Unraveling biochemical properties of cockroach (Periplaneta americana) proteinases with a gel X-ray film contact print method

2005 ◽  
Vol 141 (3) ◽  
pp. 261-266 ◽  
Author(s):  
Vandana K. Hivrale ◽  
Nanasaheb P. Chougule ◽  
Pavan J. Chhabda ◽  
Ashok P. Giri ◽  
Manvendra S. Kachole
Keyword(s):  
Periplaneta Americana ◽  
Biochemical Properties ◽  
X Ray

Studies on Crop Function in the Cockroach (Periplaneta Americana L.)

1963 ◽  
Vol 40 (4) ◽  
pp. 763-773
Author(s):  
K. G. DAVEY ◽  
J. E. TREHERNE
Keyword(s):  
Mode Of Action ◽  
Periplaneta Americana ◽  
Methyl Cellulose ◽  
X Ray ◽  
A Minor

1. The structure and mode of action of the proventriculus are described. 2. X-ray photographs have shown that as the crop empties the decrease in volume of the fluid is partially compensated for by the swallowing of air. 3. The effects of various factors upon the rate of crop-emptying have been studied using solutions of different osmotic pressures. Changes in viscosity, effected by the addition of methyl cellulose, produce only a minor reduction in crop-emptying. The frequency of opening of the proventricular valve is not proportional to the rate of crop-emptying over the whole range of concentrations used, and it is assumed that changes in other parameters must affect the process.

scholarly journals Crystallization of the C-terminal redox domain of the sulfur-assimilatory enzyme APR1 fromArabidopsis thaliana

2014 ◽  
Vol 70 (9) ◽  
pp. 1211-1214 ◽  
Author(s):  
Fang-Fang Chen ◽  
Yu-Yung Chang ◽  
Chao-Cheng Cho ◽  
Chun-Hua Hsu
Keyword(s):  
Biochemical Properties ◽  
Diffusion Method ◽  
X Ray Diffraction ◽  
Plant Type ◽  
Unit Cell Parameters ◽  
X Ray ◽  
Cell Parameters ◽  
Functional Studies ◽  
Aps Reductase ◽  
Crystal Volume

Plant-type APS reductase (APR), which catalyzes the reduction of activated sulfate to sulfite in plants, consists of a reductase domain and a C-terminal redox domain showing sequence homology to thioredoxin but possessing the activity of glutaredoxin. In order to understand the structural and biochemical properties of the redox domain of plant-type APS reductase, the C-terminal domain of APR1 (APR1C) fromArabidopsis thalianawas crystallized using the sitting-drop vapour-diffusion method. X-ray diffraction data were collected to a resolution of 2.70 Å on the SPXF beamline BL13B1 at the NSRRC, Taiwan. The crystals belonged to space groupP43212 orP41212, with unit-cell parametersa=b= 58.2,c= 86.7 Å. With one molecule per asymmetric unit, the crystal volume per unit protein weight (VM) is 2.64 Å3 Da−1, which corresponds to a solvent content of approximately 53.49%. Further structure-based functional studies of APR1C would extend knowledge of the molecular mechanism and regulation of APR.

scholarly journals Multi-probe methods for investigating ion hydration

2014 ◽  
Vol 70 (a1) ◽  
pp. C720-C720
Author(s):  
Sofia Diaz-Moreno ◽  
Daniel Bowron
Keyword(s):  
Large Scale ◽  
Biochemical Properties ◽  
X Ray Diffraction ◽  
Ion Hydration ◽  
Neutron Sources ◽  
X Ray ◽  
Chemical Systems ◽  
The Past ◽  
Hydration Shells ◽  
X Ray Absorption

Techniques developed at large scale facilities such as X-ray synchrotrons and pulsed or reactor based neutron sources have, over the past few decades, played a significant role in unravelling many of the mysteries that underpin the chemical, physical and biochemical properties of ions in solutions. In this presentation we will illustrate how the combination of X-ray diffraction, neutron diffraction and X-ray absorption spectroscopy can be applied to the investigation of the structure of ion hydration shells. Examples of hydration of di- and tri-valent ions will be shown. In particular we will present an investigation of the hydration structure of copper (II) ions using this multi-technique approach, and discuss the findings in the context of biological and chemical systems.

