Publications
| Title | Abstract | Year Filter | PMID(sorted ascending) Filter |
|---|
| isolation and identification of a new cephem compound from penicillium chrysogenum strains expressing deacetoxycephalosporin c synthase activity. | 1995 | 7775275 | |
| a heuristic approach to the analysis of enzymic catalysis: reaction of delta-(l-alpha-aminoadipoyl)-l-cysteinyl-d-alpha-aminobutyrate and delta-(l-alpha-aminoadipoyl)-l-cysteinyl-d-allylglycine catalyzed by isopenicillin n synthase isozymes. | isopenicillin n synthase (ipns) catalyzes the oxidative cyclization of delta-(l-alpha-aminoadipoyl)-l-cysteinyl-d-valine to isopenicillin n. it is proposed that the multiple products produced from certain substrate analogues result from pathway branching after formation of a ferryl oxene intermediate. we have been interested in ascertaining the reasons for multiple product formation. one possibility is that the products are predisposed toward formation once the beta-lactam ring and the ferryl ox ... | 1995 | 7779800 |
| molecular cloning and analysis of nre, the major nitrogen regulatory gene of penicillium chrysogenum. | we have isolated the penicillium chrysogenum nre gene which is homologous to the major nitrogen regulatory genes area from aspergillus nidulans and nit-2 from neurospora crassa. overall, nre shows 60% identity to area and 30% identity to nit-2 at the amino-acid level. the gene encodes a protein of 835 amino-acid residues and contains a single cys2/cys2-type zinc finger with an adjacent basic region and a putative acidic activation region. in the dna-binding domain, 98% of the amino-acid residues ... | 1995 | 7788718 |
| a reporter gene analysis of penicillin biosynthesis gene expression in penicillium chrysogenum and its regulation by nitrogen and glucose catabolite repression. | vectors which possess a truncated niad gene encoding nitrate reductase were developed to allow targeted gene integration during transformation of an niad mutant penicillium chrysogenum host. the penicillium genes pcbc and penab are immediately adjacent to each other and are divergently transcribed, with an intergenic control region serving as their promoters. gene fusions were constructed with a reporter gene, uida, which encodes beta-glucuronidase. the pcbc-penab intergenic region was fused to ... | 1994 | 7811083 |
| expression of genes and processing of enzymes for the biosynthesis of penicillins and cephalosporins. | the genes pcbab, pcbc and pende encoding the enzymes (alpha-aminoadipyl-cysteinyl-valine synthetase, isopenicillin n synthase and isopenicillin n acyltransferase, respectively) involved in the biosynthesis of penicillin have been cloned from penicillin chrysogenum and aspergillus nidulans. they are clustered in chromosome i (10.4 mb) of p. chrysogenum, in chromosome ii of penicillium notatum (9.6 mb) and in chromosome vi (3.0 mb) of a. nidulans. each gene is expressed as a single transcript from ... | 1994 | 7847890 |
| a general method for immobilization of glycoproteins on regenerable immobilized metal-ion carriers: application to glucose oxidase from penicillium chrysogenum and horseradish peroxidase. | a general method for immobilization of glycoproteins on immobilized metal-ion carriers is described. the method includes oxidation of the carbohydrate moiety of the glycoprotein with potassium periodate, covalent modification with histidine and immobilization on bivalent metal ion-iminodiacetic acid-agarose. the method is exemplified with horseradish peroxidase and glucose oxidase from penicillium chrysogenum. the modified and immobilized enzymes are stable for at least 2 months at 4 degrees c. ... | 1994 | 7917065 |
| improvement of heavy metal biosorption by mycelial dead biomasses (rhizopus arrhizus, mucor miehei and penicillium chrysogenum): ph control and cationic activation. | fungal mycelial by-products from fermentation industries present a considerable affinity for soluble metal ions (e.g. zn, cd, ni, pb, cr, ag) and could be used in biosorption processes for purification of contaminated effluents. in this work the influence of ph on sorption parameters is characterized by measuring the isotherms of five heavy metals (ni, zn, cd, ag and pb) with rhizopus arrhizus biomass under ph-controlled conditions. the maximum sorption capacity for lead was observed at ph 7.0 ( ... | 1994 | 7917420 |
| structural and functional properties of plasma membranes from the filamentous fungus penicillium chrysogenum. | functional plasma membranes from the filamentous fungus penicillium chrysogenum have been isolated with the objective of studying transport processes. the isolation procedure consists of three steps, namely homogenization of cells with a braun msk homogenizer, followed by percoll gradient centrifugation and floatation of membranes in a three-step nycodenz gradient. this method can be applied to strains which differ significantly in morphology and penicillin-production capacity. plasma membranes ... | 1994 | 7925375 |
