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Matthew D Collins - One of the best experts on this subject based on the ideXlab platform.
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phylogenetic analysis of species of the meso Diaminopimelic Acid containing genera brevibacterium and dermabacter
International Journal of Systematic and Evolutionary Microbiology, 1994Co-Authors: Matthew D CollinsAbstract:16S rRNA gene sequencing studies were performed on Dermabacter hominis and four meso-Diaminopimelic Acid-containing species of the genus Brevibacterium. Phylogenetic analysis revealed a close association between Dermabacter hominis and representatives of the lysine-containing genera Arthrobacter, Micrococcus, and Renibacterium. By contrast, the genus Brevibacterium formed a distinct line of descent within the high-guanine-plus-cytosine-containing actinomycetes, displaying no specific affinity with any other organism examined.
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phylogenetic analysis of a new ll Diaminopimelic Acid containing coryneform bacterium from herbage nocardioides plantarum sp nov
International Journal of Systematic and Evolutionary Microbiology, 1994Co-Authors: Matthew D Collins, S Cockcroft, Sally WallbanksAbstract:The 16S rRNA gene sequence of a previously undescribed LL-Diaminopimelic Acid-containing coryneform bacterium isolated from herbage was determined in order to clarify the taxonomic position of this organism. A comparative sequence analysis revealed that the bacterium represents a new line of descent within the genus Nocardioides. On the basis of the results of a phylogenetic analysis and the phenotypic distinctiveness of the organism, a new species, Nocardioides plantarum, is proposed. The type strain is NCIMB 12834.
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phylogenetic analysis of some ll Diaminopimelic Acid containing coryneform bacteria from human skin description of propionibacterium innocuum sp nov
Fems Microbiology Letters, 1991Co-Authors: David Pitcher, Matthew D CollinsAbstract:A new species, Propionibacterium innocuum, is proposed to accomodate strains of coryneform bacteria from human skin with phenotypic characters similar to those of the classical propionibacteria but differing in exhibiting primarily aerobic respiration and possessing a unique cell wall composition in which LL-Diaminopimelic Acid and arabinose occur together. The partial 16S rRNA sequence confirms an affinity with the genus Propionibacterium and indicates that the species represents a distinct line within the genus. The type strain of Propionibacterium innocuum is NCTC 11082.
John C Vederas - One of the best experts on this subject based on the ideXlab platform.
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stereoselective syntheses of 4 oxa Diaminopimelic Acid and its protected derivatives via aziridine ring opening
Organic Letters, 2007Co-Authors: Vijaya R Pattabiraman, John C VederasAbstract:Regio- and stereoselective aziridine ring opening with oxygen nucleophiles derived from serine and threonine provides a route to stereochemically pure 4-oxa-2,6-Diaminopimelic Acid (oxa-DAP) and its methyl-substituted derivatives. Oxa-DAP is a substrate of DAP epimerase, a key enzyme for biosynthesis of l-lysine and formation of peptidoglycan precursors. Orthogonally protected analogues of lanthionine and β-methyllanthionine wherein oxygen replaces sulfur were prepared that could be used for solid-supported peptide synthesis to make oxa derivatives of lantibiotics.
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conjugate addition of radicals generated from diacyloxyiodobenzenes to dehydroamino Acid derivatives a synthesis of Diaminopimelic Acid analogues
Chemical Communications, 2002Co-Authors: Andrew Sutherland, John C VederasAbstract:Radical decomposition of bis((2S)-N-benzyloxycarbonyl-2-aminopentan-5-carboxy-1-methyl ester)iodobenzene followed by decarboxylation and subsequent conjugate addition with a series of selectively protected dehydroamino Acids leads to new analogues of Diaminopimelic Acid.
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the first isolation of an alkoxy n n dialkylaminodifluorosulfane from the reaction of an alcohol and dast an efficient synthesis of 2s 3r 6s 3 fluoro 2 6 Diaminopimelic Acid
Chemical Communications, 1999Co-Authors: Andrew Sutherland, John C VederasAbstract:During improvement of the synthesis of (2S,3R,6S)-3-fluoro-2,6-Diaminopimelic Acid 3, a potent inhibitor of DAP epimerase, a stable alkoxy-N,N-dialkylaminodifluorosulfane 9 was isolated from the reaction of alcohol 6 with DAST
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stereoselective synthesis of meso 2 6 Diaminopimelic Acid and its selectively protected derivatives
Journal of Organic Chemistry, 1998Co-Authors: Patricia Lanebell, John C VederasAbstract:Four synthetic routes to selectively protected derivatives and isomers of meso-Diaminopimelic Acid (DAP) (1a), a key constituent of bacterial peptidoglycan, were investigated. N-(tert-butyloxycarbonyl)-d-allylglycine (2) and N-(benzyloxycarbonyl)-l-allylglycine (4) were esterified to ethylene glycol and cyclized via olefin metathesis to a protected derivative 7 of 2,7-diaminosuberic Acid. Analogous linking of propane-1,3-diol with 2 and potential precursors of N-(benzyloxycarbonyl)-l-vinylglycine moieties, such as N-(benzyloxycarbonyl)-l-glutamate or N-(benzyloxycarbonyl)-l-methionine sulfoxide, gave 12 or 15, both of which produced the α,β-unsaturated ester 14 upon attempted generation of the vinylglycine precursor for olefin metathesis to DAP derivatives. An alternative route, based on SnCl4-catalyzed ene reaction of methyl N-(benzyloxycarbonyl)-l-allylglycinate (18) with glyoxylate esters of phenylcyclohexanol isomers as chiral auxiliaries, gave ca. 85:15 ratios of diastereomeric alcohols (19 or 20). T...
