Radical Formation and Migration in Myoglobins

2003 ◽  
Vol 28 (1) ◽  
pp. 105-118 ◽  
Author(s):  
Dimitri A. Svistunenko ◽  
Brandon J. Reeder ◽  
Michael T. Wilson ◽  
Chris E. Cooper
Keyword(s):  
Protein Concentration ◽  
Peroxyl Radical ◽  
Sperm Whale ◽  
Radical Species ◽  
Primary Radical ◽  
Radical Concentration ◽  
Epr Signal ◽  
Radical Transfer ◽  
And Migration ◽  
Similar Decrease

Three EPR signals from individual free radical species have been identified in the EPR spectra of horse heart metmyoglobin (HH metMb) mixed with hydrogen peroxide (H2O2). The peroxyl radical EPR signal was assigned to the Trp14-OO• radical, the seven component signal – to the Tyr103• radical and the singlet EPR signal was assigned to the Tyr146• radical. Apo-Mb (haem free HH Mb) added in various concentrations to the native metMb prior to H2O2 addition affected the yields of the three types of radicals. As the concentrations of metMb and H2O2 were kept constant, the yield of the primary radical formed is the same in all experiments, H2O2 being unable to produce any radical in the reaction with a haem free protein. Nevertheless, the addition of apo-Mb resulted in an increase of the Tyr146• radical concentration and in a quantitatively similar decrease of the Tyr103• radical concentration. These changes were dependent on the concentration of the added apo-Mb. Thus we show that a radical transfer Tyr103• → Tyr146• occurs and that this reaction is protein concentration dependent. The question whether this radical transfer is inter- or intra-molecular is discussed. A similarity is drawn between the system studied and the sperm whale metMb/H2O2 system, for which the radical transfer Tyr103• → Tyr151• has been previously suggested.

scholarly journals When moult overlaps migration: moult-related changes in plasma biochemistry of migrating common snipe

PeerJ ◽  
2017 ◽  
Vol 5 ◽  
pp. e3057 ◽  
Author(s):  
Patrycja Podlaszczuk ◽  
Radosław Włodarczyk ◽  
Tomasz Janiszewski ◽  
Krzysztof Kaczmarek ◽  
Piotr Minias
Keyword(s):  
Total Protein ◽  
Protein Concentration ◽  
Plasma Concentrations ◽  
Plasma Biochemistry ◽  
Fat Reserves ◽  
Initial Stage ◽  
Gallinago Gallinago ◽  
The Common ◽  
Common Snipe ◽  
And Migration

Moult of feathers entails considerable physiological and energetic costs to an avian organism. Even under favourable feeding conditions, endogenous body stores and energy reserves of moulting birds are usually severely depleted. Thus, most species of birds separate moult from other energy-demanding activities, such as migration or reproduction. Common snipeGallinago gallinagois an exception, as during the first autumn migration many young snipe initiate the post-juvenile moult, which includes replacement of body feathers, lesser and median wing coverts, tertials, and rectrices. Here, we evaluated moult-related changes in blood plasma biochemistry of the common snipe during a period of serious trade-off in energy allocation between moult and migration. For this purpose, concentrations of basic metabolites in plasma were evaluated in more than 500 young snipe migrating through Central Europe. We found significant changes in the plasma concentrations of total protein, triglyceride and glucose over the course of moult, while the concentrations of uric acid and albumin did not change. Total protein concentration increased significantly in the initial stage of moult, probably as a result of increased production of keratin, but it decreased to the pre-moult level at the advanced stage of moult. Plasma triglyceride concentration decreased during the period of tertial and rectrice moult, which reflected depletion of endogenous fat reserves. By contrast, glucose concentration increased steadily during the course of moult, which could be caused by increased catabolism of triglycerides (via gluconeogenesis) or, alternatively, due to increased glucocorticoids as a stress response. Our results suggest that physiological changes associated with moult may be considered important determinants of the low pace of migration typical of the common snipe.

