A5035939824- Microbial Natural Products and Biosynthesis
- Carbohydrate Chemistry and Synthesis
- Glycosylation and Glycoproteins Research
- Chemical Synthesis and Analysis
- Crystallization and Solubility Studies
- X-ray Diffraction in Crystallography
- Synthetic Organic Chemistry Methods
- Marine Sponges and Natural Products
- Enzyme Production and Characterization
- RNA and protein synthesis mechanisms
- Biochemical and Molecular Research
- Enzyme Structure and Function
- Genomics and Phylogenetic Studies
- Biochemical and Structural Characterization
- Microbial Metabolic Engineering and Bioproduction
- Plant biochemistry and biosynthesis
- Plant-Microbe Interactions and Immunity
- Metabolomics and Mass Spectrometry Studies
- Molecular Junctions and Nanostructures
- Monoclonal and Polyclonal Antibodies Research
- Magnetism in coordination complexes
- Mass Spectrometry Techniques and Applications
- Enzyme Catalysis and Immobilization
- Fungal Biology and Applications
- Chemical synthesis and alkaloids
University of Warwick
2012-2024
Coventry (United Kingdom)
2015-2021
University of Cambridge
2008-2011
University College Dublin
2001-2009
Conway School of Landscape Design
2004
Abstract Non-ribosomal peptide synthetases are important enzymes for the assembly of complex natural products. Within these multi-modular lines, condensation domains perform central function chain assembly, typically by forming a bond between two peptidyl carrier protein (PCP)-bound substrates. In this work, we report structural snapshots domain in with an aminoacyl-PCP acceptor substrate. These structures allow identification mechanism that controls access substrates to active site domains....
The characterisation of scleric acid, a new natural product from silent and cryptic gene cluster genetically intractable bacteria, its biosynthesis are reported.
Participating acyl groups located at C-2 in glucosyl and related donors generally promote formation of 1,2-trans-glycosides. Reactions some glucuronic acid with TMSN3/SnCl4 or ROH/SnCl4 gave only the 1,2-cis-glycoside. The stereoselectivity is consistent participation C-6 group. methodology was used for synthesis a Kdn2en mimetic α-configuration.
The donor makes the difference: tin(IV) chloride catalyzed coupling of silyl ethers to donors derived from glucuronic acid has shown that (see scheme) are significantly better acceptors than corresponding alcohols or phenol. reactions highly stereoselective and dependant on structure. They provide 1,2-trans- 1,2-cis-(deoxy)glycosides in moderate excellent yields.
Caught in the act: Intermediates biosynthesis of lasalocid A are captured vivo by malonyl carba(dethia)-N-acetyl cysteamine probes. These species constitute novel snapshots timing ether and aromatic ring formation, thus providing valuable insights for reconstruction engineering polyether biosynthetic pathways. Detailed facts importance to specialist readers published as ”Supporting Information”. Such documents peer-reviewed, but not copy-edited or typeset. They made available submitted...
A novel mechanism is proposed for ring formation in the biosynthetic pathway to thiotetronate antibiotics thiolactomycin and Tü 3010.
Chemical probes capable of reacting with KS (ketosynthase)-bound biosynthetic intermediates were utilized for the investigation model type I iterative polyketide synthase 6-methylsalicylic acid (6-MSAS) in vivo and vitro. From fermentation fungal bacterial 6-MSAS hosts presence chain termination probes, a full range was isolated characterized first time. Meanwhile, vitro studies recombinant 6-MSA synthases both nonhydrolyzable hydrolyzable substrate mimics have provided additional insights...
The reaction of silylated nucleophiles with 6,1-anhydroglucopyranuronic acid (glucuronic 6,1-lactones) catalysed by tin(IV) chloride provides 1,2-trans or 1,2-cis (deoxy)glycosides in a manner dependent on the donor structure. alpha-glycoside was obtained for reactions 2-acyl group and 2-deoxydonors, whereas 2-deoxy-2-iodo gave beta-glycoside. Experimental evidence shows that when 1,2-cis-glycoside formation occurs, anomerisation initially formed 1,2-trans-glycosides SnCl(4) is possible....
The tandem mass spectrometry techniques electron-induced dissociation (EID) and collision-activated (CAD) have been compared as tools for providing detailed structural information of polyketides. Polyketides are an important class natural products that account a significant proportion the drugs currently in clinical use. Three polyketide products, namely erythromycin A, lasalocid iso-lasalocid were subjected to both CAD EID, their fragment ions assigned with sub-part-per-million accuracy....
