Proteins distribution

Aqueous-detergent solutions of appropriate concentration and temperature can phase separate to form two phases, one rich in detergents, possibly in the form of micelles, and the other depleted of the detergent (Piyde and Phillips, op. cit.). Proteins distribute between the two phases, hydrophobic (e.g., membrane) proteins reporting to the detergent-rich phase and hydrophilic proteins to the detergent-free phase. Indications are that the size-exclusion properties of these systems can also be exploited for viral separations. These systems would be handled in the same way as the aqueous two-phase systems. 

Wall, SJ, Yasada, RP, Hory, F, Flagg, S, Martin, BM, Ginns, El and Wolfe, BB (1991) Production of antisera selective for Mi muscarinic receptors using fusion proteins distribution of Ml receptors in rat brain. Mol. Pharmacol. 39 643-649. 

N Triadou, J Bataille, J Schmitz. Longitudinal study of the human intestinal brush border membrane proteins. Distribution of the main disaccharidases and peptidases. Gastroenterology 85 1326-1332, 1983. 

Cartwright [124] reported that miconazole was slightly absorbed from epithelial and mucosal surface. The drug is well absorbed from the gastrointestinal tract, but caused nausea and vomiting in some patients. The drug may be given intravenously but was associated phlebitis. Up to 90% of the active compound was bound to plasma protein. Distribution into other body compartments was poor. Metabolism was primarily in the liver, and only metabolites were excreted in the urine. At therapeutic levels, they were relatively nontoxic both locally and systematically, but occasionally produced disturbances on the central nervous system. 

Figure 21.8 Comparison of IMS indicating protein distribution in the rat brain section corresponding to Figure 21.7 (a-c) the spray-droplet (a), droplet (b), and spray-coating (c) methods are used. Reprinted with permission from Sugiura et al.7 See color insert.

Fluorescence spectroscopy and its applications to the physical and life sciences have evolved rapidly during the past decade. The increased interest in fluorescence appears to be due to advances in time resolution, methods of data analysis and improved instrumentation. With these advances, it is now practical to perform time-resolved measurements with enough resolution to compare the results with the structural and dynamic features of macromolecules, to probe the structures of proteins, membranes, and nucleic acids, and to acquire two-dimensional microscopic images of chemical or protein distributions in cell cultures. Advances in laser and detector technology have also resulted in renewed interest in fluorescence for clinical and analytical chemistry. 

Skalko N, Bouwstra J, Spies F, Gregoriadis G. The effect of microfluidization of protein-coated liposomes on protein distribution on the surface of generated small vesicles. Biochim Biophys Acta 1996 1301 249-254. 

Iron-sulfur clusters constitute one of the most ancient, ubiquitous, and structurally and functionally diverse classes of biological prosthetic groups. For reviews see Cammack (1992), Johnson (1994, 1998), Beinert et al. (1997), Beinert and Kiley (1999), and Beinert (2000). Indeed there are now known to be in excess of 120 distinct types of Fe-S cluster-containing enzymes and proteins, distributed over all three kingdoms of life, and the list is growing rapidly. 

Fig. 1. (opposite page) Distribution of FITC-conjugated BSA in various fibroblast cell lines under different fixation/permeabilization regimes. (A-D) Protein distribution in living cells (A) PtKj, (B) CHO, (C) 3T3, and (D) HeLa cells. The protein is excluded from the nuclei of all cells. (E-H) Protein distribution in cells extracted for 10 min with 0.1% Triton X-100 before fixation for 30 min with 3.7% formaldehyde (E) PtKi, (F) CHO, (G) 3T3, and (H) HeLa cells. Nuclear fluorescence is seen in (E) PtKj and (G) 3T3 cells. (I-L) Protein distribution in cells extracted for 10 min with 1% Triton X-100 before fixation for 30 min with 3.7% formaldehyde (I) PtKj, (J) CHO, (K) 3T3, and (L) HeLa cells. No fluorescence is detected in the cells with the exception of some nuclear fluorescence seen in (L) HeLa cells. (M-P) Protein distribution in cells fixed for 30 min with 3.7% paraformaldehyde before permeabilization for 10 min with 0.1% Triton X-100. Fluorescence is seen primarily in the cytoplasm with the exception that nuclear fluorescence is seen in (M) PtKi and (N) CHO cells. (Q-T) Protein distributions in cells fixed for 5 min with 90% methanol, 50 vaM EGTA at -20°C (Q) PtKj, (R) CHO, (S) 3T3, and (T) HeLa cells. All cells show an overall low fluorescence, fibrous-textured cytoplasmic fluorescence, and bright staining at the periphery of the nucleus. 10 mm per scale division (black bar). (Reproduced with permission from ref. 6.)... 