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effect of analogues of Diaminopimelic Acid on the meso diaminopimelate adding enzyme from escherichia coli
FEBS Letters, 1996Co-Authors: Genevieve Auger, John C Vederas, Jean Van Heijenoort, Didier BlanotAbstract:Several analogues of Diaminopimelic Acid (A2pm) were tested as substrates or inhibitors of the meso-diaminopimelate-adding enzyme from Escherichia coli. They included lanthionine derivatives, a phosphonic analogue, heterocyclic compounds, 3-fluoro-A2pm, 4-methylene-A2pm and N-hydroxy-A2pm. The best substrates were, in decreasing order of specific enzyme activity, (2S,3R,6S)-3-fluoro-A2pm, meso-lanthionine sulfoxide and N-hydroxy-A2pm (mixture of stereoisomers). In those cases where all the stereoisomers were available, the specificity could be described as meso ⪢ DD ≈ LL. N-Hydroxy-A2pm (mixture of stereoisomers) strongly inhibited the addition of radioactive meso-A2pm to UDP-N-acetylmuramoyl-dipeptide.
Sergio Sandri - One of the best experts on this subject based on the ideXlab platform.
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unusual peptides containing the 2 6 Diaminopimelic Acid framework stereocontrolled synthesis x ray analysis and computational modelling part 2
Tetrahedron-asymmetry, 2003Co-Authors: Roberta Galeazzi, Gianni Porzi, M Garavelli, Alessandro Grandi, Magda Monari, Sergio SandriAbstract:Abstract The stereocontrolled synthesis of peptides 6, 9 and 14, structural variants of 2,6-Diaminopimelic Acid, was carried out starting from the chiral synthon 1, easily obtained from l -valine. The configuration of the introduced stereogenic centres has been assigned on the basis of 1H NMR spectroscopic data. X-Ray crystal structure and conformation analysis of 5 are also reported.
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enantioselective synthesis of 2 6 Diaminopimelic Acid derivatives part 3
Tetrahedron-asymmetry, 2002Co-Authors: Francesca Paradisi, Fabio Piccinelli, Gianni Porzi, Sergio SandriAbstract:Abstract Enantiomerically pure 2,6-Diaminopimelic Acid derivatives 9a – c and 10a – c have been synthesized starting from the glycine-derived chiral synthon (1′ S ,1″ S )- 1 . The absolute configuration of stereocenters introduced on 2 and 3 were assigned on the basis of 1 H NMR data and conformational analysis.
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a new stereocontrolled synthesis of uncommon tripeptides derived from 2 6 Diaminopimelic Acid 2 6 dap
Tetrahedron-asymmetry, 2001Co-Authors: Francesca Paradisi, Gianni Porzi, Sergio SandriAbstract:Abstract The stereocontrolled synthesis of uncommon tripeptides 8 and 11a – c , structural variants of 2,6-Diaminopimelic Acid, was carried out starting from the mono-lactim ether 1 easily obtained from l -valine. The configurations of the introduced stereogenic centers were assigned on the basis of 1 H NMR spectroscopic data.
Gurdyal S Besra - One of the best experts on this subject based on the ideXlab platform.
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reconstruction of Diaminopimelic Acid biosynthesis allows characterisation of mycobacterium tuberculosis n succinyl l l Diaminopimelic Acid desuccinylase
Scientific Reports, 2016Co-Authors: Veeraraghavan Usha, Adrian J Lloyd, David I Roper, Christopher G Dowson, Guennadi Kozlov, Kalle Gehring, Smita Chauhan, Hasan T Imam, Claudia A Blindauer, Gurdyal S BesraAbstract:With the increased incidence of tuberculosis (TB) caused by Mycobacterium tuberculosis there is an urgent need for new and better anti-tubercular drugs. N-succinyl-L,L-Diaminopimelic Acid desuccinylase (DapE) is a key enzyme in the succinylase pathway for the biosynthesis of meso-Diaminopimelic Acid (meso-DAP) and L-lysine. DapE is a zinc containing metallohydrolase which hydrolyses N-succinyl L,L Diaminopimelic Acid (L,L-NSDAP) to L,L-Diaminopimelic Acid (L,L-DAP) and succinate. M. tuberculosis DapE (MtDapE) was cloned, over-expressed and purified as an N-terminal hexahistidine ((His)6) tagged fusion containing one zinc ion per DapE monomer. We redesigned the DAP synthetic pathway to generate L,L-NSDAP and other L,L-NSDAP derivatives and have characterised MtDapE with these substrates. In contrast to its other Gram negative homologues, the MtDapE was insensitive to inhibition by L-captopril which we show is consistent with novel mycobacterial alterations in the binding site of this drug.
