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molecular characterization of a fungal gene paralogue of the penicillin pende gene of penicillium chrysogenum.penicillium chrysogenum converts isopenicillin n (ipn) into hydrophobic penicillins by means of the peroxisomal ipn acyltransferase (iat), which is encoded by the pende gene. in silico analysis of the p. chrysogenum genome revealed the presence of a gene, pc13g09140, initially described as paralogue of the iat-encoding pende gene. we have termed this gene ial because it encodes a protein with high similarity to iat (ial for iat-like). we have conducted an investigation to characterize the ial ge ...200919470155
indoor fungal contamination of moisture-damaged and allergic patient housing analysed using real-time pcr.the aim of our study was to compare, using real-time (rt) pcr, quantitative levels of five fungal species in three kinds of dwellings.200919486284
quantitative pcr study on the mode of action of oligosaccharide elicitors on penicillin g production by penicillium chrysogenum.to investigate the effects of single and multiple additions of the oligosaccharide elicitors, obtained from alginate and locust bean gum, on penicillin g production and the transcript level of penicillin g biosynthetic genes.200919486407
application of raisin extracts as preservatives in liquid bread and bread systems.interest in natural ingredients with multifunctions in food has led to the investigation of the antimicrobial activity of raisins, a traditional baking ingredient. water and 60% ethanol extracts, and raisin juice concentrate (rjc, a commercial food ingredient) were assessed for their ability to inhibit the growth of ropy-bread-causing bacillus species. the ability of these additives and raisin paste were tested for antifungal activity in liquid bread model system and bread. in the liquid bread m ...200919490336
the global regulator laea controls penicillin biosynthesis, pigmentation and sporulation, but not roquefortine c synthesis in penicillium chrysogenum.the biosynthesis of the beta-lactam antibiotic penicillin is an excellent model for the study of secondary metabolites produced by filamentous fungi due to the good background knowledge on the biochemistry and molecular genetics of the beta-lactam producing microorganisms. the three genes (pcbab, pcbc, pende) encoding enzymes of the penicillin pathway in penicillium chrysogenum are clustered, but no penicillin pathway-specific regulators have been found in the genome region that contains the pen ...200918952140
isolation and characterisation of polychlorinated biphenyl (pcb) degrading fungi from a historically contaminated soil.abstract:200919138404
aspergillus fumigatus germ tube growth and not conidia ingestion induces expression of inflammatory mediator genes in the human lung epithelial cell line a549.inhalation of conidia is the main cause of invasive pulmonary aspergillosis (ipa) and the respiratory epithelium is the first line of defence. to explore the triggering factor for the inflammatory response to aspergillus fumigatus, the species mainly responsible for ipa, this study analysed the differential expression of three inflammatory genes in a549 cells after challenge with live and killed conidia. the influence of steroids, one of the main risk factors for developing ipa, was also investi ...200919141733
contribution of peroxisomes to penicillin biosynthesis in aspergillus nidulans.peroxisomal localization of the third enzyme of the penicillin biosynthesis pathway of aspergillus nidulans, acyl-coenzyme a:ipn acyltransferase (iat), is mediated by its atypical peroxisomal targeting signal 1 (pts1). however, mislocalization of iat by deletion of either its pts1 or of genes encoding proteins involved in peroxisome formation or transport does not completely abolish penicillin biosynthesis. this is in contrast to the effects of iat mislocalization in penicillium chrysogenum.200919151327
matching the proteome to the genome: the microbody of penicillin-producing penicillium chrysogenum cells.in the filamentous fungus penicillium chrysogenum, microbodies are essential for penicillin biosynthesis. to better understand the role of these organelles in antibiotics production, we determined the matrix enzyme contents of p. chrysogenum microbodies. using a novel in silico approach, we first obtained a catalogue of 200 p. chrysogenum proteins with putative microbody targeting signals (ptss). this included two orthologs of proteins involved in cephalosporin biosynthesis, which we demonstrate ...200919156454
synthesis of sulfated glucosaminides for profiling substrate specificities of sulfatases and fungal beta-n-acetylhexosaminidases.systematic sulfation: sulfated glycoconjugates are degraded either by desulfation followed by glycoside cleavage, or by glycoside cleavage followed by desulfation. to study these processes, here we report the synthesis of four regioisomerically sulfated p-nitrophenyl glucosaminides from the common precursor p-nitrophenyl n-acetyl-beta-d-glucosaminide. these substrates allowed the rapid analysis of the substrate preferences of a set of four sulfatases and 24 hexosaminidases.sulfated carbohydrates ...200919156788
the vacuolar serine protease, a cross-reactive allergen from cladosporium herbarum.subtilisin-like serine proteases make up one of the most important allergen-families regarding the number of individual allergens. previously, fungal subtilisin-like serine proteases have been identified from aspergillus-, penicillium-, and trichophyton-species having a prevalence of ige-reactivity between 33% and 80%. since ige-cross-reactivity is a common phenomenon within fungal species we wanted to know whether this protein also represents an allergen in cladosporium herbarum. hence, a scree ...200919162325
disruption of the nadph-dependent glutamate dehydrogenase affects the morphology of two industrial strains of penicillium chrysogenum.new morphological aspects of penicillium chrysogenum were found during physiological characterisation of two nadph-dependent glutamate dehydrogenase mutant strains. a morphological characterisation of the previously constructed strains, together with the two beta-lactam producing industrial recipient strains, was conducted. the reference strains showed a compact structure with highly branched hyphal elements whereas the morphology of the deltagdha strains consisting of long elongated hyphal elem ...200919167440
exploring and dissecting genome-wide gene expression responses of penicillium chrysogenum to phenylacetic acid consumption and penicilling production.since the discovery of the antibacterial activity of penicillin by fleming 80 years ago, improvements of penicillin titer were essentially achieved by classical strain improvement through mutagenesis and screening. the recent sequencing of penicillium chrysogenum strain wisconsin1255-54 and the availability of genomics tools such as dna-microarray offer new perspective.200919203396
cultivated anti-aspergillus t(h)1 cells.invasive aspergillosis remains a serious complication in patients undergoing allogeneic stem cell transplantation. since it became clear that lymphocytes provide a critical secondary defense against fungi, adoptive transfer of functionally active anti-aspergillus t cells might be an option to restore adaptive immune effector mechanisms. using the interferon (ifn)-gamma secretion assay, we isolated human activated t cells upon stimulation with a cellular extract of aspergillus fumigatus. after a ...200918651313
