Publications
| Title | Abstract | Year(sorted ascending) Filter | PMID Filter |
|---|
| the effects of spore loading on the growth of penicillium chrysogenum immobilised in kappa-carrageenan. | penicillium chrysogenum spores were immobilised in kappa-carrageenan. the effect of the number of viable spores immobilised per bead on the rate of germination and degree of subsequent mycelial growth was investigated. the distribution of active mycelium throughout the bead was determined. at a high spore loading (10(3)-10(4) viable spores per bead) the biomass concentration was low and the majority of the actively respiring biomass was located at the bead periphery. reducing the spore loading ( ... | 1991 | 1367643 |
| molecular characterization and functional analysis in aspergillus nidulans of the 5'-region of the penicillium chrysogenum isopenicillin n synthetase gene. | the isopenicillin n synthetase gene (pcbc) was isolated from a genomic library of penicillium chrysogenum bc39813, a penicillin production strain. the nucleotide sequence, including 555 bp upstream of the translation start site was determined. various deletions within the pcbc 5'-region were constructed and linked to the escherichia coli lacz gene. an aspergillus nidulans argb strain was transformed with dna of these constructions. the region essential for promoter function could be localized be ... | 1991 | 1367495 |
| strain improvement of penicillium chrysogenum by recombinant dna techniques. | the pende gene from penicillium chrysogenum has been isolated; the gene is located in close vicinity of the pcbc gene. amplification of the pcbc-pende gene cluster in penicillium chrysogenum wis54-1255 leads to a significant increase in penicillin production. in selected transformants an increase of up to 40% is observed. | 1991 | 1367496 |
| decreased production of para-hydroxypenicillin v in penicillin v fermentations. | penicillin v (phenoxymethyl penicillin) is produced by industrial strains of penicillium chrysogenum in the presence of phenoxyacetic acid (poac), a side-chain precursor for the penicillin v molecule. the wild-type strain of p. chrysogenum produces an undesirable penicillin byproduct, para-hydroxypenicillin v (p-oh penicillin v), in addition to penicillin v, via para-hydroxylation of poac and subsequent incorporation of the p-oh phenoxyacetic acid into the penicillin molecule. most of the p-oh p ... | 1991 | 1367508 |
| primary structure of protein moiety of penicillium notatum phospholipase b deduced from the cdna. | phospholipase b has not yet been well defined. the most important points about this enzyme are its relationships with lysophospholipase and phospholipase a1. as reported [saito, k., sugatani, j. & okumura, t. (1991) methods enzymol. 197, 446-456], penicillium notatum phospholipase b is a glycoprotein with a molecular mass of 95 kda and intrinsic lysophospholipase and phospholipase b activities; however, by endogenous proteolytic modification, its phospholipase b activity is lost almost completel ... | 1991 | 1722456 |
| characterization of the cephalosporium acremonium pcbab gene encoding alpha-aminoadipyl-cysteinyl-valine synthetase, a large multidomain peptide synthetase: linkage to the pcbc gene as a cluster of early cephalosporin biosynthetic genes and evidence of multiple functional domains. | a 24-kb region of cephalosporium acremonium c10 dna was cloned by hybridization with the pcbab and pcbc genes of penicillium chrysogenum. a 3.2-kb bamhi fragment of this region complemented the mutation in the structural pcbc gene of the c. acremonium n2 mutant, resulting in cephalosporin production. a functional alpha-aminoadipyl-cysteinyl-valine (acv) synthetase was encoded by a 15.6-kb ecori-bamhi dna fragment, as shown by complementation of an acv synthetase-deficient mutant of p. chrysogenu ... | 1991 | 1706706 |
| analysis of a high frequency transformation system for ophiostoma ulmi, the causal agent of dutch elm disease. | a transformation system for ophiostoma ulmi (buism.) nannf. was developed and analyzed. protoplasts were generated from actively budding yeastlike cells by digestion with novozym 234 in mgso4 after pretreatment with 2-mercaptoethanol. protoplast regeneration was most efficient when 0.6 m sucrose was used as the osmoticum. several plasmids containing fusions between fungal promoters and a bacterial gene for hygromycin phosphotransferase successfully transformed o. ulmi to hygromycin resistance. o ... | 1991 | 2000087 |
| phospholipase b from penicillium notatum. | 1991 | 1646934 | |
| growth and the production of penicillins in penicillium chrysogenum with palm oil and its various fractions as carbon sources. | the utilisation of palm oil and its fractions by penicillium chrysogenum for growth and penicillin production is strain-dependent. strain h1107 could utilise crude palm oil, its liquid (palm olein) and solid (palm stearin) fractions and its component fatty acids (oleic, palmitic, stearic and myristic) as the main carbon source; strain m223 could not. cell-bound lipase activity was higher in h1107 than in m223. | 1991 | 1368105 |
| a model for penicillin production with and without temperature shift after the growth phase. | a strain of penicillium chrysogenum producing about 8 milligrams/l of penicillin v, was cultivated in a 10-1 bioreactor. under carbon (c)-limitation during the production phase a glucose/ammonium sulphate mixture was fed using microprocessor control. when the temperature was shifted from 25 degrees c to 30 degrees c at the end of the active growth phase, the specific penicillin production rate was increased by 30%, while the yield remained constant. maximal productivity without sporulation was o ... | 1992 | 1368200 |
| genetic instability of industrial strains of penicillium chrysogenum. | it has shown that several characteristics of high-producing industrial strains of penicillium chrysogenum tend to segregate in the course of cultivation (slant-to-slant transfer). segregation includes a decrease in the yield of penicillin, mean conidial size, mean size of the nuclei, and an increase in the proportion of morphologically wild-type colonies. these lower-producing segregants also have a higher sensitivity against ultraviolet radiation and, as shown by cytofluorometric methods, a low ... | 1992 | 1368203 |
| the influence of preculture on the process performance of penicillin v production in a 100-l air-lift tower loop reactor. | the influence of stirrer speed in the third preculture on the performance of penicillin v production by penicillium chrysogenum in complex medium in a 100-l air-lift tower loop reactor was investigated. the process performance in the main culture was improved by increasing the stirrer speed from 500 to 750 rpm: the pellet size was reduced to half, the cell growth was influenced only slightly, but the production phase was extended considerably, and the final penicillin concentration was increased ... | 1992 | 1368239 |