Zoladek, T., A. Tobiasz, G. Vaduva, M. Boguta, N. C. Martin, and A. K. Hopper. MDPI, a Saccharomyces cerevisiae gene involved in mitochondrial/ cytoplasmic protein distribution, is identical to the ubiquitin-protein ligase gene RSP5. Genetics. 145 595-603. 1997. 

Uzunbajakava, N., Lenferink, A., Kraan, Y, Volokhina, E., Vrensen, G., Greve, J., and Otto, C. 2003. Nonresonant confocal Raman imaging of DNA and protein distribution in apop-totic cells. Biophys. J. 84 3968-81. 

It is readily absorbed from the GI tract, 99% bound to plasma proteins, distributed into synovial fluid, the central nervous system, placenta and breast milk. It is metabolised in the liver to glucuronide conjugates, excretion of metabolites is predominantly in the urine with some amount appearing in the faeces. 

Figure 7. Description of the enzyme activity and protein distribution determined in beef extracts cooked to various end-point cooking temperatures (adapted from 2).

The data are also compared (Figure 3) with the 60 min distribution of gallium citrate and the 24 hr distribution of fibrinogen. These data are taken from the literature (16) and represent plasma volume to a first approximation. The cryptate distribution showed no apparent correlation with the protein distributions, as would have been expected if the cryptate had dissociated instantaneously, with subsequent tagging of plasma proteins. 

Figure 13 Map of protein distribution in single wheat starch granules before (left) and after (right) sodium dodecyl sulfate extraction. Granules were scanned after staining with acid fuchsin (from [46]).

The cortical region of many cells is enriched in actin and associated actin-binding proteins, which function in motility, cell shape maintenance, and membrane protein distribution in polarized cells. In some cases, discrete structures anchor actin to the membrane, as is the case for intercellular adherens junctions and cell-substrate focal contacts. In certain special cell types, the fundamental blueprint for an adherens junction is taken to a new structural level, serving as scaffolding for cell-type specific complexes, such as the dystrophin-associated protein complex (DPC) in striated muscle. Although for years morphological studies have described a close association with IF with the actin-rich cortex, recent advances in methods to study protein-protein interactions have provided new insight into the intimate structural and functional relationship between IFs and these membrane domains. 

Wang, X. T., Nagaba, Y., Cross, H. S., Wrba, F., Zhang, L. and Guggino, S. E., 2000, The mRNA of L-type calcium channel elevated in colon cancer protein distribution in normal and cancerous colon. Am J Pathol 157, 1549-62. 

An infrared image study of corn and oat-flour-based extrudates was reported by Cremer and Kaletunc.71 Spatial distributions of starch, protein and lipid were determined. Starch was ubiquitous over the entire cross-section. The protein distribution possessed the smallest degree of uniformity and was inversely correlated with the starch distribution. The lipid distribution was correlated with neither the starch nor the protein distribution. 

The light source. In many cases a rather primitive light source, such as a long automobile lamp is used, but by chance this happens to compensate partially for the uneven distribution of protein on paper (Fig. 30), as the central and darker zone is better illuminated than the lateral zones (P17, S9 Fig. 31). If even illumination of the slit is obtained, this may cause an error analogous to that of a too wide slit whenever there is irregular protein distribution on the strip. 

Fig. 30, Protein distribution in a strip after zone electrophoresis of serum (P16).

Fig. 33. Influence of method of drying on protein distribution, (a) By rapid drying in a hot air stream the protein collects on the surface of the paper and the inner layers remain colorless after staining, (b) Staining after slow drying in room air gives regular distribution through full thickness of paper (El). Magnification X 5.

Pincus JH, Barry K. Protein distribution diet restores motor function in patients with dopa-resistant off period. Neurology 1988 38 481 483. 

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