Protein , aging

Simonson, T. Archontis, G. Karplus, M., Free energy simulations come of age protein-ligand recognition, Acc. Chem. Res. 2002, 35, 430-437... 

Owing to the fact that organic substances have to be separated from a complex sample, transferred to the mass spectrometer target and desorbed, it seems impossible so far to analyse cross-linked binding media from artwork (e.g. dried oil, aged proteins, cross-linked synthetic polymers). Application of classical methods of sample treatment for... 

Correct answer = D. Ubiquitination usually marks old, damaged, or misfolded proteins for destruction by the proteasome. There is no known cellular mechanism for repair of dam aged proteins. 

Section D,5, Fig. 11-8, and Chapter 19). Demethylation occurs by hydrolysis, which is catalyzed by esterases. Carboxylmethylation also occurs in eukaryotic cells but is often substoichiometric and part of a mechanism for repair of isomerized or racemized aspartyl residues in aged proteins (Box 12-A). However, the major eukaryotic protein phosphatase 2A is carboxylmethylated at its C terminus,131 as are the Ras proteins discussed in Section D,3. 

The use of Raman spectroscopy to evaluate the extent of aging in Bruch s membrane as well as the pathogenicity of corresponding protein modifications is an important step toward non-invasive evaluation of the retina. It could serve as a powerful tool for the investigation of the effects of therapeutic drugs designed to prevent or even break established AGE-protein adducts in the aging processes of the human retina [30],... 

T. Araki, Y. Chijiiwa, R. Nagai, N. Araki, and S. Horiuchi, Application of the amino acid analysis for the detection of AGE-proteins of the Maillard reaction, in G, 2002, 391-393. 

F19. Fu, S., Fu, M. X., Baynes, J. W., Thorpe, S. R., and Dean, R. T., Presence of dopa and amino acid hydroperoxides in proteins modified with advanced glycation end products (AGEs) Amino acid oxidation products as a possible source of oxidative stress induced by AGE proteins. Biochem. J. 330, 233-239 (1998). 

D. J. Millward Aging, protein requirements, and protein turnover. American Journal of Clinical Nutrition 66, 774 (1997). 

A severe, atypical headache is usually the first sign, and may herald an impending crisis, which can end in a cerebrovascular accident and death. The hypertensive syndrome is usually characterized by headache, palpitations, flushing, nausea and vomiting, photophobia, and occasionally hyperpyrexia, arrhythmias, and pulmonary edema. Foods with high tyramine content are a major concern. This chemical is a fermentation byproduct. Any food with aged protein should therefore be avoided. 

Keywords Oxidative Stress Free radicals Cell proliferation Aging Protein degradation Apoptosis Growth arrest... 

Daily protein requirements are based on age, nutrition status, disease state, and clinical condition. The RDA for protein for children is shown in Table 135-10, and for individuals over 18 years of age the RDA is 0.8 g/kg per day, which is much less than most people typically consume. In adults older than 60 years of age, protein needs are increased to 1 g/kg per day to help reduce the loss of LBM that occurs with aging, and up to 1.5 to 2 g/kg per day may be needed in states of metabolic stress such as infection, trauma, and surgery. 

Protein methylation reactions can be separated into two major classes. The first class involves methyl ester formation on carboxylic acid groups. These methylation reactions are generally reversible and at least one of their functions is similar to that of protein phosphorylation reactions in switching a modified species from one type of activity to another. However, other types of methyl esterification reactions appear to play more novel roles in the metabolism of aging proteins and in the targeting of proteins to membranes. 

When an oil-soluble emulsifier is present in an oil phase, less proteins (e.g., P-lg and P-casein) are displaced by a water-soluble emulsifier if the emulsion has been aged before the addition of the water-soluble emulsifier (Chen and Dickinson, 1993 Chen et al., 1993). Although the aging time influences the competition of proteins at an interface, protein adsorption is likely to be noncompetitive once one protein has become established at the interface (Dickinson, 1992). The highest surface-active protein would be the major protein at the interface if it is present during emulsification. The protein likely to be predominant in an aged protein film would be the one that was first introduced to the interface, irrespective of whether or not it is the more surface-active of the two proteins. 

MUAMC values can be compared with reference graphs available for both sexes and all ages. Protein-calorie malnutrition and negative nitrogen balance induce muscle wasting and decrease muscle circumference. 

S-allyl mercaptocysteine (SAMC) results from the reaction of allicin with cysteine. It is undetected in whole garlic, but as chopped garlic ages, protein hydrolysis yields cysteine which then reacts with allicin to yield SAMC whose amount increases as chopped garlic ages [37]. 

Experiments in which aged protein film A was exposed to fresh protein B were performed as follows. With a glass tube (ext. diam. 

Elevated levels of isoaspartate residues have been noted within aged proteins. A extracted from parenchyma contains predominantly isoaspartate residues at positions 1 and 7. The aspartic acid residue at position 23 seems largely unaffected, perhaps because of steric protection by the neighbouring valine. It was found that synthetic A with these substitutions resulted in more stable -sheets. These two alterations are found near the beginning and... 

Age Protein [1] Lys [1,8] Lysine/arginine Carnitine [8] Riboflavin Pantothenate ... 

Affmity separation, advantages for protein and peptide separation from biological broths and blood, 297 Aging, proteins, 247-248 Alkylene oxalate polymers, application, 202 Amine-derivatized poly(ethylene terephthal-ate), preparation, 139,141/... 

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