| transcript analysis of penicillin genes from penicillium chrysogenum. | the presence of a transcriptional control simultaneously affecting the expression of the three penicillin biosynthetic genes, pcbab, pcbc, and pende (pen genes), was demonstrated in penicillium chrysogenum. using probes specific to each gene, it was observed that the highest level of expression of the pen genes occurred during exponential growth, in both the original ancestral strain (nrrl1951) and a high-penicillin producing strain p2. expression also occurred in the presence of high concentrat ... | 1992 | 1735125 |
| clusters of genes for the biosynthesis of antibiotics: regulatory genes and overproduction of pharmaceuticals. | in the last decade numerous genes involved in the biosynthesis of antibiotics, pigments, herbicides and other secondary metabolites have been cloned. the genes involved in the biosynthesis of penicillin, cephalosporin and cephamycins are organized in clusters as occurs also with the biosynthetic genes of other antibiotics and secondary metabolites (see review by martín and liras [65]). we have cloned genes involved in the biosynthesis of beta-lactam antibiotics from five different beta-lactam pr ... | 1992 | 1368054 |
| genomic dna sequences of mitochondrial trna genes in fungi penicillium chrysogenum kctc1262: trna(arg), trna(asn) and trna(tyr) genes. | 1992 | 1280811 | |
| evaluation of two unstructured mathematical models for the penicillin g fed-batch fermentation. | the mathematical model for the penicillin g fed-batch fermentation proposed by heijnen et al. (1979) is compared with the model of bajpai & reuss (1980). although the general structure of these models is similar, the difference in metabolic assumptions and specific growth and production kinetics results in a completely different behaviour towards product optimization. a detailed analysis of both models reveals some physical and biochemical shortcomings. it is shown that it is impossible to make ... | 1992 | 1285644 |
| fatal necrotizing esophagitis due to penicillium chrysogenum in a patient with acquired immunodeficiency syndrome. | although blue-green molds of the genus penicillium are ubiquitous in the human environment, invasive penicilliosis is uncommon and primarily encountered among immunosuppressed patients. a patient with hiv infection who died of severe necrotizing esophagitis caused by penicillium chrysogenum is reported and the relevant english language literature on human penicilliosis is reviewed. although infectious esophagitis is commonly associated with aids, penicillium esophagitis has not been described in ... | 1992 | 1291312 |
| [selection of penicillium chrysogenum--producer of penicillin with several valuable technologic features]. | the efficiency of the routine methods for improvement of p. chrysogenum providing specific selection by several features with testing one of them was studied. a new highly potent strain of p. chrysogenum producing phenoxymethylpenicillin was isolated. the strain is characterized by a shorter fermentation cycle, lower viscosity of the fermentation broth and capacity for synthesizing 32,600 units/ml of phenoxymethylpenicillin under industrial conditions (in a lactose medium) by the 97th hour of th ... | 1992 | 1304123 |
| saprophytic and keratinophilic fungi isolated from desert and cultivated soils continuously exposed to cement dust particles in egypt. | forty soil samples collected from desert (uncultivated) and cultivated soils, exposed continuously to cement dust were screened for their content of saprophytic and keratinophilic fungi using the hair baiting technique and the dilution plate method. using the hair baiting technique, 21 genera and 31 species were collected from 20 samples of each of desert (15 genera and 21 species) and cultivated (17 genera and 24 species) soils, on sabouraud's dextrose agar. these included chrysosporium keratin ... | 1992 | 1325092 |
| [effect of penicillin precursors on antibiotic biosynthesis in various strains]. | the regularities of biosynthesis of 6-aminopenicillanic acid (6-apa), benzylpenicillin (bp) and phenoxymethylpenicillin (pmp) by the strains under the investigation did not significantly differ. in the absence of the precursor both the strains mainly synthesized 6-apa. phenylacetic acid (paa) and phenoxyacetic acid (poaa) provided directed biosynthesis: the fungus synthesized bp or pmp depending on the precursor nature. when the amount of the precursors was not sufficient, 6-apa was synthesized ... | 1992 | 1326929 |
| use of long-chain fatty acid-coa ligase (amp-forming) from pseudomonas fragi for the 'in vitro' synthesis of natural penicillins. | five different naturally occurring penicillins containing as side chains hexanoic, trans-3-hexenoic, heptanoic, octanoic or trans-3-octenoic acids have been synthesized 'in vitro' by coupling long-chain fatty acid-coa ligase (amp-forming) (ec 6.2.1.3) from pseudomonas fragi (lfcoa-l) with acyl-coa: 6-aminopenicillanic acid acyltransferase (at) from penicillium chrysogenum. the quantity of penicillin produced was directly related with the carbon length of the side chain precursor tested, being ma ... | 1992 | 1327953 |
| isolation and characterization of the acetyl-coa synthetase from penicillium chrysogenum. involvement of this enzyme in the biosynthesis of penicillins. | acetyl-coa synthetase (acs) of penicillium chrysogenum was purified to homogeneity (745-fold) from fungal cultures grown in a chemically defined medium containing acetate as the main carbon source. the enzyme showed maximal rate of catalysis when incubated in 50 mm hcl-tris buffer, ph 8.0, at 37 degrees c. under these conditions, acs showed hyperbolic behavior against acetate, coa, and atp; the km values calculated for these substrates were 6.8, 0.18, and 17 mm, respectively. acs recognized as s ... | 1992 | 1347531 |
| isolation of deacetoxycephalosporin c from fermentation broths of penicillium chrysogenum transformants: construction of a new fungal biosynthetic pathway. | deacetoxycephalosporin c (daoc), a precursor of cephalosporins excreted by cephalosporium and streptomyces species, has been produced in penicillium chrysogenum transformed with dna containing a hybrid penicillin n expandase gene (cefeh) and a hybrid isopenicillin n epimerase gene (cefdh). daoc from a p. chrysogenum transformant was identified by ultraviolet light (uv), high performance liquid chromatography (hplc), nuclear magnetic resonance (nmr) and mass spectrum analyses. p. chrysogenum tran ... | 1992 | 1354366 |
| influence of medium composition on penicillin v production in a stirred tank reactor. | penicillin production with a high-producing strain penicillium chrysogenum was investigated under well-controlled conditions in a stirred tank reactor with complex media containing lard oil and lactose on the one hand, and lactose on the other hand. with lard oil, cell growth and product formation rates were higher, and the production time was shorter by 40 h than without lard oil. on account of the longer production time without lard oil, the amount of beta-lactam compounds was higher (29.93 g ... | 1992 | 1368803 |
