The structure and function of glutamate receptors: Mg2+ block to X-ray diffraction

Many lines of evidence indicate that the oxygenation of hemoglobin is accompanied by changes in protein structure. Data on the oxygen equilibria of the hemoglobins from a number of animals are discussed in terms of this evidence. Evidence from studies of some hemoglobins (lamprey, frog and tadpole) indicates a major role for subunit dissociation equilibria in explaining two properties of the oxygen equilibria: heme–heme interaction and the "Bohr effect". The importance of subunit dissociation in mammalian hemoglobins is suggested by the known concentration dependence of the oxygen equilibria. Mammalian hemoglobins are composed of two types of polypeptide chains, α and β. The idea that the α and β subunits have different oxygen equilibria and are affected differently by pH is examined. It is concluded that the β-chains appear to play a major role in the mechanism of the Bohr effect not shared by the α-chains. This conclusion is supported by the structural changes in hemoglobin found to occur upon oxygenation by X-ray diffraction techniques.

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The Study of Calcium Oxide from Cockle Shell Used as a Low-Cost Catalyzer for Biodiesel Production

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.879.108 ◽

2018 ◽

Vol 879 ◽

pp. 108-112 ◽

Cited By ~ 1

Author(s):

Nisakorn Nuamsrinuan ◽

Pichet Limsuwan ◽

Kittisakchai Naemchanthara

Keyword(s):

Calcium Oxide ◽

Low Cost ◽

Structure And Function ◽

Biodiesel Production ◽

Resonance Spectroscopy ◽

X Ray Diffraction ◽

X Ray ◽

Function Group ◽

And Function ◽

Cockle Shell

In this paper, the cockle shell was studied as a catalyzer for biodiesel production. The cockle shell was heated at the various temperatures from 200 to 1300 °C for 4 h in the furnace. Then, the crystal structure and function group of unheated and heated cockle shell were characterized by X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR), respectively. The results indicated that the initial phase of cockle shell is aragonite phase. After heat at 400 °C, the aragonite phase transformed to calcite phase. Moreover, the calcite phase of cockle shell was completely changed to calcium oxide (CaO) after heated at 800 °C. Eventually, the yield of biodiesel used the CaO derived from cockle shell were determined by nuclear magnetic resonance spectroscopy (NMR). The results show that the CaO derived from cockle shell can be used as a catalyzer of biodiesel preparation. However, the biodiesel used CaO from cockle shell after heated at 1100 to 1300 °C as a catalyzer have the higher yield than other heated temperature. Finally, the results of this research indicated that the CaO from cockle shell could be used as a catalyst for biodiesel production.

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Relations between Structure and Function in Cytoplasmic Membrane Vesicles Isolated from an Escherichia coli Fatty-Acid Auxotroph. High-Angle X-Ray Diffraction, Freeze-Etch Electron Microscopy and Transport Studies

European Journal of Biochemistry ◽

10.1111/j.1432-1033.1974.tb03811.x ◽

1974 ◽

Vol 49 (1) ◽

pp. 61-76 ◽

Cited By ~ 127

Author(s):

Emanuel SHECHTER ◽

Lucienne LETELLIER ◽

Tadeusz GULIK-KRZYWICKI

Keyword(s):

Electron Microscopy ◽

Escherichia Coli ◽

Cytoplasmic Membrane ◽

Membrane Vesicles ◽

Structure And Function ◽

High Angle ◽

X Ray Diffraction ◽

X Ray ◽

Transport Studies ◽

And Function

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Crystal Structures of Fragments D and Double-D from Fibrinogen and Fibrin

Thrombosis and Haemostasis ◽

10.1055/s-0037-1615842 ◽

1999 ◽

Vol 82 (08) ◽

pp. 271-276 ◽

Cited By ~ 8

Author(s):

Glen Spraggon ◽

Stephen Everse ◽

Russell Doolittle

Keyword(s):