characterization of a phenylacetate-coa ligase from penicillium chrysogenum.enzymatic activation of paa (phenylacetic acid) to phenylacetyl-coa is an important step in the biosynthesis of the beta-lactam antibiotic penicillin g by the fungus penicillium chrysogenum. coa esters of paa and poa (phenoxyacetic acid) act as acyl donors in the exchange of the aminoadipyl side chain of isopenicillin n to produce penicillin g or penicillin v. the phl gene, encoding a pcl (phenylacetate-coa ligase), was cloned in escherichia coli as a maltose-binding protein fusion and the bioch ...200918834333
[analysis of oxygen transfer in bioreactors for fungus broths. 2. suspensions of p. chrysogenum mycelial associations].unlike the p. shermanii and s. cerevisiae cultures, the study on the distribution of oxygen transfer in stirred bioreactor for p. chrysogenum pellets broths indicated that this process is controlled mainly by the deposition tendency of the biomass. similar to the previously studied systems, the analysis of k(1)a distribution indicated its heterogeneity on the bioreactor height, the oxygen transfer rate increasing from position 1 to 4. contrary to the bacterial and yeasts cultures, the intensific ...200920191858
[effects of pa-pex 11 gene on penicillin production in penicillium aurantiogriseum].to study the effect of pa-pex 11 gene on penicillin production in pencillium aurantiogriseum.200920112676
an engineered yeast efficiently secreting penicillin.this study aimed at developing an alternative host for the production of penicillin (pen). as yet, the industrial production of this beta-lactam antibiotic is confined to the filamentous fungus penicillium chrysogenum. as such, the yeast hansenula polymorpha, a recognized producer of pharmaceuticals, represents an attractive alternative. introduction of the p. chrysogenum gene encoding the non-ribosomal peptide synthetase (nrps) delta-(l-alpha-aminoadipyl)-l-cysteinyl-d-valine synthetase (acvs) ...200920016817
proteolytic activity of beef luncheon fungi as affected by incorporation of some food preservatives.screening of thirty-one fungal isolates (representing 16 genera, 28 species and 3 varieties) collected from beef luncheon meat for their abilities to produce protease enzyme revealed that eleven isolates (35.48%) exhibited high protease production. however, fifteen isolates (48.39%) had moderate ability and 5 isolates (16.13%) were low producers. aspergillus flavus, gibberella fujikuroi and penicillium chrysogenum were the most active producers of protease. the incorporation of five chemical sub ...200920038493
indoor mold concentration in eastern france.our prospective case-control study of 118 dwellings in eastern france examined fungal contamination in unhealthy dwellings (n = 32) (homes with visible mold contamination and adverse health outcomes reported by the occupants), dwellings occupied by allergic patients (with medical diagnostic and positive prick-tests for molds) (n = 27) and matched control dwellings (n = 59). unhealthy dwellings present higher airborne concentrations of aspergillus, penicillium, and cladosporium than control dwell ...200919840143
molds, mycotoxins, and sick building syndrome.the following is a review of some of the work we have done since 2004 regarding the importance of molds and their mycotoxins in the phenomenon of sick building syndrome (sbs). in these studies we showed that the macrocyclic trichothecene mycotoxins (mtm) of stachybotrys chartarum (sc) are easily dissociated from the surface of the organism as it grows and could therefore be consequently spread in buildings as the fungus experiences additional water events. we then showed that sc and penicillium ...200919854820
fungal spores: a critical review of the toxicological and epidemiological evidence as a basis for occupational exposure limit setting.fungal spores are ubiquitous in the environment. however, exposure levels in workplaces where mouldy materials are handled are much higher than in common indoor and outdoor environments. spores of all tested species induced inflammation in experimental studies. the response to mycotoxin-producing and pathogenic species was much stronger. in animal studies, nonallergic responses dominated after a single dose. allergic responses also occurred, especially to mycotoxin-producing and pathogenic speci ...200919863384
aspects on evolution of fungal beta-lactam biosynthesis gene clusters and recruitment of trans-acting factors.penicillins and cephalosporins are beta-lactam antibiotics. the formation of hydrophobic penicillins has been reported in fungi only, notably penicillium chrysogenum and aspergillus (emericella) nidulans, whereas the hydrophilic cephalosporins are produced by both fungi, e.g., acremonium chrysogenum (cephalosporin c), and bacteria. the producing bacteria include gram-negatives and gram-positives, e.g., streptomyces clavuligerus (cephamycin c) and lysobacter lactamgenus (cephabacins), respectivel ...200919863978
heterologous production of non-ribosomal peptide lld-acv in saccharomyces cerevisiae.non-ribosomal peptides (nrps) are a diverse family of secondary metabolites with a broad range of biological activities. we started to develop an eukaryotic microbial platform based on the yeast saccharomyces cerevisiae for heterologous production of nrps using delta-(l-alpha-aminoadipyl)-l-cysteinyl-d-valine (acv) as a model nrp. the penicillium chrysogenum gene pcbab encoding acv synthetase was expressed in s. cerevisiae from a high-copy plasmid together with phosphopantetheinyl transferase (p ...200919686863
comparison of skin prick tests with specific serum immunoglobulin e in the diagnosis of fungal sensitization in patients with severe asthma.it has been shown that patients with allergic bronchopulmonary aspergillosis (abpa) and patients with severe asthma with fungal sensitization (safs) can benefit from antifungal therapy. it is not known whether allergy skin prick tests (spt) or specific ige tests are more sensitive in the identification of patients who are sensitized to fungi and who are therefore candidates for antifungal therapy.200919689458
an efficient method for 15n-labeling of chitin in fungi.to permit facile (15)n solid-state nmr (ssnmr) analysis of the degree of acetylation (da) of chitinous materials in fungi a method for the introduction of a (15)n isotopic label has been developed. using penicillium chrysogenum as a model system, a series of (15)n-based media were surveyed for their abilities to support mycelial growth, and a rich medium supplemented with ((15)nh(4))(2)so(4) supported good growth. uptake of label into chitin extracted from mycelia grown in the rich ((15)nh(4))(2 ...200919249848
simultaneous quantification of free nucleotides in complex biological samples using ion pair reversed phase liquid chromatography isotope dilution tandem mass spectrometry.a new sensitive and accurate analytical method has been developed for quantification of intracellular nucleotides in complex biological samples from cultured cells of different microorganisms such as saccharomyces cerevisiae, escherichia coli, and penicillium chrysogenum. this method is based on ion pair reversed phase liquid chromatography electrospray ionization isotope dilution tandem mass spectrometry (ip-lc-esi-id-ms/ms. a good separation and low detection limits were observed for these com ...200919250917