| determination of the rate-limiting step(s) in the biosynthetic pathways leading to penicillin and cephalosporin. | this paper is a review of strategies that have been used, or that could be used, to determine the rate-limiting step(s) in the biosynthetic pathways leading to penicillin or cephalosporin. information is summarized from published material that involves studies with low-producing strains of penicillium chrysogenum and cephalosporium acremonium. we also summarize information derived from some high-producing production strains. identification of the rate-limiting step(s) was of great interest to us ... | 1992 | 1368868 |
| mitotic instability of integrated plasmids in penicillium chrysogenum transformants. | transformation vectors based on the streptoalloteichus hindustanus phleomycin-resistance gene placed under the control of either the penicillium chrysogenum trpc or pcbc promoters were constructed (plasmids pgs1 and pgs7 respectively). up to 100 transformants per microgram of dna were obtained with pgs7 in p. chrysogenum strain p2. in order to follow the expression of additional penicillin biosynthetic genes introduced by transformation, a pcbc::lacz gene fusion was introduced into pgs1, generat ... | 1992 | 1368897 |
| oxygen utilisation by isopenicillin n synthase from penicillium chrysogenum. | the enzyme isopenicillin n synthase (ipns) converts delta-(l-alpha- aminoadipyl)-l-cysteinyl-d-valine (acv) to isopenicillin n; an equimolar amount of oxygen is used in this oxidative ring closure reaction. oxygen uptake rates of the reaction catalysed by partially purified ipns from penicillium chrysogenum sc 6140 and p2 were measured using an oxygen electrode. in contrast to published properties of cephalosporium acremonium ipns, the enzyme from p. chrysogenum was not stimulated by the additio ... | 1992 | 1369045 |
| an integrated process for the production and biotransformation of penicillin. | the extraction of penicillin g (pg) from the filtered cultivation medium of penicillium chrysogenum and its conversion into 6-amino penicillanic acid (6-apa) and phenyl acetic acid (pha) at ph 8 was performed in a 10 l kühni extractor during the production by means of penicillin-g-amidase immobilized in a liquid membrane carrier system (lm). 6-apa was enriched in lm, and the pha returned to the cultivation medium. after electrocoalescence of lm, the 6-apa was converted into ampicillin with the s ... | 1992 | 1369419 |
| characterization of a monoclonal antibody (p40) against the 68 kd major allergen of penicillium notatum. | a monoclonal antibody (moab p40) against the 68 kd major allergen of penicillium notatum (p. notatum) was obtained by immunizing the mouse with a crude extract of p. notatum. analysed by two-dimensional gel electrophoresis and immunoblotting, p40 reacted with two different isoforms of the 68 kd component of p. notatum with pis of 5.4 and 5.5. in addition to p. notatum, p40 showed positive elisa activity to aspergillus fumigatus (a. fumigatus) but not to components of six other fungi including al ... | 1992 | 1377093 |
| copper organo-chelators in aspergillus fumigatus and penicillium chrysogenum. | the presence of copper in the growth medium induces the biosynthesis of several low-mol-wt copper ogano-chelators in aspergillus fumigatus and penicillium chrysogenum. by use of p. chrysogenum, we were able to prepare several low-mol-wt metallothionein chelators, as well as several short-chain copper chelatins. the amino acid composition of a chelatin of mol wt approx 799 da revealed the presence of cysteine, glutamic acid, glycine, and leucine. use of a. fumigatus led to fewer copper chelators ... | 1992 | 1381937 |
| purification, characterization and partial amino acid sequences of a xylanase produced by penicillium chrysogenum. | an extracellular xylanase (1,4-beta-d-xylan xylanohydrolase, ec 3.2.1.8, endo 1,4-beta-xylanase) was found to be the major protein in the culture filtrate of penicillium chrysogenum when grown on 1% xylan. in contrast to other microorganism no xylanase multiplicity was found in p. chrysogenum under the conditions used. this enzyme was purified to homogeneity by high performance anion-exchange and size-exclusion chromatography. it had an m(r) of 35,000 as estimated by sds-page and was shown to be ... | 1992 | 1420277 |
| regulation of alpha-aminoadipate reductase from penicillium chrysogenum in relation to the flux from alpha-aminoadipate into penicillin biosynthesis. | the activity and regulation of alpha-aminoadipate reductase in three penicillium chrysogenum strains (q176, d6/1014/a, and p2), producing different amounts of penicillin, were studied. the enzyme exhibited decreasing affinity for alpha-aminoadipate with increasing capacity of the respective strain to produce penicillin. the enzyme from all three strains was inhibited by l-lysine, and the enzyme from the lowest producer, q176, was least sensitive. between ph 7.5 and 6.5, inhibition of alpha-amino ... | 1992 | 1458368 |
| fungal contamination, natural occurrence of mycotoxins and resistance for aflatoxin accumulation of some broad bean (vicia faba l.) cultivars. | using glucose-czapek's and 10% nacl glucose-czapek's agar media incubated at 28 +/- 2 degrees c, nine genera and 18 species were identified from 10 different cultivars seed of broad bean. aspergillus and penicillium were the most common genera on the two types of media used. the most common fungal species were aspergillus flavus, a. niger, a. tamarii and penicillium chrysogenum. thin-layer chromatographic analysis indicated that seeds of one cultivar only was naturally contaminated with aflatoxi ... | 1992 | 1460568 |
| transformation of filamentous fungi based on hygromycin b and phleomycin resistance markers. | 1992 | 1479914 | |
| increased prevalence of igg-induced sensitization and hypersensitivity pneumonitis (humidifier lung) in nonsmokers exposed to aerosols of a contaminated air conditioner. | specific igg antibodies against antigens of a contaminated air conditioner were estimated in serum of 134 workers of a printing company. altogether 64% of the workers investigated revealed significantly elevated levels (> 3 u/ml) of igg antibodies specific to these antigens as compared to a nonexposed control group. the occurrence of igg antibodies for microbial extracts were 25% for fusarium, 23% for penicillium notatum, 13% for alternaria tenuis, 12% for aureobasidium pullulans, 9% for sphaero ... | 1992 | 1485005 |
| [selection of penicillium chrysogenum, a producer of penicillin, on precursor-free fermentation medium]. | possible selection of p. chrysogenum producing penicillin was studied on media without an antibiotic precursor. it was shown that the selection provided a more efficient isolation of the "plus" variants synthesizing substances of the beta-lactam structure. | 1992 | 1530361 |
