Proteinaceous substances

Removal of Proteinaceous Clouds. With the unchanged method of Averell and Norris (1) the final colored solution of 50.0 ml. may contain as much as 20% ethyl alcohol. Many plant materials, particularly apple pulp, yield proteinaceous substances to the benzene during extraction if the aliquot of extract represents more than 40 to 50 grams of sample, these substances will be present in this final solution as a cloud of solid particles. These substances, whatever their nature, appear to be completely soluble in 60% ethyl alcohol. Thus, the authors recommend the addition of 50 ml. more of ethyl alcohol at this stage, the addition of more hydrochloric acid to maintain pH, and final dilution to 100.0 ml. with water. The resulting solution will be optically clear except for oily or waxy substances, which are removed in the next step. 

The two non-proteinaceous substances f err over din 33) and pyrimine 34) are unique in that they preferentially form ferrous complexes. A number of iron-containing antibiotics have been isolated 35) but of these only a few such as albomycin 36) and ferrimycin 37) have been characterized. 

Comparison of the amino acid profile of unknown samples with amino acid data of reference proteinaceous substances this is a simple and very subjective method [94]. The mean amino acid profile of the three main proteinaceous paint materials is reported in Chapter 1. 

Ho NF, Barshun CL, Burton SP, and Merkle HP (1992) Mechanistic insights to buccal delivery of proteinaceous substances. Adv. Drug Deliv. Rev. 8 197-235. 

Mineral Surfaces. Organic matter is chemically adsorbed (deriva-tized) at the surfaces of clay minerals, zeolites, and related minerals (105) and is at times protected, concentrated, and degraded by contact with the solid surfaces. For example, porphyrins are protected (106), as are optically active amino acids by montmorillonite (107). This may result in part from the position of the organic matter in lattice spaces, as shown by Stevenson and Cheng (108) for proteinaceous substances keyed into hexagonal holes on interlamellar surfaces of expanding lattice clays, or from the fact that there are ordered structures at solid-water interfaces (109). 

Table I summarizes the various meats, meat constituents, and other related substances which have been analyzed, including substances reported on previously (6) as well as those for which new data are given. The substances chosen are intended to provide a cross-section of the type of inherently related material from which volatile irradiation odor and flavor compounds might be expected to form. Thus, in addition to several whole meats, the volatile irradiation products from a number of protein and lipid substances have been analyzed. Among the lipid substances included are typical whole fats and separate moieties such as triglycerides, fatty acid esters, and cholesterol, as an example of a steroid. Among the proteinaceous substances included are a protein, a polypeptide, and some individual amino acids. Finally, beef itself has been separated into a protein, a lipid, and a lipoprotein fraction, and these have been separated, irradiated, and analyzed.

Although the results of the lipid and whole meat studies have been reported (6, 10), a brief review of the findings will help correlate the earlier work with the current studies of proteinaceous substances. 

In meats, of course, there are components which arise from the protein which cannot be present in the products from pure fat. Table III shows some of the sulfur compounds and aromatic compounds which are also found in irradiated meats. Many of these can be postulated as arising from direct bond cleavage of amino acid moieties. Benzene and toluene may come from phenylalanine and phenol and p-cresol from tyrosine. Recent studies have been directed to considering the origin of some of the compounds from proteinaceous substances. Some of the sulfides, disulfides, and mercaptans can derive directly from cysteine or methionine, but those containing more than two carbon atoms in a chain require more than a superficial explanation. In order to evaluate the contribution of the volatiles from the protein as well as the lipid constituents of meat, volatile components produced in various protein substances have also been analyzed. 

Enzymes are proteinaceous substances with highly specific structures that interact with particular substances or classes of substances called substrates. Enzymes act as catalysts to enable biochemical reactions to occur, after which they are regenerated intact to take part in additional reactions. The extremely high specificity with which enzymes interact with substrates results from their lock and key action, based on the unique shapes of enzymes, as illustrated in Figure 3.10. 

In some cases, the nature of the chemical signal is known as well. Larvae of the tube worm Phragmatopoma californica undergo metamorphosis in response to a proteinaceous substance present in the tubes built by conspecific adults.95 Larvae of the sand dollar Dendraster excentricus... 

The hull is mainly composed of flbrous substances, lignin and cellulosic materials in equal proportions. Kernels of oilseed-type sunflower contain nearly all of the oil of seeds, besides proteinaceous substances and carbohydrates. The kernel represents 70% of the seed, with an oil content of approximately 55%, amounting to 40% with respect to the whole seed. The protein content ranges between 20% and 35%, amounting to up to 57% on a water-and-oil-free basis (1, 5, 11). 

