A5024959498- Microbial Natural Products and Biosynthesis
- Mass Spectrometry Techniques and Applications
- Analytical Chemistry and Chromatography
- Chemical Synthesis and Analysis
- Carbohydrate Chemistry and Synthesis
- Biochemical Acid Research Studies
- Amino Acid Enzymes and Metabolism
- Synthesis of heterocyclic compounds
- Forest ecology and management
- Biochemical and Molecular Research
- Synthesis and Biological Evaluation
- Antibiotics Pharmacokinetics and Efficacy
- Synthetic Organic Chemistry Methods
- Forest Ecology and Biodiversity Studies
- Enzyme Structure and Function
- Fire effects on ecosystems
- Synthesis and Characterization of Heterocyclic Compounds
- Metabolomics and Mass Spectrometry Studies
- Biopolymer Synthesis and Applications
- Advanced Chemical Sensor Technologies
- Chemical Reactions and Mechanisms
- Metabolism and Genetic Disorders
- Biotin and Related Studies
- Chemical Reaction Mechanisms
- Analytical chemistry methods development
Dalhousie University
2012-2024
John Cochran VA Medical Center
2023
St. Louis VA Medical Center
2023
Washington University in St. Louis
2023
Landstuhl Regional Medical Center
2015
US Forest Service
2006-2014
United States Department of Agriculture
2006
North Central College
2006
Morgantown High School
2006
Teesside University
2002
Isopenicillin N synthetase was extracted from Cephalosporium acremonium and purified about 200-fold. The product showed one major protein band, coinciding with activity, when subjected to electrophoresis in polyacrylamide gel. An isopenicillin Penicillium chrysogenum 70-fold by similar procedures. two enzymes resemble each other closely their Mr, mobility on gel requirement for Fe2+ ascorbate maximum activity. Preliminary experiments have shown that a can be Streptomyces clavuligerus.
<b>Objective</b> To evaluate whether an epidural steroid injection or gabapentin is a better treatment for lumbosacral radiculopathy. <b>Design</b> A multicenter randomized study conducted between 2011 and 2014. Computer generated randomization was stratified by site. Patients evaluating physicians were blinded to outcomes. <b>Settings</b> Eight military, Veterans Administration, civilian hospitals. <b>Participants</b> 145 people with radicular pain secondary herniated disc spinal stenosis...
Phytochemical investigations on the stem bark and roots of tropical shrub Clausena anisata led to isolation characterization three carbazole alkaloids: girinimbine, murrayamine-A ekeberginine; two peptide derivatives: aurantiamide acetate N-benzoyl-l-phenylalaninyl-N-benzoyl-l-phenylalaninate; a mixture phytosterols: sitosterol stigmasterol. The structures these compounds were established by nuclear magnetic resonance (1H-NMR, 13C-NMR, COSY, HSQC, HMQC, HMBC NOESY) spectroscopy electrospray...
Abstract The butyrate‐producing anaerobe Fusobacterium varium is an integral constituent of human gut microflora. Unlike many microorganisms, F. capable fermenting both amino acids and glucose. Although has been implicated in beneficial as well pathological bacterium–host interactions, its genome not sequenced. To obtain a better understanding the metabolic processes associated with acid fermentation by , we used gel‐based proteomic approach to examine changes soluble proteome accompanying...
The biosynthesis of isopenicillin N from delta-(L-alpha-aminoadipyl)-L-cysteinyl-D-valine in a cell-free system has been correlated wih O2 consumption by two methods, involving the use an oxygen-electrode and n.m.r. spectrometer respectively. results are consistent with 1 : stoichiometric ratio for dioxygen consumed to formed.
Fragmentation pathways have been studied on the monoanions formed during electrospray ionization of a wide range aliphatic dicarboxylic acids and their monoesters. All negative ion spectra were obtained from alcoholic or aqueous methanolic solutions without buffers adjustment pH, using either Finnigan LCQ trap VG-Micromass Quattro triple quadrupole mass spectrometer. collision-induced dissociation isotopic-labelling techniques. Two primary fragmentation acid observed, namely decarboxylation...
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTThiamin biosynthesis in yeast. Origin of the five-carbon unit thiazole moietyRobert L. White and Ian D. SpenserCite this: J. Am. Chem. Soc. 1982, 104, 18, 4934–4943Publication Date (Print):September 1, 1982Publication History Published online1 May 2002Published inissue 1 September 1982https://pubs.acs.org/doi/10.1021/ja00382a033https://doi.org/10.1021/ja00382a033research-articleACS PublicationsRequest reuse permissionsArticle...
