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defective splicing of mitochondrial rrna in cytochrome-deficient nuclear mutants of neurospora crassa.recent studies have shown that the gene encoding the large (25 s) mitochondrial rrna of neurospora crassa contains an intervening sequence of 2-2.5 kilobases that is not present in the mature 25s mitochondrial rrna. earlier studies had provided evidence that mitochondrial rrnas in neurospora are synthesized via a 32s precursor rna that contains sequences for both the mature 19s and 25s rna species. the present work shows that the intervening sequence is not present in 32s rna. however, we have i ...1979156923
role of purine base excretion in regulation of purine pools.wild type and mutant strains of neurospora crassa excrete hypoxanthine, xanthine, and uric acid, but not adenine or inosine, when exogenous adenine is added to growing cultures. no detectable excretion occurs in the absence of adenine. the de novo pathway of purine biosynthesis was found to influence the excretion, in that a metabolic block immediately prior to imp significantly decreased the excretion, while a metabolic block immediately after imp significantly increased the excretion over that ...1979157418
[studies on the conidial differentiation of "neurospora crassa" -- vii. -- alcoholic regulation and conidiogenous capacity (wild-type and "fluffy" mutant) (authors transl)].sucrose consumption by the wild-type neurospora crassa is quicker, with much more ethanol produced, in the ammonium medium than in nitrate as single n source. on low sugar concentration which is quickly nullified, little alcohol is produced and early conidiation can develop. the higher the initial sugar concentration, the higher is the alcoholigenic coefficient defined as the efficiency of alcoholic glycolysis per unit of sugar consumed, and the more complete is the conidial "repression" in ammo ...2013157707
competitive inhibition of neurospora crassa chitin synthetase activity by tunicamycin. 1979157718
characterization of the sequence complexity and organization of the neurospora crassa genome. 1979157775
expression of the structural gene for catabolic dehydroquinase of neurospora crassa in escherichia coli k12. 1977157795
the major intracellular alkaline deoxyribonuclease activities expressed in wild-type and rec-like mutants of neurospora crassa.over 95% of the deoxyribonuclease (dnase) activity of log-phase mycelia of neurospora crassa is expressed as single-strand (ss) specific endonucleolytic activity. this activity is associated with three nucleases (d1, d2, and d3) which after partial purification from extracts, express activity with double-strand (ds) dna as well. all three enzymes also degrade rna at approximately the same rates that they degrade ss-dna. d3 has been identified as endoexonuclease, an enzyme previously shown to hav ...1979157796
electron cytochemical detection of two dehydrogenase activities in neurospora crassa. 1979157813
permeability changes in membranes of neurospora crassa after freezing and thawing. 1979157849
circadian rhythms in neurospora crassa: effects of saturated fatty acids.to assess their effects on the conidiation rhythm in neurospora, 14 saturated fatty acids from 6 to 24 carbons long were used to supplement the bd csp and bd csp cel strains. both strains express a circadian spore-forming rhythm when grown on solid media; the cel mutation confers a partial fatty acid requirement. fatty acid supplements from 8 to 13 carbons long lengthened the free-running period of bd csp cel compared with the control value of 21 h; the maximal effect (33 h) was obtained with no ...1979158008
inducible and constitutive kynureninases. control of the inducible enzyme activity by transamination and inhibition of the constitutive enzyme by 3-hydroxyanthranilate.the inducible kynureninase from neurospora crassa is inactivated by incubation with l-alanine or l-ornithine. the inactivated enzyme is resolved to the apoenzyme by dialysis. reactivation of the apoenzyme is achieved by incubation with pyridoxamine 5'-phosphate plus pyruvate, as well as with pyridoxal 5'-phosphate. the kynurenine hydrolysis proceeds linearly in the presence of added pyridoxal 5'-phosphate, or pyridoxamine 5'-phosphate plus pyruvate. these findings indicate that the fungal induci ...1979158014
mitochondrial ribosome assembly in neurospora. two-dimensional gel electrophoretic analysis of mitochondrial ribosomal proteins.recent results with neurospora crassa show that one protein (s-5, mol wt 52,000) associated with the mitochondrial (mit) small ribosomal subunit is translated within the mitochondria (lambowitz et al. 1976. j. mol. biol. 107:223-253). in the present work, neurospora mit ribosomal proteins were analyzed by two-dimensional gel electrophoresis using a modification of the gel system of mets and bogorad. the results show that s-5 is present in near stoichiometric concentrations in high salt (0.5 mkcl ...1979158027
a study of the organisation of the ribosomal ribonucleic acid gene cluster of neurospora crassa by means of restriction endonuclease analysis and cloning in bacteriophage lambda.1. total neurospora crassa dna was restricted with endonucleases and fragments carrying rrna coding sequences were identified by hybridization with xenopus laevis ribosomal dna probes. 2. the repeating unit of the rrna gene cluster was found to be 8.6 kbp, arranged in a head-to-tail fashion. 3. digestion with hind iii yielded fragments of 3.4 kbp and 5.2 kbp and both were cloned. 4. digestion with eco ri yielded fragments of 2.2 kbp, 3.0 kbp and 3.4 kbp; the 3.0 kbp fragment was cloned. 5. seque ...1979158122
metabolic activations of dimethylnitrosamine by male and female mice and rats to metabolites mutagenic in neurospora crassa. 1979158139
level and turnover of polyadenylate-containing ribonucleic acid in neurospora crassa in different steady states of growth.mycelia of neurospora crassa in a steady state of growth in different media have a ribosomal content proportional to the rate of growth. moreover, both the percentage of polysomes and the average ribosomal activity are about the same at all different growth rates. the content of polyadenylated rna was determined in three different conditions of exponential growth, which allowed growth rates that ranged from 0.26 to 0.51 duplications/h, and was found to constitute about the same fraction of total ...1979158528
