Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Coprinus”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 487 records · Page 27Linked to original sources
PubMed1985

The significance of the spores of the Basidiomycetes (mushrooms and their allies) in bronchial asthma and allergic rhinitis.

The role of Basidiospores in the allergic diathesis is poorly understood. Dialyzed extracts of Agaricus campestris, Coprinus micaceus, Fuligo septica, Lycoperdon perlatum, Scleroderma lycoperdoides, Ustilago maydis, and sooty mold were prepared from fresh spores. The study group consisted of 100 patients with asthma and 100 patients with allergic rhinitis. These 200 patients had symptoms occurring during October and November. All were intradermally skin tested with the seven extracts at concentrations of 1 microgram/mL or 10 micrograms/mL. No scratch or pressure puncture tests were performed. Skin tests were recorded at 15 minutes (pos = 5-mm wheal with 10-mm erythema or greater) and at six or 24 hours (pos = 6 mm or greater of induration and erythema). A total of 436 immediate reactions were observed in the asthmatic group (4.4/patient) compared with 129 in the rhinitic group (1.3/patient). The late phase reactions were just the opposite. The asthmatic group had 66 late phase reactions or 0.7/patient compared with 382 or 3.8/patient in the rhinitic group. This study demonstrates that patients with bronchial asthma have a higher incidence of immediate skin sensitivity by intradermal testing, whereas patients with allergic rhinitis have late phase sensitivity to these fungal spores. This study was performed in the eastern United States only; therefore, the clinical significance of the results will become more apparent once this study is repeated in other parts of the country by other investigators.

Adolescent↗
PubMedDate not supplied

[Basidiomycetes in relation to antibiosis. II. Antibiotic activity of mycelia and culture liquids].

The author relates the results of the antibiotic activity of mycelia and culture liquids of 34 Basidiomycetes, tested against Escherichia coli, Staphylococcus aureus, Bacillus subtilis and Candida albicans. The mycelium disc test and the cylinder plate method were used, employing for the latter culture liquids at different ages. The most active against the three bacterial species were Psathyra spadiceo-grisea, Fistulina hepatica and Fomes pinicola; against S. aureus and B. subtilis, Lentinus edodes and Psilocybe coprophila; Coprinus phlyctidosporus, Lepista amara, Pholiota nameko, Pleurotus ostreatus 774 and 779, Schizophyllum commune, Stropharia melanosperma, Boletus felleus, Polyporus Schweinitzii and Trametes pini 786 are active only against B. subtilis. Psathyra spadiceo-grisea and Lentinus edodes showed activity against Candida albicans as well. Comparison is made of activity results of the strains employed with the currently accepted data in the literature for the same species.

Anti-Bacterial Agents↗
PubMed1982

[Boletus luridus and alcohol. Case report].

When ingested with alcohol, certain drugs (e.g. cephalosporins, sulfonylurea, metronidazole, griseofulvin, chloramphenicol), calcium cyanamide, dimethyl formamide and certain mushrooms cause a disulfiram-alcohol type reaction. Three cases of a disulfiram-alcohol type reaction after ingestion of Boletus luridus and alcohol are described. No serious symptoms were observed. In contrast to Coprinus atramentarius, the toxin of Boletus luridus is unknown.

Adult↗
PubMed2006

The laccase multi-gene family in Coprinopsis cinerea has seventeen different members that divide into two distinct subfamilies.

Seventeen non-allelic laccase genes and one gene footprint are present in the genome of Coprinopsis cinerea. Two gene subfamilies were defined by intron positions and similarity of deduced gene products, one with 15 members (lcc1-lcc15) and one with 2 members (lcc16, lcc17). The first subfamily divides in the phylogenetic tree of deduced proteins into smaller clusters that probably reflect recent gene duplication events. Different laccase genes diverged from each other both by frequent synonymous and non-synonymous codon changes. Mainly synonymous codon changes accumulate in alleles, with up to 12% total codon differences between given pairs of alleles. Overexpression of the 17 laccase genes under the control of a constitutive promoter identified nine active enzymes from subfamily 1. All of these showed laccase activities with DMP (2,6-dimethoxy phenol) as substrate but only eight of them also with ABTS [2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)]. Lcc16 and Lcc17 share certain sequence features with ferroxidases but enzyme assays failed to show such activity. Lcc15 is expected to be non-functional in laccase activity due to an internal deletion of about 150 amino acids. Transcripts were obtained from all genes but splice junctions for three genes were not congruent with translation into a functional protein.

