Books by Mike Williamson
Papers by Mike Williamson
Journal of the Chemical Society, Chemical Communications
ABSTRACT
Chemischer Informationsdienst
Journal of Magnetic Resonance (1969)
The chemical shifts of C"H protons have been calculated for nine proteins, on the basis of coordi... more The chemical shifts of C"H protons have been calculated for nine proteins, on the basis of coordinates taken from high-resolution crystal structures. Chemical shitts were calculated using ring-current shifts, shifts arising from magnetic anisotropies of bonds, and shifts arising from the polarizing effect of polar atoms on the P-H bond. The parameters used were refined iteratively to give the best fit to the experimentally observed shifts over the set of nine proteins and differ considerably from previously used values. The calculated shifts match experimental shifts with a correlation coefficient over all proteins of 0.78. The protein that was fitted best (ubiquitin) has a correlation coefficient of 0.86. The fit is poorest for conformationally mobile regions of the protein. The calculations reproduce closely the experimentally observed differences between chemical shifts for C"H in a-helix and B-sheet. o 1991 Academic press, hc. METHODS The chemical shift of C*H protons in proteins can be calculated by o = pi
Journal of Biomolecular NMR
ABSTRACT
Journal of the Chemical Society, Chemical Communications, 1982
Page 1. 344 J. CHEM. SOC., CHEM. COMMUN., 1982 On the Biosynthesis of the Antibiotic Vancomycin S... more Page 1. 344 J. CHEM. SOC., CHEM. COMMUN., 1982 On the Biosynthesis of the Antibiotic Vancomycin Stephen J. Hammond,a Michael P. Williamson,a Dudley H. Williams,*a Laverne D. Boeck,b and Gary 6. Marconib a University ...
Journal of Biomolecular NMR
ABSTRACT
Microbiology
The pathogenic neisseriae are fastidious bacteria that are only able to grow on a restricted rang... more The pathogenic neisseriae are fastidious bacteria that are only able to grow on a restricted range of carbon sources. The genome sequence of Neisseria meningitidis strain MC58 predicts the presence of a complete citric acid cycle (CAC), but there have been no detailed biochemical studies of carbon metabolism in this important pathogen. In this study, both NMR and conventional enzyme assays were used to investigate the central metabolic pathways of a serogroup B strain (K454). 13 C-NMR labelling patterns of amino acids from hydrolysed cell proteins after growth with either 2-or 3-[ 13 C]pyruvate were consistent with the operation of a complete oxidative CAC. Enzyme assays showed that cell-free extracts contained all the CAC enzymes predicted from the genome sequence, including a membrane-bound malate :quinone oxidoreductase which is present in place of the conventional NAD-linked cytoplasmic malate dehydrogenase. 1 H-NMR studies showed that growth on glucose, lactate and, especially, pyruvate, resulted in the excretion of significant amounts of acetate into the culture supernatant. This occurred via the phosphotransacetylase (PTA)-acetate kinase (ACK) pathway. Extremely high specific activities of PTA (7-14 µmol min N1 mg N1) were detected in cell-free extracts, although ACK activities were much lower (46-298 nmol min N1 mg N1). Expression of PTA and ACK activities was not co-ordinately regulated during growth on combinations of carbon sources. This may be related to the presence of two ackA paralogues in N. meningitidis which are, unusually, unlinked to the pta gene.
Journal of the Chemical Society, Perkin Transactions 1, 1985
ABSTRACT
The FASEB Journal
ABSTRACT
Journal of the Chemical Society, Chemical Communications, 1979
ABSTRACT
Journal of the Chemical Society, Chemical Communications, 1985
ABSTRACT
Journal of the Chemical Society, Perkin Transactions 1, 1988
... Siau-Gek Ang, Michael P. Williamson, and Dudley H. Williams* University Chemical Laboratory, ... more ... Siau-Gek Ang, Michael P. Williamson, and Dudley H. Williams* University Chemical Laboratory, Lensfield Road, Cambridge CB2 I EW ... G.1.c.- mass spectrometry performed on the ester derivatives confirmed the presence of 2,4-diaminobutyric acid in the hydrolysate. ...
Journal of Magnetic Resonance (1969), 1987
Photosynthesis research, 2000
The photosynthetic purple bacteria such as Rb. sphaeroides possesses an intracytoplasmic membrane... more The photosynthetic purple bacteria such as Rb. sphaeroides possesses an intracytoplasmic membrane (ICM) and a variety of pigment-binding membrane proteins located in the ICM, acting as photoreceptor. Such photosynthetic apparatus is concentrated in the ICM. It is composed of three multimeric membrane-bound proteins; light-harvesting complexes (LH 1, LH 2), a reaction center (RC) and a cytochrome b/c1 complex. We have purified these membranes, which are called chromatophores, and characterized the structure and dynamics of the photosynthetic membrane-bound proteins by means of multi-nuclear solid state NMR. First, the isotropic chemical shift of carbonyl carbons in natural abundance and [1-(13)C] Phe labeled chromatophores indicates that the membrane-bound proteins take mainly the helical conformation. Second, the chemical shifts of side-chain resonances of uniformly (15)N-labeled chromatophores indicate the side-chain histidine residue is mainly hydrogen bonded, whereas structural h...
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Books by Mike Williamson
Papers by Mike Williamson