| antagonistic activity of the food-related filamentous fungus penicillium nalgiovense by the production of penicillin. | defined strains of the genus penicillium used as starter cultures for food and strains isolated from mold-fermented foods were analyzed for their ability to inhibit the growth of micrococcus luteus dsm 348 used as an indicator organism. most of the strains belonging to the species penicillium nalgiovense showed antagonistic activity in agar diffusion assays. penicillium camemberti and penicillium roqueforti strains proved to be inactive in these tests. the inhibitory substance excreted by p. nal ... | 1994 | 7944371 |
| an acid phosphatase from aspergillus ficuum has homology to penicillium chrysogenum phoa. | three secreted acid phosphatases had previously been characterized from aspergillus ficuum grown under conditions of limited phosphate. one of these could not be readily separated from afphyb, a ph 2.5 optimum acid phosphatase with phytase activity. from extensive protein sequence analysis and subsequent cloning of the gene, we have shown that the afphyb protein fraction contains a fourth secreted acid phosphatase (afphoa) that has 64% homology to a phosphate-repressible acid phosphatase from pe ... | 1994 | 7945393 |
| 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 |
| 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 |
| mold allergy in adana, turkey. | in order to investigate the possible role of molds in respiratory allergy, skin prick tests with the extracts of 19 different fungi were applied to 614 respiratory allergic patients. indoor mold samples of some of these mold sensitive patients are also presented. most of the patients (72.6%) had extrinsic asthma while 27.4% having allergic rhinitis. the diagnosis was based on history, clinical examination and skin prick test which was done according to peppy's method. aspergillus fumigatus was t ... | 1994 | 8059675 |
| a glucose-activated electron transfer system in the plasma membrane stimulates the h(+)-atpase in penicillium cyclopium. | hyphal cells of three fungal species of the genus penicillium reduced the nonpermeable, external electron acceptor hexabromoiridate iv (hbi iv). in penicillium cyclopium, the rate of hbi iv reduction by hyphal cells was drastically increased by the addition of beta-glucose. the stimulation showed high specificity for this sugar and did not require its uptake and cellular metabolism. cell wall oxidases (e.g., glucose oxidase) did not seem to be involved in the reduction of hbi iv, as no measurabl ... | 1994 | 8071221 |
| the penicillium chrysogenum and aspergillus nidulans weta developmental regulatory genes are functionally equivalent. | aspergillus nidulans and penicillium chrysogenum are related fungi that reproduce asexually by forming multicellular conidiophores and uninucleate conidia. in a. nidulans, spore maturation is controlled by the weta (aweta) regulatory gene. we cloned a homologous gene (pweta) from p. chrysogenum to determine if spore maturation is regulated by a similar mechanism in this species. the pweta and aweta genes are similar in structure and functional organization. the inferred polypeptides share 77% ov ... | 1994 | 8078481 |
| acyl-coenzyme a: isopenicillin n acyltransferase from penicillium chrysogenum: effect of amino acid substitutions at ser227, ser230 and ser309 on proenzyme cleavage and activity. | using a high level escherichia coli expression system for the penicillium chrysogenum pende gene, we have produced acyl-coenzyme a: isopenicillin n acyltransferase (at) enzymes containing amino acid substitutions at three conserved ser residues. chosen for study based on amino acid sequence homologies to other proteins, ser227, ser230 and ser309 were changed to cys or ala to assess amino acid side chain involvement in proenzyme cleavage and at enzyme mechanism. substitutions at ser230 had no eff ... | 1994 | 8082826 |
| serine 228 is essential for catalytic activities of 85-kda cytosolic phospholipase a2. | the ca(2+)-sensitive cytosolic phospholipase a2 (cpla2) displays both a phospholipase a2 and a lysophospholipase activity. numerous hydrolases, including lipases, catalyze the hydrolysis of ester bonds by means of an active site triad of amino acids that includes a serine or a cysteine residue. we have examined whether human cpla2 belongs to this class of enzymes by using site-directed mutagenesis. although chemical inactivation of cpla2 by the sulfhydryl reagent n-ethylmaleimide made it appear ... | 1994 | 8083230 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| enzymatic synthesis of hydrophobic penicillins. | our knowledge of the enzymes and genes involved in the biosynthesis of beta-lactam antibiotics has increased notably in the last decade. the purification to homogeneity of some of these proteins as well as their biochemical characterization has allowed some of them to be used for synthesizing many different penicillins and cephalosporin-like products in vitro. in this report we describe the most important advances in this field, placing special emphasis on the enzymatic synthesis of hydrophobic ... | 1995 | 8557558 |