| ultrasonic characterization of mycelial morphology as a fractal structure. | preliminary measurements of scattering of ultrasound from filamentous microorganisms in aqueous-medium suspensions are reported. the data are used to characterize the structuring (morphology) between the organisms quantitatively by modelling the morphology in terms of fractal structures and obtaining the fractal dimension as the characteristic parameter. the fractal dimension is calculated from the slope of a log-log plot of scattered intensity versus the scattering vector magnitude. the intensi ... | 1992 | 1549898 |
| isolation and analysis of the penicillium chrysogenum phoa gene encoding a secreted phosphate-repressible acid phosphatase. | we have isolated the genomic sequence encoding a secreted phosphate-repressible acid phosphatase (phoa) from penicillium chrysogenum using synthetic oligodeoxyribonucleotide probes. nucleotide sequence data revealed that this gene consists of two exons of 192 and 1047 bp separated by an intron of 52 bp in length. a sequence encoding a putative signal peptide, resembling known signal sequences of fungi, was identified at the 5'-end of the coding sequence. northern blot analysis of total cellular ... | 1992 | 1563629 |
| the cefg gene of cephalosporium acremonium is linked to the cefef gene and encodes a deacetylcephalosporin c acetyltransferase closely related to homoserine o-acetyltransferase. | the gene (cefg) encoding the acetyl coenzyme a:deacetylcephalosporin c acetyltransferase of cephalosporium acremonium (synonym acremonium chrysogenum) c10 has been cloned. it contains two introns and encodes a protein of 444 amino acids with an m(r) of 49,269 that correlates well with the m(r) deduced by gel filtration. the cefg gene is linked to the cefef gene (encoding the bifunctional deacetoxycephalosporin c synthase/hydroxylase), but it is expressed in an orientation opposite that of the ce ... | 1992 | 1569032 |
| ultrastructure of hyphal tip bursting in penicillium chrysogenum. | hyphae around the periphery of colonies of penicillium chrysogenum were subjected to hypotonic shock by flooding them with distilled water at 25 degrees c, which provoked bursting of hyphal tips. a minority of hyphal tips (26%) burst rapidly within 1.8 s of the flooding, but bursting continued to occur such that the majority of peripheral tips (51%) were found to have burst around colonies maintained in the flooded state for 2 h. electron microscopy of burst tips indicated that cytoplasm was rel ... | 1992 | 1577253 |
| involvement of microbodies in penicillin biosynthesis. | penicillium chrysogenum strains were constructed which express a mutant acyltransferase lacking the putative targeting signal for microbody proteins. the mutated enzyme was located in vacuoles and in neighbouring cytoplasm. although acyltransferase was expressed in vivo and was active in vitro, the mutants did not produce penicillin. the results demonstrate the involvement of microbodies in penicillin production. | 1992 | 1581347 |
| substrate specificity of isopenicillin n synthase. | highly purified isopenicillin n synthase (ipns) from two sources (naturally occurring in penicillium chrysogenum and that expressed in escherichia coli via a cloned gene derived from cephalosporium acremonium) have been isolated and utilized in vitro to test synthetic modifications of the natural substrate, (l-alpha-amino-delta-adipyl)-l-cysteinyl-d-valine (acv). a very sensitive procedure utilizing the ability of beta-lactams to induce the synthesis of beta-lactamase was employed to determine w ... | 1992 | 1588566 |
| glucose biosensor based on carbon black strips. | amperometric biosensors for the determination of beta-d-glucose have been constructed. they were based on a porous matrix of carbon blacks--'ketjenblack' (kb) and 'shawinigan black' (sb) wet-proofed with polytetrafluorethylene. glucose-sensitive elements were prepared by subsequent adsorptional immobilization of 1,1'-dimethylferrocene (dmfc) and nickel-ocene (nc) on 'shawinigan black' or tetracyanoquinodimethane (tcnq) on 'ketjenblack' together with penicillium chrysogenum glucose oxidase. maxim ... | 1992 | 1632950 |
| isolation and characterization of catalase from penicillium chrysogenum. | catalase from a crude preparation of penicillium chrysogenum was isolated in a single chromatographic step by immobilized metal ion affinity chromatography (imac) on cu(ii)-chelating sepharose fast flow. a chromatographically and electrophoretically homogeneous enzyme was obtained in 89% yield. imac was found to be superior to ion-exchange, hydrophobic interaction, size-exclusion and concanavalin a affinity chromatography. analytical and preparative chromatography gave essentially the same chrom ... | 1992 | 1639925 |
| drying as one of the extreme factors for the microflora of the atmosphere. | an investigation of the effects of drying and drying-rewetting cycles under vacuum conditions of 10(-2) torr at -30 degrees c on conidia of the atmospheric strain penicillium chrysogenum from 48-77 km heights, collected by meteorological rockets found that survival and restoration of the initial physiological properties were possible through some very efficient protective cellular mechanisms. such adaptive possibilities explain the widespread diffusion of microbial cells throughout the biosphere ... | 1992 | 11539466 |
| estimation of cell volume and biomass of penicillium chrysogenum using image analysis. | a methodology for the estimation of biomass for the penicillin fermentation using image analysis is presented. two regions of hyphae are defined to describe the growth of mycelia during fermentation: (1) the cytoplasmic region, and (2) the degenerated region including large vacuoles. the volume occupied by each of these regions in a fixed volume of sample is estimated from area measurements using image analysis. areas are converted to volumes by treating the hyphae as solid cylinders with the hy ... | 1992 | 18600959 |
| rheological characterization of media containing penicillium chrysogenum. | samples from fed-batch fermentations of penicillium chrysogenum on complex medium are rheologically characterized. the behavior is well described by a power law model for which the parameters are estimates. furthermore, two types of model media are characterized and compared with the real fermentation samples. xanthan solutions are found to mimic the rheological properties of the filamentous fungi much better than carboxymethyl cellulose (cmc) solutions. | 1993 | 18601258 |
| aerobic microorganisms associated with alfalfa leafcutter bees (megachile rotundata). | characterization of microorganisms associated with alfalfa leaf-cutter bee (megachile rotundata) nectar, pollen, provisions, larval guts, and frass (excreta) in alberta demonstrated a varied aerobic microflora. yeasts were isolated frequently from nectar, pollen, and provisions but rarely from guts or frass. the most prevalent yeast taxa were: candida bombicola, cryptococcus albidus, metschnikowia reukaufii, and rhodotorula glutinis. although few filamentous fungi were found in nectar, they were ... | 1993 | 24190009 |
