Native physicochemical properties

Milk is biochemically well characterized, and the physicochemical properties of the major native milk proteins of various species are well known. This helps rational development of appropriate downstream processing protocols (Table 5.8). 

The use of HPLC to analyze biogenic amines and their acid metabolites is well documented. HPLC assays for classical biogenic amines such as norepinephrine (NE), epinephrine (E), dopamine (DA), and 5-hydroxytryptamine (5-HT, serotonin) and their acid metabolites are based on several physicochemical properties that include a catechol moiety (aryl 1,2-dihydroxy), basicity, easily oxidized nature, and/or native fluorescence characteristics (Anderson, 1985). Based on these characteristics, various types of detector systems can be employed to assay low concentrations of these analytes in various matrices such as plasma, urine, cerebrospinal fluid (CSE), tissue, and dialysate. 

Bioactive sequences of up to six amino acid residues known to assume (1- or "/-turns in the bioactive conformation are suitable for such libraries. If the sequence is short, residues have to be added in a manner to retain the desired physicochemical properties of the peptide (e.g., to short polar active sequences hydrophobic residues are preferentially added and vice versa). The choice of the scaffold depends on the number of structure-inducing amino acids such as Gly or Pro present in the native sequence. In absence of such residues scaffolds (1) or (4) (Scheme 24) are selected, whereas if Gly or Pro is present alternative scaffolds can be considered. Then the components of the four stereoisomeric sublibraries of Scheme 26 (or their equivalents if other scaffolds are chosen) are synthesized according to procedures described in the preceding sections. 

Figure 19.2 shows the different physicochemical properties of the PES membranes modified with RGD and galadose moiety with resped to the collagen that was used as a natural substrate. Native PES membranes have a very high hydrophilic surface charader, in fad, the water contad angle measured on this membrane was 30 1.4°. Also, the modified membranes display a marked wettability even if, in this case, the... 

Konrad, G., Lieske, B., and Faber, W. 2000. A large-scale isolation of native (3-lactoglobulin characterization of physicochemical properties and comparison with other methods. Int. Dairy J. 

The aim of this contribution is to present experimental data concerning the synthesis, physicochemical properties and bio-activity of several nanosilica-based composites tested by interaction with native red blood cells (RBCs). The investigations include (i) synthesis of nanocomposites by adsorption of BSA, fructose and glucose on a fumed silica surface, and (ii) analysis of the adsorption properties of composites and their bio-activity. It is known that both glucose and fructose do not individually adsorb on fumed silica therefore, bovine serum albumin was used as a mediator to bind the monosaccharides to the fumed silica surface. 

It appears that crystallography is able to provide at least partial answers to these questions. Two very interesting new results indicate that the so-called native, or inactive, molecule may be far less stable than has been inferred from the original crystal structures, and that the physicochemical properties of the solution (e.g., ionic strength, pH) may significantly destabilize the lid. 

PRL has also been selectively cleaved by limited proteolysis with fibrinolysin (50). This results in the cleavage of the peptide chain between residues 53 and 54. The two fragments PRL(1-53) and PRL(54-199) are devoid of both lactogenic activity and immunoreactivity. Recombination of the fragments resulted in full restoration of immunoreactivity but not biological activity. The physicochemical properties of the recombinant molecule were very similar but not identical to those of the native hormone. These results emphasize the enormous importance of the integrity of the conformation of these hormones for their biological funct ions. 

Physicochemical properties of P-galactosidase Native BGase, a tetramer, has a molecular weight of 465000 (from its complete amino acid sequence) and a pi of 4.6 (Fowler and Zabin, 1977). The tetramer dissociates into inactive monomers at pH <3.5 or >11.5 or with mercurials (Loontiens et al., 1970). Aggregated... 

Guanylate cyclase [GTP pyrophosphate-lyase (cyclizing) EC 4.6.1.2.] can be purified as soluble and particulate isozyme forms from most mammalian tissues. While both isozyme families catalyze the formation of cGMP from GTP, they are structurally different proteins. Their mechanism of activation and their kinetic and physicochemical properties differ markedly from each other. Soluble guanylate cyclase (sGC) has been shown to exist as a heterodimer with protein subunits of 70 and 82 kDa and has a native... 

The specific sequence of amino acids in a protein determines its structure, conformation, and physicochemical properties. The structure of protein is categorized as primary, secondary, tertiary, or quaternary, depending on the progressive state of spatial arrangement of polypeptide chains of the protein (1,2). Although the primary structures of almost all major food proteins are known, the exact conformation of only a few native proteins e.g. 9-lactoglobulin has been elucidated (3-5). 

Distinct differences are noted in several physicochemical properties of floe and soils of WCA-1, WCA-2, WCA-3, and ENP (Tables 17.4-17.7). Spatial patterns of total phosphorus in WCA-1, WCA-2A, WCA-3, and ENP showed higher total soil phosphorus in areas closer to inflow structures (predominantly cattail vegetation) than the interior areas with native saw grass vegetations... 

Immobilization is, as a rule, accompanied by a declining activity of the enzymes. However, at present there are numerous examples of successful immobilization with the preservation of enzyme specificity and activity within 10 to 90% of its activity in the native state. This permits us to think that the problem of obtaining enzymic preparations which are close in physicochemical properties to heterogeneous catalysts and electrocatalysts, particularly as regards the preservation of enzymatic activity and specificity, can be successfully solved in each specific case. 

Griffin PJ, Fogarty WM Physicochemical properties of native, zinc-prepared and manganese-prepared metalloprotease of Bacillus polymyxa. Appl Microbiol 1973,260) 191-195. 

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