| cloning, structural organization and regulation of expression of the penicillium chrysogenum paf gene encoding an abundantly secreted protein with antifungal activity. | an abundantly secreted, highly basic 12-kda protein (paf) was purified from the culture medium of penicillium chrysogenum (pc). based on the n-terminal amino acid (aa) sequence of the protein, an oligodeoxyribonucleotide probe was derived and used for amplification of the encoding cdna by pcr. this cdna fragment encodes a cys-rich preproprotein of 92 aa which appears to be processed to a mature product of 55 aa. the deduced aa sequence of the preproprotein reveals 42.6% identity to an antifungal ... | 1995 | 8566771 |
| [the clinical picture of mycotic complications in hiv-infected patients]. | mycotic complications were registered in 21 out of 37 hiv-infected subjects. oropharyngeal candidiasis was most common. it occurred prior to or concurrently with esophageal and skin candidiasis, fungemia, meningoencephalitis and disseminated lesions. with immunodeficiency progression, the prevalence and severity of mycosis go up. the causing fungi vary in great range: candida albicans, candida krusei. candida tropicalis, candida pseudotropicalis, candida parapsilosis. cryptococcus neoformans, rh ... | 1995 | 8577107 |
| nre, the major nitrogen regulatory protein of penicillium chrysogenum, binds specifically to elements in the intergenic promoter regions of nitrate assimilation and penicillin biosynthetic gene clusters. | nre, the nitrogen regulatory protein of penicillium chrysogenum, contains a single cys2/cys2-type zinc-finger motif followed immediately by a highly basic region. the zinc-finger domain was expressed to escherichia coli as a fusion protein with beta-galactosidase. in order to test the putative dna-binding ability of nre, the intergenic promoter region of the nitrate reductase/nitrite reductase gene cluster (niia-niad) of penicillium was sequenced. our results show that nre is a dna-binding prote ... | 1995 | 8590470 |
| detection of a protein which binds specifically to the upstream region of the pcbab gene in penicillium chrysogenum. | the upstream region of the pcbab gene from penicillium chrysogenum was screened for protein-binding sites using an electromobility shift assay. a specific protein/dna interaction was detected within a fragment covering the region -387 to -242 relative to the pcbab translational start codon. the appearance of this protein and pcbab mrna in culture extracts occurred at the same time point in fermentations, suggesting that the protein might be a transcription activator. the putative upstream activa ... | 1995 | 8590471 |
| mutational analysis reveals dispensability of the n-terminal region of the aspergillus transcription factor mediating nitrogen metabolite repression. | mutational analysis has enabled identification and localization of an upstream exon of the area gene of aspergillus nidulans mediating nitrogen metabolite repression. a mutation in the initiation codon and frameshift mutations, which revert by restoration of the reading frame, established the coding role of the exon and mutations affecting intron splicing in conjunction with dna sequencing of reverse transcriptase polymerase chain reaction (rt-pcr) products localized the coding region intron. th ... | 1995 | 8596437 |
| autonomously replicating plasmids carrying the ama1 region in penicillium chrysogenum. | plasmid vectors containing the ama1 sequence transformed with high efficiency and replicated autonomously in penicillium chrysogenum. the efficiency of transformation of p. chrysogenum was related to the length of the ama1 fragment used for constructing the different autonomously replicating plasmids. one of the two palindromic inverted repeats of ama1 (the 2.2-kb sali-hindiii fragment) is sufficient to confer autonomous replication and a high transformation efficiency. deletion of the 0.6-kb ce ... | 1996 | 8625429 |
| bms-182123, a fungal metabolite that inhibits the production of tnf-alpha by macrophages and monocytes. | a fungal metabolite, bms-182123, which inhibited bacterial endotoxin-induced production of tumor necrosis factor (tnf-alpha) in murine macrophages and human peripheral blood monocytes (in vitro), was isolated from the culture broth of penicillium chrysogenum strain v39673. the effective bms-182123 concentration (ic50) resulting in 50% inhibition of lipopolysaccharide-induced tnf-alpha production in murine macrophages and human monocytes was 600 ng/ml and 4.0 microgram/ml, respectively. bms-18212 ... | 1996 | 8626236 |