Alleles↗
PubMed1996

Graviresponses in fungi.

Although the orientation of mycelial hyphal growth is usually independent of the gravity vector, individual specialised hyphae can show response to gravity. This is exemplified by the sporangiophore of Phycomyces, but the most striking gravitropic reactions occur in mushroom fruit bodies. During the course of development of a mushroom different tropisms predominate at different times; the young fruit body primordium is positively phototropic, but negative gravitropism later predominates. The switch between tropisms has been associated with meiosis. The spore-bearing tissue is positively gravitropic and responds independently of the stem. Bracket polypores do not show tropisms but exhibit gravimorphogenetic responses: disturbance leads to renewal of growth producing an entirely new fruiting structure. Indications from both clinostat and space flown experiments are that the basic form of the mushroom (overall tissue arrangement of stem, cap, gills, hymenium, veil) is established independently of the gravity vector although maturation, and especially commitment to the meiosis-sporulation pathway, requires the normal gravity vector. The gravity perception mechanism is difficult to identify. The latest results suggest that disturbance of cytoskeletal microfilaments is involved in perception (with nuclei possibly being used as statoliths), and Ca2(+)-mediated signal transduction may be involved in directing growth differentials.

Coprinus↗
PubMed1996

Oscillations in the peroxidase-oxidase reaction: a comparison of different peroxidases.

The nonlinear behavior of the peroxidase-oxidase reaction was studied using structurally different peroxidases. For the first time sustained oscillations with peroxidases other than horseradish peroxidase in a single-enzyme system were observed. All peroxidases that showed significant oxidase activity were able to generate sustained oscillations. When adjusting the overall reaction rate, either of the two modifiers 2,4-dichlorophenol or Methylene blue could be omitted from the reaction. Due to the observation of different enzyme intermediates when using different peroxidases, we conclude that the mechanisms responsible for oscillatory kinetics may vary from one peroxidase to the other.

Animals↗
PubMed2004

Structure and functional analysis of the fungal galectin CGL2.

Recognition of and discrimination between potential glyco-substrates is central to the function of galectins. Here we dissect the fundamental parameters responsible for such selectivity by the fungal representative, CGL2. The 2.1 A crystal structure of CGL2 and five substrate complexes reveal that this prototype galectin achieves increased substrate specificity by accommodating substituted oligosaccharides of the mammalian blood group A/B type in an extended binding cleft. Kinetic studies on wild-type and mutant CGL2 proteins demonstrate that the tetrameric organization is essential for functionality. The geometric constraints due to the orthogonal orientation of the four binding sites have important consequences on substrate binding and selectivity.

Binding Sites↗
PubMed2003

New insight into the peroxidase-hydroxamic acid interaction revealed by the combination of spectroscopic and crystallographic studies.

Aromatic hydroxamic acids, such as salicylhydroxamic (SHA) and benzohydroxamic (BHA) acids, are commonly used as probes for studying the active sites of peroxidases. In this paper, we have extended the study of the complexes of Arthromyces ramosus peroxidase (ARP/CIP) with BHA and SHA by analyzing their Raman spectra in solution and in single crystals. The experiments were carried out under various conditions to identify the best experimental conditions, and hence, avoid artifacts deriving from the preparation of the samples or collection of the spectra. The analysis of the data takes also into account the characteristic of the electronic absorption spectra in solution and the crystal structures of the complexes. The results showed small differences between the solution and the crystal phases even though the coordination state can be dramatically affected by the physical or chemical conditions. The greater sensitivity of the spectroscopic technique enabled us to establish the existence of multiple species upon complexation of the protein with the hydroxamic acids that could not be detected by ordinary X-ray crystallography. Furthermore, SHA titration experiments and singular value decomposition analysis of the absorption spectra indicated the presence of two binding sites in the protein, one with a high affinity (K(d) = 1.7 mM), which should correspond to the SHA bound protein as determined by X-ray, and the other with a very low affinity (K(d) > 80 mM) probably located in a non-heme site. This suggests that the heterogeneous titration line shape involves ligand binding to a non-heme site in competition with the canonical heme site. In contrast, the titration profile obtained with the BHA ligand is monophasic, in agreement with all the peroxidases so far studied.

Binding Sites↗
PubMed1997

Fluoride binding in hemoproteins: the importance of the distal cavity structure.

