhibited 50% at 6.8 x 10(-6) m. cdnas of the two isozymes were cloned from t. koningii and their nucleotide sequences were determined. the sequence of coding region and codon usage in both clon ...19938439569
molecular cloning and analysis of abundant and stage-specific mrnas from puccinia graminis.to characterize highly expressed mrnas from germinated urediniospores of puccinia graminis f. sp. tritici, we isolated 68 cdna clones of abundant mrna species belonging to at least six homology groups. the two most abundant homology groups, hg1 and hg2, contained 54 of the 68 cdna clones and accounted for 2.4 and 0.6% of the poly(a)+ rna in germinated urediniospores, respectively. by sampling different developmental stages of the uredinial cycle, we showed that the uam transcript, corresponding ...19938439672
the mitochondrial genome of the entomopathogenic fungus beauveria bassiana: analysis of the ribosomal rna region.the 28.5-kbp mitochondrial (mt) genome from the entomopathogenic fungus beauveria bassiana was studied using restriction enzyme analysis, gene probe hybridization, and dna sequence comparisons. a detailed restriction enzyme map allowed cloning of the entire genome into a number of segments. hybridization of heterologous gene probes to the mtdna resulted in the identification of the large ribosomal rna (lrrna) and small ribosomal rna (srrna) genes. gene probes derived from several yeasts and fung ...19938439871
cerato-ulmin, a toxin involved in dutch elm disease, is a fungal hydrophobin. 19938453298
aspergillus nidulans nuclear proteins bind to a ccaat element and the adjacent upstream sequence in the promoter region of the starch-inducible taka-amylase a gene.aspergillus nidulans was used as an intermediate host to investigate the regulation of the taka-amylase a (taa) gene from aspergillus oryzae. the induction of taa by starch was confirmed to be regulated at the transcriptional level by analyzing the transcripts specific for taa synthesized in vitro in nuclei from starch- and glucose-grown cells. a 55 bp dna fragment containing a consensus ccaat sequence from the promoter region of the taa gene was shown to confer starch inducibility on the gene. ...19938455560
evolutionary conservation of excision repair in schizosaccharomyces pombe: evidence for a family of sequences related to the saccharomyces cerevisiae rad2 gene.cells mutated at the rad13 locus in the fission yeast, schizosaccharomyces pombe are deficient in excision-repair of uv damage. we have cloned the s.pombe rad13 gene by its ability to complement the uv sensitivity of a rad13 mutant. the gene is not essential for cell proliferation. sequence analysis of the cloned gene revealed an open reading-frame of 1113 amino acids with structural homology to the rad2 gene of the distantly related saccharomyces cerevisiae. the sequence similarity is confined ...19938464724
carnitine acetyltransferase is absent from acuj mutants of aspergillus nidulans.the acuj mutant of aspergillus nidulans has been shown to lack carnitine acetyltransferase (cat) activity when grown under conditions where this activity is readily detectable in wild-type strains. revertants selected for growth on acetate recover cat activity and the ability to grow on long-chain fatty acids. when growing on carbon sources such as sucrose, cytosolic acetyl coenzyme a was generated by adenosine triphosphate (atp):citrate lyase.19938472927
properties and regulation of the cell cycle-specific nima protein kinase of aspergillus nidulans.nima is the protein product of the nima gene of the filamentous fungus aspergillus nidulans, required for progression of cells from g2 into mitosis. the protein kinase activity of nima, assayed by phosphorylation of beta-casein, varies during the nuclear division cycle, reaching a maximum in late g2 and m. to investigate the biochemical properties of this cell cycle-regulated protein kinase, we have expressed nima cdna that encodes full-length nima in escherichia coli as a fusion product with gl ...19938473320
properties of genes involved in the control of isocitrate lyase production in aspergillus nidulans.the interaction between genes of aspergillus nidulans conferring constitutive synthesis of isocitrate lyase (iclc a and iclcb) and fluoroacetate resistance (facb) has been investigated. although facb mutants are unable to induce the glyoxylate cycle enzyme isocitrate lyase in response to acetate as sole carbon source, this phenotype was suppressed in recombinants of the type iclc;facb. the iclca and iclcb mutations do not alter significantly the activities of eight enzymes of intermediary metabo ...19938473860
at least four regulatory genes control sulphur metabolite repression in aspergillus nidulans.mutations in four genes: scona (formerly sua25meth, mapa25), sconb (formerly mapb1), sconc and scond, the last two identified in this work, relieve a group of sulphur amino acid biosynthetic enzymes from methionine-mediated sulphur metabolite repression. exogenous methionine has no effect on sulphate assimilation in the mutant strains, whereas in the wild type it causes almost complete elimination of sulphate incorporation. in both mutant and wild-type strains methionine is efficiently taken up ...19938479426
specific binding sites in the alcr and alca promoters of the ethanol regulon for the crea repressor mediating carbon catabolite repression in aspergillus nidulans.the crea repressor responsible for carbon catabolite repression in aspergillus nidulans represses the transcription of the ethanol regulon. the n-terminal part of the crea protein encompassing the two zinc fingers (c2h2 class family) and an alanine-rich region was expressed in escherichia coli as a fusion protein with glutathione-s-transferase. our results show that crea is a dna-binding protein able to bind to the promoters of both the specific trans-acting gene, alcr, and of the structural gen ...19938483416
essential roles for calcium and calmodulin in g2/m progression in aspergillus nidulans.nimt encodes a protein in aspergillus nidulans that is required for tyrosine dephosphorylation of p34cdc2 and has a strong homology to cdc25-type proteins. conditional mutation of nimt (nimt23 mutation) arrests cells in g2 at the restrictive temperature. after release of the temperature-sensitive nimt23 block, p34cdc2 undergoes tyrosine dephosphorylation and we showed that as cells entered mitosis, a rapid increase in calmodulin was observed. the increase in calmodulin and progression into mitos ...19938486741