transcriptional upregulation of four genes of the lysine biosynthetic pathway by homocitrate accumulation in penicillium chrysogenum: homocitrate as a sensor of lysine-pathway distress.the lysine biosynthetic pathway has to supply large amounts of alpha-aminoadipic acid for penicillin biosynthesis in penicillium chrysogenum. in this study, we have characterized the p. chrysogenum l2 mutant, a lysine auxotroph that shows highly increased expression of several lysine biosynthesis genes (lys1, lys2, lys3, lys7). the l2 mutant was found to be deficient in homoaconitase activity since it was complemented by the aspergillus nidulans lysf gene. we have cloned a gene (named lys3) that ...200919696106
chapter 5: zones of inhibition? the transfer of information relating to penicillin in europe during world war ii.alexander fleming published his first description of penicillin in 1929, but the journal articles that were to propel penicillin from its relative obscurity were those of howard florey and his co-workers at oxford university. these were published in the lancet in the early years of world war ii and although wartime conditions restricted the flow of information on penicillin throughout europe, they never succeeded in shutting it off altogether. in germany an information-gathering initiative was e ...200919729093
preparation of fungal conidia impacts their susceptibility to inactivation by ethanol vapours.a common protocol employed for the preparation of conidia employs flooding a fungal colony grown on semi-solid media under optimum conditions with an aqueous solution. in contrast, conidia produced in a natural environment are usually not hydrated when disseminated in air and can be produced under water stress. in order to simulate the latter conditions, cultures were grown at different water activities and conidia were dry-harvested on the lid by turning the dishes upside-down then gently tappi ...200919762103
structure of the two-domain hexameric aps kinase from thiobacillus denitrificans: structural basis for the absence of atp sulfurylase activity.the tbd_0210 gene of the chemolithotrophic bacterium thiobacillus denitrificans is annotated to encode a 60.5 kda bifunctional enzyme with atp sulfurylase and aps kinase activity. this putative bifunctional enzyme was cloned, expressed and structurally characterized. the 2.95 a resolution x-ray crystal structure reported here revealed a hexameric assembly with d(3) symmetry. each subunit contains a large n-terminal sulfurylase-like domain and a c-terminal aps kinase domain reminiscent of the two ...200919770499
effect of a heterotrimeric g protein alpha subunit on conidia germination, stress response, and roquefortine c production in penicillium roqueforti.heterotrimeric g protein signaling regulates many processes in fungi, such as development, pathogenicity, and secondary metabolite biosynthesis. for example, the galpha subunit pga1 from penicillium chrysogenum regulates conidiation and secondary metabolite production in this fungus. the dominant activating allele, pga1g42r, encoding a constitutively active pga1 galpha subunit, was introduced in penicillium roqueforti by transformation, resulting in a phenotype characterized by low sporulation a ...200919784932
evidence for dicer-dependent rna interference in the industrial penicillin producer penicillium chrysogenum.rna interference (rnai) is a sequence-specific post-transcriptional gene silencing system that downregulates target gene expression. here, we provide several lines of evidence for rna silencing in the industrial beta-lactam antibiotic producer penicillium chrysogenum using the dsred reporter gene under the control of the constitutive trpc promoter or the inducible xylp promoter. the functional rnai system was verified by detection of sirnas that hybridized exclusively with gene-specific (32)p-la ...200919797363
jem spotlight: fungi, mycotoxins and microbial volatile organic compounds in mouldy interiors from water-damaged buildings.concerns have been raised about exposure to mycotoxin producing fungi and the microbial volatile organic compounds (mvocs) they produce in indoor environments. therefore, the presence of fungi and mycotoxins was investigated in 99 samples (air, dust, wallpaper, mycelium or silicone) collected in the mouldy interiors of seven water-damaged buildings. in addition, volatile organic compounds (vocs) were sampled. the mycotoxins were analysed by liquid chromatography-tandem mass spectrometry (lc-ms/m ...200919809708
study on the diversity of endophytic communities from rice (oryza sativa l.) and their antagonistic activities in vitro.endophytic populations were isolated from 2400 segments of oryza sativa collected from bhadra river project area, southern india during december 2005 (winter) and april 2006 (summer). overall colonization rates from surface sterilized tissues were 40.3% in roots and 25.83% in leaves during winter season, 20.15% in roots and 8.66% in leaves during summer season. nineteen different fungal taxa, a streptomyces sp. and bacterial species were isolated. streptomyces sp., chaetomium globosum, penicilli ...200917433644
a metabolome study of the steady-state relation between central metabolism, amino acid biosynthesis and penicillin production in penicillium chrysogenum.the relation between central metabolism and the penicillin biosynthesis pathway in penicillium chrysogenum was studied by manipulating the steady-state flux in both pathways. a high producing industrial strain was cultivated at a growth rate mu=0.05 h(-1) in glucose-limited chemostat cultures, both under penicillin-g producing and non-producing conditions. non-producing conditions were accomplished in two ways: (1) by cultivation without addition of the side chain precursor phenylacetic acid and ...200817905623
minimization of a eukaryotic mini-intein.inteins are internal protein splicing elements that can autocatalytically self-excise from their host protein and ligate the protein flanks (exteins) with a peptide bond. large inteins comprise independent protein splicing and endonuclease domains whereas mini-inteins lack the central endonuclease domain. to identify mini-intein domains that are essential for protein splicing, deletions were introduced at different sites of the 157-aa prp8 mini-intein of penicillium chrysogenum. the removal of e ...200818054328
fungistatic activity of flaxseed in potato dextrose agar and a fresh noodle system.although numerous researchers have studied flaxseed as a food ingredient for its health benefits, flaxseed (linum usitatissimum) has never been considered as a food preservative. the objective of this study was to investigate the effect of flaxseed flour (ff) concentration (0, 6, 9, 12, and 15% wt/wt), cultivar ('omega' and brown) and source (four seed companies located in minnesota and north dakota) on flaxseed fungistatic activity. fungal radial growth was used to assess the fungistatic activi ...200818077042
the penicillium chrysogenum antifungal protein paf, a promising tool for the development of new antifungal therapies and fungal cell biology studies.in recent years the interest in antimicrobial proteins and peptides and their mode of action has been rapidly increasing due to their potential to prevent and combat microbial infections in all areas of life. a detailed knowledge about the function of such proteins is the most important requirement to consider them for future application. our research in recent years has been focused on the low molecular weight, cysteine-rich and cationic antifungal protein paf from penicillium chrysogenum, whic ...200817965829
