A5078830676- Antifungal resistance and susceptibility
- Fungal Biology and Applications
- Pharmacogenetics and Drug Metabolism
- Microbial Natural Products and Biosynthesis
- Helminth infection and control
- Fungal Infections and Studies
- Nitrogen and Sulfur Effects on Brassica
- Peptidase Inhibition and Analysis
- Microbial Metabolic Engineering and Bioproduction
- Steroid Chemistry and Biochemistry
- Nail Diseases and Treatments
- Biochemical and Molecular Research
- Fungal Plant Pathogen Control
- Mycotoxins in Agriculture and Food
- Plant biochemistry and biosynthesis
- Synthesis and Biological Evaluation
- Microbial Metabolites in Food Biotechnology
- Phytase and its Applications
- Biofuel production and bioconversion
- Polysaccharides and Plant Cell Walls
- Leprosy Research and Treatment
- Phytochemical compounds biological activities
- Bacteriophages and microbial interactions
- Legionella and Acanthamoeba research
- Crop Yield and Soil Fertility
Swansea University
2013-2025
Viamet Pharmaceuticals (United States)
2017
University of Wales
2003-2007
Aberystwyth University
1994-2003
Rothamsted Research
2000-2002
University of Bristol
1996-1998
Summary A cDNA encoding a high‐affinity sulphate transporter has been isolated from barley by complementation of yeast mutant. The cDNA, designated HVST 1, encodes polypeptide 660 amino acids ( M r = 72 550), which is predicted to have 12 membrane‐spanning domains and extensive sequence homology with other identified eukaryotic transporters. K m for was 6.9 µM when the 1 expressed in mutant deficient gene SUL1 transporter. strong pH‐dependency uptake heterologously suggests that HVST1...
A clinical isolate of Candida albicans was identified as an erg5 (encoding sterol C22 desaturase) mutant in which ergosterol not detectable and ergosta 5,7-dienol comprised >80% the total fraction. The (CA108) resistant to fluconazole, voriconazole, itraconazole, ketoconazole, clotrimazole (MIC values, 64, 8, 2, 1, 2 microg ml(-1), respectively); azole resistance could be fully explained by activity multidrug pumps. When susceptibility tests were performed presence a efflux inhibitor...
ABSTRACT Sterol analysis identified four Candida albicans erg3 mutants in which ergosta 7,22-dienol, indicative of perturbations sterol Δ 5,6 -desaturase (Erg3p) activity, comprised >5% the total fraction. The (CA12, CA488, CA490, and CA1008) were all resistant to fluconazole, voriconazole, itraconazole, ketoconazole, clotrimazole under standard CLSI assay conditions (MIC values, ≥256, 16, 8, 1 μg ml −1 , respectively). Importantly, CA12 CA1008 retained an azole-resistant phenotype even...
ABSTRACT The binding and cytochrome P45051 (CYP51) inhibition properties of a novel antifungal compound, VT-1161, against purified recombinant Candida albicans CYP51 ( ERG11 ) Homo sapiens were compared with those clotrimazole, fluconazole, itraconazole, voriconazole. VT-1161 produced type II spectrum CYP51, characteristic heme iron coordination. affinity for was high (dissociation constant [ K d ], ≤39 nM) similar to that the pharmaceutical azole antifungals , ≤50 nM). In stark contrast, at...
ABSTRACT The genome sequence of the giant virus Acanthamoeba polyphaga mimivirus revealed presence two putative cytochrome P450 ( CYP ) genes. product one predicted genes (YP_143162) showed low-level homology to sterol 14-demethylase (CYP51) and contained a C-terminal polypeptide domain unknown function. YP_143162 expression (without an N-terminal membrane binding domain) in Escherichia coli yields protein which gives reduced CO difference maximum at 448 nm was formally demonstrated as first...