rapid rna sequencing: nucleases from staphylococcus aureus and neurospora crassa discriminate between uridine and cytidine.using end-labelled rna, significant changes in base specificity of three nucleases have been detected under defined conditions. staphylococcus aureus nuclease at ph 3.5 without ca++ cleaves all pyr-n bonds more uniformly and efficiently than rnase a, without any preference for pyr-a bonds. at ph 7.5 in 10 mm ca++ this enzyme cleaves all n-c and n-g bonds slowly, whereas n-u and n-a bonds are hydrolyzed rapidly. hence, the base at the 3'- or at the 5'-side of a phosphodiester bond can determine t ...1979158747
cell-free synthesis of the mitochondrial adp/atp carrier protein of neurospora crassa.adp/atp carrier protein was synthesized in heterologous cell-free systems programmed with neurospora poly(a)-containing rna and homologous cell-free systems from neurospora. the apparent molecular weight of the product obtained in vitro was the same as that of the authentic mitochondrial protein. the primary translation product obtained in reticulocyte lysates starts with formylmethionine when formylated initiator methionyl-trna (fmet-trnafmet) was present. the product synthesized in vitro was r ...1979159174
organization of the qa gene cluster in neurospora crassa: direction of transcription of the qa-3 gene.in neurospora crassa, the enzyme quinate (shikimate) dehydrogenase catalyzes the first reaction in the inducible quinic acid catabolic pathway and is encoded in the qa-3 gene of the qa cluster. in this cluster, the order of genes has been established as qa-1 qa-3 qa-4 qa-2. amino-terminal sequences have been determined for purified quinate dehydrogenase from wild type and from uv-induced revertants in two different qa-3 mutants. these two mutants (m16 and m45) map at opposite ends of the qa-3 lo ...1979159203
mapping and cloning of neurospora crassa mitochondrial transfer rna genes.we have obtained collections of recombinant escherichia coli plasmids containing restriction fragments of neurospora crassa mitochondrial dna cloned into pbr322. by hybridization of 32p end-labeled total mitochondrial trnas and seven different purified trnas to restriction digests of mitochondrial dna and of recombinant plasmids carrying specific restriction fragments, we have located the trna genes on the mitochondrial dna. we have found that the mitochondrial trna genes are present in two majo ...1979159308
efficient transformation of neurospora crassa by utilizing hybrid plasmid dna.an efficient transformation system has been developed for neurospora crassa that uses spheroplasts and pvk88 plasmid dna. pvk88 is a recombinant escherichia coli plasmid carrying the n. crassa qa-2(+) gene which encodes catabolic dehydroquinase (3-dehydroquinate hydro-lyase, ec 4.2.1.10) and is part of the qa gene cluster. the recipient strain carries a stable qa-2(-) mutation and an arom-9(-) mutation, thus lacking both catabolic and biosynthetic dehydroquinase activities. transformants were se ...1979159454
chitin synthase activity from the slime variant of neurospora crassa.chitin synthase (udp-2-acetamido-2-deoxy-d-glucose:chitin 4-beta-acetamidodeoxy-d-glucosyltransferase, ec 2.4.1.16) activity from the wall-less variant of neurospora crassa (slime) was partially characterized. the slime enzyme activity was found to be similar to that reported for slime-like and wild-type chitin synthase activities with respect to the following: specific activity, particulate cell-fraction localization, activation by n-acetylglucosamine, apparent km with respect to substrate, ph ...1979159723
dna-mediated genetic changes in neurospora crassa.evidence for genetic transformation in neurospora crassa is based on the observations that allo-dna has a specific effect in producing transformants which is abolished by dnaase treatment and that iso-dna is not effective in transformation. here, unambiguous evidence for genetic transformation is provided by transfer of a temperature-sensitive inositol requirement from a donor to a recipient strain. data provided also suggest the role of growth conditions and the involvement of a nuclease gene i ...1990159941
role of surface wettability in phagocytosis of neurospora crassa spores. 1979159950
characterization of variant neurospora crassa mitochondrial dnas which contain tandem reiterations.two variant mtdna types ((types iia and hi-10) have been identified in individual subcultures of the extra-nuclear [poky] mutant of neurospora crassa. eco ri digests of type iia mtdna are characterized by an extra band, alpha, mr = 1.4 mdal, which arises from tandemly inserted reiterations of a 1.4 mdal sequence. restriction enzyme analysis and southern hybridization experiments show: that the 1.4 mdal repeats are located at the junction of eco ri-4 and -6, that the repeats contain sequences ord ...1979160287
biosynthesis of mitochondrial citrate synthase in neurospora crassa. 1979160336
purification and chemical characterization of the rodlet layer of neurospora crassa conidia.the rodlet layer of neurospora crassa macroconidia has been purified and chemically characterized. sheets of rodlets were released from the conidial surface by vigorously shaking conidia in water. conidia were removed by filtration and low-speed centrifugation, and the rodlets were recovered from the supernatant by high-speed centrifugation. the rodlet pellet comprised 1.9% of the initial dry weight. chemical analysis was hampered by the insolubility of the rodlets. they were not solubilized by ...1979160407
isolation of neurospora crassa bradytrophs.a method was developed for the isolation of neurospora bradytrophs. the bradytrophs (representing lesions in a number of pathways) were resistant to dl-p-fluorophenylalanine when growing in a leaky fashion but were sensitive when grown in the presence of their stimulating supplement.1979160410