| 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 ... | 1993 | 24420113 |
| a simple morphologically structured model describing the growth of filamentous microorganisms. | based on the reported mechanisms for filamentous growth, a simple morphologically structured growth model is set up. the model may describe the growth of filamentous microorganisms both on a solid medium and in a submerged culture. for description of a submerged culture the model is combined with a simple population model, which is derived from a balance for the distribution function for the hyphal elements. the model is compared with experimental data for three species of filamentous microorgan ... | 1993 | 18609614 |
| detection of bacterial contamination in cultures of eucaryotic cells by gas chromatography-mass spectrometry. | the use of gas chromatography-mass spectrometry for early detection of bacterial contaminations in cultures of baker's yeast, penicillium chrysogenum, and an animal cell line was evaluated; muramic acid and characteristic cellular fatty acids were used as analytes. by analyzing branched-chain and cyclopropane-substituted fatty acids as methyl esters, staphylococcus epidermidis, bacillus subtilis, lactobacillus reuteri, enterobacter cloacae, and pseudomonas fluorescens were detected in a 500-fold ... | 1993 | 18613045 |
| morphological measurements on penicillium chrysogenum broths by rheology and filtration methods. | the morphology parameters of mycelial culture (penicillium chrysogenum) were measured and quantified by rheology and filtration methods. two of the morphology parameters obtained from rheology measurements, delta defined by the casson equation and delta* defined by intrinsic viscosity, were found to vary systematically with broth age and with the observed morphology by microscopy. three of the filtration parameters, hyphal density, kozeny constant, and index of compressibility, are demonstrated ... | 1993 | 18613112 |
| removal of lead from aqueous solutions by penicillium biomass. | the removal of lead ions from aqueous solutions by adsorption on nonliving penicillium chrysogenum biomass was studied. biosorption of the pb(+2) ion was strongly affected by ph. within a ph range of 4 to 5, the saturated sorption uptake of pb(+2) was 116 mg/g dry biomass, higher than that of activated charcoal and some other microorganisms. at ph 4.5, p. chrysogenum biomass exhibited selectivity for pb(+2) over other metal ions such as cd(+2), cu(+2), zn(+2), and as(+3) sorption preference for ... | 1993 | 18613113 |
| physiological studies related to the immobilization of penicillium chrysogenum and penicillin production. | using the production of penicillin by penicillium chrysogenum as a model system, certain physiological aspects of immobilized and free cell cultures were compared. reducing the immobilized viable spore loading (from 4 x 10(4) to 2 x 10(3) spores ml-1 gel) and initial bead diameter (from 3.5-4.0 to 1.5-2.0 mm) gave rise to an increase in the penicillin titer from 0.2 to 1.2 g l-1. using these conditions in immobilized cell culture the growth phase was prolonged and the duration of expression of t ... | 1993 | 7763358 |
| the production of cephalosporin c by acremonium chrysogenum is improved by the intracellular expression of a bacterial hemoglobin. | a dna vector for expressing an oxygen-binding heme protein (vitreoscilla hemoglobin, or vhb) in filamentous fungi was constructed and introduced into a cephalosporin c-producing strain of acremonium chrysogenum. expression of vhb in transformants was demonstrated by western immunoblot analysis and by increased carbon monoxide binding activity of cell extracts. several vhb-expressing transformants produced significantly higher yields of cephalosporin c than control strains in batch culture experi ... | 1993 | 7763915 |
| rapid release of protoplasts from eremothecium ashbyii in comparison with trichoderma reesei and penicillium chrysogenum using novozyme and funcelase. | protoplast release in eremothecium ashbyii, trichoderma reesei, and penicillium chrysogenum was achieved using commercially available enzymes, novozyme 234 and funcelase. a rapid release of protoplasts was observed in e. ashbyii, yielding nearly 4.0 x 10(7) protoplasts ml-1 in 10-35 min. the regeneration frequency of protoplasts from t. reesei, p. chrysogenum, and e. ashbyii using funcelase was 51.77, 28.32, and 7.64%, respectively, and was higher in comparison with novozyme-derived protoplasts. | 1993 | 7763961 |
| use of collagen hydrolysate as a complex nitrogen source for the synthesis of penicillin by penicillium chrysogenum. | optimal conditions for both biomass formation and penicillin synthesis by a strain of penicillium chrysogenum were determined when using a collagen-derived nitrogen source. preliminary investigations were carried out in shaken flask cultures employing a planned experimental program termed the graeco-latin square technique (auden et al., 1967). it was initially determined that up to 30% of a conventional complex nitrogen source such as cottonseed meal could be replaced by the collagen-derived nit ... | 1993 | 7764109 |
| which requirements do flow injection analyzer/biosensor systems have to meet for controlling the bioprocess? | 1993 | 7764437 | |
| two fia-based biosensor systems studied for bioprocess monitoring. | in this paper, two different fia-based biosensor systems are described for application to different biotechnologically relevant purposes. in the first system, single fiber optodes were used to determine the ph, urea and penicillin v concentrations. a two-channel system was developed for the simultaneous monitoring of different variables to increase the analysis accuracy. this system was used for monitoring the penicillin v concentration during a cultivation of penicillium chrysogenum. the second ... | 1993 | 7764442 |
| 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 ... | 1993 | 7765289 |
| inulin formation of penicillin producing industrial penicillium chrysogenum strains. | conidia of certain penicillin producing penicillium chrysogenum industrial strains produced polyfructose. two types of polyfructoses were formed by conidia of p. chrysogenum b10 from sucrose and with less yield from raffinose. ten percent of fructans were in water insoluble form attached to the outer wall of conidia. the other, ethanol precipitable fructan formed a colloid opalescent solution. the latter had inulin type beta (2-->1) bonds--identified by 13c nmr spectroscopy--between fructose mol ... | 1993 | 7976214 |
| 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 ... | 1993 | 7680578 |
| 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 ... | 1993 | 8103029 |
| calcium homeostasis, signalling and protein phosphorylation during calcium-induced conidiation in penicillium notatum. | cytosolic free calcium concentration [ca2+]c of protoplasts from penicillium notatum was measured using the permeant acetoxy ester (quin-2-am) of the calcium-chelating fluorescent dye quin-2. low uptake of the ester occurred at ph 5.8-7.0 and its subsequent hydrolysis was low. uptake was promoted by an external ph of 5.0 and significant hydrolysis to quin-2 achieved by adjustment of the internal ph to 7.2, which was near the optimum of the carboxylic esterases responsible for the hydrolysis. upt ... | 1993 | 8126432 |