the aspergillus nidulans ya gene is regulated by abaa.the developmentally regulated aspergillus nidulans ya gene encodes a p-diphenol oxidase that is needed for synthesis of green conidial pigment. we subjected the ya 5' flanking region to mutational analysis in a. nidulans and saccharomyces cerevisiae to identify dna sequence elements involved in its transcriptional control, and identified two functionally distinct elements. element i contained potential brla binding sites and was required for full level ya transcription, but not for developmental ...19938491194
the aspergillus nidulans brla regulatory locus consists of overlapping transcription units that are individually required for conidiophore development.the aspergillus nidulans brla locus controls conidiophore development in conjunction with the products of several other regulatory loci. in this paper, we show that the brla locus consists of overlapping transcription units, designated alpha and beta, with alpha transcription initiating within beta intronic sequences. the predicted brla polypeptides differ by 23 amino acid residues at their n-termini. targeted mutations specifically eliminating either the alpha or beta transcript led to developm ...19938508769
translational repression of brla expression prevents premature development in aspergillus.the aspergillus nidulans brla developmental regulatory locus consists of two overlapping transcription units, brla alpha and brla beta, which encode functionally related polypeptides. we used translational fusions between each of the predicted brla reading frames and the escherichia coli lacz gene to test the hypothesis that developmental regulation of brla alpha and brla beta expression occurs through different mechanisms. brla alpha is transcriptionally controlled and a large portion of brla a ...19938508770
estimation of mitotic stability in conidial fungi: a theoretical framework.mitotic stability refers to the probability that genetic elements are transmitted to both daughters during mitosis. this is of practical importance in molecular genetics because autonomous cloning vectors should be transmitted at high frequency during mitosis. in filamentous coencytic fungi it is difficult to quantify mitotic stability because a fluctuation test is not feasible. we show how to get around this problem by formulating a general model of the transmission of nuclear genetic elements ...19938514143
characterisation of the gene encoding acetyl-coa synthetase in penicillium chrysogenum: conservation of intron position in plectomycetes.acetyl-coenzyme a synthetase (acs; ec 6.2.1.1) from some plectomycete fungi is possibly involved in an accessory step of penicillin biosynthesis, in addition to its role in primary metabolism. we present the characterisation of the gene encoding this enzyme in penicillium chrysogenum, which we designated acua. sequencing of genomic and cdna clones showed that the coding region was interrupted by five introns, located at the same positions as those present in the aspergillus nidulans homologue. t ...19938103029
isolation and characterization of β-glucosidases from aspergillus nidulans mutant usdb 1183.two extracellular β-glucosidases (cellobiase, ec 3.2.1.21), i and ii, from aspergillus nidulans usdb 1183 were purified to homogeneity with molecular weights of 240,000 and 78,000, respectively. both hydrolysed laminaribiose, β-gentiobiose, cellobiose, p-nitrophenyl-β-l-glucoside, phenyl-β-l-glucoside, o-nitrophenyl-β-l-glucoside, salicin and methyl-β-l-glucoside but not α-linked disaccharides. both were competitively inhibited by glucose and non-competitively (mixed) inhibited by glucono-1,5-la ...199324420198
expression of fungal genes involved in penicllin biosynthesis.carbon catabolite repression and ph regulation are regulatory circuits with a wide domain of action in the plectomycetes. penicillin biosynthesis is one of the pathways which are under their control. the conclusions obtained so far, which are based on studies of the genetic and molecular regulation of the penicillin pathway of aspergillus nidulans, would have been much harder to produce using an organism such as penicillium chrysogenum (the industrial penicillin producer). however, a. nidulans a ...199324420113
phytotoxic and antimicrobial activity of volatile constituents ofartemisia princeps var.orientalis.the volatile constituents ofartemisia princeps var.orientalis (wormwood) were investigated for phytotoxic and antimicrobial activities. the germination and radicle elongation of receptor plants were inhibited by volatile substances emitted from wormwood leaf and effects were concentration-dependent. essential oil of the plant extracted by karlsruker's apparatus suppressed seed germination and seedling elongation of the receptor plants at a threshold concentration of 4.8μl/100 ml.escherichia coli ...199324248725
kinetics of cell growth and heterologous glucoamylase production in recombinant aspergillus nidulans.in the work, a study of cell growth and the regulation of heterologous glucoamylase synthesis under the control of the positively regulated alca promoter in a recombinant aspergillus nidulans is presented. we found that similar growth rates were obtained for both the host and recombinant cells when either glucose or fructose was employed as sole carbon and energy source. use of the potent inducer cyclopentanone in concentrations greater than 3 mm resulted n maximum glucoamylase concentration and ...199318609547
symmetric branching model for the kinetics of mycelial growth.a mathematical model, linking microscopic to macroscopic parameters of the kinetics of mycelial growth is presented. the model consists of two parts: (a) a microscopic description, based on the assumption that growth of a mycelium can be represented approximately by the growth of a symmetric binary tree, where the branching level (microscopic state variable) is logarithmically related to the number of tips and segments; and (b) a macroscopic description which makes use of the microscopic descrip ...199318609641
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