fungal growth inhibitory properties of new phytosphingolipid analogues.to study the growth inhibitory properties of a series of phytosphingosine (phs) and phytoceramide (phc) analogues.200818005346
inactivation of conidia of penicillium chrysogenum, p. digitatum and p. italicum by ethanol solutions and vapours.a fractional factorial design, 2(5-1) experiments, was used for assessing the influence of 5 factors: water activity, aw [0.7, 0.9], temperature, t ( degrees c) [10, 30], mode of application, a [liquid, vapour], ethanol concentration, e (% w/w) [5, 10] and time, t (d) [1, 4] on the inactivation of spores of penicillium chrysogenum, p. digitatum and p. italicum. survival was determined by germination at optimal conditions within 3d. the experimental response was log (n 0/nt), where n 0 and nt (sp ...200818160164
antifungal activity stability of flaxseed protein extract using response surface methodology.the stability of the antifungal activity of flaxseed (linum usitatissimum) protein extract was evaluated in this study. response surface methodology (rsm) using box-behnken factorial design was used to evaluate the effects of treatment variables, that is, temperature (50 to 90 degrees c), time (1 to 29 min), and ph (2 to 8), on the residual antifungal activity (raa) against penicillium chrysogenum, fusarium graminearum, aspergillus flavus, and a penicillium sp. isolated from moldy noodles. regre ...200818211360
eighty years after its discovery, fleming's penicillium strain discloses the secret of its sex.eighty years ago, alexander fleming discovered antibacterial activity in the asexual mold penicillium, and the strain he studied later was replaced by an overproducing isolate still used for penicillin production today. using a heterologous pcr approach, we show that these strains are of opposite mating types and that both have retained transcriptionally expressed pheromone and pheromone receptor genes required for sexual reproduction. this discovery extends options for industrial strain improve ...200818223118
quantitative analysis of metabolites in complex biological samples using ion-pair reversed-phase liquid chromatography-isotope dilution tandem mass spectrometry.a rapid, sensitive and selective ion-pair reversed-phase liquid chromatography-electrospray ionization isotope dilution tandem mass spectrometry (ip-lc-esi-id-ms/ms) was developed for quantitative analysis of free intracellular metabolites in cell cultures. as an application a group of compounds involved in penicillin biosynthesis pathway of penicillium chrysogenum cells, such as penicillin g (peng), 6-aminopenicillanic acid (6-apa), benzylpenicilloic acid (pio), ortho-hydroxyphenyl acetic acid ...200818295225
repeat induced point mutation in two asexual fungi, aspergillus niger and penicillium chrysogenum.repeat induced point mutation (rip) is a gene silencing mechanism present in fungal genomes. during rip, duplicated sequences are efficiently and irreversibly mutated by transitions from c:g to t:a. for the first time, we have identified traces of rip in transposable elements of aspergillus niger and penicillium chrysogenum, two biotechnologically relevant fungi. we found that rip in p. chrysogenum has affected a large set of sequences, which also contain other mutations. on the other hand, rip ...200818347798
vacuolar serine protease is a major allergen of cladosporium cladosporioides.cladosporium is an important allergenic fungus worldwide. we report here a major allergen of c. cladosporioides.200818362473
heterotrimeric galpha protein pga1 of penicillium chrysogenum controls conidiation mainly by a camp-independent mechanism.fungal heterotrimeric g proteins regulate different processes related to development, such as colony growth and asexual sporulation, the main mechanism of propagation in filamentous fungi. to gain insight into the mechanisms controlling growth and differentiation in the industrial penicillin producer penicillioum chrysogenum, we investigated the role of the heterotrimeric galpha subunit pga1 in conidiogenesis. a pga1 deleted strain (deltapga1) and transformants with constitutively activated (pga ...200818364746
production of functionally active penicillium chrysogenum isopenicillin n synthase in the yeast hansenula polymorpha.beta-lactams like penicillin and cephalosporin are among the oldest known antibiotics used against bacterial infections. industrially, penicillin is produced by the filamentous fungus penicillium chrysogenum. our goal is to introduce the entire penicillin biosynthesis pathway into the methylotrophic yeast hansenula polymorpha. yeast species have the advantage of being versatile, easy to handle and cultivate, and possess superior fermentation properties relative to filamentous fungi. one of the f ...200818366686
nadph-dependent glutamate dehydrogenase in penicillium chrysogenum is involved in regulation of beta-lactam production.the interactions between the ammonium assimilatory pathways and beta-lactam production were investigated by disruption of the nadph-dependent glutamate dehydrogenase gene (gdha) in two industrial beta-lactam-producing strains of penicillium chrysogenum. the strains used were an adipoyl-7-adca- and a penicillin-producing strain. the gdha gene disruption caused a decrease in maximum specific growth rate of 26 % and 35 % for the adipoyl-7-adca-producing strain and the penicillin-producing strain, r ...200818375816
chrysogenamide a from an endophytic fungus associated with cistanche deserticola and its neuroprotective effect on sh-sy5y cells.chrysogenamide a (1), a new member of the macfortine group of alkaloids, along with four known compounds (2 approximately 5) were identified from penicillium chrysogenum no. 005, an endophytic fungus associated with cistanche deserticola y. c. ma. the new structure was elucidated on the basis of comprehensive spectral analysis. 1 exhibited a neurocyte protection effect against oxidative stress-induced cell death in sh-sy5y cells.200818408327
the unprocessed preprotein form iatc103s of the isopenicillin n acyltransferase is transported inside peroxisomes and regulates its self-processing.previous studies in penicillium chrysogenum and aspergillus nidulans suggested that self-processing of the isopenicillin n acyltransferase (iat) is an important differential factor in these fungi. expression of a mutant pende(c103s) gene in p. chrysogenum gave rise to an unprocessed inactive variant of iat (iat(c103s)) located inside peroxisomes, which indicates that transport of the proiat inside these organelles is not dependent on the processing state of the protein. co-expression of the pend ...200818439860
[investigation of the effect of constructions in hospital environment on the crucial units for immunocompromised patients and the development of opportunistic mold infections].this study was planned to determine the effect of building constructions in and around our hospital, on the development of opportunistic mold infections in immunocompromised patients hospitalized in bone marrow and kidney transplantation units and haematology and oncology units. samples were collected from high risk units by an air sampler (air ideal) from indoors and outdoors of a total of 43 patient rooms. the most commonly isolated species from indoor air cultures of our hospital were penicil ...200818444565