nitrogen regulation of uricase synthesis in neurospora crassa. 1979160493
increased expression of a eukaryotic gene in escherichia coli through stabilization of its messenger rna.the expression of a cloned eukaryotic gene [catabolic dehydroquinase (3-dehydroquinate hydro-lyase, ec 4.2.1.10) (qa-2+) from neurospora crassa] is dramatically increased (as much as 100-fold) in escherichia coli strains deficient in polynucleotide phosphorylase (pnp) (polynucleotide: orthophosphate nucleotidyltransferase, ec 2.7.7.8) and rnase i (rna). the increased expression is controlled primarily by the absence of polynucleotide phosphorylase and appears to be specific for the eukaryotic ge ...1979160556
a comparative study of dna-induced transformants and spontaneous revertants of inositolless neurospora crassa.inositolless (inl-) neurospora crassa strains were treated with dna (allo-dna) of wild type n. crassa. hyphal fragments of a mycelial suspension of the n. crassa ragged inl- strain used as recipient in our transformation experiments were found to consist of units containing 100--1000 nuclei. in this strain the inositol-independent (inl+) nuclei appearing after dna treatment or by spontaneous reversion are present in the cytoplasm together with a large number of inl- nuclei. thus, both transforma ...1978161130
the 32 s rna of neurospora crassa mitochondria is not a precursor of the mitochondrial ribosomal rnas. 1979161331
mitochondrial ribosome assembly in neurospora crassa: mutants with defects in mitochondrial ribosome assembly. 1979161342
[plant extracts with cytostatic properties growing in cuba. i].the cytostatic activity of aqueous, alcoholic and ketonic extracts of 9 species of superior plants of the families fitolacaceae, compositae, moraceae, zingiberaceae, martiniaceae, mirtaceae, verbenaceae and annonaceae was assessed. the kubas microbiologic method and the fungus ascomiceto neurospora crassa were used in the assessment. the fungus growth was measured in millimeters. inhibition percentages for every case regarding control are reported. the best results were obtained from annona muri ...2009161407
isolation of 4 alpha-methyl-5 alpha-ergosta-8,24(28)-dien-3 beta-ol from ester fractions of nutritionally deprived neurospora crassa.a method of isolating pure fractions of 4 alpha-methyl-5 alpha-ergosta-8,24(28)-dien-38-ol for sterol intermediate studies is described. starvation cultures of neurospora crassa readily incorporate exogenous mevalonic acid into the sterol ester fraction. isolation involves a simple solvent extraction and two chromatograms. only the ester fraction yielded the required purity. radioactive 4 alpha-methyl-5 alpha-ergosta-8,24(28)-dien-3 beta-ol is readily produced from dl-[2-14c] mevalonic acid.1979161433
studies on copper toxicity in neurospora crassa. 2003161548
isolation and characterization of temperature-sensitive respiratory mutants of neurospora crassa.filtration-enrichment and inositol-less death methods of mutant isolation, coupled with a screen for cyanide-insensitive respiration, proved to be highly efficient methods for isolating temperature-sensitive (ts) nuclear neurospora mutants having defective respiration. eighteen different ts respiratory mutants have been isolated. most of them are pleiotropic and defective in one or more of the following phenotypes: cytochrome aa3, b, and c (individual or multiple defects); oligomycin inhibition ...1979161749
genetics of arginine biosynthesis in neurospora crassa.a large number of arginine-requiring mutants of neurospora was isolated, using a strain already partially impaired in an enzyme of the pathway. among the mutants, all previously described loci, except one, were represented, and several new loci were defined and mapped. four groups of mutants were of particular interest. first, the large group of arg-6 mutants, when tested for intragenic complementation, suggested a bifunctional gene, possibly controlling two steps in ornithine synthesis. this is ...1979161750
genetic control of phosphorus assimilation in neurospora crassa: dose-dependent dominance and recessiveness in constitutive mutants.mutants called nuc-1c, constitutive for alkaline phosphatase synthesis, were isolated and mapped very close to nuc-1 mutants in which this enzyme is not expressed. nuc-1 is epistatic to nuc-1c. nuc-1c acts only if it is cis to normal nuc-1 function. the preparation of partial diploids heterozygous for various nuc-1 alleles is described; nuc-1c is dominant to nuc-1+, which in turn is dominant to nuc-1. in heterocaryons with nuc-1+, nuc-1c is dominant when it is present in high proportion, but ess ...1979161751
comparative studies on the fermentative production of nucleotides by wild type neurospora crassa & an adenine auxotroph. 1979161763
metallothionein: an exceptional metal thiolate protein.metallothioneins are unusual, low molecular weight proteins of extremely high sulphur and metabl content. they occur in substantial quantity and in multiple variant forms in parenchymatous tissues (liver, kidney, intestines) of vertebrates and certain microorganisms (neurospora crassa, yeast). they are though to play a central role in the cellular metabolism of metals such as zinc, copper and cadmium. all mammalian forms studied are single chains with 20 cysteinyl residues among a total of 61 am ...1979162047
demonstration of myo-inositol-1-phosphate synthase and its assumed defective variant in various neurospora crassa strains by immunological methods.immunological experiments were performed to demonstrate myo-inositol-1-phosphate synthase (ec 5.5.1.4) and its assumed defective variant in various neurospora crassa stains. an enzymatically inactive protein fraction was isolated from the inl-mutant by the same procedure as that of the enzyme. it consisted of several components by gel electrophoresis, and produced a positive immune reaction demonstrated by immunodiffusion using immune sera produced against the enzyme. using immunodisc gel electr ...1979162120