Candida albicans CYP51 (CaCYP51) (Erg11), full-length Homo sapiens (HsCYP51), and truncated Δ60HsCYP51 were expressed in Escherichia coli purified to homogeneity. CaCYP51 both HsCYP51 enzymes bound lanosterol (K(s), 14 18 μM) catalyzed the 14α-demethylation of using cytochrome P450 reductase NADPH as redox partners. Both clotrimazole, itraconazole, ketoconazole tightly (dissociation constants [K(d)s], 42 131 nM) but fluconazole (K(d), ~30,500 voriconazole ~2,300 weakly, whereas all five...
ABSTRACT We identified a clinical isolate of Candida glabrata (CG156) exhibiting flocculent growth and cross-resistance to fluconazole (FLC), voriconazole (VRC), amphotericin B (AMB), with MICs >256, 32 μg ml −1 , respectively. Sterol analysis using gas chromatography-mass spectrometry (GC-MS) revealed that CG156 was sterol 14α-demethylase (Erg11p) mutant, wherein 14α-methylated intermediates (lanosterol >80% the total) were only detectable sterols. ERG11 sequencing indicated harbored...
Purified Candida albicans sterol 14-α demethylase (CaCYP51) bound the CYP51 substrates lanosterol and eburicol, producing type I binding spectra with K(s) values of 11 25 μM, respectively, a K(m) value 6 μM for lanosterol. Azole to CaCYP51 was "tight" both II spectral intensity (ΔA(max)) azole concentration required obtain half-ΔA(max) being proportional concentration. Tight fluconazole itraconazole confirmed by 50% inhibitory determinations from reconstitution assays. had similar affinities...
Prothioconazole is a new triazolinthione fungicide used in agriculture. We have Candida albicans CYP51 (CaCYP51) to investigate the vitro activity of prothioconazole and consider use such compounds medical arena. Treatment C. cells with prothioconazole, prothioconazole-desthio, voriconazole resulted inhibition, as evidenced by accumulation 14α-methylated sterol substrates (lanosterol eburicol) depletion ergosterol. then compared inhibitor binding properties CaCYP51. observed that...
Two novel isolates of Candida glabrata exhibiting reduced sensitivity to amphotericin B (MIC, 8 μg ml(-1)) were found be ERG2 mutants, wherein Δ(8)-sterol intermediates comprised >90% the total cellular sterol fraction. Both harbored an alteration at Thr(121) in ERG2; corresponding residue (Thr(119)) Saccharomyces cerevisiae is essential for Δ8-Δ7 isomerization. This constitutes first report C. harboring mutations and B.
The profile of PC945, a novel triazole antifungal designed for administration via inhalation, was assessed in range vitro and vivo studies. PC945 characterized as potent, tightly binding inhibitor Aspergillus fumigatus sterol 14α-demethylase (CYP51A CYP51B) activity (50% inhibitory concentrations [IC50s], 0.23 μM 0.22 μM, respectively) with characteristic type II azole spectra. Against 96 clinically isolated A. strains, the MIC values ranged from 0.032 to >8 μg/ml, while those voriconazole...
ABSTRACT Cryptococcosis is a life-threatening disease often associated with HIV infection. Three Cryptococcus species CYP51 enzymes were purified and catalyzed the 14α-demethylation of lanosterol, eburicol, obtusifoliol. The investigational agent VT-1129 bound tightly to all three proteins (dissociation constant [ K d ] range, 14 25 nM) affinities similar those fluconazole, voriconazole, itraconazole, clotrimazole, ketoconazole ( 4 52 nM), whereas weakly human , 4.53 μM). was as effective...
Genes encoding cytochrome P450 (CYP; P450) enzymes occur widely in the Archaea, Bacteria, and Eukarya, where they play important roles metabolism of endogenous regulatory molecules exogenous chemicals. We now report that genes for multiple unique P450s commonly giant viruses Mimiviridae, Pandoraviridae, other families proposed order Megavirales. were also identified a herpesvirus (Ranid 3) phage (Mycobacterium Adler). The Adler was classified as CYP102L1, crystal structure open form solved...
