Protein component

Vegetable proteins other than that from soy have potential appHcability in food products. Functional characteristics of vegetable protein products are important factors in determining their uses in food products. Concentrates or isolates of proteins from cotton (qv) seed (116), peanuts (117), rape seed (canola) (118,119), sunflower (120), safflower (121), oats (122), lupin (123), okra (124), and com germ (125,126) have been evaluated for functional characteristics, and for utility in protein components of baked products (127), meat products (128), and milk-type beverages (129) (see Dairy substitutes). 

In fine wool such as that obtained from merino sheep, the cuticle is normally one cell thick (20 x 30 x 0.5 mm, approximate dimensions) and usually constitutes about 10% by weight of the total fiber. Sections of cuticle cells show an internal series of laminations (Figs. 1 and 2) comprising outer sulfur-rich bands known as the exocuticle and inner regions of lower sulfur content called the endocuticle (13). On the exposed surface of cuticle cells, a membrane-like proteinaceous band (epicuticle) and a unique hpid component form a hydrophobic resistant barrier (14). These hpid and protein components are the functional moieties of the fiber surface and are important in fiber protection and textile processing (15). 

Protein Components. The simplest picture of the proteinaceous components is one of polypeptides, which are composed of a-amino acid residues. It is estimated that wool contains about 170 different types of polypeptides varying in molecular mass from below 10,000 to greater than 50,000 (34). Complete acid hydrolysis of wool yields 18 amino acids, the relative amounts of which vary considerably from one wool to another. Typical figures for two different samples of wool are given in Table 7. 

Skim milk was initially used as the aqueous phase in margarine. Where the law allows, margarines may contain caseinates, whey proteins, or soy proteins as the proteins component in the aqueous phase. The addition to margarine of 0.01—0.1 wt % sodium caseinate in place of milk has been proposed to eliminate sticking during frying. Substituting soy proteins for milk would have the same effect. 

A method that has been the standard of choice for many years is the Lowry procedure. This method uses Cn ions along with Folin-Ciocalteau reagent, a combination of phosphomolybdic and phosphotnngstic acid complexes that react with Cn. Cn is generated from Cn by readily oxidizable protein components, such as cysteine or the phenols and indoles of tyrosine and tryptophan. Although the precise chemistry of the Lowry method remains uncertain, the Cn reaction with the Folin reagent gives intensely colored products measurable spectrophotometrically. 

In conclusion, the AHR together with inter- and intracellular protein components comprises a very intriguing machinery fliat mediates the induction and regulation... 

The conformation of bovine myelin basic protein (MBP) in AOT/isooctane/water reversed micellar systems was studied by Waks et al. 67). This MBP is an extrinsic water soluble protein which attains an extended conformation in aqueous solution 68 but is more density packed at the membrane surface. The solubilization of MBP in the AOT reversed micelles depends on the water/AOT-ratio w0 68). The maximum of solubilization was observed at a w0-value as low as 5.56. The same value was obtained for another major protein component of myelin, the Folch-Pi proteolipid 69). According to fluorescence emission spectra of MBP, accessibility of the single tryptophane residue seems to be decreased in AOT reversed micelles. From CD-spectra one can conclude that there is a higher conformational rigidity in reversed micelles and a more ordered aqueous environment. 

Benzene dioxygenase is a complex enzyme consisting of three protein components, that catalyse the conversion of benzene to benzene cis-dihydrodiol. Give two reasons why this biotransformation should be carried out using whole cells as opposed to using enzyme preparations. 

Nuclear Receptor Regulation of Hepatic Cytochrome P450 Enzymes. Figure 1 General mechanism for transcriptional activation of CYP genes by xenochemicals that activate their cognate xeno-receptor proteins. In the case of Ah receptor, the receptor s heterodimerization partner is Arnt, whereas in the case of the nuclear receptors CAR, PXR, and PPARa, the heterodimerization partner is RXR. The coactivator and basal transcription factor complexes shown are each comprised of a large number of protein components. 