genetic effects of pr toxin in eukaryotic microorganisms.the genetic activity of pr toxin, a mycotoxin from penicillium roqueforti, was studied in saccharomyces cerevisiae and neurospora crassa. the results show that pr toxin, without enzymic activation, causes gene conversion in s. cerevisiae strains d4 and d7, reverse mutation in s. cerevisiae strain d7 and n. crassa strain n24, and mitotic crossing-over in s. cerevisiae strain d7, in the log phase cells of s. cerevisiae the effects are more pronounced at alkaline than at acid ph. the active site re ...1979162284
hybridization of dna's from neurospora crassa strains may indicate base sequence alterations as a consequence of genetic transformation.deoxyribonucleic acids of neurospora crassa strains involved in genetic transformation experiments were studied by means of dna-dna hybridization. no significant difference was detected in the extent of hybridization reassociating 32p-dna of an inositol-requiring recipient strain with an excess amount of unlabelled homologous dna and that of the transformed, spontaneous revertant and wild-type strains. studies on the thermal stability of hybrids revealed 1.2-1.7% heterology between the recipient ...2003162331
zeaxanthin ([3r,3'r]-beta, beta-carotene-3-3'diol) as a resonance raman and visible absorption probe of membrane structure.when zeaxanthin ([3r,3r']-beta, beta-carotene-3,3'diol) is inserted into phospholipid dispersions and the latter heated through their gel-liquid crystal phase transitions, large changes are noted in the resonance raman and absorption spectra of the carotenoid molecule. by analogy with the data of carey and co-workers (j. raman spectrosc. 6:282) who studied the aggregation of zeaxanthin in acetone-water solutions, it is suggested that the carotenoid aggregates in the phospholipid gel state while ...1979162448
amino-acid sequence of copper-metallothionein from neurospora crassa. 1979162453
isolation and characterization of nuclei from neurospora crassa.a procedure was developed for isolating nuclei from either the conidial or germinated conidial growth phase of neurospora crassa. a frozen conidial suspension was lysed by passage through a french pressure cell, and the nuclei were freed from the broken cells by repeated homogenization in an omni-mixer. pure nuclei were obtained from the crude nuclear fraction by density banding in a ludox gradient. the final nuclear yield was 20 to 30%. the nuclei had a deoxyribonucleic acid (dna):ribonucleic a ...1995162536
circadian rhythms in neurospora crassa: oscillation in the level of an adenine nucleotide.in a mutant strain (bd) of neurospora, the biological clock is visibly expressed at the growing front of a mycelial mat by sequential periods of conidiating (spore-forming) and non-conidiating growth. the edges (8 mm) of the mycelium at different ages were sampled during a 31 h period, and the adenine nucleotide levels were enzymatically assayed. in the edge region, the total adenosine 5'-monophosphate (amp) level showed an oscillation, with a minimum of 0.5 mumol/g (residual dry weight) and a m ...1975163225
enzymes of deoxythymidine triphosphate biosynthesis in neurospora crassa mitochondria.intact mitochondria of neurospora crassa incorporate deoxythymidine 5'-monophosphate (dtmp) into deoxyribonucleic acid but not the label from (methyl-3h) deoxythymidine. mitochondrial homogenates contain deoxythymidylate kinase (ec 2.7.4.9), deoxycytidylate aminohydrolase (dcmp deaminase) (ec 3.5.4.12), and thymidylate synthetase (ec 2.1.1b), but not thymidine kinase (ec 2.7.1.21) activity. dtmp kinase is loosely bound to the mitochondrial membrane and is solubilized by 0.4 m kcl in mitochondria ...1996163227
azaguanine-resistant mutants induced by several mutagens in a neurospora heterokaryon.this paper reports the development of a new system for the detection of forward mutations in a heterokaryon of neurospora crassa. this system, designed to detect a wide variety of genetic alterations, is based upon the detection of 8-azaguanine-resistant mutants in an adenine-requiring heterokaryon carrying the aza-3 gene. induction of mutations in the aza-3 gene was detected after treatment of conidia with ultraviolet light, x-rays, ethyl methanesulfonate (ems), or the acridine mustard, icr-170 ...1975163959
adenosine 3',5'-cyclic monophosphate and morphology in neurospora crassa: drug-induced alterations.grown in liquid culture in the presence of a variety of structurally unrelated drugs, mycelia of wild-type neurospora assume a colonial or semicolonial growth habit similar to that of known morphological mutants. drugs that produce these morphological changes include atropine, theophylline, histamine, and several of the quinoline-containing antimalarials. each of these drugs decrease the endogenous adenosine 3',5'-cyclic monophosphate (camp) concentration of mycelia as a result of their effect o ...2003165170
mutants of neurospora deficient in nicotinamide adenine dinucleotide (phosphate) glycohydrolase.a new screening technique has been developed for the rapid identification of neurospora crassa mutants that are deficient in nicotinamide adenine dinucleotide glycohydrolase (nadase) and nicotinamide adenine dinucleotide phosphate glycohydrolase (nadpase) activities. using this procedure, five single-gene mutants were isolated whose singular difference from wild type appeared to be the absence of nad(p)ase (ec 3.2.2.6). all five mutants were found to be genetically allelic and did not complement ...1975165174
adenylate cyclase activity in neurospora crassa. 2003165692
differential rates of synthesis of glycerokinase and glycerophosphate dehydrogenase in neurospora crassa during induction. 1975165778
organization and control in the arginine biosynthetic pathway of neurospora.eight enzymes involved in the conversion of acetylglutamate to arginine in neurospora crassa were studied. the data indicate that of three enzymes early in the sequence, only the first, acetylglutamate kinase, is a nonorganellar enzyme. the next two, n-acetyl-gamma-glutamyl-phosphate reductase and acetylornithine aminotransferase, are in the mitochondrion, which was previously shown to contain the subsequent enzymes: acetylornithine-glutamate acetyltransferase, ornithine carbamyltransferase, and ...2003166979