| improved fiber-optic chemical sensor for penicillin. | an optical penicillin biosensor is described, based on the enzyme penicillinase. the sensor is fabricated by selective photodeposition of analyte-sensitive polymer matrices on optical imaging fibers. the penicillin-sensitive matrices are fabricated by immobilizing the enzyme as micrometer-sized particles in a polymer hydrogel with a covalently bound ph indicator. an array of penicillin-sensitive and ph-sensitive matrices are fabricated on the same fiber. this array allows for the simultaneous, i ... | 1995 | 8633784 |
| identification of a major cis-acting dna element controlling the bidirectionally transcribed penicillin biosynthesis genes acva (pcbab) and ipna (pcbc) of aspergillus nidulans. | the beta-lactam antibiotic penicillin is produced as a secondary metabolite by some filamentous fungi. in this study, the molecular regulation of the aspergillus (emericella) nidulans penicillin biosynthesis genes acva (pcbab) and ipna (pcbc) was analyzed. acva and ipna are divergently oriented and separated by an intergenic region of 872 bp. translational fusions of acva and ipna with the two escherichia coli reporter genes lacz and uida enabled us to measure the regulation of both genes simult ... | 1996 | 8682797 |
| sulfate transport in penicillium chrysogenum plasma membranes. | transport studies with penicillium chrysogenum plasma membranes fused with cytochrome c oxidase liposomes demonstrate that sulfate uptake is driven by the transmembrane ph gradient and not by the transmembrane electrical potential. ca2+ and other divalent cations are not required. it is concluded that the sulfate transport system catalyzes the symport of two protons with one sulfate anion. | 1996 | 8682803 |
| beta-lactams. | 1995 | 8688626 | |
| mutants blocked in penicillin biosynthesis show a deletion of the entire penicillin gene cluster at a specific site within a conserved hexanucleotide sequence. | the organization of the genes of the penicillin cluster has been studied in three different mutants of p. chrysogenum impaired in penicillin biosynthesis. the three blocked mutants (derived from the parental strain p. chrysogenum bb-1) lacked the genes pcbab, pcbc and pende of the penicillin biosynthetic pathway and were unable to form isopenicillin n synthase and isopenicillin n acyltransferase. all strains were identified as p. chrysogenum derivatives by fingerprinting analysis with (gtg)n as ... | 1996 | 8703430 |
| the aspergillus nidulans penicillin-biosynthesis gene aat (pende) is controlled by a ccaat-containing dna element. | analysis of the promoter of the penicillin biosynthesis aat (pende) gene of aspergillus nidulans using band-shift assays led to the identification of a ccaat-containing dna element which was specifically bound by a protein (complex). the identified dna element was localised about 250 bp upstream of the transcriptional-start sites of aat. substitution of the ccaat core sequence by gatcc led to a fourfold reduction of expression of an aat-lacz gene fusion. the identified binding site thus was func ... | 1996 | 8706667 |
| characterization of a penicillium chrysogenum gene encoding a pacc transcription factor and its binding sites in the divergent pcbab-pcbc promoter of the penicillin biosynthetic cluster. | previous work established that ph regulation of gene expression in aspergillus nidulans, a major determinant of penicillin biosynthesis, is mediated by the zinc-finger transcription factor pacc, an activator of transcription of the isopenicillin n synthase gene. we characterize here the pacc gene from the efficient penicillin producer penicillium chrysogenum, which functionally complements an a. nidulans pacc null mutation. it encodes a 641-residue polypeptide showing 64% identify to a. nidulans ... | 1996 | 8736532 |
| basic amino acid transport in plasma membrane vesicles of penicillium chrysogenum. | the characteristics of the basic amino acid permease (system vi) of the filamentous fungus penicillium chrysogenum were studied in plasma membranes fused with liposomes containing the beef heart mitochondrial cytochrome c oxidase. in the presence of reduced cytochrome c, the hybrid membranes accumulated the basic amino acids arginine and lysine. inhibition studies with analogs revealed a narrow substrate specificity. within the external ph range of 5.5 to 7.5, the transmembrane electrical potent ... | 1996 | 8763922 |