Five ORFs were detected in a fragment from the Streptomyces venezuelae ISP5230 genomic DNA library by hybridization with PCR product amplified primers representing consensus of known halogenase sequences. Sequencing and functional analyses demonstrated that 11 12 (but not 13-15) extended partially characterized gene cluster for chloramphenicol (Cm) biosynthesis chromosome. Disruption ORF11 (cmlK) or ORF12 (cmlS) conjugal transfer insertionally inactivated genes to S. gave mutant strains...
Abstract The elucidation of the biosynthetic pathway to thiamin (Vitamin B 1 ) and its pyrophosphate ester, important coenzyme “cocarboxylase”, has challenged researchers for many years continues do so. problem origin can be separated into three parts: independent pathways pyrimidine moiety 4‐amino‐5‐hy‐droxymethyl‐2‐methylpyrimidine thiazole 5‐(2‐hydroxyethyl)‐4‐methylthiazole, route from these subunits vitamin. steps in latter process were fully established some twenty ago, it was shown...
The use of an on-line adsorption preconcentrator coupled with capillary zone electrophoresis/nanoelectrospray mass spectrometry (PC/CZE/nESMS) is described for the analysis peptides and protein digests. investigation was focused on production disposable preconcentrators made large particle size (40 μm irregular packing), thereby eliminating a retaining frit without loss performance. These preconcentration devices were commercially available components which can be easily interfaced to...
Eight additional genes, jadX, O, P, Q, S, T, U and V, in the jad cluster of Streptomyces venezuelae ISP5230, were located immediately downstream jadN by chromosome walking. Sequence analyses comparisons implicated them biosynthesis 2,6-dideoxysugar jadomycin B. The genes cloned Escherichia coli, inactivated inserting an apramycin resistance cassette with a promoter driving transcription transferred into intergeneric conjugation. Analysis HPLC NMR intermediates accumulated cultures...
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTCell-free biosynthesis of penicillins. Conversion peptides into new .beta.-lactam antibioticsGulam A. Bahadur, Jack E. Baldwin, John J. Usher, Edward P. Abraham, Gamini S. Jayatilake, and Robert L. WhiteCite this: Am. Chem. Soc. 1981, 103, 25, 7650–7651Publication Date (Print):December 1, 1981Publication History Published online1 May 2002Published inissue 1 December...
A proteome survey and MS analysis were conducted to investigate glucose metabolism in Fusobacterium varium, a butyrate-producing constituent of the indigenous human gut microflora. The bacterium was capable catabolizing as main energy source via Embden-Meyerhof-Parnas pathway. 2-DE analyses revealed that apparent concentrations six identified glycolytic enzymes (pyruvate kinase, enolase, glucose-6-phosphate isomerase, phosphoglycerate triosephosphate glyceraldehyde-3-phosphate dehydrogenase)...
Most media in which the growth of shaken submerged cultures Streptomyces akiyoshiensis was examined did not support formation well-dispersed mycelial suspensions. Investigation culture conditions promoting dispersed showed pH medium to be critical importance; an initial value 5.5 minimized aggregation mycelium while supporting adequate biomass production. In started at this pH, spore inocula gave better dispersal than vegetative inocula; with inocula, morphology also less affected by...
Abstract In contrast to the well‐described McLafferty rearrangement in odd‐electron cations, relatively little has been reported on comparable rearrangements even‐electron ions, especially negative ions. This work reports a systematic study using tandem mass spectrometry (MS/MS) fragment ion spectra of carboxylate anions having suitably acidic proton γ position. The process was studied both trap and triple quadrupole spectrometers; characteristic enolate stable neutral products were formed...
Radioactivity from [2-14C]glycine enters C-2 of the thiazole moiety thiamin and no other site, in Saccharomyces cerevisiae (strains A.T.C.C. 24903 39916, H.J. Bunker). L-[Me-14C]methionine or DL-[2-14C]tyrosine does not enter thiamin.
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTStereoisomers of allenic amines as inactivators monoamine oxidase type B. Stereochemical probes the active siteRoger A. Smith, Robert L. White, and Allen KrantzCite this: J. Med. Chem. 1988, 31, 8, 1558–1566Publication Date (Print):August 1, 1988Publication History Published online1 May 2002Published inissue 1 August 1988https://pubs.acs.org/doi/10.1021/jm00403a012https://doi.org/10.1021/jm00403a012research-articleACS PublicationsRequest reuse...