the regulated catabolism of endogenous and exogenous phosphatidylinositol by saccharomyces cerevisiae leading to extracellular glycerophosphorylinositol and inositol.it was previously shown that phosphatidylinositol catabolism leads to the accumulation of glycerophosphorylinositol in the culture medium of saccharomyces cerevisiae. we now find that lack of an energy source (glucose) reduces the formation of glycerophosphorylinositol and increases extra-cellular inositol. this situation is reversed by refeeding glucose. [3h]phosphatidylinositol is the precursor of extra-cellular [3h]inositol with energy-starved cells. extracellular glycerophosphorylcholine and ...1975166987
regulation of mitochondrial membrane assembly in neurospora crassa. transient expression of a respiratory mutant phenotype.cultures of mutant cni-1, a chromosomal mutant of neurospora crassa, undergo a marked change in respiratory properties as the age of the culture increases. early log phase cultures have a high level of respiration that is insensitive to inhibition by cyanide or antimycin a. late log and stationary phase cultures have reduced rates of respiration. a high percentage of this respiration is inhibited by cyanide. mitochondria from early log phase cni-1 have an excess of cytochrome c and little or no ...1975168205
oxidation processes and ubiquinone localization in the branched respiratory system of mi-1 mutant of neurospora crassa.1. stimulation of succinate oxidation in mi-1 mitochondria by mg2+ and pi is abolished on uncoupling, which points to the energy-linked activation of succinate oxidation. 2. mitochondria exhibited respiratory control with succinate and nadh when the cyanide-insensitive oxidation was inhibited by salicylhydroxamic acid (sham). sham lowered the oxidation rate with nadh and succinate to the same level, though the nadh oxidation rate was 2.5 times as high as with succinate. 3. despite the high stimu ...1997168706
kinetics and morphology of glucose-limited cultures of moulds grown in a chemostat and on solid media.the affinity (ks value) of geotrichum candidum for glucose determined from chemostate cultures was ca. 1 mg/1. ks values for glucose was also estimated from the radial growth rates of colonies of g. candidum and neurospora crassa grown on media solidified with agar or silica gel. an assessment is made of the use of colony radial growth rate to determine substrate affinities. the length of apical and intercalary hyphal comparte ments, internode length and the diameter of leading hyphaat the margi ...1975168829
two forms of a mitochondrial endonuclease in neurospora crassa.mitochondrial nuclease activity in neurospora crassa occurs in membrane-bound and soluble forms in approximately equal proportions. these activities apparently are due to the same enzyme, which has an approximate molecular weight of 120 000. a portion of the insoluble enzyme appears to be associated with the inner mitochondrial membrane and is resistant to solubilization by detergent treatment as well as by physical disruption methods.1975168950
change of the cytochrome oxidase level during exponential growth in neurospora crassa.in neurospora cells growing in various media, the specific activity of cytochrome oxidase increases very markedly during early exponential growth, reaching a maximum after 4-5 duplication times, then it slowly declines.2003169142
the influence of amino acid substitutions on the conformational energy of cytochrome c.conformational energies have been evaluated for each of the staggered side-chain conformations associated with the 261 amino acid substitutions known to occur among 60 eucaryotic species. at least 86% of these substitutions can be sterically accommodated (one at a time) within the structure of horse-heart cytochrome c resulting from conformational energy refinement. simultaneous incorporation of all pertinent amino acid substitutions found in eight representative species into the refined horse-h ...1975169879
neurospora crassa conidial germination: role of endogenous amino acid pools.the levels of the endogenous amino acid pools in conidia, germinating conidia, and mycelia of wild-type neurospora crassa were measured. three different chromatographic procedures employing the amino acid analyzer were used to identify and quantitatively measure 28 different ninhydrin-positive compounds. all of the common amino acids were detected in conidial extracts except proline, methionine, and cystine. the levels of these three amino acid pools were also very low in mycelia. during the fir ...1975170245
the pyridine nucleosidases from bacillus subtilis and neurospora crassa. isolation and structural properties. 1975170869
[studies on the conidial differentiation of "neurospora crassa" vi.--functional anomalies of the conditional aconidial mutant "amycelial" (author's transl)].studies using the morphological mutant "amycelial"--a conditional, aconidial strain of n. crassa--have revealed certain consistent functional and biochemical differences from wild type strains showing normal morphology and conidia formation. thus it was found that the mutant strain showed an abnormal utilization of protein reserves at a time when there is extensive degradation during conidiogenesis in wild type. in addition, the mutant exhibited abnormally low oxygen consumption and free amino a ...1975173223
partial amino-acid sequence of nad-specific glutamate dehydrogenase of neurospora crassa.parts of the primary structure of the nad-specific glutamate dehydrogenase [l-glutamate:nad oxidoreductase (deaminating), ec 1.4.1.2] from neurospora crassa are presented. segments of the sequence representing 886 unique amino-acid residues have been determined; the largest contains 267 residues. there are only short regions of possible homology between this enzyme and the glutamate dehydrogenases of bovine liver or the nadp-specific enzyme of neurospora. the large size of the subunit (116,000 m ...1975174080