Cysteine synthase (O-acetylserine (thiol) lyase, EC 4.2.99.8) and β-cyanoalanine (EC 4.4.1.9) have been isolated from leaves of Spinacea oleracea L. separated by anion-exchange chromatography. Further separation one minor two major isoforms cysteine was achieved hydrophobic interaction chromatography high resolution native electrophoresis (PAGE). Analysis root material indicated that amongst the multiple present, a single isoform predominated. Subcellular fractionation studies leaf forms, B,...
Aspergillus fumigatus sterol 14-α demethylase (CYP51) isoenzymes A (AF51A) and B (AF51B) were expressed in Escherichia coli purified. The dithionite-reduced CO-P450 complex for AF51A was unstable, rapidly denaturing to inactive P420, marked contrast AF51B, where the stable. Type I substrate binding spectra obtained with purified AF51B using lanosterol (K(s), 8.6 μM) eburicol 22.6 μM). Membrane suspensions of bound both 3.1 4.1 azoles, exception fluconazole, tight, K(d) (dissociation...
ABSTRACT Prothioconazole is one of the most important commercially available demethylase inhibitors (DMIs) used to treat Mycosphaerella graminicola infection wheat, but specific information regarding its mode action not in scientific literature. Treatment wild-type M. (strain IPO323) with 5 μg epoxiconazole, tebuconazole, triadimenol, or prothioconazole ml −1 resulted inhibition CYP51 (MgCYP51), as evidenced by accumulation 14α-methylated sterol substrates (lanosterol and eburicol) depletion...
Recombinant Candida albicans CYP51 (CaCYP51) proteins containing 23 single and 5 double amino acid substitutions found in clinical strains the wild-type enzyme were expressed Escherichia coli purified by Ni 2+ -nitrilotriacetic agarose chromatography. Catalytic tolerance to azole antifungals was assessed determination of concentration causing 50% inhibition (IC 50 ) using reconstitution assays.
A candidate CYP51 gene encoding sterol 14α-demethylase from the fish oomycete pathogen Saprolegnia parasitica (SpCYP51) was identified based on conserved residues among CYPs in genome. It heterologously expressed Escherichia coli, purified, and characterized. Lanosterol, eburicol, obtusifoliol bound to purified SpCYP51 with similar binding affinities (Ks, 3 5 μM). Eight pharmaceutical six agricultural azole antifungal agents tightly SpCYP51, posaconazole displaying highest apparent affinity...
1,2,4-trizole derivatives were designed to study their inhibition of Candida albicans CYP51 (IC 50 ), binding affinity ( K d ) and antifungal profile vs. wild-type resistant model fungal strains comparable with posaconazole.
A cyanoalanine synthase and two isoforms (A, cytosolic B, chloroplastic) of cysteine (O‐acetylserine (thiol) lyase) were isolated from spinach. N‐terminal amino acid sequence analysis the gave 100% homology for determined 12 residues with a published mitochondrial isoform. All three enzymes catalysed both synthesis reactions, although different efficiencies. Michaelis–Menten kinetics observed all when substrate saturation experiments performed varying O‐acetylserine, chloroalanine cysteine....
Sterol 14α-demethylase encoded by CYP51 is a member of the cytochrome P450 (CYP) superfamily enzymes and has been shown to have an essential role in sterol biosynthesis eukaryotes, with orthologues recently being described some bacteria. Examination genome sequence data for proteobacterium Methylococcus capsulatus, bacterial species known produce sterol, revealed presence single CYP strong homology CYP51, particularly form Mycobacterium tuberculosis. ThisM. capsulatus protein represents new...
A putative operon containing homologues of essential eukaryotic sterol biosynthetic enzymes, squalene monooxygenase and oxidosqualene cyclase, has been identified in the genome prokaryote Methylococcus capsulatus. Expression yielded a protein associated with membrane fraction, while expression cyclase soluble protein, contrasting enzyme forms. Activity studies purified revealed catalytic activity epoxidation 0.35 nmol produced/min/nmol monooxygenase, cyclization to lanosterol 0.6 no other...