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المؤلفون: Elisabeth J. Forrestel, Emma C. Jardine, Gavin H. Thomas, Caroline E. R. Lehmann, Colin P. Osborne
المصدر: Journal of Biogeography. 47:553-565
مصطلحات موضوعية: 0106 biological sciences, 0303 health sciences, geography, geography.geographical_feature_category, Ecology, Specific leaf area, fungi, Biome, food and beverages, Biology, 010603 evolutionary biology, 01 natural sciences, Grassland, 03 medical and health sciences, Taxon, Trait, Poaceae, Leaf size, Soil fertility, Ecology, Evolution, Behavior and Systematics, 030304 developmental biology
الوصف: Aim The sorting of functional traits along environmental gradients is an important driver of community and landscape scale patterns of functional diversity. However, the significance of environmental factors in driving functional gradients within biomes and across continents remains poorly understood. Here, we evaluate the relationship of soil nutrients and climate to leaf traits in grasses (Poaceae) that are hypothesized to reflect different strategies of resource use along gradients of resource availability. Location Global. Taxon Poaceae. Methods We made direct measurements on herbarium specimens to compile a global dataset of functional traits and realized environmental niche for 279 grass species that are common in grassland and savanna biomes. We examined the strength and direction of correlations between pairwise trait combinations and measured the distribution of traits in relation to gradients of soil properties and climate, while accounting for phylogenetic relatedness. Results Leaf trait variation among species follows two orthogonal axes. One axis represents leaf size and plant height, and we showed positive scaling relationships between these size‐related traits. The other axis corresponds to economic traits associated with resource acquisition and allocation, including leaf tensile strength (LTS), specific leaf area (SLA) and leaf nitrogen content (LNC). Global‐scale variation in LNC was primarily correlated with soil nutrients, while LTS, SLA and size‐related traits showed weak relationships to environment. However, most of the trait variation occurred within different vegetation types, independent of large‐scale environmental gradients. Main conclusions Our work provides evidence among grasses for relationships at the global scale between leaf economic traits and soil fertility, and for an influence of aridity on traits related to plant size. However, large unexplained variance and strong phylogenetic signal in the model residuals imply that at this scale the evolution of functional traits is driven by factors beyond contemporary environmental or climatic conditions.
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المؤلفون: Anne-Kathrin Duhme-Klair, Lisa M. Miller, Reyme Herman, Thomas F. Krauss, Gavin H. Thomas, Ivan Gyulev
المصدر: RSC Advances. 10:36485-36494
مصطلحات موضوعية: 0303 health sciences, Penicillin binding proteins, Bioconjugation, 010405 organic chemistry, medicine.drug_class, Chemistry, General Chemical Engineering, Cephalosporin, Antibiotics, Substrate (chemistry), General Chemistry, Antimicrobial, 01 natural sciences, Combinatorial chemistry, 0104 chemical sciences, 03 medical and health sciences, polycyclic compounds, medicine, Pharmacophore, Molecular probe, 030304 developmental biology
الوصف: Molecular probes typically require structural modifications to allow for the immobilisation or bioconjugation with a desired substrate but the effects of these changes are often not evaluated. Here, we set out to determine the effects of attaching functional handles to a first-generation cephalosporin. A series of cephalexin derivatives was prepared, equipped with chemical tethers suitable for the site-selective conjugation of antibiotics to functionalised surfaces. The tethers were positioned remotely from the β-lactam ring to ensure minimal effect to the antibiotic's pharmacophore. Herein, the activity of the modified antibiotics was evaluated for binding to the therapeutic target, the penicillin binding proteins, and shown to maintain binding interactions. In addition, the deactivation of the modified drugs by four β-lactamases (TEM-1, CTX-M-15, AmpC, NDM-1) was investigated and the effect of the tethers on the catalytic efficiencies determined. CTX-M-15 was found to favour hydrolysis of the parent antibiotic without a tether, whereas AmpC and NDM-1 were found to favour the modified analogues. Furthermore, the antimicrobial activity of the derivatives was evaluated to investigate the effect of the structural modifications on the antimicrobial activity of the parent drug, cephalexin.
