Protein scarce

Chem.) sparing substance, protein sparer. Sparren, m. rafter spar, sparsam, a. sparing, economical, close. Sparsamkeit,/. economy parsimony. Sparstoff, m. scarce (or rationed) material, sparstoffarm, a. low in scarce materials. 

It is very difficult and scarce to find literature to study the electrokinetic phenomena of proteins or macromolecules in solution therefore limit us to the basic concepts of electrokinetic changes observed, they are conformational change because of the presence of salts and the zeta potential change in pH. 

In general, microsomes/S9 and cofactor (NADPH or UDPG A) are the most costly components of an incubation, but substrate, especially for early discovery compounds, is sometimes scarce. Higher enzyme concentration will lead to higher volume productivity and less amount of the cofactor to maintain the same cofactor concentration. However, the relationship of reaction rate and enzyme concentration may not be linear, so a higher enzyme concentration may yield lower enzyme productivity (amount of product per milligram enzyme used). Therefore, different protein concentration levels should be screened to obtain a good balance between volume and enzyme productivities. 

Another potential disadvantage of an immunoaffinity separation is the assumed abundance of the purified antigen in sufficient quantities to immobilize on a chromatography support. Protein antigens should be immobilized at densities of at least 2-3 mg/ml of affinity gel to produce supports of acceptable capacity for binding antibody. Often, the antigen is too expensive or scarce to obtain in the amounts needed. 

Where arable land is high cost, high value, or in scarce supply the production potential of protein becomes an especially important factor. Fruits and leaves from wild, undomesticated plants provide attractive sources of protein in the diet because of their natural acceptability by local inhabitants and their wide-spread accessibility due to native growth. However, for domesticated and commercialized situations the production of protein per unit area of arable land is an important factor. 

There is currently much interest in electron transfer processes in metal complexes and biological material (1-16, 35). Experimental data for electron transfer rates over long distances in proteins are scarce, however, and the semi-metheme-rythrin disproportionation system appears to be a rare authentic example of slow electron transfer over distances of about 2.8 nm. Iron site and conformational changes may also attend this process and the tunneling distances from iron-coordinated histidine edges to similar positions in the adjacent irons may be reduced from the 3.0 nm value. The first-order rate constant is some 5-8 orders of magnitude smaller than those for electron transfer involving some heme proteins for which reaction distances of 1.5-2.0 nm appear established (35). 

Relative kidney weight was increased on exposure to the individual compounds at their LONEL and, to about the same extent, on combined exposure at the NONEL or the LONEL/3. The other endpoints studied (histopathology, concentrating abihty, urinary excretion of glucose, protein and marker enzymes, and plasma creatinine and urea) were not or only scarcely affected upon combined exposure at the NONEL or LONEL/3. As assessed by the effect on kidney weight, the renal toxicity of the mixtures corresponded to the effect expected on the basis of the additivity assumption (Feron et al. 1995a, Jonker et al. 1996). 

The actual formation of pyruvic acid from various mercapturic acids upon which these formulae for cysteine and cystine were founded, was only shown later by Baumann s pupils, Konigs, Brenzinger and Schmitz, and in conjunction with Suter s observation that a-thiolactic acid was formed by the hydrolysis of horn, this formula for cystine was accepted. The results obtained, however, scarcely justified this formula as pointed out by Friedmann in 1902, who showed conclusively that the cystine, obtained from proteins, had not this constitution. 

The formation of bromophenylmercapturic acid from bromobenzene and cystine in the organism, if it had the formula given it by Baumann now seemed scarcely possible, unless an isomeric a-thio-y8-aminopropionic acid were also present in the protein molecule together with the di-/8-thio-a-aminopropionic acid or cystine. The investigation of their constitution was therefore taken up by Friedmann in 1904, who succeeded in showing that they were also derived from -thio-a-aminopropionic acid and not from the isomeric a-thio-/8-aminopropionic acid. 

In the field of biopolymer chromatography, monolithic columns, based on copolymerization of silane precursors, have predominately been investigated regarding separation of peptides and complex protein digests, whereas their application to analysis of high-molecules-weight analytes like proteins or dsDNA fragments is scarcely reported. 

Systematic investigations of mannose-binding proteins with clustered mannosides other than natural multiantennary oligosaccharides have been rather scarce until recently. However, using 6 -0-phosphorylated mannose disaccharide scaffolded on peptide templates using combinatorial glycopeptide libraries. 

Applications of reverse proteolysis in the modular assembly of new proteins are rather scarce. This is due to the fact that high-efficiency ligations of two large fragments call for some conformational assistance from prior noncovalent association between them, or some sort of conformational trapping of the product. 

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