Synthesis of 2,24-Diepicastasterone and 3,24-Diepicastasterone as Potential Brassinosteroid Metabolites of the Cockroach Periplaneta americana

2002 ◽  
Vol 67 (1) ◽  
pp. 91-102 ◽  
Author(s):  
Brunhilde Voigt ◽  
Andrea Porzel ◽  
Günter Adam ◽  
Dieter Golsch ◽  
Waldemar Adam ◽  
...  
Keyword(s):  
Periplaneta Americana ◽  
Reference Standards ◽  
Water Addition ◽  
X Ray ◽  
Epoxy Derivative ◽  
Metabolic Conversion ◽  
Acid Catalyzed

Investigations of the metabolic conversion of the phytohormone 24-epicastasterone (1) in the cockroach Periplaneta americana (L.) required the synthesis of 2,24-diepicastasterone (4), 3,24-diepicastasterone (7b) and 2-dehydro-3,24-diepicastasterone (9) as reference standards. 2,24-Diepicastasterone (4) was synthesized from 2α,3α-epoxy derivative 2 as well as from the 2β,3β-epoxy-22,23-diol 3 by acid-catalyzed water addition to the epoxy function leading to the desired 2β,3α-trans functionality. 3,24-Diepicastasterone (7b) was prepared by NaBH4-reduction of the 3-oxo derivative 6. Upon deprotection conditions from the ketol acetonides 6 and 8 in both cases 2-dehydro-3,24-diepicastasterone (9) was obtained. The structure of 2,24-diepicastasterone (4) was confirmed by X-ray analysis.

scholarly journals Biochemical Properties and Cytochemical Localization of Ouabain-insensitive, Potassium-dependent p-Nitrophenylphosphatase Activity in Rat Atrial Myocytes

1997 ◽  
Vol 45 (2) ◽  
pp. 177-187 ◽  
Author(s):  
Vadim S. Zinchuk ◽  
Toshihiro Kobayashi ◽  
Eva Garcia del Saz ◽  
Harumichi Seguchi
Keyword(s):  
Ventricular Myocytes ◽  
Reaction Medium ◽  
Biochemical Properties ◽  
Atrial Myocytes ◽  
Electron Microscopic ◽  
Cytochemical Localization ◽  
X Ray ◽  
T Tubules ◽  
P Type ◽  
Triton X

Enzyme activity that represents ouabain-insensitive, potassium-dependent p-nitrophenylphosphatase (p-NPPase) was assessed in rat atrial myocytes by biochemical and cytochemical procedures. No activity was detected in parallel experiments with ventricular myocytes. Fixed tissues were incubated in a reaction medium containing Tricine buffer, p-nitrophenylphosphate (p-NPP), KCl, MgCl2, CaCl2, CeCl3, Triton X-100, levamisole, and ouabain. Final pH was adjusted to 7.5. Biochemical studies showed that accumulation of p-nitrophenol in the medium was increased proportionally in accordance with the amount of incubated tissue. This activity was optimal with incubation at pH 7.5 and in the presence of KCl. Approximately 70% of the enzyme was inhibited by 2 mM CeCl3. Electron microscopic observations revealed reaction product (RP) at sites of ouabain-insensitive, potassium-dependent p-NPPase activity as electron-dense precipitate localized at the inner surface of the plasma membrane and at the T-tubules of atrial myocytes. Control experiments indicated that the activity was strongly inhibited by sodium orthovanadate and was repressed by omeprazole and 1,3-dicyclohexylcarbodiimide. X-ray microanalysis confirmed the presence of cerium within the cytochemical RP. The ouabain-insensitive, K-dependent p-NPPase activity detected in the present study is considered to be an isoform of a P-type, H-transporting, K-dependent adenosine triphosphatase (H,K-ATPase).

Ionic distribution in dopamine-stimulated NaCl fluid-secreting cockroach salivary glands

1983 ◽  
Vol 244 (2) ◽  
pp. R176-R186 ◽  
Author(s):  
B. L. Gupta ◽  
T. A. Hall
Keyword(s):  
Cell Membrane ◽  
Salivary Glands ◽  
Basal Cell ◽  
Periplaneta Americana ◽  
Ringer Solution ◽  
X Ray ◽  
Ionic Distribution ◽  
And Function ◽  
P Cells

The compound, racemose, innervated salivary glands of the cockroach Periplaneta americana closely resemble in structure and function the mammalian salivary glands (C.R. House, Biol. Rev. 55: 417-473, 1980). The quantitative distribution of Na, K, Cl, Ca, Mg, P, and S was investigated in the P-cells secreting isotonic NaCl and in duct lumens by using electron probe X-ray microanalysis of frozen-hydrated and frozen-dried cryosections. In the unstimulated glands in vitro the cells had (mmol/l cell-H2O) Na, 10; K, 110; Cl, 39 while the primary saliva had Na, 153; K, 4; Cl, 151. With 1 mumol dopamine in the bathing Ringer solution the P-cells had Na, 25; K, 177; Cl, 58 and the primary saliva, Na, 153; K, 26; Cl, 172. During passage through the ducts, the primary saliva was modified by an absorption of NaCl: more in unstimulated than in stimulated glands. It is proposed that the cells have a Na-K-ATPase both in the apical and basal cell membrane, as in vertebrate choroid plexus, and dopamine might increase the K and Na conductance of the basal cell membrane.