isotopic non-stationary 13c gluconate tracer method for accurate determination of the pentose phosphate pathway split-ratio in penicillium chrysogenum.current (13)c labeling experiments for metabolic flux analysis (mfa) are mostly limited by either the requirement of isotopic steady state or the extremely high computational effort due to the size and complexity of large metabolic networks. the presented novel approach circumvents these limitations by applying the isotopic non-stationary approach to a local metabolic network. the procedure is demonstrated in a study of the pentose phosphate pathway (ppp) split-ratio of penicillium chrysogenum i ...200818555197
post-translational enzyme modification by the phosphopantetheinyl transferase is required for lysine and penicillin biosynthesis but not for roquefortine or fatty acid formation in penicillium chrysogenum.nrpss (non-ribosomal peptide synthetases) and pkss (polyketide synthases) require post-translational phosphopantetheinylation to become active. this reaction is catalysed by a pptase (4'-phosphopantetheinyl transferase). the ppt gene of penicillium chrysogenum, encoding a protein that shares 50% similarity with the stand-alone large pptases, has been cloned. this gene is present as a single copy in the genome of the wild-type and high-penicillin-producing strains (containing multiple copies of t ...200818558918
phagocytosis of aspergillus fumigatus conidia by primary nasal epithelial cells in vitro.invasive aspergillosis, which is mainly caused by the fungus aspergillus fumigatus, is an increasing problem in immunocompromised patients. infection occurs by inhalation of airborne conidia, which are first encountered by airway epithelial cells. internalization of these conidia into the epithelial cells could serve as a portal of entry for this pathogenic fungus.200818564423
microbial and xanthine dehydrogenase inhibitory activity of some flavones.xanthine dehydrogenase (xdh) is responsible for the pathological condition called gout. in the present study different flavones synthesized from chalcone were evaluated in vitro for their inhibitory activity. inhibitory activity of flavones on xdh was determined in terms of inhibition of uric acid synthesis from xanthine. the enzymatic activity was found maximum at ph 7.5 and temperature 40 degrees c. the flavones 6-chloro-2-[3-(4-hydroxy-phenyl)-1-phenyl-1-h-pyrazol-4-yl]-chromen-4-one (f(1)) a ...200818569337
in vitro activity of penicillium chrysogenum antifungal protein (paf) and its combination with fluconazole against different dermatophytes.strains of five dermatophyte species (microsporum canis, microsporum gypseum, trichophyton mentagrophytes, trichophyton rubrum and trichophyton tonsurans) were selected for testing against penicillium chrysogenum antifungal protein (paf) and its combination with fluconazole (fcz). inhibition of microconidia germination and growth was detected with mics of paf ranging from 1.56 to 200 microg ml(-1) when it was used alone, or at constant concentration (100 microg ml(-1)) in combination with fcz at ...200818574706
occupational immunoglobulin e-mediated asthma due to penicillium camemberti in a dry-sausage packer.a 62-year-old female sausage packer reported progressive work-related asthma, rhinitis and contact urticaria after contact to dry sausages refined by moulds. whereas skin prick tests with commercial mould extracts were negative, the patient showed weak skin sensitization to a cultivated mould sample from a dry sausage. specific immunoglobulin e antibodies to various moulds were demonstrated by immunocap and antibodies to the cultivated mould sample were demonstrated by enzyme allergosorbent test ...200817108671
expression of the acremonium chrysogenum ceft gene in penicillum chrysogenum indicates that it encodes an hydrophilic beta-lactam transporter.the acremonium chryrsogenum ceft gene encoding a membrane protein of the major facilitator superfamily implicated in the cephalosporin biosynthesis in a. chrysogenum was introduced into penicillium chrysogenum wisconsin 54-1255 (a benzylpenicillin producer), p. chrysogenum npe6 pyrg(-) (a derivative of wisconsin 54-1255 lacking a functional pende gene) and p. chrysogenum ta98 (a deacetylcephalosporin producer containing the cefd1, cefd2, cefef and cefg genes from a. chrysogenum). rt-pcr analysis ...200818668246
expression of the transporter encoded by the ceft gene of acremonium chrysogenum increases cephalosporin production in penicillium chrysogenum.by introduction of the cefef genes of acremonium chrysogenum and the cmch gene of streptomyces clavuligerus, penicillium chrysogenum can be reprogrammed to form adipoyl-7-amino-3-carbamoyloxymethyl-3-cephem-4-carboxylic acid (ad7-accca), a carbamoylated derivate of adipoyl-7-aminodeacetoxy-cephalosporanic acid. the ceft gene of a. chrysogenum encodes a cephalosporin c transporter that belongs to the major facilitator superfamily. introduction of ceft into an ad7-accca-producing p. chrysogenum st ...200818691664
cloning and functional identification of c-4 methyl sterol oxidase genes from the penicillin-producing fungus penicillium chrysogenum.two c-4 methyl sterol oxidase genes (pcerg25a and pcerg25b) that are involved in ergosterol biosynthesis have been cloned from the penicillin-producing fungus penicillium chrysogenum. cdnas of both pcerg25a and pcerg25b have an orf 885 bp in length, encoding a peptide of 295 residues. the deduced amino acid sequences of pcerg25a and pcerg25b show 86% identity, and have high identities to the characterized c-4 methyl sterol oxidases from candida albicans and saccharomyces cerevisiae. the function ...200818707625
no-donors. part 17: synthesis and antimicrobial activity of novel ketoconazole-no-donor hybrid compounds.novel hybrid compounds combining the antifungal drug ketoconazole with a diazen-1-ium-1,2-diolate or an organic nitrate moiety and the corresponding no-donors without ketoconazole were synthesized and their activities against a broad variety of fungal strains were tested. hybridization modifies the spectrum of antimicrobial activities and generally, the ketoconazole-no-donor hybrids are more potent than ketoconazole. the no-donors alone show insufficient effectiveness.200818710813
antimicrobial effect of oxidized cellulose salts.antimicrobial properties of oxidized cellulose and its salts in linters (-l) and microsphere (-m) form (okcel h-l, okcel zn-m, okcel znna-l, okcel znna-m and okcel ag-l) were tested by a dilution method against a spectrum of microbial strains: escherichia coli, pseudomonas aeruginosa, staphylococcus epidermidis, bacillus licheniformis, aspergillus niger, penicillium chrysogenum, rhizopus oryzae, scopulariopsis brevicaulis, candida albicans and candida tropicalis. okcel ag-l exhibited antimicrobi ...200818712552
distributions of the growth rate of the germ tubes and germination time of penicillium chrysogenum conidia depend on water activity.the effects of water activities for sporulation (a(wsp)) and germination (a(wge)) on the distributions of the growth rate of the germ tubes (mu) and the germination time (t(g)) of penicillium chrysogenum conidia were determined by monitoring the length of the same germ tubes throughout the experiments automatically. no relationship between the individual t(g)'s and mu's could be established. irrespective of the water activity for germination, mu was greater and t(g) was less for conidia produced ...200818721680