| effect of medium components and metabolic inhibitors on beta-galactosidase production and secretion by penicillium notatum 1. | factors affecting the beta-galactosidase production by penicillium notatum 1 were studied using fermentation media of different chemical composition. the medium containing lactose, salts, peptone and yeast extract with initial ph 2.5 was selected as the best for enzyme production. monobasic ammonium phosphate (0.9%) was found to be the best inorganic nitrogen source for lactase production. various extraction media and metabolic inhibitors were examined for effective releasing of beta-galactosida ... | 1996 | 8819842 |
| composition and toxigenic potential of the mould population on dry-cured iberian ham. | the fungal population on dry-cured iberian ham can be essential to the development of the product's unique characteristics, but health hazards due to mycotoxins may be significant. we examined the natural fungal population of iberian hams during ripening at three different locations. chloroform extracts from 59 selected isolates were tested for toxicity to brine shrimp larvae and vero cells, for mutagenicity in the ames test and for antimicrobial activity against staphylococcus aureus. the diver ... | 1996 | 8880338 |
| nadp-specific glutamate dehydrogenase of penicillium chrysogenum has a homohexamer structure. | the nadp-specific glutamate dehydrogenase of a high beta-lactam producing industrial strain of penicillium chrysogenum was purified to homogeneity. the enzyme (m(r) = 339,000 +/- 34,000) was demonstrated to have a homohexamer quaternary structure with a subunit molecular mass of m(r) = 56,000 +/- 2000. the n-terminal sequence of the enzyme was also determined and was found to be highly homologous to other fungal nadp-specific glutamate dehydrogenase sequences. | 1996 | 8914269 |
| localization of nucleolin binding sites on human and mouse pre-ribosomal rna. | nucleolin, a major rna binding protein of the nucleolus is found associated mainly to the pre-ribosomal particles and is absent from the cytoplasmic mature ribosomes. the role of this protein in ribosome biogenesis remains largely unknown, and is likely to be reflected by its rna binding properties. nucleolin contains in its central domain four rna recognition motifs (rrm, also called rbd for rna binding domain) which are conserved among different species. rna binding studies have revealed that ... | 1996 | 8915542 |
| identification, isolation and sequence of the aspergillus nidulans xlnc gene encoding the 34-kda xylanase. | the xlnc gene encoding the 34-kda xylanase (x34) of aspergillus nidulans (an) has been cloned and sequenced, as has its corresponding cdna. xlnc contains nine introns and shows considerable similarity to the xyna and xylp xylanase-encoding genes of a. kawachii (ak) and penicillium chrysogenum (pc), respectively. analysis of xylanase production in an multicopy transformants showed elevated levels of x34 and increased total xylanase activity, but no elevated production of other xylanases. northern ... | 1996 | 8917072 |
| phenoxymethylpenicillin amidohydrolases from penicillium chrysogenum. | a phenoxymethylpenicillin amidohydrolase which hydrolyses phenoxymethylpenicillin to 6-aminopenicillanic acid (6-apa) has been isolated from two species of penicillium chrysogenum. the amidohydrolase had a molecular mass of approx. 42 kda. its activity with benzylpenicillin as substrate was only 1.5% of that with phenoxymethylpenicillin and it was inhibited by its products. no penicillin formation from 6-apa and phenoxyacetyl or phenylacetyl coenzyme a was observed. the enzyme is thus distinct f ... | 1996 | 8925921 |
| factors affecting dna-binding proteins and pcbc transcript levels in penicillium chrysogenum. | proteins extracted from penicillium chrysogenum grown in either complex or defined medium were used in electromobility shift assays. with a probe dna covering the region -10 to -132 relative to the pcbc translation start codon, four protein/dna complexes (designated a-d) were reproducibly observed. two of the four dna/protein complexes routinely detected in extracts from liquid cultures (a and b) were also detectable with protein extracts from p. chrysogenum spores. generally, with proteins from ... | 1996 | 8929398 |
| cloning and characterization of chitin synthase gene fragments from penicillium chrysogenum. | dna fragments homologous to chitin synthase were amplified from the genomic dna of penicillium chrysogenum by pcr. cloning and sequencing of the pcr-amplified fragments led to the identification of four different genes, designated pcchs1, pcchs2, pcchs3, and pcchs4. by comparison of the deduced amino acid sequences, pcchs1 was identified as a gene for class i chitin synthase, pcchs2 and pcchs3 were for class ii, and pcchs4 was for class iii. among these only pcchs4 includes an intervening sequen ... | 1996 | 8931329 |