The electronic absorption and resonance Raman spectra of the fluoride complexes of various peroxidases and selected site-directed mutants have been studied at pH 5.0, and compared to the spectra obtained for the myoglobin-F adduct. It is shown that the electronic absorption maxima depend on the degree of conjugation between the porphyrin macrocycle and the vinyl substituents. Moreover, it is confirmed that the wavelength of the CT1 band is a sensitive probe of axial ligand polarity and of its interaction with the distal protein residues. The results highlight the different mechanism of stabilization of the fluoride ligand exerted by the distal residues in myoglobin and peroxidases. In peroxidases, the Arg is determinant in controlling the ligand binding via a strong hydrogen bond between the positively charged guanidinium group and the anion. Mutation of Arg to Leu decreases the stability of the complex by 900-fold, suggesting that this interaction stabilizes the complex by 4 kcal/mol. The distal His also contributes to the stability of the fluoride complex, presumably by accepting a proton from HF and hydrogen-bonding, through a water molecule, to the anion. Mutation of His to Leu decreases the stability of the fluoride complex by 30-fold, suggesting that this interaction is much weaker than the interaction with the distal Arg. For Mb, the distal His is solely responsible for stabilization of the exogenous ligand.

Binding Sites↗
PubMed2002

Intron gain and loss in the evolution of the conserved eukaryotic recombination machinery.

Intron conservation, intron gain or loss and putative intron sliding events were determined for a set of three genes (SPO11, MRE11 and DMC1) involved in basic aspects of recombination in eukaryotes. These are ancient genes and present in nearly all of the major kingdoms. MRE11 is of bacterial origin and can be found in all kingdoms. DMC1 is a specialized homolog of the bacterial RecA protein, whereas the SPO11 gene is of archaebacterial origin. Only unique homologs of SPO11 are found in animals and fungi whereas three distantly related SPO11 copies are present in plant genomes. A comparison of the respective intron positions and phases of all genes was performed, demonstrating that a quarter of the intron positions were perfectly conserved over more than 1 000 000 000 years. Regarding the remaining three quarters of the introns we found insertions to be about three times more frequent than deletions. Aligning the introns of the three different SPO11 homologs of Arabidopsis thaliana we propose a conclusive model of their evolution. We postulate that at least one duplication event occurred shortly after the divergence of plants from animals and fungi and that a respective homolog has been retained in a protist group, the apicomplexa.

Arabidopsis↗
PubMed1991

Structure-activity relationships of the nikkomycins.

The structure-activity relationships of different nikkomycins were studied to evaluate the structural requirements for a potent chitin synthase inhibitor. We investigated the transport of the nikkomycins via the peptide transport system of the yeast Yarrowia lipolytica and determined the kinetic parameters for nikkomycin Z uptake [Km = 24 microM, Vmax = 2.2 nmol min-1 (mg dry wt)-1]. We demonstrated that the beta-methyl group of the N-terminal amino acid of dipeptide nikkomycins protects the molecule against peptidase activity in crude cell-extracts of different fungi. Furthermore, the relationship between inhibition constants for chitin synthase, transport of the nikkomycins via the peptide transport system, susceptibility to degradation by cellular proteases and whole-cell activity of the nikkomycins are discussed.

Aminoglycosides↗
PubMed2005

Fatal pulmonary infection in a leukaemic patient caused by Hormographiella aspergillata.

A case of autopsy-proven fungal pneumonia in a relapsed leukaemia patient is reported. The fungus Hormographiella aspergillata was cultured from two bronchoalveolar fluid samples and identified through morphological examination and ITS2 sequence analysis. In addition, galactomannan was detected in eight consecutive serum samples, which suggested a co-infection with Aspergillus species. The patient was treated with caspofungin.

Adult↗
PubMed2000

Redox chemistry in laccase-catalyzed oxidation of N-hydroxy compounds.

1-Hydroxybenzotriazole, violuric acid, and N-hydroxyacetanilide are three N-OH compounds capable of mediating a range of laccase-catalyzed biotransformations, such as paper pulp delignification and degradation of polycyclic hydrocarbons. The mechanism of their enzymatic oxidation was studied with seven fungal laccases. The oxidation had a bell-shaped pH-activity profile with an optimal pH ranging from 4 to 7. The oxidation rate was found to be dependent on the redox potential difference between the N-OH substrate and laccase. A laccase with a higher redox potential or an N-OH compound with a lower redox potential tended to have a higher oxidation rate. Similar to the enzymatic oxidation of phenols, phenoxazines, phenothiazines, and other redox-active compounds, an "outer-sphere" type of single-electron transfer from the substrate to laccase and proton release are speculated to be involved in the rate-limiting step for N-OH oxidation.

Acetaminophen↗