influence of the carbon source on glycerol kinase activity in neurospora crassa.the level of glycerol kinase activity in neurospora crassa was shown to change in response to resuspension of sucrose-grown mycelia in fresh medium containing a new carbon source: the magnitude of the change depended on the new carbon source provided. certain carbon sources, such as glucose and fructose, inhibited the small increase that occurred in the absence of any carbon source. others, and in particular deoxyribose, galactose, glycerol and ribose, greatly enhanced this increase. the activit ...1987174743
control of neurospora crassa morphology by cyclic adenosine 3', 5'-monophosphate and dibutyryl cyclic adenosine 3', 5'-monophosphate.the role of cyclic adenosine 3', 5'-monophosphate (cyclic amp) in the control of the neurospora asexual life cycle was studied. endogenous cyclic amp levels were 10 to 20 times higher in strains having the wild-type cr-1 allele than in those carrying the mutated allele. in a wild-type strain these levels remained constant throughtout the entire growth period in shaken liquid cultures, except during a short period at the beginning of the stationary growth phase. in this period a marked increase i ...1995177398
genetic and enzymatic analysis of a glycerol kinase deficient mutant in neurospora crassa.genetic analysis showed that the glycerol non-utilizing isolate gly-u(234) of neurospora crassa is derived by mutation in a nuclear gene situated in the right arm of linkage group i, about 2.2 cross-over units distal to ad-9 and 11 units proximal to nit-1. enzymatic testings using a radiochemical method indicate that the mutant is deficient for the enzyme glycerol kinase. the radiochemical testings further indicate that the mutation has inactivated an inducible glycerol kinase, while a low resid ...1996177854
studies on the poky mutant of eurospora crassa. fingerprint analysis of mitochondrial ribosomal rna.base sequence and methylation of mitochondrial ribosomal rnas from wild type and poky strains of neurospora crassa were compared to determine whether a mutational lesion exists in poky 19 s rna. at the outset, new procedures were developed for the isolation of intact nucleic acids from neurospora mitochondria based on the substitution of ca2+ for mg2+ in the isolation media to inhibit mitochondrial nuclease activity. using these procedures, intact and highly purified 32p-labeled ribosomal rnas w ...1997178661
carbon-13 nuclear-magnetic-resonance spectroscopy of whole cells and of cytochrome c from neurospora crass grown with (s-me-13c)methionine.neurospora crassa cytochrome c biosynthetically labelled with [s-me-13c]methionine was prepared and analysed by 13c nuclear-magnetic-resonance spectroscopy. the methyl group of methionine is extensively incorporated into an n-trimethyl-lysine-72 residue arise from s-adenosylmethionine transmethylation, and that the methyl carbons of methionine residues are sufficiently close to the haem centre to experience chemical shifts from the ring currents of the tetrapyrrole pi electrons and broadening du ...1997179524
characterization of a seventh different subunit of beef heart cytochrome c oxidase. similarities between the beef heart enzyme and that from other species.beef heart cytochrome c oxidase has been resolved into seven subunits by electrophoresis in highly cross-linked gels containing urea and sodium dodecyl sulfate. the molecular weights of the polypeptides are estimated to be i, 35 400; ii, 24 100; iii, 21 000; iv, 16 800; v, 12 400; vi, 8200; and vii, 4400. it has been shown that subunits ii and iii can coelectrophorese on standard sodium dodecyl sulfate-polyacrylamide gels and appear as a single component with an apparent molecular weight of 22 5 ...1976181053
adenosine 3':5'-cyclic monophosphate deficiency in neurospora crassa.depending on growth conditions, the adenosine 3':5'-cyclic monophosphate (cyclic amp) levels of the fr mutant, a morphologically aberrant strain of neurospora crassa, are reduced 2- to 5-fold. by taking advantage of the differences in phenotype of fr in liquid and agar cultures and the positive response of fr grown on solid support to exogenous theophylline, a relationship between the degree of morphological abnormality and intracellular cyclic amp levels of the mutant is observed. progressive r ...1976184453
the effect of cyclic adenosine monophosphate on the growth of neurospora crassa. 1976185527
the function of mitochondrial genes in neurospora crassa.the 18 extranuclear mutants of neurospora crassa, without exception, have abnormal mitochondrial respiratory systems. on the basis of genetic, phenotypic and physiological criteria, these mutants are divided into four groups: 1) the cytochrome aa3 and b deficient "poky" variants that are defective in mitochondrial ribosomes assembly, 2) the cytochrome aa3 deficient mutants, [mi-3] and [exn-5], that appear to have genetic lesions affecting a component of a regulatory system controlling cytochrome ...1976187290
the location of the feedback-specific region with the pyrimidine-3 locus of neurospora crassa.the purimidine-3 locus of neurospora crassa specifies two enzyme activities, pyrimidine-specific carbamyl phosphate synthetase (cpspyr) and aspartate transcarbamylase (atc). atc is translationally distal. cpspyr, but not atc, is subject to feedback inhibition by uridine triphosphate (utp). to investigate the location of the feedback-specific region within the locus, inhibition of a number of pyr-3 alleles by utp was investigated. all cps+ atc- polar alleles, revertants of cps- atc- polar alleles ...1976187923
glutamine utilization in both the arginine-specific and pyrimidine-specific carbamoyl phosphate synthase enzymes of eurospora crassa.as glutamine-dependent carbamoyl phasphate synthetase (cps) activity in some organisms is composed of a glutaminase and an ammonium-dependent cps, cps- mutants in neurospora crassa were examined for glutamine- and ammonium-dependent cps activities. no evidence was found that the genetic location of these two functions were separable. this is discussed with reference to the close genetic proximity of the cpspyr and aspartate carbamoyltransferase (act) structural gene (pyr-3) and the arg-2 gene wh ...1976189179
