Caries protein

Actinia cari. When an extract of the tentacles of this species was subjected to gel nitration, a single protein peak having hemolytic and lethal activities was obtained. Further fractionation by CM-cellulose ion-exchange chromatography yielded three well separated peaks (CTl, Cmi, Cmil) which appeared to be similar in biological activity (14). 

The most widely studied therapeutic proteins produced in plants include monoclonal antibodies for passive immunotherapy and antigens for use as oral vaccines [40]. Antibodies against dental caries, rheumatoid arthritis, cholera, E. coli diarrhea, malaria, certain cancers, Norwalk virus, HIV, rhinovirus, influenza, hepatitis B virus and herpes simplex virus have been produced in transgenic plants. However, the anti-Streptococcus mutans secretory antibody for the prevention of dental caries is the only plant-derived antibody currently in Phase II clinical trials [40]. Until recently, most antibodies were expressed in tobacco, potato, alfalfa, soybean, rice and wheat [9], It has been estimated that for every 170 tons of harvested tobacco, 100 tons represents harvested leaves. A single hectare could thus yield 50 kg of secretory IgA [3, 41]. Furthermore, it has been estimated that the cost of antibody production in plants is half that in transgenic animals and 20 times lower than in mammalian cell cul-... 

The first NIR instruments were, in reality, developed for the UV and Vis regions of the spectrum. They were made by seven companies Beckman, Cary (now owned by Varian), Coleman, Perkin-Elmer, Shimadzu, Unicam, and Zeiss. Based on the work of Karl Norris and coworkers in the USDA, the Illinois Department of Agriculture solicited bids from companies to produce a pure NIR instrument, capable of measuring protein, oil, and moisture in soybeans. 

Cytochrome Determinations. Microsomal suspensions (1-5 mg protein/ ml) were assayed for cytochromes bs and P-A50 (12) using a Cary 15 spectrophotometer operated at room temperature (20-23°C). Suspensions in 0.05M phosphate buffer, pH 7.A, were contained in 3 ml cuvettes with a 1 cm path length. Sodium dithlo-nite was the reductant. The extinction coefficient of 171 mM 1 cm 1 was applied to the A28-A90 nm absorbance increment. 

An excess of zinc will cause problems in humans. Excessive doses can lead to biochemical control system damage, while doses slightly higher than optimal can cause disorders in iron and copper metabolism, resulting in incurable anemia, decrease in activity of zinc protein enzymes, and pancreas and kidney damage (Boularbah et ah, 1999 Seiler et ah, 1994). Increased levels of zinc have been observed in nuclei of neoplastic cells and in cases of acute dental caries, however its role in these diseases has not been explained. 

The design of safe sweeteners is very important for people who are afiected by diabetes, hyperlipemia, caries and other diseases that are linked to sugar consumption. Sweet proteins, which are found in several tropical plants, are many times (100-100,000) sweeter than sucrose on a molar basis. Only a few sweet proteins are known miraculin, monellin, thaumatin, curculin, mabinlin. 

The initial products of the reactions between sugars and proteins may enter a cascade of reactions yielding fluorescence, browning, and polymerization of proteins ("cross-linking"). The brown pigments, so-called melanoidins, are polymers whose composition has not yet been established completely. Melanoidins bind calcium and may thus interfere with de- and remineralization in caries. 

In the present investigation we sought to clarify the purported relation between dentin caries and matrix protein modifications such as the Maillard reaction and cross-linking. 

From the literature reviewed in Chapter 3, it can be concluded that the Maillard reaction between carbohydrates and proteins is the likely cause of the discoloration of caries lesions. Research in the following chapters focused on this reaction. 

Chapter 4 describes the in vitro reaction of glucose wifh demineralized dentin. Preliminary tests revealed that use of disfilled insfead of deionized water accelerated browning, consistent with the effect of frace metals on the Maillard reaction. The yellow discolored slices were more resistant than controls to pepsin-mediated breakdown, but not to trypsin-mediated breakdown. It would be worthwhile to investigate proteolysis of denfin collagen covalently bound by the Maillard reaction to proteins, which penetrate into a caries lesion. 

Aside from the Maillard reaction, other covalent modifications of amino acids and proteins are possible within the caries lesion, which merit future investigation. For example, certain oral microorganisms excrete y-glutamyl transferases. These enzymes catalyse the formation of cross-links between glutamic acid and lysine residues of proteins. In addition, N-acyl amino acids are present in plaque, which adsorb to mineral surfaces. 

Figure 1. Top Turbidity, measured at 350 nm, as a function of microtubule polymer mass concentration (expressed as mg/mL polymerized tubulin). Tubulin solutions of varying concentrations were polymerized until they reached stable plateau values in a Cary 118C spectrophotometer. Each sample was then transferred to an ultracentrifuge tube, and microtubules were pelleted, separated from the unpolymerized tubulin in the supernatant fraction, and then resuspended for protein concentration determination. The corresponding turbidity and polymer mass concentrations are plotted here. Bottom Time-course of tubulin polymerization assayed by turbidity.Repro-duced from MacNeal and Purich with permission from the American Society for Biochemistry and Molecular Biology.

T. Tanabe, T. Aoba, E.C. Moreno, M. Fukae, Effect of fluoride in the apatitic lattice on adsorption of enamel proteins onto calcium apatites, J. Dent. Res. 67 (1988) 536-542. C. Robinson, S. Connell, J. Kirkham, S.J. Brookes, R.C. Shore, A.M. Smith, The effect of fluoride on the developing tooth. Caries Res. 38 (2004) 268-276. 

A. van Nieuw Amerongen, J.G.M. Bolscher, E.C.I. Veerman, Saliva proteins Protective and diagnostic value in cariology. Caries Res. 38 (2004) 247-253. 

There is no direct evidence that the consumption of simple sugars is harmful. Contrary to folklore, diets high in sucrose do not lead to diabetes or hypoglycemia. Also contrary to popular belief, carbohydrates are not inherently fattening. They yield 4 kcal/g (the same as protein and less than half that of fat, see Figure 27.5), and result in fat synthesis only when consumed in excess of the body s energy needs. However, there is an association between sucrose consumption and dental caries, particularly in the absence of fluoride treatment. 

His1 0 and orients it for its catalytic function [54], The putative catalytic thiolate-imldazollum pair at the active site of bromelain is thus, by comparison of the amino acid sequence of bromelain with other cysteine protein ases, likely to have a different conformation from that in (he cysteine proteinases (hat aie tightly inhibited by cystatin [45]. Bromelain also distinguishes itself from other cysteine protein ases by its slow inhibition by the irreversible inhibitor of cysteine oroteinases E-64 rW-ft 3-fraw-cari)OKVOxiran-2 BrboiwlVL-leucvn-amido 4-... 

Reynolds, E.C. and Del Rio, A. 1984. Effect of casein and whey protein solutions on the caries experience and feeding patterns of the rat. Arch. Oral Biol. 29, 927-933. 

The basic amino acids of serum proteins. III. A chemical relationship between serum proteins of various origins. Ibid., 104, 347 (1934). With D. C. Darrow and M. K. Cary. 

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