lys89, lys90, and phe91 are critical core amino acid residues of the pen ch 18 major fungal allergen recognized by human ige antibodies.a vacuolar serine protease (pen ch 18) has been identified as a major allergen of penicillium chrysogenum. the molecular features of antigenic determinant(s) on pen ch 18 recognized by human ige antibodies, however, have remained unclear. here, we show that a dominant ige epitope on the n-terminally processed pen ch 18 allergen was narrowed down to residues 83-91. in addition, lys89, lys90, and possibly phe91 were identified as the core residues. substitution of lys89, lys90, or phe91 with alani ...200818760997
effect of the penicillium chrysogenum antifungal protein (paf) on barley powdery mildew and wheat leaf rust pathogens.the small molecular mass antifungal protein of penicillium chrysogenum (paf) inhibited the growths of two obligate biotrophic fungal pathogens, blumeria graminis f. sp. hordei and puccinia recondita f.sp. tritici and, hence, mitigated the symptoms of barley powdery mildew and wheat leaf rust infections, respectively. paf also affected adversely the germination of b. graminis conidia and p. recondita uredospores causing degenerative branching of germ tubes. since powdery mildews and rusts cause s ...200818798177
genome sequencing and analysis of the filamentous fungus penicillium chrysogenum.industrial penicillin production with the filamentous fungus penicillium chrysogenum is based on an unprecedented effort in microbial strain improvement. to gain more insight into penicillin synthesis, we sequenced the 32.19 mb genome of p. chrysogenum wisconsin54-1255 and identified numerous genes responsible for key steps in penicillin production. dna microarrays were used to compare the transcriptomes of the sequenced strain and a penicilling high-producing strain, grown in the presence and a ...200818820685
rna-silencing in penicillium chrysogenum and acremonium chrysogenum: validation studies using beta-lactam genes expression.in this work we report the development and validation of a new rna interference vector (pjl43-rnai) containing a double-stranded rna expression cassette for gene silencing in the filamentous fungi penicillium chrysogenum and acremonium chrysogenum. classical targeted gene disruption in these fungi is very laborious and inefficient due to the low frequency of homologous recombination. the rnai vector has been validated by testing the attenuation of two different genes of the beta-lactam pathway; ...200818590779
mold challenge study in bottled natural mineral waters and spring waters.microbiological challenge study was carried out to verify the microbial stability of bottled waters against four different mold species isolated from bottled water (fusarium sp.; cladosporium sp.; penicillium chrysogenum and aspergillus fumigatus) and to follow the growth of the molds in bottled water. twelve types of bottled water with different mineralization and co2 level in pet and glass packages were collected from 4 european countries. three different inoculation levels of spore suspension ...200818595319
mold species in dust from the international space station identified and quantified by mold-specific quantitative pcr.dust was collected over a period of several weeks in 2007 from hepa filters in the u.s. laboratory module of the international space station (iss). the dust was returned on the space shuttle atlantis, mixed, sieved and the dna was extracted. using a dna-based method called mold-specific quantitative pcr (msqpcr), 39 molds were measured in the dust. potential opportunistic pathogens aspergillus flavus and aspergillus niger and potential moderate toxin producers penicillium chrysogenum and penicil ...200818602989
fungistatic activity of heat-treated flaxseed determined by response surface methodology.the objective of this study was to evaluate the effect of heat treatment on the fungistatic activity of flaxseed (linum usitatissimum) in potato dextrose agar (pda) medium and a fresh noodle system. the radial growth of penicilliumn chrysogenum, aspergillus flavus, and a penicillium sp. isolated from moldy noodles, as well as the mold count of fresh noodle enriched with heat treated flaxseed, were used to assess antifungal activity. a central composite design in the response surface methodology ...200819241553
the heterotrimeric galpha protein pga1 regulates biosynthesis of penicillin, chrysogenin and roquefortine in penicillium chrysogenum.we have studied the role of the pga1 gene of penicillium chrysogenum, encoding the alpha subunit of a heterotrimeric g protein, in secondary metabolite production. the dominant activating pga1(g42r) mutation caused an increase in the production of the three secondary metabolites penicillin, the yellow pigment chrysogenin and the mycotoxin roquefortine, whereas the dominant inactivating pga1(g203r) allele and the deletion of the pga1 gene resulted in a decrease of the amount of produced penicilli ...200818957609
[preparation of a novel aminated fungal biomass and its sorption for typical endocrine disruptors].the fungal biomass of penicillium chrysogenum was used as raw materials to prepare the sorbent, and polyethylenimine (pei) was grafted onto the biomass surface in a two-step reaction. the best sorbent was obtained through the optimization experiments. as the pei-modified biomass was found to possess zero zeta-potential at ph 10.2, the biosorbent is favorable for the removal of anionic pentachlorophenol (pcp), 2,4-dichlorophenoxyacetic acid (2,4-d) and perfluorooctane sulphonate (pfos) potassium ...200818649533
ecological and physiological studies on soil fungi at western region, libya.sixty three species and 5 varieties belonging to 30 fungal genera were collected from 75 soil samples. cultivated (29 genera and 58 species + 5 var.), desert (22 and 35 + 2 var.) and saline soil (21 and 41 + 1 var.) fungi were recovered on glucose-, cellulose- and 50% sucrose-czapek's agar at 28℃. the most common genera were alternaria, aspergillus, emericella, fusarium, mycosphaerella, nectria and penicillium. the most prevalent species from the three types of soils on the three types of media ...200823997599
effect of some food preservatives on the lipolytic activity of beef luncheon fungi.beef luncheon meat is one of the most popular meals in several countries in the world including egypt. thirty one fungal species and 3 species varieties were recovered from 30 samples of beef luncheon meat collected from different supermarkets in qena. alternaria, aspergillus, emericella, mucor, mycosphaerella, penicillium and rhizopus were the most common genera on the two types of media. from the above genera, the most prevalent species were alternaria alternate, aspergillus flavus, a. fumigat ...200823997619
the pattern of sensitisation to inhalant allergens in omani patients with asthma, allergic rhinitis and rhinoconjunctivitis.identification of relevant allergens that are prevalent in each environment which may have diagnostic and therapeutic implications in allergic diseases. this study aimed to identify the pattern of sensitisation to inhalant allergens in omani patients with asthma, allergic rhinitis and rhinoconjunctivitis.200821748078
