Crystal structure of chorismate mutase from Burkholderia thailandensis

Burkholderia thailandensis is often used as a model for more virulent members of this genus of proteobacteria that are highly antibiotic-resistant and are potential agents of biological warfare that are infective by inhalation. As part of ongoing efforts to identify potential targets for the development of rational therapeutics, the structures of enzymes that are absent in humans, including that of chorismate mutase from B. thailandensis, have been determined by the Seattle Structural Genomics Center for Infectious Disease. The high-resolution structure of chorismate mutase from B. thailandensis was determined in the monoclinic space group P21 with three homodimers per asymmetric unit. The overall structure of each protomer has the prototypical AroQγ topology and shares conserved binding-cavity residues with other chorismate mutases, including those with which it has no appreciable sequence identity.

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Crystal structure of chorismate mutase fromBurkholderia phymatum

Acta Crystallographica Section F Structural Biology Communications ◽

10.1107/s2053230x18002868 ◽

2018 ◽

Vol 74 (4) ◽

pp. 187-192 ◽

Cited By ~ 1

Author(s):

Oluwatoyin A. Asojo ◽

Sandhya Subramanian ◽

Jan Abendroth ◽

Ilyssa Exley ◽

Donald D. Lorimer ◽

...

Keyword(s):

Crystal Structure ◽

Drug Development ◽

Structural Genomics ◽

Active Site ◽

Chorismate Mutase ◽

Biological Warfare ◽

Beneficial Bacteria ◽

Sequence Identity ◽

Resolution Structure

The bacteriumBurkholderia phymatumis a promiscuous symbiotic nitrogen-fixating bacterium that belongs to one of the largest groups of Betaproteobacteria. OtherBurkholderiaspecies are known to cause disease in plants and animals, and some are potential agents for biological warfare. Structural genomics efforts include characterizing the structures of enzymes from pathways that can be targeted for drug development. As part of these efforts, chorismate mutase fromB. phymatumwas produced and crystallized, and a 1.95 Å resolution structure is reported. This enzyme shares less than 33% sequence identity with other homologs of known structure. There are two classes of chorismate mutase: AroQ and AroH. The bacterial subclass AroQγ has reported roles in virulence. Chorismate mutase fromB. phymatumhas the prototypical AroQγ topology and retains the characteristic chorismate mutase active site. This suggests that substrate-based chorismate mutase inhibitors will not be specific and are likely to affect beneficial bacteria such asB. phymatum.

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The self-assembling zwitterionic form ofL-phenylalanine at neutral pH

Acta Crystallographica Section C Structural Chemistry ◽

10.1107/s2053229614002563 ◽

2014 ◽

Vol 70 (3) ◽

pp. 326-331 ◽

Cited By ~ 37

Author(s):

Estelle Mossou ◽

Susana C. M. Teixeira ◽

Edward P. Mitchell ◽

Sax A. Mason ◽

Lihi Adler-Abramovich ◽

...

Keyword(s):

Electron Microscopy ◽

Hydrogen Bonding ◽

The Self ◽

Monoclinic Space Group ◽

X Rays ◽

Asymmetric Unit ◽

Zwitterionic Form ◽

Self Assembling ◽

Hydrogen Bonding Interactions ◽

Resolution Structure

The title zwitterion (2S)-2-azaniumyl-1-hydroxy-3-phenylpropan-1-olate, C9H11NO2, also known as L-phenylalanine, was characterized using synchrotron X-rays. It crystallized in the monoclinic space groupP21with four molecules in the asymmetric unit. The 0.62 Å resolution structure is assumed to be closely related to the fibrillar form of phenylalanine, as observed by electron microscopy and electron diffraction. The structure exists in a zwitterionic form in which π–π stacking and hydrogen-bonding interactions are believed to form the basis of the self-assembling properties.