URL الوصول: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::b1ee73e1da92145f13fe94996f3a7a14
https://doi.org/10.1039/d0ra04893c -
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المؤلفون: Liam Nm Chapman, Benjamin J Willson, Gavin H. Thomas
المصدر: Current Opinion in Genetics & Development. :76-86
مصطلحات موضوعية: 0303 health sciences, Fusion, Bacteria, Membrane Proteins, Membrane Transport Proteins, Transporter, Computational biology, Biology, Ion Channels, Evolution, Molecular, 03 medical and health sciences, 0302 clinical medicine, Membrane, Protein Domains, Membrane protein, Genetics, Evolutionary dynamics, Gene, 030217 neurology & neurosurgery, Function (biology), Topology (chemistry), 030304 developmental biology, Developmental Biology
الوصف: The formation of complex multidomain proteins has occurred many times during evolution. For enzymes, this often confers the addition of new functions or new routes to regulate function. Herein we review how this same process has impacted on the function of membrane transporters and channels, proteins that, due to their integral membrane location, are potentially more constrained in the fusions they can accommodate. Using examples primarily from bacterial systems, we illustrate diverse instances of functional fusions and find evidence for promiscuous fusion partners that have fused to many different classes of membrane protein. We consider the evidence that topology and stoichiometry issues might limit the range of fusions that are selected in nature and attempt to find examples where a functional benefit of direct fusion over split proteins has been demonstrated. Finally, we consider whether the reverse process of gene fission has been important in membrane transporter evolution.
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المؤلفون: Gavin H. Thomas, Roderick E. Hubbard, Marcus Fischer, Johan P. Turkenburg, Shirley M. Roberts, Adam P. Hopkins, James A. Brannigan, John F. Darby, Seishi Shimizu
المصدر: Journal of the American Chemical Society. 141:15818-15826
مصطلحات موضوعية: Binding Sites, Protein Conformation, Virulence Factors, Chemistry, Water, General Chemistry, Protein engineering, Ligands, 010402 general chemistry, Ligand (biochemistry), 01 natural sciences, Biochemistry, Combinatorial chemistry, Catalysis, 0104 chemical sciences, Transport protein, Solvent, Viral Proteins, Colloid and Surface Chemistry, Protein sequencing, Solvents, Thermodynamics, Protein Binding
الوصف: Solvent organization is a key but underexploited contributor to the thermodynamics of protein-ligand recognition, with implications for ligand discovery, drug resistance, and protein engineering. Here, we explore the contribution of solvent to ligand binding in the
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المؤلفون: Gavin H. Thomas
المصدر: Microbiology
مصطلحات موضوعية: Actinobacteria, Biofilms, Microbiota, Editorials, Humans, Bacteriophages, Biology, Pseudomonas fluorescens, Microbiology, Bacillus subtilis, Mycobacterium, Plasmids
URL الوصول: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::d2d51da5721a35b264f9a4be161d602a
https://doi.org/10.1099/mic.0.001115 -
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المؤلفون: Louie M. K. Rombaut, Elliot J. R. Capp, Christopher R. Cooney, Emma C. Hughes, Zoë K. Varley, Gavin H. Thomas
المصدر: Evolution Letters
Evolution Letters, Vol 6, Iss 1, Pp 83-91 (2022)مصطلحات موضوعية: Allometry, Letter, evolutionary conservatism, Evolution, bird beaks, Genetics, QH359-425, Letters, constraints, Ecology, Evolution, Behavior and Systematics
الوصف: Evolution can involve periods of rapid divergent adaptation and expansion in the range of diversity, but evolution can also be relatively conservative over certain timescales due to functional, genetic-developmental, and ecological constraints. One way in which evolution may be conservative is in terms of allometry, the scaling relationship between the traits of organisms and body size. Here, we investigate patterns of allometric conservatism in the evolution of bird beaks with beak size and body size data for a representative sample of over 5000 extant bird species within a phylogenetic framework. We identify clades in which the allometric relationship between beak size and body size has remained relatively conserved across species over millions to tens of millions of years. We find that allometric conservatism is nonetheless punctuated by occasional shifts in the slopes and intercepts of allometric relationships. A steady accumulation of such shifts through time has given rise to the tremendous diversity of beak size relative to body size across birds today. Our findings are consistent with the Simpsonian vision of macroevolution, with evolutionary conservatism being the rule but with occasional shifts to new adaptive zones.