scholarly journals CONTENIDO DE GRASA Y PROTEINA EN Pygocentrus cariba, Prochilodus mariae, Plagioscion squamosissimus, Piaractus brachypomus e Hypostomus plecostomus EN UNA LAGUNA DE INUNDACION DEL ORINOCO MEDIO

2016 ◽  
Author(s):  
Ángel González ◽  
Arístide Márquez ◽  
William James Senior ◽  
Gregorio Martínez
Keyword(s):  
Analytical Chemistry ◽  
Chemical Composition ◽  
Protein Content ◽  
Protein Concentration ◽  
Variance Analysis ◽  
Muscular Tissue ◽  
Orinoco River ◽  
Commercial Importance ◽  
High Protein Concentration ◽  
And Migration

It was determined the concentration of fat and protein in the muscular tissue of 40 fish of each one of the species Pygocentrus cariba, Prochilodus mariae, Plagioscion squamosissimus, Piaractus brachypomus and Hypostomus plecostomus; captured in a lagoon flood of the middle Orinoco river using gillnets. The protein content and fat were determined by the methods of the Association of Official Analytical Chemistry (AOAC), being considered an average in the concentration of fat for P. cariba of 0.30 ± 0.01%; 0.60 ± 0.01% for H. plecostomus; 0.65 ± 0.01% for P. mariae; 0.90 ± 0.01% for P. squamosissimus and 1.55 ± 0.01% for P. brachypomus. The average in the protein concentration was of 19.60 ± 0.10% for P. mariae; 19.70 ± 0.13% for P. squamosissimus 19.70 ± 0.09% for H. plecostomus; 19.80 ± 0.15% for P. cariba and 19.80 ± 0.15% for P. brachypomus. A variance analysis (ANOVA) and a later test of Duncan it demonstrated differences statistically significant in the content of fat among species, with the bigger values of fat corresponding to P. brachypomus and P. squamosissimus and the smallest to P. cariba. The protein contents did not present significant differences. Seemingly the species P. cariba, P. mariae, P. squamosissimus, P. brachypomus and H. plecostomus, in general have a low content of fat and a high protein concentration, depending their concentrations mainly of the food, reproduction time and migration. This work constitutes a contribution to the knowledge of the chemical composition of these species, some of commercial importance as P. squamosissimus, P. brachypomus and P. mariae and other ecologically important as P. cariba and H. plecostomus.

Dielectric dispersion and dipole moment of myoglobin in water

1972 ◽  
Vol 328 (1574) ◽  
pp. 371-387 ◽  
Keyword(s):  
Crystal Structure ◽  
Dipole Moment ◽  
Protein Concentration ◽  
Hydration Shell ◽  
Sperm Whale ◽  
Dielectric Dispersion ◽  
Water Molecules ◽  
Solution Conductivity ◽  
Sperm Whale Myoglobin ◽  
Good Agreement

The parameters of dielectric dispersion at radio frequencies in aqueous solutions of horse and sperm whale myoglobin have been measured as functions of protein concentration, solution conductivity and temperature. From these dependences it is shown that, of the likely interpretations, the mechanism of molecular rotation is best able to account for the observed dispersion. The results are consistent with a dipole moment of around 150D for the myoglobin molecule and a hydration shell of about two water molecules thickness. This value of dipole moment is shown to be in good agreement with that obtained from calculations based on the known crystal structure.

scholarly journals Oxidation of Glyoxylic Acid by Cerium(IV):  Oxygen-Induced Enhancement of the Primary Radical Concentration

1996 ◽  
Vol 100 (30) ◽  
pp. 12342-12348 ◽  
Author(s):  
Bettina Neumann ◽  
Oliver Steinbock ◽  
Stefan C. Müller ◽  
Nar S. Dalal
Keyword(s):  
Glyoxylic Acid ◽  
Primary Radical ◽  
Radical Concentration

Demonstration of Retinal Glycogen with Silver Methenamine

1971 ◽  
Vol 29 ◽  
pp. 564-565
Author(s):  
A. W. Sedar ◽  
G. H. Bresnick
Keyword(s):  
Lactic Acid ◽  
Chromic Acid ◽  
Periodic Acid ◽  
Müller Cell ◽  
External Limiting Membrane ◽  
Electron Microscope Level ◽  
Reactive Process ◽  
Inner Limiting Membrane ◽  
Muller Cell ◽  
And Migration