In general, the receptor-G-proteins complexes exchange bound GDP for GTP. In turn, the two, smaller subunits of the G-protein components of these complexes are released and the receptor protein dissociates. The remaining G-protein GTP complex then complexes with and activates a specific enzyme. It is very significant to note that G-proteins therefore have at least three specific binding sites (a) for nucleotides, (b) for a receptor protein, and (c) an effector protein. 

This is not to say that other effects are not also operating. The production of methane by ruminants, discussed in Section 3.2, is one additional influence which would have a similar effect on the spacing, as is apparent by modifying the d term in equation V from +10 to +13%o. But this approach should enable field data to be interpreted in a unified and simple form. Note the strong emphasis it places on the effects of the values both of the protein and non-protein components on the spacing. It also allows predictions to be made of the spacing in unusual situations, for example, where the protein may be isotopically lighter than the non-protein. 

GA is well recognized as emulsifier used in essential oil and flavor industries. Randall et al., 1998, reported that the AGP complex is the main component responsible for GA ability to stabilize emulsions, by the association of the AGP amphiphilic protein component with the surface of oil droplets, while the hydrophilic carbohydrate fraction is oriented toward the aqueous phase, preventing aggregation of the droplets by electrostatic repulsion. However, only 1-2% of the gum is absorbed into the oil-water interface and participates in the emulsification thus, over 12% of GA content is required to stabilize emulsions with 20%... 

It is well known the tendency of polysaccharides to associate in aqueous solution. These molecular associations can deeply affect their function in a particular application due to their influence on molecular weight, shape and size, which determines how molecules interact with other molecules and water. There are several factors such as hydrogen bonding, hydrophobic association, an association mediated by ions, electrostatic interactions, which depend on the concentration and the presence of protein components that affect the ability to form supramolecular complexes. 

Collagen is the major protein component of coimective tissue and constitutes approximately 25% of the total protein content in humans. There are more than 19... 

Mutations that result in antibiotic resistance at the level of protein synthesis are more often found in rRNA than in the protein components of the ribosome. 

LAMININ IS A MAJOR PROTEIN COMPONENT OF RENAL GLOMERULAR OTHER BASAL LAMINAS... 

Figure 49-3. Schematic representation of the thin fiiament, showing the spatiai configuration of its three major protein components actin, myosin, and tropomyosin. The upper panei shows individual molecules of G-actin. The middle panel shows actin monomers assembled into F-actin. Individual molecules of tropomyosin (two strands wound around one another) and of troponin (made up of its three subunits) are also shown. The lower panel shows the assembled thin filament, consisting of F-actin, tropomyosin, and the three subunits of troponin (TpC, Tpl, andTpT).

There are receptors (TfRs) on the surfaces of many cells for transferrin, it binds to these receptors and is internalized by receptor-mediated endocytosis (compare the fate of LDL Chapter 25). The acid pH inside the lysosome causes the iron to dissociate from the protein. The dissociated iron leaves the endosome via DMTl to enter the cytoplasm. Unlike the protein component of LDL, apoTf is not degraded within the lysosome. Instead, it remains associated with its receptor, returns to the plasma membrane, dissociates from its receptor, reenters the plasma, picks up more iron, and again delivers the iron to needy ceils. 

Miller and Macmillan [4] carried out purification of pectinesterase from Fusarium oxysporum f. sp. vasinfectum culture fluid (fivefold degree of purification). According to the obtained data the purified enzyme possessed very low polygalacturonatlyase one. Disk electrophoresis at pH 4.3 revealed two protein components. The authors did not study distribution of pectinesterase activity in these components. Molecular weight of fungal pectinesterase determined using gel — filtration on Sefadex G — 75 was found to be 35,000. 

Ullah AJH, R1 Murray, PK Bhattacharyya, GC Wagner, IC Gunsalus (1990) Protein components of a cytochrome P-450 linalool 8-methyl hydroxylase. J Biol Chem 265 1345-1351. 

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