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Crystallization and preliminary diffraction data of neurotoxin Ts-γ from the venom of the scorpion Tityus serrulatus

Acta Crystallographica Section D Biological Crystallography ◽

10.1107/s0907444998007197 ◽

1998 ◽

Vol 54 (6) ◽

pp. 1440-1441 ◽

Cited By ~ 2

Author(s):

A. M. Golubev ◽

W.-H. Lee ◽

S. Marangoni ◽

J. C. Novello ◽

B. Oliveira ◽

...

Keyword(s):

Monoclinic Space Group ◽

Molecular Replacement ◽

Cell Parameters ◽

Apparent Homogeneity ◽

High Resolution Structure ◽

Ion Exchange Hplc ◽

Tityus Serrulatus ◽

Polyethylene Glycol 6000 ◽

Very High ◽

Resolution Structure

Scorpion neurotoxin Ts-γ was isolated from Tityus serrulatus venom and purified to apparent homogeneity by ion-exchange HPLC. Crystals of the toxin were grown using polyethylene glycol 6000 as precipitant and were found to belong to the monoclinic space group P21 with cell parameters a = 22.20, b = 36.90, c = 31.57 Å, β = 100.85°. The crystals diffract beyond 1.73 Å resolution at a synchrotron beamline, being notably stable during X-ray exposure. The structure has been solved by molecular replacement using the very high resolution structure of Sahara scorpion Androctonus australis Hector (PDB code 1AHO) as a search model.

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High-resolution structure determination by ALCHEMI

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100074707 ◽

1983 ◽

Vol 41 ◽

pp. 178-181 ◽

Cited By ~ 1

Author(s):

Peter G. Self ◽

Peter R. Buseck

Keyword(s):

Site Occupancy ◽

Real Space ◽

Unit Cell ◽

Bragg Angle ◽

Electron Current ◽

High Resolution Structure ◽

Beam Incident ◽

Crystallographic Planes ◽

Electron Beam Incident ◽

Resolution Structure

ALCHEMI (Atom Location by CHanneling Enhanced Microanalysis) enables the site occupancy of atoms in single crystals to be determined. In this article the fundamentals of the method for both EDS and EELS will be discussed. Unlike HRTEM, ALCHEMI does not place stringent resolution requirements on the microscope and, because EDS clearly distinguishes between elements of similar atomic number, it can offer some advantages over HRTEM. It does however, place certain constraints on the crystal. These constraints are: a) the sites of interest must lie on alternate crystallographic planes, b) the projected charge density on the alternate planes must be significantly different, and c) there must be at least one atomic species that lies solely on one of the planes.An electron beam incident on a crystal undergoes elastic scattering; in reciprocal space this is seen as a diffraction pattern and in real space this is a modulation of the electron current across the unit cell. When diffraction is strong (i.e., when the crystal is oriented near to the Bragg angle of a low-order reflection) the electron current at one point in the unit cell will differ significantly from that at another point.

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Cathodoluminescence of Catalyst Crystallites

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100055667 ◽

1982 ◽

Vol 40 ◽

pp. 664-665

Author(s):

E.D. Boyes ◽

P.L. Gai ◽

D.B. Darby ◽

C. Warwick

Keyword(s):

Defect Density ◽

Chemical Properties ◽

Operating Conditions ◽

Semiconductor Materials ◽

Environmental Cell ◽

High Resolution Structure ◽

Commercially Important ◽

Crystallographic Defects ◽

Resolution Structure

The extended crystallographic defects introduced into some oxide catalysts under operating conditions may be a consequence and accommodation of the changes produced by the catalytic activity, rather than always being the origin of the reactivity. Operation without such defects has been established for the commercially important tellurium molybdate system. in addition it is clear that the point defect density and the electronic structure can both have a significant influence on the chemical properties and hence on the effectiveness (activity and selectivity) of the material as a catalyst. SEM/probe techniques more commonly applied to semiconductor materials, have been investigated to supplement the information obtained from in-situ environmental cell HVEM, ultra-high resolution structure imaging and more conventional AEM and EPMA chemical microanalysis.

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