induction of enzymes of the glycerophosphate pathway in leu-5 mutants of neurospora crassa.the inducible cytosolic glycerokinase and mitochondrial glycerol-3-phosphate dehydrogenase have been examined during the glycerol-specific induction in neurospora crassa. although both the fully induced levels and the respective rates of synthesis of these two enzymes were less than observed with wild-type cells, there were no major differences in the relative rates of induction of the glycerol-3-phosphate dehydrogenase at either permissive or restrictive temperatures. these results indicate tha ...1976189751
inhibition of aminoacyl-transfer ribonucleic acid synthetases and the regulation of amino acid biosynthetic enzymes in neurospora crassa.growth conditions that result in the accumulation of the tryptophan intermediate indoleglycerol phosphate or of the histidine intermediate imidazoleglycerol phosphate cause mycelia of neurospora crassa to exhibit an immediate and sustained increase in the differential rate at which the biosynthetic enzymes of the tryptophan, histidine, and arginine pathways are synthesized. these accumulated intermediates are shown to be inhibitors of the activity of aminoacyltransfer ribonucleic acid (trna) syn ...1977191433
control of the production of orthophosphate repressible extracellular enzymes in neurospora crassa.the abilities of purine- and pyrimidine-requiring mutants to produce six orthophosphate repressible extracellular enzymes, alkaline phosphatase, 5'-nucleotidase, acid phosphatase, two nucleases and ribonuclease n1 were examined by culturing these mutants in low and high phosphate media containing nucleotide or nucleoside. all the purine requiring mutants produced significantly reduced amounts of alkaline phosphatase, 5'-nucleotidase, acid phosphatase, alkaline nuclease and acid nuclease ranging ...1977194139
the role of carbohydrate in the glycoenzyme invertase of neurospora crassa.data obtained concerning the carbohydrate moieties of the glycoenzyme invertase (ec 3.2.1.26, beta-d-fructofuranoside fructohydrolase) from neurospora crassa were consistent with a linkage of some carbohydrate chains by o-glycosidic bonds to serine and threonine residues; the possibility of n-glycosylamine linkage of some of the carbohydrate to the amide group of asparagine is also indicated. the invertase was remarkably stable on storage at low temperatures. oxidation of the carbohydrate residu ...1992195681
cytochrome c-specific protein methylase iii from neurospora crassa.a protein methylase iii responsible for specifically methylating the cytochrome c in neurospora crassa was partially characterized by using unmethylated horse heart cytochrome c as a substrate. this enzyme utilizes s-adenosyl-l-methionine as the methyl donor. an analysis of the distribution of [14c]methyl groups in the peptides obtained by chymotrypsin digestion of the enzymically methylated cytochrome c showed that all of the radioactivity could be recovered within a single peak after chromatog ...1977196592
[effect of liver chromatin dnase on closed circular dna of pm-2 phage and simian virus 40].comparative effect of the dnase from rat liver chromatin and neurospora crassa endonuclease s1 on closed circular superhelical dna of pm-2 phage and simian virus 40 is studied. it is shown that both of them--the dnase from chromatin proteins and endonuclease s1--are specific to single-stranded regions in dna molecular. it is suggested that chromatin protein dnase participates in reparation processes.1977196682
the effect of phosphatidylcholine depletion on biochemical and physical properties of a neurospora crassa membrane mutant.by using the choline starvation process it is possible to deplete the membranes of neurospora crassa choline auxotroph chol-1 of phosphatidylcholine, without affecting the viability of germinated spores or whole mycelium. spin label probes were used to examine the possible dependence of the physical state of cellular lipids on the presence of phosphatidylcholine in the membranes. increased freedom of rotational motion of lipid soluble probes was regularly detected in choline-starved mycelium. th ...1977197995
cyclic amp and the plasma membrane potential in neurospora crassa.diverse treatments, which have been shown by slayman, c. l. (1977) in water relations in membrane transport in plants and animals (jungreis, a., hodges, t. k., kleinzeller, a., and schultz, s. g., eds) pp. 69-86, academic press, new york, to depolarize the plasma membrane of neurospora, increase levels of adenosine 3':5'-monophosphate (cyclic amp) in the organism. the treatments include those producing large transport fluxes of metabolizable or nonmetabolizable compounds, rapid temperature drops ...1977198403
preparation of polypeptide subunits of cytochrome oxidase from neurospora crassa.cytochrome oxidase was purified from neurospora crassa by ammonium sulfate fractionation in the presence of bile salts. the enzyme preparations contained 10-13 nmol of heme a per mg of protein; no other hemoproteins could be detected. dodecylsulfate gel electrophoresis resolved the enzyme complex into seven major bands, representing seven polypeptide subunits. a procedure is described that allows the isolation of these enzyme subunits on a large scale starting from a single batch of oxidase prep ...1977199436
nicotinamide adenine dinucleotide-specific glutamate dehydrogenase of neurospora. vi. isolation and sequences of eighteen fragments from the cyanogen bromide digest.the 1030-residue polypeptide chain of the nad-specific glutamate dehydrogenase of neurospora crassa was fragmented by treatment with cyanogen bromide. the isolation and sequences of 18 fragments ranging in size from 4 to 51 residues are described. some of these peptides proved to be cleavage products resulting from hydrolysis at acid-sensitive aspartyl-prolyl bonds. some overlaps could be deduced on the basis of known sequences of peptides obtained by tryptic hydrolysis.1977199601
nicotinamide adenine dinucleotide-specific glutamate dehydrogenase of neurospora. vii. isolation and sequences of three large cyanogen bromide peptides.the isolation and sequences of three peptides of large size from a cyanogen bromide digest of the nad-specific glutamate dehydrogenase of neurospora crassa are reported. these three peptides comprise 86, 117, and 134 residues, respectively, and represent approximately 30% of the estimated 1030 residues in the peptide chain.1977199602