| fungal flora and mycotoxins of six kinds of nut seeds for human consumption in saudi arabia. | a wide range of moulds representing several genera and species, was recorded in this study from 5 seed samples of each almond, cashew nut, chestnut, hazelnut, pistachio nut and walnut collected from different markets in ar' ar, saudi arabia. the total counts of fungi were widely fluctuated between 1960-7704 and 1948-7434 colonies/g dry seeds on glucose-czapek's and glycerol agar media at 28 degrees c, respectively, and represented twenty genera, 53 species and 2 varieties of fungi. the prevalent ... | 1993 | 8159218 |
| filamentous fungi and mycotoxin detected in coconut. | fifty-nine species and one variety belonging to 25 genera of fungi were isolated from 25 coconut samples on glucose-czapek's (25 genera and 55 species + 1 variety) and dichloran-glycerol (8 genera and 32 species + 1 variety) agar media at 28 degrees c. the common fungi on both media used were aspergillus flavus, a. niger, penicillium chrysogenum and cladosporium cladosporioides. on glucose-czapek's agar, a. flavus var. columnaris, p. oxalicum, alternaria alternata, rhizopus stolonifer and tricho ... | 1993 | 8212938 |
| the requirement for subunit interaction in the production of penicillium chrysogenum acyl-coenzyme a:isopenicillin n acyltransferase in escherichia coli. | subunit interaction in the formation of active acyl-coenzyme a:isopenicillin n acyltransferase (at) has been investigated. various at derivatives were produced from altered penicillium chrysogenum pende genes placed in escherichia coli expression systems. the regions of pende encoding the alpha (11 kda) and beta (29 kda) at subunits were separated at the dna level by linker insertion at the region encoding gly102/cys103. synthesis of at from the resulting two-cistron mrna resulted in active alph ... | 1993 | 8224864 |
| survey of mycoflora and mycotoxins of some dried fruits in egypt. | fifty-five species and two varieties appertaing to 23 genera were collected and identified from 4 samples of dried fig and 3 dried samples of each of apricot, plum and raisin. forty-nine species and two varieties belonging to 20 genera were isolated on 1% glucose-czapek's while 31 species and one variety belonging to 16 genera were isolated on 40% sucrose-czapek's agar medium at 28 +/- 2 degrees c. penicillium, aspergillus and cladosporium were the common genera on the two types of media used. a ... | 1993 | 8229671 |
| resolution of four large chromosomes in penicillin-producing filamentous fungi: the penicillin gene cluster is located on chromosome ii (9.6 mb) in penicillium notatum and chromosome i (10.4 mb) in penicillium chrysogenum. | four chromosomes were resolved by pulsed field gel electrophoresis in penicillium notatum (10.8, 9.6, 6.3 and 5.4 mb in size) and in five different strains of penicillium chrysogenum (10.4, 9.6, 7.3 and 6.8 mb in the wild type). small differences in size were found between the four chromosomes of the five p. chrysogenum strains. the penicillin gene cluster was localized by hybridization with a pcbab probe to chromosome ii of p. notatum and to chromosome i of all p. chrysogenum strains except the ... | 1993 | 8264531 |
| 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 ... | 1993 | 8271157 |
| gene manipulation by protoplast fusion and penicillin production by penicillium chrysogenum. | hybrids have been obtained by protoplast fusion of nitrate-nonutilizing cnx- and acetate-nonutilizing fac- mutants of penicillium chrysogenum strains 4/95 and 26/818, respectively. induced haplodization of the hybrids allowed the recovery of stable segregants, which were screened for penicillin production. the penicillin-producing segregants showed a wide range of titers that reached for a certain mutant to 290-390% increase above the parent strains. | 1993 | 8323265 |
| the isopenicillin-n acyltransferase of penicillium chrysogenum has isopenicillin-n amidohydrolase, 6-aminopenicillanic acid acyltransferase and penicillin amidase activities, all of which are encoded by the single pende gene. | the isopenicillin-n acyltransferase of penicillium chrysogenum catalyzes the conversion of the biosynthetic intermediate isopenicillin n to the hydrophobic penicillins. the isopenicillin-n acyltransferase copurified with the acyl-coa:6-aminopenicillanic acid (6-apa) acyltransferase activity which transfers an acyl residue from acyl-coa derivatives (e.g. phenylacetyl-coa, phenoxyacetyl-coa) to 6-apa. other thioesters of phenylacetic acid were also used as substrates. an amino acid sequence simila ... | 1993 | 8344300 |
| murine monoclonal antibodies to glycoprotein antigens of aspergillus fumigatus show cross-reactivity with other fungi. | six monoclonal antibodies produced against aspergillus fumigatus were studied for their cross-reactivity against other fungal antigens from related and unrelated organisms. five of the monoclonal antibodies reacted with glycoprotein antigens as evidenced by their binding to concanavalin a, although one did not react with concanavalin a. the reactivities of the monoclonal antibodies with various antigens were studied by biotin-avidin linked immunosorbent assay and western blots. the results indic ... | 1993 | 8354480 |
| mycoflora and natural occurrence of mycotoxins in tobacco from cigarettes in egypt. | forty-two species and 4 varieties belonging to 21 genera were collected from 40 tobacco samples on glucose- and cellulose-czapek's agar at 28 degrees c and 45 degrees c. the most common mesophiles (at 28 degrees c) in tobacco on the two types of media were: aspergillus flavus, a. flavus var. columnaris, a. fumigatus, a. niger, penicillium chrysogenum and p. funiculosum. two samples were heavily contaminated with members of fusarium (f. moniliforme, f. oxysporum, f. solani). some fungi were encou ... | 1993 | 8368025 |
| on the production of alpha, beta-heterodimeric acyl-coenzyme a: isopenicillin n-acyltransferase of penicillium chrysogenum. studies using a recombinant source. | a high level e. coli expression system has been constructed for the penicillium chrysogenum pende gene, which encodes the acyl-coenzyme a: isopenicillin n-acyltransferase (at) enzyme. induction of overexpression of recombinant at (recat) by increasing the growth temperature of the host adversely affected solubility and activity of the at enzyme. addition of isopropylthio-beta-d-galactopyranoside (iptg) at decreased growth temperatures (less than 32 degrees c) resulted in the overproduction of so ... | 1993 | 8384123 |