fungal control of pathogenic fungi isolated from wild plants in taif governorate, saudia arabia.twenty two plants were collected from taif governorate and identified as: euphorbia glomerifera, juniperus procera, launaea mucronata, capparis dcidua, punica granatum, opuntia ficus, prunus persica, eucalyptus globulus, medicago sativa, artemisia monosperma, trichodesma calathiforme, artemisia judaica, foeniculum vulgare, phagnalon sinaicum, rumex dentatus, asphodelus aestives, pulicaria crispa, launae sonchoides, forsskaolea tenacissima, arnebia hispidissima, avena spp and aerva lanata. pathog ...200718928069
fungal strains isolated from cork stoppers and the formation of 2,4,6-trichloroanisole involved in the cork taint of wine.cork taint is mainly due to 2,4,6-trichloroanisole (tca) produced through the activity of undesirable fungal strains. we observed that cfu mould number in tca-containing stoppers was not quantitatively different to that of the stoppers not containing tca (ca. 10(5)cfu/g). in contrast more fungi diversity was observed in tca-containing stoppers. penicillium spp (penicillium chrysogenum, penicillium glabrum), aspergillus spp (aspergillus niger and aspergillus oryzae), chrysonilia sitophila, mucor ...200717188205
mould germination: data treatment and modelling.the objectives of this study were i/ to examine germination data sets over a range of environmental conditions (water activity, temperature) for eight food spoilage moulds, ii/ to compare the ability of the gompertz equation and logistic function to fit the experimental plots, iii/ to simulate germination by assessing various distributions of the latent period for germination amongst a population of spores. data sets (percentage germination, p (%), versus time, t) of aspergillus carbonarius, asp ...200717188772
interactions between statins and penicillium chrysogenum antifungal protein (paf) to inhibit the germination of sporangiospores of different sensitive zygomycetes.this study reports on the antifungal activities of statins combined with an antifungal compound secreted by penicillium chrysogenum, paf. several species belonging in the class zygomycetes are considered to be agents of human or animal mycoses; other species have significance as postharvest plant pathogens. in the present work, four species (rhizopus stolonifer, mortierella wolfii, syncephalastrum racemosum and mycotypha africana) that exhibited different sensitivities to lovastatin and paf in p ...200717302920
removal of as(v) and as(iii) from water with a pei-modified fungal biomass.a novel biosorbent was prepared by chemically grafting polyethylenimine (pei) on the fungal biomass of penicillium chrysogenum through a two-step reaction. the pei-modified biomass was found to possess zero zeta potential at ph 10.4. owing to the protonation of amine groups on the biosorbent surface, the biosorbent is favourable for the removal of anionic arsenic species in water. the sorption capacity for as(v) at ph 3 increased by 5.7-fold after surface modification. the sorption performances ...200717305138
trans-splicing of an artificially split fungal mini-intein.inteins are internal protein domains found inside the coding region of different proteins. they can autocatalytically self-excise from their host protein and ligate the protein flanks, called exteins, with a peptide bond via a post-translational process called protein cis-splicing. in contrast, protein trans-splicing involves inteins split into an n- and a c-terminal domain. both domains are synthesized as two separate components and each joined to an extein; the intein domains can reassemble an ...200717316565
expression in escherichia coli and purification of bioactive antibacterial peptide abp-cm4 from the chinese silk worm, bombyx mori.the antibacterial peptide cm4 (abp-cm4), isolated from chinese bombys mori, is a 35-residue cationic, amphipathic alpha-helical peptide that exhibits a broad range of antimicrobial activity. to explore a new approach for the expression of abp-cm4 in e. coli, the gene abp-cm4, obtained by recursive pcr (rpcr), was cloned into the vector pet32a to construct a fusion expression plasmid. the fusion protein trx-cm4 was expressed in soluble form, purified by ni(2+)-chelating chromatography, and cleave ...200717375264
deacetylcephalosporin c production in penicillium chrysogenum by expression of the isopenicillin n epimerization, ring expansion, and acetylation genes.penicillium chrysogenum npe6 lacking isopenicillin n acyltransferase activity is an excellent host for production of different beta-lactam antibiotics. we have constructed p. chrysogenum strains expressing cefd1, cefd2, cefef, and cefg genes cloned from acremonium chrysogenum. northern analysis revealed that the four genes were expressed in p. chrysogenum. the recombinant strains ta64, ta71, and ta98 secreted significant amounts of deacetylcephalosporin c, but cephalosporin c was not detected in ...200717379148
toxins from strains of penicillium chrysogenum isolated from buildings and other sources.in 2004, scott et al. (mycologia 2004; 96: 1095-1105) determined that there are four molecular species within p. chrysogenum, one of which (clade 4) was dominant in isolates in house dust in approximately 100 homes in southern ontario, canada. we collected additional strains from buildings across canada and obtained some from daom. the large majority of our strains were in clade 4, with a modest number of strains in clade 1. because these strains came from across canada, the dominance of clade 4 ...200717380432
multi-objective optimization of an industrial penicillin v bioreactor train using non-dominated sorting genetic algorithm.bulk of the penicillin produced is used as raw material for semi-synthetic penicillin (such as amoxicillin and ampicillin) and semi-synthetic cephalosporins (such as cephalexin and cefadroxil). in the present paper, an industrial penicillin v bioreactor train is optimized for multiple objectives simultaneously. an industrial train, comprising a bank of identical bioreactors, is run semi-continuously in a synchronous fashion. the fermentation taking place in a bioreactor is modeled using a morpho ...200717405176
[reaction of microorganisms to the digestive fluid of the earthworms].the reaction of soil bacteria and fungi to the digestive fluid of the earthworm aporrectodea caliginosa was studied. the fluid was obtained by centrifugation of the native enzymes of the digestive tract. the inhibition of growth of certain bacteria, spores, and fungal hyphae under the effect of extracts from the anterior and middle sections of the digestive tract of a. caliginosa was discovered for the first time. in bacteria, microcolony formation was inhibited as early as 20-30 s after the app ...200717410875
reprogramming hansenula polymorpha for penicillin production: expression of the penicillium chrysogenum pcl gene.we aim to introduce the penicillin biosynthetic pathway into the methylotrophic yeast hansenula polymorpha. to allow simultaneous expression of the multiple genes of the penicillin biosynthetic pathway, additional markers were required. to this end, we constructed a novel host-vector system based on methionine auxotrophy and the h. polymorpha met6 gene, which encodes a putative cystathionine beta-lyase. with this new host-vector system, the penicillium chrysogenum pcl gene, encoding peroxisomal ...200717419769