| sequence analysis and expression of the penicillium chrysogenum nitrate reductase encoding gene (niad). | the nitrate reductase gene (niad) of the filamentous fungus penicillium chrysogenum encodes a protein of 864 amino acids. the derived protein sequence shows 78% and 72% sequence identity to the corresponding aspergillus niger and a. nidulans proteins, respectively. the coding region of the penicillium gene is interrupted by six small introns, as deduced by comparison with the niad sequences of a. niger and a. nidulans, whereby the positions of the introns are perfectly conserved between these th ... | 1996 | 8950182 |
| purification and characterization of an extracellular alkaline phosphatase from penicillium chrysogenum. | an extracellular alkaline phosphatase from penicillium chrysogenum was purified to homogeneity using deae ion-exchange chromatography and size exclusion chromatography. sds-page of the purified enzyme indicated a molecular weight of 58,000. the mobility of the native enzyme on a superose 12 column suggests that the active form of the enzyme is a monomer. the enzyme catalyzes the hydrolysis of phosphate from a variety of substrates including p-nitrophenyl phosphate, alpha-naphthyl phosphate and t ... | 1996 | 8958566 |
| specificity of a sandwich enzyme-linked immunosorbent assay for detecting aspergillus galactomannan. | the specificity of a sandwich enzyme-linked immunosorbent assay (elisa) for detecting aspergillus galactomannan was tested with exoantigens of 29 fungi cultured from clinical specimens. cross-reactivity was observed with penicillium chrysogenum, penicillium digitatum, and paecilomyces variotii. furthermore, 40 serum samples obtained from bacteremic patients with hematologic malignancies were retrospectively tested by sandwich elisa. false-positive reactions with the serum were reproducible but d ... | 1997 | 8968919 |
| molecular cloning and expression in different microbes of the dna encoding pseudomonas putida u phenylacetyl-coa ligase. use of this gene to improve the rate of benzylpenicillin biosynthesis in penicillium chrysogenum. | the gene encoding phenylacetyl-coa ligase (pcl), the first enzyme of the pathway involved in the aerobic catabolism of phenylacetic acid in pseudomonas putida u, has been cloned, sequenced, and expressed in two different microbes. in both, the primary structure of the protein was studied, and after genetic manipulation, different recombinant proteins were analyzed. the pcl gene, which was isolated from p. putida u by mutagenesis with the transposon tn5, encodes a 48-kda protein corresponding to ... | 1996 | 8969218 |
| the inhibitory mechanisms of glucose and carbon dioxide on the biosyntheses of penicillins and cephalosporins. | the inhibitory mechanism of glucose and co2 on the biosyntheses of penicillins and cephalosporins is discussed in the present paper. 6-aminopenicillanic acid (6-apa) is considered to be an intermediate product, and the reaction between 6-apa and glucose may play an important role in the yield and rate of biosyntheses of beta-lactam antibiotics. according to this hypothesis the experimental phenomena taking place in biosynthesis of penicillin and cephalosporin, such as the inhibition by glucose a ... | 1996 | 8987882 |
| molecular analysis of a penicillium chrysogenum gata factor encoding gene (srep) exhibiting significant homology to the ustilago maydis urbs1 gene. | employing a pcr-aided strategy, a penicillium chrysogenum gene (srep) encoding a putative gata-transcription factor has been cloned and characterized. comparison of the genomic and cdna sequences revealed the presence of an open reading frame (orf) encoding a protein of 532 amino acids (aa) which is interrupted by two introns. the deduced aa sequence of srep reveals 50% identity to a regulator of siderophore biosynthesis (urbs1) from ustilago maydis over a stretch of 200 aa containing two gata-t ... | 1997 | 9016950 |
| regulated system for heterologous gene expression in penicillium chrysogenum. | a system for regulated heterologous gene expression in the filamentous fungus penicillium chrysogenum was established. this is the first heterologous expression system to be developed for this organism. expression of a recombinant fungal xylanase gene (xylp) and the cdna for the human tear lipocalin (lcni) was achieved by placing the encoding sequences under the control of the repressible acid phosphatase gene (phoa) promoter of p. chrysogenum. secreted recombinant proteins were detected in the ... | 1997 | 9023952 |
