Publications by authors named "Karl A Wilkinson"

We report a new species named that was isolated from the African fungus-growing plant-ant and show that it produces novel pentacyclic polyketides that are active against MRSA and VRE. The chemical scaffold of these compounds, which we have called the formicamycins, is similar to the fasamycins identified from the heterologous expression of clones isolated from environmental DNA, but has significant differences that allow the scaffold to be decorated with up to four halogen atoms. We report the structures and bioactivities of 16 new molecules and show, using CRISPR/Cas9 genome editing, that biosynthesis of these compounds is encoded by a single type 2 polyketide synthase biosynthetic gene cluster in the genome.

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We present a hybrid MPI-OpenMP implementation of Linear-Scaling Density Functional Theory within the ONETEP code. We illustrate its performance on a range of high performance computing (HPC) platforms comprising shared-memory nodes with fast interconnect. Our work has focused on applying OpenMP parallelism to the routines which dominate the computational load, attempting where possible to parallelize different loops from those already parallelized within MPI.

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Metal-ion-directed self-assembly has been used to construct kinetically inert, water-soluble heterometallic Ru2Re2 hosts that are potential sensors for bioanions. A previously reported metallomacrocycle and a new derivative synthesised by this approach are found to be general sensors for bioanions in water, showing an "off-on" luminescent change that is selective for nucleotides over uncharged nucleobases. Through a change in the ancillary ligands coordinated to the ruthenium centres of the host, an "off-on" sensor has been produced.

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Glycosylation of cellobiose hydrolase I (CBHI), is a key step in the processing and degradation of cellulose. Here the pathways and barriers of the reaction are explored using the free energy from adaptive reaction coordinate forces (FEARCF) reaction dynamics method coupled with SCC-DFTB/MM. In many respects CBHI follows the expected general GH7 family mechanism that involves the Glu-X-Asp-X-X-Glu motif.

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The approach used to calculate the two-electron integral by many electronic structure packages including generalized atomic and molecular electronic structure system-UK has been designed for CPU-based compute units. We redesigned the two-electron compute algorithm for acceleration on a graphical processing unit (GPU). We report the acceleration strategy and illustrate it on the (ss|ss) type integrals.

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Understanding carbohydrate ring pucker is critical to rational design in materials and pharmaceuticals. Recently we have generalized our adaptive reaction coordinate force biasing method to perform calculations on multidimensional reaction coordinates. We termed this the Free Energies from Adaptive Reaction Coordinate Forces (FEARCF) method.

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