xyloglucanases in the interaction between saprobe fungi and the arbuscular mycorrhizal fungus glomus mosseae.we studied the production of xyloglucanase enzymes of pea and lettuce roots in the presence of saprobe and arbuscular mycorrhizal (am) fungi. the am fungus glomus mosseae and the saprobe fungi fusarium graminearum, fusarium oxysporum-126, trichoderma harzianum, penicillium chrysogenum, pleurotus ostreatus and aspergillus niger were used. g. mosseae increased the shoot and root dry weight of pea but not of lettuce. most of the saprobe fungi increased the level of mycorrhization of pea and lettuce ...200716904235
comparative analysis of mixing distribution in aerobic stirred bioreactor for simulated yeasts and fungus broths.the study on mixing distribution for an aerobic stirred bioreactor and simulated (solutions of carboxymethylcellulose sodium salt), yeasts (s. cerevisiae) and fungus (p. chrysogenum pellets and free mycelia) broths indicated the significant variation of mixing time on the bioreactor height. the experiments suggested the possibility to reach a uniform mixing in whole bulk of the real broths for a certain value of rotation speed or biomass concentration domain. for s. cerevisiae broths the optimum ...200716909268
cytosolic nadph metabolism in penicillin-g producing and non-producing chemostat cultures of penicillium chrysogenum.this study addresses the relation between nadph supply and penicillin synthesis, by comparing the flux through the oxidative branch of the pentose phosphate pathway (ppp; the main source of cytosolic nadph) in penicillin-g producing and non-producing chemostat cultures of penicillium chrysogenum. the fluxes through the oxidative part of the ppp were determined using the recently introduced gluconate-tracer method. significantly higher oxidative ppp fluxes were observed in penicillin-g producing ...200717008114
combined effect of volatile antimicrobial agents on the growth of penicillium notatum.widely used antimicrobial volatile organic compounds, such as sulphur dioxide and ethanol but also selected aroma compounds such as carvacrol, allyl isothiocyanate (aitc) and cinnamaldehyde, were tested single and in binary combination for their effect on penicillium notatum growth in vapour phase at 30 degrees c. aroma compounds were more efficient compared to sulphur dioxide and ethanol. aitc and cinnamaldehyde had the highest inhibition activity on the growth of p. notatum with minimum inhibi ...200717011661
efficiency of penicillium chrysogenum ptcc 5037 in reducing low concentration of chromium hexavalent in a chromium electroplating plant wastewater.the effectiveness of penicillium chrysogenum was evaluated for reducing cr(vi) from the wastewater of a chromium electroplating plant. statistically-based experimental designs were applied to optimize the condition for reducing cr(vi) to cr(iii). by applying plackett-burman factorial design and central composite design as the optimization step, attempts were made to identify optimal values of the three factors that bringing about maximum microorganism activity and therefore maximum hexavalent ch ...200717035005
microbial and plant derived biomass for removal of heavy metals from wastewater.discharge of heavy metals from metal processing industries is known to have adverse effects on the environment. conventional treatment technologies for removal of heavy metals from aqueous solution are not economical and generate huge quantity of toxic chemical sludge. biosorption of heavy metals by metabolically inactive non-living biomass of microbial or plant origin is an innovative and alternative technology for removal of these pollutants from aqueous solution. due to unique chemical compos ...200716427277
response of fungal community in the unpolluted and polluted (textile and distillery wastes) habitats.37 fungal species were recorded, maximum found in textile wastewater polluted habitats (35) followed by unpolluted (15) and distillery polluted (6) habitats. fungal diversity in sediment samples of textile wastewater polluted habitats (25) was a little lower than wastewater samples (32), whereas it varied little both in the samples of unpolluted habitats (sambhar wetlands: 5-6; garden tanks: 9-10) and distillery waste (3-5). seasonal variation in species diversity was more pronounced in the text ...200718476401
yeast-like cell formation and glutathione metabolism in autolysing cultures of penicillium chrysogenum.the bulk formation of yeast-like (arthrospore-like) cells were typical in carbon-depleted submerged cultures of the high beta-lactam producer penicillium chrysogenum ncaim 00237 strain independently of the nitrogen-content of the culture medium. this morphogenetic switch was still quite common in carbon-starving cultures of the low-penicillin-producer strain p. chrysogenum atcc 28089 (wis 54-1255) when the nitrogen-content of the medium was low but was a very rare event in wild-type p. chrysogen ...200718277469
isolation and biochemical characterization of an antifungal peptide from amaranthus hypochondriacus seeds.an antifungal peptide, ay-amp, was isolated from amaranthus hypochondriacus seeds by acidic extraction and then purified by reverse-phase high-pressure liquid chromatography. the molecular mass of this peptide, as determined by mass spectrometry, is 3184 da. the peptide belongs to the superfamily of chitin-binding proteins, containing a single cysteine/glycine-rich chitin-binding domain, and it was found that ay-amp degrades chitin. ay-amp inhibits the growth, at very low doses, of different pat ...200718031007
antimicrobial activity of extracts of the lichen parmelia sulcata and its salazinic acid constituent.the antimicrobial activity of the acetone, chloroform, diethyl ether, methanol, and petroleum ether extracts of the lichen parmelia sulcata and its salazinic acid constituent have been screened against twenty eight food-borne bacteria and fungi. all of the extracts with the exception of the petroleum ether extract showed antimicrobial activity against aeromonas hydrophila, bacillus cereus, bacillus subtilis, listeria monocytogenes, proteus vulgaris, yersinia enterocolitica, staphylococcus aureus ...200717913083
degradation of metabolites of benzo[a]pyrene by coupling penicillium chrysogenum with kmno4.several main metabolites of benzo[a]pyrene (bap) formed by penicillium chrysogenum, benzo[a]pyrene-1,6-quinone (bp 1,6-quinone), trans-7,8-dihydroxy-7,8-dihydrobenzo[a]pyrene (bp 7,8-diol), 3-hydroxybenzo[a]pyrene (3-ohbp), were identified by high-performance liquid chromatography (hplc). the three metabolites were liable to be accumulated and were hardly further metabolized because of their toxicity to microorganisms. however, their further degradation was essential for the complete degradation ...200717915736
binding of the pta1 transcriptional activator to the divergent promoter region of the first two genes of the penicillin pathway in different penicillium species.the aim of this work is to establish the correlation between the transcriptional activator pta1 and the expression of the penicillin genes in different penicillin-producing strains. the level of expression of the first two genes of the penicillin pathway was clearly higher in penicillium chrysogenum than in penicillium notatum and penicillium nalgiovense. the divergent promoter pcbab-pcbc region contains binding sequences for several transcriptional factors that are conserved in p. notatum and p ...200717924108
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