| molecular regulation of penicillin biosynthesis in aspergillus (emericella) nidulans. | the beta-lactam antibiotic penicillin is produced as end product by only some filamentous fungi, most notably by aspergillus nidulans and penicillium chrysogenum. the biosynthesis of this secondary metabolite is catalyzed by three enzymes which are encoded by the following three genes: acva (pcbab), ipna (pcbc) and aat (pende). the genes are organized into a gene cluster. in a. nidulans, several studies have indicated that the genes are controlled by a complex regulatory network. the wide-domain ... | 1997 | 9066103 |
| effect of water activity, modified atmosphere packaging and storage temperature on spore germination of moulds isolated from prunes. | the combined effect of medium water activity (aw) modified atmosphere packaging (map) on the conidial germination of aspergillus niger, eurotium amstelodami, penicillium chrysogenum and fusarium oxysporum was studied by applying response surface methodology (rsm) for 45 days incubation at 20, 30 and 40 degrees c. oxytetracycline glucose yeast extract (ogye) agar media were prepared over a wide range of aw (0.80-0.95), controlled by glucose. the headspace atmosphere composition varied from 0-20% ... | 1997 | 9081224 |
| are fungi-specific ige found in staff suffering from nonallergic sick building syndrome? | 1997 | 9098775 | |
| extracellular ph affects regulation of the pcbab gene in penicillium chrysogenum. | the effect of extracellular ph and dissolved oxygen on regulation of the pcbab gene in p. chrysogenum was examined, using northern analysis and a reporter gene fusion. it was found that ambient ph markedly affected levels of pcbab mrna whereas maintenance of dissolved oxygen concentration above 10% had no detectable effect. the presence of a dna-binding protein, which binds upstream of the pcbab translational start codon, was also related to ambient ph. in all fermentations, pcbab mrna was most ... | 1997 | 9114516 |
| growth energetics and metabolic fluxes in continuous cultures of penicillium chrysogenum. | continuous cultures of the penicillin producing fungus penicillium chrysogenum have been analyzed with respect to the macromolecular composition of the mycelium. all cultivations were carried out using a chemically defined medium with glucose as the growth limiting component. biomass was harvested at steady state and analyzed for proteins, lipids, rna, dna, and carbohydrates. carbohydrates present in the cell wall, i.e., glucans and chitin, and carbohydrates serving as storage materials, i.e., g ... | 1996 | 9147448 |
| genetic analysis of regulatory mutants affecting synthesis of extracellular proteinases in the yeast yarrowia lipolytica: identification of a rim101/pacc homolog. | depending on the ph of the growth medium, the yeast yarrowia lipolytica secretes both an acidic proteinase and an alkaline proteinase, the synthesis of which is also controlled by carbon, nitrogen, and sulfur availability, as well as by the presence of extracellular proteins. recessive mutations at four unlinked loci, named pal1 to pal4, were isolated which prevent alkaline proteinase derepression under conditions of carbon and nitrogen limitation at ph 6.8. these mutations markedly affect matin ... | 1997 | 9199331 |
| fungal allergens from important allergenic fungi imperfecti. | occurrence of several fungal species in the environment seems to be related to hypersensitivity disorders in humans. fungal allergen studies reported in the literature are reviewed regarding to aspergillus, alternaria, penicillium and cladosporium genera. in this paper, we study by means of in vivo (skin prick test) and in vitro (rast and immunoblotting) the classical question of the best source of allergenic material using a population of asthmatic patients sensitized to different mould genera. ... | 1997 | 9208052 |
| fungi associated with post-harvest rot of black plum (vitex doniana) in nigeria. | the fungi associated with rot of vitex doniana fruits (blackplum) were isolated and identified. aspergillus niger, botryodiplodia theobromae, candida spp. penicillium chrysogenum, rhizopus stolonifer, fusarium pallidoroseum f. oxysporum and mucor mucedo were the primary rot causing fungi in contrast to cladosporium herbarum and mucor circinelloides which were just present as secondary colonizers. the rot fungi penetrated mainly through wounds and bruises on the surface of fruits. mature green fr ... | 1996 | 9208478 |
| purification and some properties of a novel dsrna degrading nuclease bound to rye germ ribosomes. | a two-step procedure including affinity chromatography for purification of rye germ ribosomal nuclease that degrades double-stranded rna from a virus of penicillium chrysogenum and the poly(i).poly(c) complex was developed. the specific activity towards poly(i).poly(c) of the obtained nuclease preparations was 30 times as high as that of ribosomes. the recovery of activity was 3.4% when the octyl-sepharose column was used, and 2.0% in the case of the phenyl-sepharose column. on polyacrylamide/sd ... | 1997 | 9241355 |