Electron Microscopy ◽

High Resolution ◽

Crystal Structures ◽

Structure And Function ◽

X Ray ◽

Long Period ◽

And Function

IntroductionAfter a long period of anticipation,1 the last two years have witnessed the first high-resolution x-ray structures of fragments from fibrinogen and fibrin.2-7 The results confirmed many aspects of fibrinogen structure and function that had previously been inferred from electron microscopy and biochemistry and revealed some unexpected features. Several matters have remained stubbornly unsettled, however, and much more work remains to be done. Here, we review several of the most significant findings that have accompanied the new x-ray structures and discuss some of the problems of the fibrinogen-fibrin conversion that remain unresolved. * Abbreviations: GPR—Gly-Pro-Arg-derivatives; GPRPam—Gly-Pro-Arg-Pro-amide; GHRPam—Gly-His-Arg-Pro-amide

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Betp - X-Ray Structure and Function of An Osmosensor and Transporter

Biophysical Journal ◽

10.1016/j.bpj.2009.12.268 ◽

2010 ◽

Vol 98 (3) ◽

pp. 46a

Author(s):

Reinhard Kraemer ◽

Susanne Ressl ◽

Vera Ott ◽

Sascha Nicklisch ◽

Heinz-Juergen Steinhoff ◽

...

Keyword(s):

Structure And Function ◽

X Ray ◽

And Function

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Evolutionary Conservation of Reactions in Translation

Microbiology and Molecular Biology Reviews ◽

10.1128/mmbr.66.3.460-485.2002 ◽

2002 ◽

Vol 66 (3) ◽

pp. 460-485 ◽

Cited By ~ 38

Author(s):

M. Clelia Ganoza ◽

Michael C. Kiel ◽

Hiroyuki Aoki

Keyword(s):

Molecular Mechanisms ◽

Tertiary Structure ◽

Evolutionary Conservation ◽

Initiation Factor ◽

Structural Studies ◽

X Ray Diffraction ◽

X Ray ◽

Common Features ◽

New Information ◽

And Function

SUMMARY Current X-ray diffraction and cryoelectron microscopic data of ribosomes of eubacteria have shed considerable light on the molecular mechanisms of translation. Structural studies of the protein factors that activate ribosomes also point to many common features in the primary sequence and tertiary structure of these proteins. The reconstitution of the complex apparatus of translation has also revealed new information important to the mechanisms. Surprisingly, the latter approach has uncovered a number of proteins whose sequence and/or structure and function are conserved in all cells, indicating that the mechanisms are indeed conserved. The possible mechanisms of a new initiation factor and two elongation factors are discussed in this context.

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Effects of Electron Beam on Structure and Physical Properties of Natural Colorless Topaz

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1125.60 ◽

2015 ◽

Vol 1125 ◽

pp. 60-63

Author(s):

Chutharat Paikaew ◽

Juthamas Inthanont ◽

Adisak Punyanut ◽

Ekachai Hoonnivathana ◽

Pichet Limsuwan ◽

...

Keyword(s):

Crystal Structure ◽

Electron Beam ◽

Physical Properties ◽

Orthorhombic Structure ◽

X Ray Diffraction ◽

X Ray ◽

Spin Resonance ◽

Function Group ◽

And Function ◽

Beam Dose

The purpose of this research was to investigate physical properties, configuration and color of topaz. Topazes were irradiated with electron beam linear accelerator at different dose from 40 to 180 MGy. The color of topaz was analyzed by UV-vis and it was shown that the color of topaz was becoming strong color with increased electron beam dose. Crystal structure and function group of topaz were characterized by X- ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy. The results showed that the topaz has orthorhombic structure and no other crystalline. After irradiated, topaz released OH indicating higher crystallinity of topaz and this was confirmed with the results of electron spin resonance (ESR). Electron beam dose response of topaz was investigated. ESR results showed that the Al3+ ion was substituted in Si4+ site and Ti3+ impurity in Al4+ site and this result corresponds to the results of FTIR. The experiment result indicated that electron beam could be making defect on crystal structure and color enhancement of topaz.

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