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المؤلفون: Gavin H. Thomas
المصدر: Microbiology
مصطلحات موضوعية: Chemistry, Editorials, Microbiology
URL الوصول: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::d1cacf151b0d0e3a114a0876b307d65d
https://doi.org/10.1099/mic.0.001107 -
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المؤلفون: Emma C. Hughes, David P. Edwards, Jen A. Bright, Elliot J.R. Capp, Christopher R. Cooney, Zoë K. Varley, Gavin H. Thomas
المصدر: Ecology lettersREFERENCES. 25(3)
مصطلحات موضوعية: Birds, Phenotype, Beak, Animals, Biodiversity, Biological Evolution, Ecology, Evolution, Behavior and Systematics
الوصف: Understanding the biogeographical patterns, and evolutionary and environmental drivers, underpinning morphological diversity are key for determining its origins and conservation. Using a comprehensive set of continuous morphological traits extracted from museum collections of 8353 bird species, including geometric morphometric beak shape data, we find that avian morphological diversity is unevenly distributed globally, even after controlling for species richness, with exceptionally dense packing of species in hyper-diverse tropical hotspots. At the regional level, these areas also have high morphological variance, with species exhibiting high phenotypic diversity. Evolutionary history likely plays a key role in shaping these patterns, with evolutionarily old species contributing to niche expansion, and young species contributing to niche packing. Taken together, these results imply that the tropics are both 'cradles' and 'museums' of phenotypic diversity.
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المؤلفون: Lisa M. Miller, Matthew D. Simmons, Callum D. Silver, Thomas F. Krauss, Gavin H. Thomas, Steven D. Johnson, Anne-Kathrin Duhme-Klair
المصدر: Nanoscale advances. 4(2)
مصطلحات موضوعية: General Engineering, General Materials Science, Bioengineering, General Chemistry, Atomic and Molecular Physics, and Optics
الوصف: Antimicrobial resistance (AMR) continues to threaten the effective treatment and prevention of bacterial infections. The spread of resistant infections is accelerated by the lack of fast and cost-effective tests for the detection of AMR at the point-of-care. We aimed to address this challenge by developing a diagnostic tool to detect one of the major forms of AMR, the β-lactamase enzymes. Antibiotic-functionalized gold nanoparticles (AuNPs) have been successfully developed for the detection of β-lactamases in challenging biological media, namely undiluted urine. Furthermore, these tools are compatible with samples containing a urine sample preservative (boric acid) or hematuria (blood). The functionalized AuNPs interact with the active β-lactamases, resulting in the hydrolysis of the surface-bound antibiotics, which then inhibits binding of the AuNPs to a capture protein (a penicillin-binding protein) to indicate the presence of active β-lactamases. We successfully integrated the antibiotic-functionalized AuNPs into a new lateral flow assay (LFA), which can be used to detect active β-lactamases down to the detection limit of 11 nM. While we demonstrate the use of antibiotic-functionalized AuNPs in an LFA format to provide a novel method of detecting active β-lactamases, these functionalized AuNPs are amenable to a range of alternative diagnostic technologies and could lead to vital point-of-care diagnostics for the early detection of multi-drug resistant infections.
URL الوصول: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::342a090cfe3e873c6fa95d92138fa45b
https://pubmed.ncbi.nlm.nih.gov/36132685 -
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المؤلفون: Gavin H. Thomas
المصدر: Microbiology. 167
مصطلحات موضوعية: Biology, Microbiology
URL الوصول: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::45416aea3219629fe6d7a950abb26153
https://doi.org/10.1099/mic.0.001090
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