In order to study intermediates in polyketide biosynthesis two nonhydrolyzable malonyl coenzyme A analogues were synthesised by a chemoenzymatic route. these the sulfur atom of CoA was replaced either methylene group (carbadethia analogue) or an oxygen (oxadethia analogue). These malonyl-CoA found compete with natural extender unit and trap from stilbene synthase, type III synthase (PKS). From reaction its phenylpropanoid substrates, diketide, triketide tetraketide species successfully...
The conjugation of carbohydrates to synthetic scaffolds has the goal preparing potent inhibitors lectin binding. We herein report synthesis a panel bivalent compounds (cyclophane and terephthalamide-derivatives) then used establish influence scaffold flexibility on respective inhibitory potency in medically relevant test system. Synthetic routes two phenylenediamine-based glycocyclophanes involving Ugi reactions glucuronic acid derivatives subsequent ring closing metathesis are described, as...
Modular biocatalysis is responsible for the generation of countless bioactive products and its mining remains a major focus drug discovery purposes. One enduring hurdles isolation biosynthetic intermediates in readily-analysed form. We prepared series nonhydrolysable pantetheine N-acetyl cysteamine mimics natural (methyl)malonyl extender units recruited polyketide formation. Using these analogues as competitive substrates, we were able to trap off-load diketide triketide species directly...
Ketoreductase enzymes are responsible for the generation of hydroxyl stereocentres during biosynthesis complex polyketide natural products. Previous studies isolated ketoreductases have shown that stereospecificity ketoreduction can be switched by mutagenesis selected active site amino acids. We show here in context intact synthase multienzyme same changes do not alter stereochemical outcome way. These findings point towards additional factors govern ketoreductase on multienzymes vivo.
Early-stage intermediates in the biosynthesis of erythromycin A by Saccharopolyspora erythraea were intercepted malonyl carba(dethia)-N-acetyl cysteamines, generated vivo from hydrolysis corresponding methyl esters.
Abstract A library of functionalized chemical probes capable reacting with ketosynthase‐bound biosynthetic intermediates was prepared and utilized to explore in vivo polyketide diversification. Fermentation ACP mutants S. lasaliensis the presence generated a range unnatural derivatives, including novel putative lasalocid derivatives characterized by variable aryl ketone moieties linear chains (bearing alkyne/azide handles fluorine) flanking polyether scaffold. By providing direct information...
Feeding of <italic>Ralstonia solanacearum</italic> with synthetic probes unravels the programming a partially reducing iterative type I polyketide synthase.
The solution structure of glycosyl amides has been studied by using NMR. A strong preference is displayed tertiary aromatic for E-anti structures in contrast with secondary where Z-anti predominate. structural diversity these classes molecules would seem to be important as the directional properties ring, or groups attached determined choosing have either a amide at anomeric center and could considered when designing bioactive carbohydrate scaffolds. analysis was also carried out related...
Polyketide natural products such as erythromycin A and epothilone are assembled on multienzyme polyketide synthases (PKSs), which consist of modular sets protein domains. Within these type I systems, the fidelity biosynthesis depends programmed interaction among multiple domains within each module, centered around acyl carrier (ACP). detailed understanding interdomain communication will therefore be vital for attempts to reprogram pathways by genetic engineering. We report here that between...
The thioesterase FlK from the fluoroacetate-producing Streptomyces cattleya catalyzes hydrolysis of fluoroacetyl-coenzyme A. This provides an effective self-defense mechanism, preventing any A formed being further metabolized to 4-hydroxy-trans-aconitate, a lethal inhibitor tricarboxylic acid cycle. Remarkably, does not accept acetyl-coenzyme as substrate. Crystal structure analysis shows that forms dimer, in which each subunit adopts hot dog fold observed for type II thioesterases. Unlike...
WS9326A is a peptide antibiotic containing highly unusual N-methyl-E-2-3-dehydrotyrosine (NMet-Dht) residue that incorporated during assembly on non-ribosomal synthetase (NRPS). The cytochrome P450 encoded by sas16 (P450Sas) has been shown to be essential for the formation of alkene moiety in NMet-Dht, but timing and mechanism P450Sas-mediated α,β-dehydrogenation Dht remained unclear. Here, we show substrate P450Sas NRPS-associated peptidyl carrier protein (PCP)-bound dipeptide intermediate...