After experimetnal damage to the retina with a variety of procedures Müller cell hypertrophy and migration occurs. According to Kuwabara and others the reactive process in these injuries is evidenced by a marked increase in amount of glycogen in the Müller cells. These cells were considered originally supporting elements with fiber processes extending throughout the retina from inner limiting membrane to external limiting membrane, but are known now to have high lactic acid dehydrogenase activity and the ability to synthesize glycogen. Since the periodic acid-chromic acid-silver methenamine technique was shown to demonstrate glycogen at the electron microscope level, it was selected to react with glycogen in the fine processes of the Müller cell that ramify among the neural elements in various layers of the retina and demarcate these cells cytologically. The Rhesus monkey was chosen as an example of a well vascularized retina and the rabbit as an example of a avascular retina to explore the possibilities of the technique.

Structure and migration of planar defects in crystals observed in atomic scale

1978 ◽  
Vol 36 (1) ◽  
pp. 284-285 ◽  
Author(s):  
H. Hashimoto ◽  
Y. Sugimoto ◽  
Y. Takai ◽  
H. Endoh
Keyword(s):  
Electron Microscope ◽  
Rotation Angle ◽  
Crystal Surface ◽  
Electron Gun ◽  
Atomic Scale ◽  
Present Observation ◽  
Twist Boundary ◽  
Optical Magnification ◽  
Zinc Crystal ◽  
And Migration

As was demonstrated by the present authors that atomic structure of simple crystal can be photographed by the conventional 100 kV electron microscope adjusted at “aberration free focus (AFF)” condition. In order to operate the microscope at AFF condition effectively, highly stabilized electron beams with small energy spread and small beam divergence are necessary. In the present observation, a 120 kV electron microscope with LaB6 electron gun was used. The most of the images were taken with the direct electron optical magnification of 1.3 million times and then magnified photographically.1. Twist boundary of ZnSFig. 1 is the image of wurtzite single crystal with twist boundary grown on the surface of zinc crystal by the reaction of sulphur vapour of 1540 Torr at 500°C. Crystal surface is parallel to (00.1) plane and electron beam is incident along the axis normal to the crystal surface. In the twist boundary there is a dislocation net work between two perfect crystals with a certain rotation angle.

Albumin-Induced Endocytic Vacuoles in Tetrahymena Pyrijormis

1975 ◽  
Vol 33 ◽  
pp. 694-695
Author(s):  
L. J. Brenner ◽  
D. G. Osborne ◽  
B. L. Schumaker
Keyword(s):  
Electron Microscopy ◽  
Bovine Serum Albumin ◽  
Bovine Serum ◽  
Protein Concentration ◽  
Tetrahymena Pyriformis ◽  
Sequence Of Events ◽  
Cytoplasmic Bodies ◽  
Food Vacuoles ◽  
Mouse Ascites ◽  
Normal Human

Exposure of the ciliate, Tetrahymena pyriformis, strain WH6, to normal human or rabbit sera or mouse ascites fluids induces the formation of large cytoplasmic bodies. By electron microscopy these (LB) are observed to be membrane-bounded structures, generally spherical and varying in size (Fig. 1), which do not resemble the food vacuoles of cells grown in proteinaceous broth. The possibility exists that the large bodies represent endocytic vacuoles containing material concentrated from the highly nutritive proteins and lipoproteins of the sera or ascites fluids. Tetrahymena mixed with bovine serum albumin or ovalbumin solutions having about the same protein concentration (7g/100 ml) as serum form endocytic vacuoles which bear little resemblance to the serum-induced LB. The albumin-induced structures (Fig. 2) are irregular in shape, rarely spherical, and have contents which vary in density and consistency. In this paper an attempt is made to formulate the sequence of events which might occur in the formation of the albumin-induced vacuoles.

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