Local factors, systemic factors, or a combination of both can cause halitosis. It is estimated that 80%i of all mouth odors are caused by local factors within the oral cavity, and these odors are most often associated with caries, gingivitis, and periodontitis. Oral malodors occur because of the action of various microorganisms on proteinaceous substances, such as, exfoliated oral epithelium, salivary proteins, food debris, and blood.t ]... 

Interlobular capillaries are filled with thick proteinaceous substances that are also deposited below the capillary endothelium and may even be found free in the interstitium. These changes are described as capil-... 

Although interactions between LAB are frequently complicated, many LAB species produce antibacterial proteinaceous substances called bacter-iocins that have a narrow spectrum of activity against closely related species. Many excellent reviews on bacteriocins have been published (De Vuyst and... 

Laccase was first identified by Yoshida [113], as a proteinaceous substance that catalyzed the lacquer curing process and it was first referred to as diastase. Bertrand [114], who had identified one of the defining reactions catalyzed by the enzyme, i.e., the ability to oxidize hydroquinone, implemented the name laccase [115],... 

We will examine in detail enzymes and enzyme inhibitors, enzymes being the proteinaceous substances that catalyze the myriad biochemical reactions or processes that occur in the body. Almost without exception, there is one enzyme specific to each biochemical reaction. (What may be called supporting reactions, side reactions, or simultaneous reactions may also be involved and, in fact, may be a necessity.) In turn, there are other proteinaceous substances, or still other chemical substances, that will inhibit, block, modulate, or control the action of enzymes, and on rare occasion, even accelerate or promote the action. Known as enzyme inhibitors, such substances may affect more than one enzyme, or many different enzymes that is, they may have side effects, or in other words, are nonselective. These inhibitors may be generated internally, or more likely may originate from external sources. That is, they may be designated as medicines. In fact, modem medicine is more and more viewed as encompassing enzymes and enzyme inhibitors. Broadly, this may be viewed as the utilization of biologically active or biochemically active substances, that is, bioactive substances, either natural or synthetic. 

Eaeh and every biochentical reaction in the body is catalyzed or favored by a unique proteinaceous substance called an enzyme, and a sequence of biochemical reactions will require a separate and distinct enzyme for each individual reaction or reaction step. (Moreover, there may be a supporting reaction or reactions involved as well.) Such reaction sequences are commonly called pathways. Some of the reaction steps and corresponding enzymes may be more significant than others, in that they may control the overall conversion rate. In other words, a slower reaction or reactions in the sequence tends to control the overall conversion rate. 

In brief, enzymes are proteinaceous substances that catalyze biochemical reactions, and kinases constimte a subclass of the enzymes classified as transferases, which transfer functional groups. In turn, a kinase can be described as a phosphoryl-transfer enzyme utilizing ATP (adenosine triphosphate) or described as transferring a phosphate group from a nucleoside triphosphate to another molecule, according to the Academic Press Dictionary of Science and Technology. (Examples of some kinases and their actions occur in Figure 3.1 therein.)... 

Interlobular capillaries are filled with thick, proteinaceous substances that are also deposited below the capillary endothelium and may even be found free in the interstitium. These changes are described as capillary sclerosis [68]. Although renal vascular changes in Balkan nephropathy have been pointed out as very important, they are not specific and can be encountered in other renal diseases. Ferluga et al. [70] and Sindjic [77] point out to similarities in early changes encountered in Balkan nephropathy with cyclosporine-induced nephrotoxic changes. 

Hosaku, K. and Maita, Y., 1971. Gas-liquid chromatographic determination of amino acids and vertical distribution of proteinaceous substances in sea water. J. Oceanogr. Soc. Japan, 27 27—33. 

A number of non-proteinaceous substances of plant origin are known that induce or inhibit the sensation of sweetness. Sweetness inducers and enhancers from plants include cynarin, chlorogenic acid, caffeic acid, and arabinogalactin (larch gum) (33). A synthetic compound, 2-(4-methoxyphenoxy)propanoic acid, which is also a constituent of roasted coffee beans, is currently on the market as a sweetness inhibitor (33). Several oleanane-type triterpene esters with sweetness-inhibitory activity occur in Gynmema sylvestre leaves (33,116,117), with dammarane-type saponins with similar effects having been reported recently from the leaves of Hovenia dulcis Thunb. (Rhamnaceae) (118) and Ziziphusjujuba Mill. (Rhamnaceae) (33,119,120). 

A large number of investigations have been described regarding the analysis of the amino acids of whole human hair fibers. Whole-fiber amino acid analysis has several limitations because it provides average values for the amino acid contents of the average proteinaceous substances of the fibers. Therefore, for whole-fiber results, cross-sectional and axial differences in the composition of the fibers are averaged. 

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