Search Results

You searched for all publications:

with publication states 'Published (Approved)'

Search Again...

These results only include publications that have been reviewed and processed by Diamond Light Source. To also view papers that have not yet been processed click here.

You can use the folder icon under Actions to collate papers as required. You can then click on View Folder in the left-hand navigation to review and/or download your folder.

Exact matches
Related results

3 items found (0 items not approved), displaying all items.1

Instruments / Technical Area	Publication Details	Published
I03-Macromolecular Crystallography I04-1-Macromolecular Crystallography (fixed wavelength)	The 3D ‐structure, kinetics and dynamics of the E. coli nitroreductase NfsA with NADP+ provide glimpses of its catalytic mechanism Scott A. White , Andrew J. Christofferson , Alastair I. Grainger , Martin A. Day , David Jarrom , Antonio E. Graziano , Peter F. Searle , Eva I. Hyde Febs Letters DOI: 10.1002/1873-3468.14413 Show Abstract ▼ Abstract: Nitroreductases activate nitroaromatic antibiotics and cancer prodrugs to cytotoxic hydroxylamines and reduce quinones to quinols. Using steady-state and stopped-flow kinetics we show that the E. coli nitroreductase NfsA is 20-50 fold more active with NADPH than with NADH and that product release may be rate-limiting. The crystal structure of NfsA with NADP+ shows that a mobile loop forms a phosphate-binding pocket. The nicotinamide ring and nicotinamide ribose are mobile, as confirmed in molecular dynamics (MD) simulations. We present a model of NADPH bound to NfsA. Only one NADP+ is seen bound to the NfsA dimers, and MD simulations show that binding of a second NADP(H) cofactor is unfavourable, suggesting that NfsA and other members of this protein superfamily may have a half-of-sites mechanism.	Jun 2022
B23-Circular Dichroism	Intrinsic disorder in the partitioning protein KorB persists after cooperative complex formation with operator DNA and KorA Eva Hyde , Phillip Callow , Karthik V. Rajasekar , Peter Timmins , Trushar R. Patel , Giuliano Siligardi , Rohanah Hussain , Scott White , Christopher M. Thomas , David J. Scott Biochemical Journal DOI: 10.1042/BCJ20170281 Diamond Proposal Number(s): [14894, 16440] Open Access Show Abstract ▼ Abstract: The ParB protein, KorB, from the RK2 plasmid is required for DNA partitioning and transcriptional repression. It acts co-operatively with other proteins, including the repressor KorA. Like many multifunctional proteins, KorB contains regions of intrinsically disordered structure, existing in a large ensemble of interconverting conformations. Using NMR spectroscopy, circular dichroism, and small angle neutron scattering, we have studied KorB selectively within its binary complexes with KorA and DNA, and within the ternary KorA/KorB/DNA complex. The bound KorB protein remains disordered, with a mobile C-terminal domain and no changes in secondary structure but increases in the radius of gyration on complex formation. Comparison of wild type KorB with an N-terminal deletion mutant allows a model of the ensemble average distances between the domains when bound to DNA. We propose that the positive co-operativity between KorB, KorA and DNA results from conformational restriction of KorB on binding each partner, while maintaining disorder.	Jul 2017
I04-Macromolecular Crystallography	Synthesis of α-glucan in mycobacteria involves a hetero-octameric complex of trehalose synthase TreS and maltokinase Pep2 Rana Roy , Veeraraghavan Usha , Ali Kermani , David J. Scott , Eva I. Hyde , Gurdyal S. Besra , Luke Alderwick , Klaus Fütterer Acs Chemical Biology 8 (10) DOI: 10.1021/cb400508k PMID: 23901909 Diamond Proposal Number(s): [6388] Open Access Show Abstract ▼ Abstract: Recent evidence established that the cell envelope of Mycobacterium tuberculosis, the bacillus causing tuberculosis (TB), is coated by an α-glucan-containing capsule that has been implicated in persistence in a mouse infection model. As one of three known metabolic routes to α-glucan in mycobacteria, the cytoplasmic GlgE-pathway converts trehalose to α(1 → 4),α(1 → 6)-linked glucan in 4 steps. Whether individual reaction steps, catalyzed by trehalose synthase TreS, maltokinase Pep2, and glycosyltransferases GlgE and GlgB, occur independently or in a coordinated fashion is not known. Here, we report the crystal structure of M. tuberculosis TreS, and show by small-angle X-ray scattering and analytical ultracentrifugation that TreS forms tetramers in solution. Together with Pep2, TreS forms a hetero-octameric complex, and we demonstrate that complex formation markedly accelerates maltokinase activity of Pep2. Thus, complex formation may act as part of a regulatory mechanism of the GlgE pathway, which overall must avoid accumulation of toxic pathway intermediates, such as maltose-1-phosphate, and optimize the use of scarce nutrients.	Jul 2013

Publications Database

Search Results

You searched for all publications:

Search Again...

Subject Areas (check all that apply) select all

Instruments used to collect data (check all that apply) select all

Collaborations involved (check all that apply) select all

Diamond Offline Facilities used

Relevant Technical Areas (check all that apply) select all

Menu for Anonymous User