Biochemical Properties and Crystal Structure of Ethylmethylglyoxal Bis(guanylhydrazone) Sulfate — an Extremely Powerful Novel Inhibitor of Adenosylmethionine Decarboxylase

1986 ◽  
Vol 41 (9-10) ◽  
pp. 851-855 ◽  
Author(s):  
Hannu Elo ◽  
Ilpo Mutikainen ◽  
Leena Alhonen-Hongisto ◽  
Raija Laine ◽  
Juhani Janne ◽  
...  
Keyword(s):  
Diamine Oxidase ◽  
Competitive Inhibitor ◽  
Biochemical Properties ◽  
X Ray Diffraction ◽  
X Ray ◽  
Adenosylmethionine Decarboxylase ◽  
Diamine Oxidase Activity ◽  
Order Of Magnitude ◽  
Striking Contrast

Ethylmethylglyoxal bis(guanylhydrazone) (EMGBG) sulfate, an analog of the well-known antileukemic drug methylglyoxal bis(guanylhydrazone), was synthesized. It was shown to be an extremely powerful competitive inhibitor of eukaryotic S-adenosyimethionine decarboxylase, with an apparent Ki value 12 nᴍ. Thus, it appears to be the most powerful known inhibitor of the enzyme, being almost an order of magnitude more powerful than the corresponding ethylglyoxal derivative. It neither inhibited the proliferation of mouse L1210 leukemia cells in vitro, nor did it potentiate the growth inhibition produced by α-difluoromethyl ornithine. In this respect, its properties are closely related to those of dimethylglyoxal, ethylglyoxal and propylglyoxal bis(guanylhydrazones), while in striking contrast to those of the antiproliferative glyoxal and methylglyoxal analogs. EMGBG also inhibited intestinal diamine oxidase activity (Ki 0.7 μᴍ). EMGBG sulfate was crystallized from water, giving orthorhombic crystals (space group Pbcn). Their crystal and molecular structure was determined by X-ray diffraction methods. The carbon-nitrogen double bonds between the ethylmethylglyoxal part and the aminoguanidine moieties were found to have the same configuration as they are known to have in the salts of glyoxal. methylglyoxal and propylglyoxal bis(guanylhydrazones). The glyoxal bis(guanylhydrazone) chain of the EMGBG cation deviated strongly from planarity, thus differing dramatically from the corresponding chains of the glyoxal, methylglyoxal and propylglyoxal analogs.

Die Röntgenstrukturanalyse von 2-(m-Brombenzyl-4.7.8.9- tetra-O-acetyl-N-acetyl-α -ᴅ-neuraminsäure * / X-Ray-Structure-Analysis of 2-(m-Br-benzyl) -4,7,8,9-tetra-O-acetyl-N-acetyl- α-ᴅ-neuraminic Acid

1974 ◽  
Vol 29 (7-8) ◽  
pp. 317-322 ◽  
Author(s):  
H Wawra
Keyword(s):  
Structure Analysis ◽  
Absolute Configuration ◽  
Heavy Atom ◽  
Three Dimensional ◽  
Biochemical Properties ◽  
Neuraminic Acid ◽  
X Ray ◽  
The Absolute

Abstract The structure of 2-(m-Br-benzyl) -4,7,8,9-tetra-O-acetyl-N-acetyl-α-ᴅ-neuramine acid was solved by heavy-atom methods using three-dimensional X-ray data. Known biochemical properties of the molecule allow to determine the absolute configuration.

Space and Time Distribution of Hard X-Ray Emission in a Loop at the Beginning of a Flare

1994 ◽  
Vol 144 ◽  
pp. 275-277
Author(s):  
M. Karlický ◽  
J. C. Hénoux
Keyword(s):  
Time Distribution ◽  
Electron Bombardment ◽  
Spatial Evolution ◽  
Superthermal Electrons ◽  
Flare Loop ◽  
X Ray ◽  
Superthermal Electron ◽  
Flare Loops ◽  
Chromospheric Evaporation ◽  
Temporal And Spatial

AbstractUsing a new ID hybrid model of the electron bombardment in flare loops, we study not only the evolution of densities, plasma velocities and temperatures in the loop, but also the temporal and spatial evolution of hard X-ray emission. In the present paper a continuous bombardment by electrons isotropically accelerated at the top of flare loop with a power-law injection distribution function is considered. The computations include the effects of the return-current that reduces significantly the depth of the chromospheric layer which is evaporated. The present modelling is made with superthermal electron parameters corresponding to the classical resistivity regime for an input energy flux of superthermal electrons of 109erg cm−2s−1. It was found that due to the electron bombardment the two chromospheric evaporation waves are generated at both feet of the loop and they propagate up to the top, where they collide and cause temporary density and hard X-ray enhancements.

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