| monoclonal antibodies as probes for fungal wall structure during morphogenesis. | three monoclonal antibodies (mabs), s4d1, s3b3 and s1e5, were produced from hybridoma cell lines raised from mice immunized with hyphal walls of neurospora crassa and one (pax-1) from mice immunized with hyphal walls of paxillus involutus. in immunofluorescence studies, the three n. crassa mabs recognized epitopes with different patterns of distribution at the hyphal surface of n. crassa. s4d1 recognized an epitope which was present on the surface of both conidia and hyphae; s3b3 recognized an e ... | 1997 | 9245814 |
| multianalyte biosensors on optical imaging bundles. | we present an optical biosensor design that expands the utility of enzyme biosensors. these biosensors are fabricated by site-selective photodeposition of analyte-sensitive polymer matrices on optical imaging fibres. these dual-analyte arrays allow for the simultaneous, independent measurement of the analyte of interest and the transducing analyte. the first integrated optical-biosensors using this design have been prepared that allow both the dependent and independent analytes to be measured si ... | 1997 | 9253155 |
| phenoxyacetic acid induces glutathione-dependent detoxification and depletes the glutathione pool in penicillium chrysogenum. | enzymes of the glutathione-dependent detoxification pathway (glutathione s-transferase and gamma-glutamyl-transpeptidase) were induced, and the glutathione pool was completely depleted by phenoxyacetic acid in penicillium chrysogenum mycelia incubated for 15 h in a culture medium containing lactose as a carbon source and sodium glutamate as a nitrogen source. a significant increase in both the oxidised glutathione concentrations and the glutathione reductase activities were also observed. 1-chlo ... | 1997 | 9265740 |
| acv synthetase: expression of amino acid activating domains of the penicillium chrysogenum enzyme in aspergillus nidulans. | fragments of acv synthetase of penicillium chrysogenum carrying partial activities of amino acid activation were expressed under the alca promoter in an acva-deletion mutant of aspergillus nidulans. the 210 kda domain a-beta-galactosidase fusion protein was partially cleaved to fragments of 200 and 97 kda. the domain a fragment and the 312 kda domain bc construct were identified by peptide specific antibodies and shown to catalyze alpha-aminoadipate-, cysteine-, and valine-dependent atp/[32p]ppi ... | 1997 | 9266851 |
| overexpression of nreb, a new gata factor-encoding gene of penicillium chrysogenum, leads to repression of the nitrate assimilatory gene cluster. | to investigate the mechanism of nitrogen metabolite repression in the biotechnologically important fungus penicillium chrysogenum a polymerase chain reaction approach was employed to identify transcription factors involved in this regulatory circuit, leading to the isolation of a new gene (nreb) encoding a 298 amino acid protein. despite a low overall amino acid sequence identity of approximately 30%, it shares several features with dal80p/uga43p and gzf3p/nil2p, both repressors in nitrogen meta ... | 1997 | 9278412 |
| analysis of a commercially improved penicillium chrysogenum strain series: involvement of recombinogenic regions in amplification and deletion of the penicillin biosynthesis gene cluster. | several commercially improved strains of penicillium chrysogenum have been shown to carry amplifications of the entire penicillin biosynthesis gene cluster. analysis previously carried out using the strain bw 1890 has here been extended to the characterisation of other members of the smithkline beecham strain improvement series. we have determined the length of the amplicon to be 57.4 kb and shown a general increase in copy number and penicillin titre through the series. sequence analyses of the ... | 1997 | 9281849 |
| mould-devouring mites differ in guanine excretion from dust-eating acari, a possible error source in mite allergen exposure studies. | measurement of guanine in dust proved a good assessment of mite allergen exposure. | 1997 | 9291290 |
| glutathione metabolism and protection against oxidative stress caused by peroxides in penicillium chrysogenum. | the filamentous fungus penicillium chrysogenum showed remarkable resistance to the oxidative stress caused by high concentrations of either hydrogen peroxide (0.35-0.70 m) or tert-butyl hydroperoxide (tert-booh, 0.5-2.0 mm), which could be explained well with high levels of glutathione (gsh) peroxidase and catalase activities. the majority of exogenous h2o2 was likely removed by catalase from the cells while tert-booh was likely eliminated mainly by the gsh-dependent pathways. the gsh pool decre ... | 1997 | 9296459 |