nicotinamide adenine dinucleotide-specific glutamate dehydrogenase of neurospora. viii. isolation and sequences of peptides from a tryptic hydrolysate of the maleylated protein.the nad-specific glutamate dehydrogenase of neurospora crassa was s-carboxymethylated with [14c]iodoacetate, maleylated, and hydrolyzed with trypsin. the isolation and sequences of the resulting peptides are described. these peptides gave information on the structure of the protein that was previously unknown and gave many overlaps of previously isolated segments of the protein.1977199603
nicotinamide adenine dinucleotide-specific glutamate dehydrogenase of neurospora crassa. ix. isolation and sequences of several large cyanogen bromide peptides.the isolation and sequences of several large peptides from cyanogen bromide cleavage of the 1030-residue polypeptide chain of the nad-specific glutamate dehydrogenase of neurospora crassa are described. one of these is in the 669-residue sequence of the cooh-terminal end of the protein. the remaining peptides have been aligned in two partial sequences in the nh2-terminal portion of the polypeptide chain.1977199604
kinetic studies on the transport of cytoplasmically synthesized proteins into the mitochondria in intact cells of neurospora crassa.the transport of cytoplasmically synthesized mitochondrial proteins was investigated in whole cells of neurospora crassa, using dual labelling and immunological techniques. in pulse and pulse-chase labelling experiments the mitochondrial proteins accumulate label. the appearance of label in mitochondrial protein shows a lag relative to total cellular protein, ribosomal, microsomal and cytosolic proteins. the delayed appearance of label was also found in immunoprecipitated mitochondrial matrix pr ...1977202461
cytochrome c-specific protein-lysine methyltransferase from neurospora crassa. purification, characterization, and substrate requirements. 1978203592
ageing of neurospora crassa. v. lipid peroxidation and decay of respiratory enzymes in an inositol auxotroph. 1993204836
ageing of neurospora crassa. vi. cytochemical and cytological correlates of senescence in three model systems. 1993204837
electron transport in the cni-1 mutant of neurospora crassa.1. mitochondria from the nuclear mutant cni-1 have no optically detectable cytochrome aa3 in early log phase growth. these mitochondria have a high level of respiration that is not inhibited by cyanide but is inhibited by salicylhydroxamic acid. they also show a substantial amount of cyanide-sensitive respiration. 2. as cultures of mutant cni-1 age, flux through the hydroxamate-sensitive pathway decreases markedly while flux through the cytochrome chain remains constant. 3. growth studies with m ...1992206437
the state of copper in neurospora laccase.1. neurospora crassa laccase has been prepared from the growth medium and studied by optical absorption, circular dichroism and electron paramagnetic resonance (epr) spectroscopy. the molecular weight, the copper content and the amino acid composition have also been determined. 2. the molecular weight as determined by gel filtration in 6 m guanidine hydrochloride and by sodium dodecyl sulfate gel electrophoresis is found to be 64 000. the enzyme contains 3.8 copper ions per 64 000. 3. the visibl ...1992207349
structural analysis of viral replicative intermediates isolated from adenovirus type 2-infected hela cell nuclei.deoxyribonucleoprotein complexes released 17 h postinfection from adenovirus type 1 (ad2)-infected hela cell nuclei were shown by electron microscopy to contain filaments much thicker (about 200 a [20 nm]) than double-stranded dna (about 20 a [2 nm]). the complexes were partially purified through a linear sucrose gradient, concentrated, and further purified in a metrizamide gradient. the major protein present in the complexes was identified as the 72,000-dalton (72k), adenovirus-coded single-str ...1978207893
disappearance of the cyanide-insensitive pathway of oxidation in mitochondria of mi-1 mutant of neurospora crassa in vitro.oxidation of exogenous nadh in mitochondria isolated from wild type and mi-1 mutant of neurospora crassa decreases rapidly in vitro. in mi-1 mutant mitochondria the inactivation concerns the alternate pathway of oxidation whereas in the wild type it involves an unknown component of the respiratory chain. the activity of the primary nadh dehydrogenase is constant within the time of the experiments (2-4 h). nadh oxidase is not inactivated if oxygen is removed from the incubation medium by nitrogen ...1978208334
a possible model for the structure of the neurospora carbamoyl phosphate synthase-aspartate carbamoyl transferase complex enzyme.the pyrimidine-3 locus of neurospora crassa specifies a multienzyme complex comprising pyrimidine-specific carbamoyl phosphate synthase (cpspyr) and aspartate carbamoyl transferase (act). it appears to be divided into a translationally proximal cps-specific region and a distal act-specific region. levels of complementation for act activity between pairs of four pyr-3 cps+ act- mutants showed a range from 12% to 68% of the wild-type level of the enzyme. this is interpreted as interallelic complem ...1978209307
a nuclear mutant of neurospora crassa lacking subunit 1 of cytochrome c oxidase. 1989210181
effect of carbon source on enzymes involved in glycerol metabolism in neurospora crassa.specific activities of eight enzymes involved in glycerol metabolism were determined in crude extracts of three strains of neurospora crassa after growth on six different carbon sources. one of the strains was wild type, which grew poorly on glycerol as sole carbon source; the other two were mutant strains which were efficient glycerol utilizers. a possible basis for this greater efficiency of glycerol utilization was catabolite repression of glyceraldehyde kinase by glycerol in wild type, and t ...1987211971
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