| fructose-2,6-bisphosphate level and beta-lactam formation in penicillium chrysogenum. | the rate of penicillin formation in the medium containing lactose as sole carbon source markedly decreased after addition of glucose but at the same time the growth rate of fungal mycelium increased. significant correlation was found between the formation of penicillin and the intracellular concentration of fructose-2,6-bisphosphate. it appears that penicillin production is influenced by the level of fructose-2,6-bisphosphate. | 1993 | 8386764 |
| investigations into the post-translational modification and mechanism of isopenicillin n:acyl-coa acyltransferase using electrospray mass spectrometry. | electrospray mass spectrometry (e.s.m.s.) was used to confirm the position of the post-translational cleavage of the isopenicillin n:acyl-coa acyltransferase preprotein to give the alpha- and beta-subunits. the e.s.m.s. studies suggested partial modification of the alpha-subunit in vivo by exogenously added substituted acetic acids. e.s.m.s. has also allowed the observation in vitro of the transfer of the acyl group from several acyl-coas to the beta-subunit. n.m.r. data for the coa species have ... | 1993 | 8396910 |
| new cause for false-positive results with the pastorex aspergillus antigen latex agglutination test. | the pastorex aspergillus antigen test for detection of aspergillus galactomannan antigen in the sera of patients with invasive aspergillosis is used in many clinical laboratories. a serum sample contaminated with penicillium chrysogenum gave a strongly positive reaction (1:128) which was heat stable, was not eliminated by pronase treatment, and was not detected by a normal rabbit globulin control. this observation was shown to be due to cross-reactions of the monoclonal antibody eb-a2 used by th ... | 1993 | 8408572 |
| genomic sequence of mitochondrial genes coding for atpase subunit 6 and small subunit ribosomal rna from penicillium chrysogenum: a key for molecular systematics on fungi. | 1993 | 8414999 | |
| subcellular compartmentation of penicillin biosynthesis in penicillium chrysogenum. the amino acid precursors are derived from the vacuole. | the cellular localization of the origin of alpha-aminoadipate used in penicillin biosynthesis and the first enzymic step in penicillium chrysogenum involved, delta-(alpha-aminoadipyl)-l-cysteinyl-d-valine synthetase (acvs), has been studied. subcellular fractions were obtained from protoplasts of a high penicillin-producing strain upon lysis by triton x-100, and vacuoles purified from them. they were identified by the aid of alpha-mannosidase as a marker enzyme, by the presence of polyphosphate, ... | 1993 | 8416970 |
| 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. ... | 1993 | 8416976 |
| 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. | 1993 | 8431952 |
| monitoring airborne fungal spores in an experimental indoor environment to evaluate sampling methods and the effects of human activity on air sampling. | aerobiological monitoring was conducted in an experimental room to aid in the development of standardized sampling protocols for airborne microorganisms in the indoor environment. the objectives of this research were to evaluate the relative efficiencies of selected sampling methods for the retrieval of airborne fungal spores and to determine the effect of human activity on air sampling. dry aerosols containing known concentrations of penicillium chrysogenum spores were generated, and air sample ... | 1993 | 8439150 |
| microculture model studies on the effect of sorbic acid on penicillium chrysogenum, cladosporium cladosporioides and ulocladium atrum at different ph levels. | the minimum growth-inhibitory concentration of sorbic acid has been determined for penicillium chrysogenum, cladosporium cladosporioides and ulocladium atrum at ph 4.1-7.6 by using a microculture technique. this technique had earlier been applied to bacteria and candida albicans and gave very reliable minimum inhibitory values. this investigation has shown that it is suitable also for determination of mould growth. the minimum inhibitory concentrations of sorbic acid were at the tested ph levels ... | 1993 | 8444649 |
| purification of pseudomonas putida acyl coenzyme a ligase active with a range of aliphatic and aromatic substrates. | acyl coenzyme a (acyl-coa) ligase (acyl-coa synthetase [acoas]) from pseudomonas putida u was purified to homogeneity (252-fold) after this bacterium was grown in a chemically defined medium containing octanoic acid as the sole carbon source. the enzyme, which has a mass of 67 kda, showed maximal activity at 40 degrees c in 10 mm k2po4h-napo4h2 buffer (ph 7.0) containing 20% (wt/vol) glycerol. under these conditions, acoas showed hyperbolic behavior against acetate, coa, and atp; the kms calcula ... | 1993 | 8476289 |
| mycoflora and mycotoxin of hazelnut (corylus avellana l.) and walnut (juglans regia l.) seeds in egypt. | fifty-one species and 3 varieties appertaining to 20 genera were collected from 20 samples of each of hazelnut and walnut seeds on glucose- and 40% (w/v) sucrose-czapek's agar at 25 degrees c and 45 degrees c with the most common mesophiles were aspergillus flavus, a. fumigatus, a. niger, cladosporium cladosporioides, c. herbarum, penicillium chrysogenum, p. citrinum and p. oxalicum. fusarium (represented by f. equiseti, f. moniliforme and f. oxysporum) was recovered from walnut seeds in moderat ... | 1993 | 8480455 |
| cloning and structural organization of a xylanase-encoding gene from penicillium chrysogenum. | the filamentous fungus, penicillium chrysogenum, is able to grow on xylan as a sole carbon source. under these conditions, high levels of a xylanase (xylp) are secreted into the medium. after purification and characterization of this enzyme, we have isolated both the encoding cdna and the genomic sequence by using oligodeoxyribonucleotides derived from partial amino acid (aa) sequences of the purified enzyme. the gene is approximately 1.6 kb in length, and comparison of the nucleotide (nt) seque ... | 1993 | 8482539 |
| expression of the 3-phosphoglycerate kinase gene (pgka) of penicillium chrysogenum. | the sequence of the penicillium chrysogenum pgka gene promoter was determined up to 952 nucleotides (nt) 5' to the major transcriptional start point (position +1), and contains a 38 bp pyrimidine-rich region within which transcription initiates at this and two minor sites (-11, -23). a 21 bp segment (-99 to -79) closely matches a region which is essential for the expression of the aspergillus nidulans pgka gene. a further region was found with similarity to sequences in other a. nidulans promote ... | 1994 | 8190080 |
| intermediate channeling between atp sulfurylase and adenosine 5'-phosphosulfate kinase from rat chondrosarcoma. | biosynthesis of the activated sulfate donor paps (3'-phosphoadenosine 5'-phosphosulfate) involves the sequential action of two enzyme activities. atp sulfurylase catalyzes the formation of aps (adenosine 5'-phosphosulfate) from atp and free sulfate, and aps is then phosphorylated by aps kinase to produce paps. using rat chondrosarcoma atp sulfurylase and aps kinase, a newly developed assay system, which permits measuring the accumulation of both aps and paps in the presence of both enzyme activi ... | 1994 | 8204616 |
