A5069306721- Microbial Natural Products and Biosynthesis
- Trypanosoma species research and implications
- Genomics and Phylogenetic Studies
- Research on Leishmaniasis Studies
- Marine Sponges and Natural Products
- Biochemical and Molecular Research
- Alkaloids: synthesis and pharmacology
- Carbohydrate Chemistry and Synthesis
- Enzyme Structure and Function
- Chemical Synthesis and Analysis
- Synthesis and Biological Activity
- Plant-Microbe Interactions and Immunity
- Glycosylation and Glycoproteins Research
- Traditional and Medicinal Uses of Annonaceae
- Plant Toxicity and Pharmacological Properties
- Parasites and Host Interactions
- Bioactive Compounds and Antitumor Agents
- Biochemical Acid Research Studies
- Metabolomics and Mass Spectrometry Studies
- Phytochemical compounds biological activities
- Analytical Chemistry and Chromatography
- RNA and protein synthesis mechanisms
- Biochemical and Structural Characterization
- Synthetic Organic Chemistry Methods
- Amino Acid Enzymes and Metabolism
University of Ghana
2016-2025
Munzur University
2017-2019
University of Aberdeen
2006
Abstract The fluorinase is an enzyme that catalyses the combination of S ‐adenosyl‐ L ‐methionine (SAM) and a fluoride ion to generate 5′‐fluorodeoxy adenosine (FDA) through nucleophilic substitution reaction with as nucleophile. It only native fluorination has been characterised. was isolated in 2002 from Streptomyces cattleya , and, date, this source enzyme. Herein, we report three new isolates have identified by genome mining. novel fluorinases sp. MA37, Nocardia brasiliensis Actinoplanes...
Driven by increasing demand for the monitoring of industrial perfluorinated compounds (PFCs), identification novel fluorine containing (FOCs) and tracking organofluorine drugs their degradation products, there is a clear need sensitive, fluorine-specific detection unknown FOCs. Here we report first ever direct (speciation) method; capable individually detecting untargeted FOCs in environmental biological samples through application continuum source molecular absorption spectrometry (CS-MAS)...
Abstract Pyrrolizidine alkaloids (PAs) are a group of natural products with important biological activities. The discovery and characterization the multifunctional FAD‐dependent enzyme LgnC is now described. shown to convert indolizidine intermediates into pyrrolizidines through an unusual ring expansion/contraction mechanism, catalyze biosynthesis new bacterial PAs, so‐called legonmycins. By genome‐driven analysis, heterologous expression, gene inactivation, legonmycins were also originate...
Two novel polyketides, accraspiroketides A (1) and B (2), which feature unprecedented [6 + 6+6 6] [5 5] spiro chemical architectures, were isolated from Streptomyces sp. MA37 ΔaccJ mutant strain. Compounds 1-2 exhibit excellent activity against Gram-positive bacteria (MIC = 1.5–6.3 μg/mL). Notably, 1 2 have superior clinically Enterococcus faecium K60–39 4.0 μg/mL 4.7 μg/mL, respectively) than ampicillin 25
The isolation and characterization of bioactive metabolites from Streptomyces species continue to represent a vital area research, given their potential in natural product drug discovery. In this study, we characterize new siderophore called legonoxamine I, together with known compound, streptimidone, the talented soil bacterium sp. MA37, using chromatographic techniques spectroscopic analysis. Legonoxamine I is holo-siderophore, which likely be derailed biosynthetic pathway A. We also...
(2<italic>R</italic>3<italic>S</italic>4<italic>S</italic>)-5-Fluoro-2,3,4-trihydroxypentanoic acid (5-FHPA) has been discovered as a new fluorometabolite in the soil bacterium <italic>Streptomyces</italic> sp. MA37.
A new actinomycete strain Micromonospora sp. K310 was isolated from Ghanaian mangrove river sediment. Spectroscopy-guided fractionation led to the isolation of two compounds fermentation culture. One is butremycin (2) which (3-hydroxyl) derivative known Streptomyces metabolite ikarugamycin (1) and other compound a protonated aromatic tautomer 5′-methylthioinosine (MTI) (3). Both were characterized by 1D, 2D NMR MS data. Butremycin displayed weak antibacterial activity against Gram-positive...
In this paper we describe the identification of a new linaridin RiPP, legonaridin, from soil bacterium <italic>Streptomyces</italic> sp. CT34.
Drug-like molecules are known to contain many different building blocks with great potential as pharmacophores for drug discovery. The continued search unique scaffolds in our laboratory led the isolation of a novel Ghanaian soil bacterium, Streptomycessp. MA37. This strain produces bioactive molecules, most which belong carbazoles, pyrrolizidines, and fluorinated metabolites. Further probing metabolites MA37 has discovery new naphthacene-type aromatic natural product, we have named...
Whole-genome sequence data of the genus Streptomyces have shown a far greater chemical diversity metabolites than what been discovered under typical laboratory fermentation conditions. In our previous natural product discovery efforts on sp. MA37, bacterium isolated from rhizosphere soil sample in Legon, Ghana, we handful specialised this talented strain. However, analysis draft genome MA37 suggested that most encoded biosynthetic gene clusters (BGCs) remained cryptic or silent, and only...