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structure and function of mycobacterium tuberculosis meso Diaminopimelic Acid dap biosynthetic enzymes
Fems Microbiology Letters, 2012Co-Authors: Veeraraghavan Usha, Adrian J Lloyd, Andrew L Lovering, Gurdyal S BesraAbstract:Because of an increased emergence of resistance to current antitubercular drugs, there is a need for new antitubercular agents directed against novel targets. Diaminopimelic Acid (DAP) biosynthetic enzymes are unique to bacteria and are absent in mammals and provide a rich source of essential targets for antitubercular chemotherapy. Herein, we review the structure and function of the mycobacterial DAP biosynthetic enzymes.
Peter Schumann - One of the best experts on this subject based on the ideXlab platform.
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polyamine profiles within genera of the class actinobacteria with ll Diaminopimelic Acid in the peptidoglycan
International Journal of Systematic and Evolutionary Microbiology, 1999Co-Authors: Hansjurgen Busse, Peter SchumannAbstract:Polyamine patterns of coryne-and nocardioform representatives of the class Actinobacteria with ll-Diaminopimelic Acid in the peptidoglycan, comprising strains of the genera Aeromicrobium, Nocardioides, Intrasporangium, Terrabacter, Terracoccus, Propioniferax, Friedmanniella, Microlunatus, Luteococcus and Sporichthya, were analysed. The different polyamine patterns were in good agreement with the phylogenetic heterogeneity within this group of actinomycetes. Strains of the closely related genera Nocardioides and Aeromicrobium were characterized by the presence of cadaverine. The second cluster, consisting of the type strains of the species Friedmanniella antarctica, Propioniferax innocua, Microlunatus phosphovorus and Luteococcus japonicus displayed as a common feature the presence of the two predominant compounds spermidine and spermine. The presence of putrescine was common to the type strains of the species Intrasporangium calvum, Terrabacter tumescens and Terracoccus luteus. Sporichthya polymorpha, which is a representative of a separate line of descent, displayed spermidine as the predominant polyamine. These data indicate that polyamine patterns are suitable for the classification of actinomycetes with ll-Diaminopimelic Acid in the peptidoglycan.
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terracoccus luteus gen nov sp nov an ll Diaminopimelic Acid containing coccoid actinomycete from soil
International Journal of Systematic and Evolutionary Microbiology, 1997Co-Authors: Helmut Prauser, Peter Schumann, Frederick A Rainey, Reiner M Kroppenstedt, Erko StackebrandtAbstract:A gram-positive, aerobic actinomycete was isolated from soil. Spherical cells of this organism occur singly or form packets, which may cluster. The diagnostic diamino Acid of the cell wall peptidoglycan is LL-Diaminopimelic Acid. The predominate menaquinone is MK-8 (H4), and the main fatty Acids are 13-methyl tetradecanoic Acid and 12-methyl tetradecanoic Acid. The diagnostic polar lipids are phosphatidylethanolamine and phosphatidylinositol. The DNA base composition is 73 mol% G+C. Comparison of 16S ribosomal DNA sequences showed that this isolate is a phylogenetic neighbor of Terrabacter tumescens and Intrasporangium calvum. Genotypic, chemotaxonomic, morphological, and physiological characteristics are used to describe a new genus and species, Terracoccus luteus gen. nov., sp. nov. The type strain is strain IMET 7848 (= DSM 44267).
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friedmanniella antarctica gen nov sp nov an ll Diaminopimelic Acid containing actinomycete from antarctic sandstone
International Journal of Systematic and Evolutionary Microbiology, 1997Co-Authors: Peter Schumann, Erko Stackebrandt, Helmut Prauser, Frederick A Rainey, Peter HirschAbstract:A gram-positive, aerobic, slowly growing actinomycete was isolated from antarctic sandstone. Packets of spherical cells of this organism form clusters. The diagnostic diamino Acid of the peptidoglycan is LL-Diaminopimelic Acid with glycine in position 1 of the peptide subunit. The major menaquinone is MK-9(H4), and the main cellular fatty Acids are 12- and 13-methyltetradecanoic Acids. Only a few organic compounds are metabolized. The DNA base composition is 73 mol% G + C. A 16S ribosomal DNA sequence comparison showed that this isolate is a phylogenetic neighbor of the propionibacteria and related taxa. Its closest relative is Microlunatus phosphovorus. Morphological, physiological, and genotypic characteristics support the description of a new genus and new species, Friedmanniella antarctica gen. nov., sp. nov. The type strain is strain AA-1042 (= DSM 11053).