| investigation on the toxicity of fungi from rootstock snacks. | chicken embryo bioassay was used to monitor the toxicity of extracts from rootstock snack samples during a 210-day storage period. results show that the relative toxicity values which were initially very low increased significantly as from 120th day (when 32% mortality was recorded) up till the last day when 73% was obtained. toxicity of extracts from axenic cultures of 12 fungal species isolated from the snack samples was also determined. the strains of aspergillus chevalieri, rhizopus nigrican ... | 1994 | 8145803 |
| the thioredoxin system of penicillium chrysogenum and its possible role in penicillin biosynthesis. | penicillium chrysogenum is an important producer of penicillin antibiotics. a key step in their biosynthesis is the oxidative cyclization of delta-(l-alpha-aminoadipyl)-l-cysteinyl-d-valine (acv) to isopenicillin n by the enzyme isopenicillin n synthase (ipns). bis-acv, the oxidized disulfide form of acv is, however, not a substrate for ipns. we report here the characterization of a broad-range disulfide reductase from p. chrysogenum that efficiently reduces bis-acv to the thiol monomer. when co ... | 1994 | 8106340 |
| an 'instant gene bank' method for gene cloning by mutant complementation. | we describe a new method of gene cloning by complementation of mutant alleles which obviates the need for construction of a gene library in a plasmid vector in vitro and its amplification in escherichia coli. the method involves simultaneous transformation of mutant strains of the fungus aspergillus nidulans with (i) fragmented chromosomal dna from a donor species and (ii) dna of a plasmid without a selectable marker gene, but with a fungal origin of dna replication ('helper plasmid'). transform ... | 1994 | 8121403 |
| [biogenesis of 6-aminopenicillanic acid (6-apa) and penicillin in penicillium chrysogenum: effect of the biocatalyst chrysin]. | the investigations were concerned with the examination of the effect of chrysin, a biocatalyst on the 6-apa and penicillin biogenesis in penicillium chrysogenum (thom), panlabs p-5 strain. chrysin, a natural plant biocatalyst was used to increase the large scale production of penicillin. the experiments were conducted on chemically defined media under conditions determined for this strain in shake flask fermentations. the production of 6-apa and penicillin g was checked and confirmed by hplc. th ... | 1994 | 7695452 |
| asparagine-linked carbohydrate of penicillium notatum phospholipase b. | the asparagine-linked sugar chains of phospholipase b from penicillium notatum were released by hydrazinolysis. the carbohydrate components were re-n-acetylated and then reductively aminated with 2-aminopyridine. the pyridyl-aminated derivatives were analyzed by size-fractionation and reverse-phase hplc. the results indicated that the enzyme contains only one kind of oligosaccharide. the carbohydrate was purified by hplc, and then subjected to nmr and ms analyses for determination of its structu ... | 1994 | 7702655 |
| cloning and sequencing of phospholipase b gene from the yeast torulaspora delbrueckii. | the extracellular phospholipase b gene from baker's yeast torulaspora delbrueckii was cloned and sequenced. analysis of dna sequence data revealed an open reading frame (orf) encoding a 649-amino acid protein, that included amino acid sequences obtained from the purified enzyme. comparison of these sequence data with the n-terminal amino acid sequence of the enzyme indicated that this secreted protein is synthesized as a large precursor with a 21-amino acid n-terminal extension to the mature enz ... | 1994 | 8001766 |
| aerobic catabolism of phenylacetic acid in pseudomonas putida u: biochemical characterization of a specific phenylacetic acid transport system and formal demonstration that phenylacetyl-coenzyme a is a catabolic intermediate. | the phenylacetic acid transport system (pats) of pseudomonas putida u was studied after this bacterium was cultured in a chemically defined medium containing phenylacetic acid (pa) as the sole carbon source. kinetic measurement was carried out, in vivo, at 30 degrees c in 50 mm phosphate buffer (ph 7.0). under these conditions, the uptake rate was linear for at least 3 min and the value of km was 13 microm. the pats is an active transport system that is strongly inhibited by 2,4-dinitrophenol, 4 ... | 1994 | 8002592 |
| improved expression of a hybrid streptomyces clavuligerus cefe gene in penicillium chrysogenum. | a hybrid cefe gene, encoding penicillin n expandase, was constructed by fusing the promoter sequences, pcp, and terminator sequences, pct from the penicillium chrysogenum pcbc gene to the open reading frame (orf), cefeorf, from the streptomyces clavuligerus cefe gene. the resulting hybrid gene, pcp/cefe'orf/pct, differed from a previously reported hybrid cefe gene contained on plasmid pps65. the latter gene, pcp/cefe'orf/sct, contained the pcp sequences fused to the s. clavuligerus cefe orf stil ... | 1994 | 8010669 |
| catabolism of lysine in penicillium chrysogenum leads to formation of 2-aminoadipic acid, a precursor of penicillin biosynthesis. | penicillium chrysogenum l2, a lysine auxotroph blocked in the early steps of the lysine pathway before 2-aminoadipic acid, was able to synthesize penicillin when supplemented with lysine. the amount of penicillin produced increased as the level of lysine in the media was increased. the same results were observed in resting-cell systems. catabolism of [u-14c]lysine by resting cells and batch cultures of p. chrysogenum l2 resulted in the formation of labeled saccharopine and 2-aminoadipic acid. fo ... | 1994 | 8031073 |
| the saccharomyces cerevisiae plb1 gene encodes a protein required for lysophospholipase and phospholipase b activity. | several enzymes with lysophospholipase/phospholipase b activity have been described from the budding yeast saccharomyces cerevisiae. in vitro, these enzymes are capable of hydrolyzing all phospholipids that can be extracted from yeast cells. two forms of the enzyme have been isolated from plasma membranes and a third from culture supernatants and the periplasmic space, but their biological roles have not been determined. these highly glycosylated enzymes were reported to have very similar cataly ... | 1994 | 8051052 |
| cloning and sequencing of atp sulfurylase from penicillium chrysogenum. identification of a likely allosteric domain. | fungal (penicillium chrysogenum) and yeast (saccharomyces cerevisiae) atp sulfurylases were shown to have very similar kinetic and chemical properties except that the fungal enzyme (a) contains a highly reactive cys residue (sh-1) whose modification results in sigmoidal velocity curves (renosto, f., martin, r. l., and segel, i. h. (1987) j. biol. chem. 262, 16279-16288) and (b) is allosterically inhibited by 3'-phosphoadenosine 5'-phosphosulfate (paps), while the yeast enzyme displays neither of ... | 1994 | 8051058 |