Abstract Non-Ribosomal Peptide Synthetases (NRPSs) assemble a diverse range of natural products with important applications in both medicine and agriculture. They consist several multienzyme subunits that must interact each other highly controlled manner to facilitate efficient chain transfer, thus ensuring biosynthetic fidelity. Several mechanisms for transfer are known NRPSs, promoting structural diversity. Herein, we report the first biochemically characterized example type II...
Abstract Ribosomally synthesized and post-translationally modified peptides (RiPPs) are structurally complex natural products with diverse bioactivities. Here we report discovery of a RiPP, kintamdin, for which the structure is determined through spectroscopy, spectrometry genomic analysis to feature bis -thioether macrocyclic ring β-enamino acid residue. Biosynthetic investigation demonstrated that its pathway relies on four dedicated proteins: phosphotransferase KinD, Lyase KinC, kinase...
A new alkaloid paenidigyamycin (1) was obtained from the novel Ghanaian Paenibacillus sp. isolated mangrove rhizosphere soils of Pterocarpus santalinoides tree growing in wetlands Digya National Park, Ghana. Compound 1 on HPLC at tR = 37.0 min and its structure determined by MS, 1D, 2D-NMR data. When tested against L. major, (IC50 0.75 µM) just as effective amphotericin B 0.31 µM). Against donovani, 7.02 twenty-two times less active than 0.32 µM), reinforcing unique effectiveness major. For...
A new strategy for the identification of known compounds in Streptomyces extracts that can be applied discovery natural products is presented. The incorporates screening a database 5555 including 5098 structures from sp., using high-throughput LCMS data processing algorithm utilizes HRMS and predicted LC retention times (tR) as filters rapid product extract. database, named StrepDB, contains each compound structure, molecular formula, mass, time. All identified are annotated color coded...
Abstract β-Hydroxy-α-amino acids (βH-AAs) are key components of many bioactive molecules as well exist specialised metabolites. Among these βH-AAs, 4-fluorothreonine (4-FT) is the only naturally occurring fluorinated AA discovered thus far. Here we report overexpression and biochemical characterisation transaldolase from Streptomyces sp. MA37 (FTaseMA), a homologue FTase previously identified in biosynthesis 4-FT S. cattleya . FTaseMA displays considerable substrate plasticity to generate...
We report the structural characterization of a new pyrazinone analogue; butrepyrazinone, which was isolated from actinomycete strain Verrucosispora sp. K51G recovered Ghanaian mangrove river sediment. Spectroscopy-guided fractionation led to isolation compound fermentation culture and combination NMR spectroscopy, high-resolution mass spectrometry computer-aided calculations revealed that butrepyrazinone (10) possesses an unusual methylation pattern on ring. Butrepyrazinone (10), however,...
Streptomyces remains one of the prolific sources structural diversity, and a reservoir to mine for novel natural products. Continued screening new strains in our laboratory led isolation sp. RK44 from underexplored areas Kintampo waterfalls, Ghana, Africa. Preliminary metabolites this strain resulted characterization 2-alkyl-4-hydroxymethylfuran carboxamide (AHFA) 1 together with five known compounds, cyclo-(L-Pro-Gly) 2, cyclo-(L-Pro-L-Phe) 3, cyclo-(L-Pro-L-Val) 4, cyclo-(L-Leu-Hyp) 5,...
The biosynthetic origin of the C<sub>4</sub>alkyl side chain in “A” ring neocarazostatin A was reconstituted<italic>in vitro</italic>.
The ThDP-dependent enzyme NzsH catalyzes an acyloin condensation reaction using indole-3-pyruvate as the acyl acceptor in biosynthesis of Neocarazostatin A.
Four compounds (1–4) were isolated from the extracts of Streptomyces sp. CT37 using bioassay in conjunction with mass spectrometric molecular networking (MN) driven isolation. Their complete structures established by high-resolution electrospray ionization spectrometry (HR-ESIMS), and 1D 2D nuclear magnetic resonance (NMR) data. Legonimide 1 was identified as a new alkaloid containing rare linear imide motif its structure, while 2–4 already known their elucidated 1H-indole-3-carbaldehyde,...
More than 500 siderophores are known to date, but only three were identified be aryl-containing hydroxamate siderophores, legonoxamines A and B from <italic>Streptomyces</italic> sp. MA37, aryl ferrioxamine 2 <italic>Micrococcus luteus</italic> KLE1011.
Continued mining of natural products from the strain Streptomyces sp. MA37 in our laboratory led to discovery a minor specialized metabolite (SM) called accramycin A. Owing its low yield (0.2 mg/L) wild type strain, we investigated roles regulatory genes corresponding biosynthetic gene cluster (acc BGC) through inactivation with aim improving titer this compound. One resulting mutants (∆accJ) dramatically upregulated production A 1 by 330-fold (66 mg/L). Furthermore, ten new metabolites,...