Amino acid side chains hydroxyl-containing

Protein kinases phosphorylate proteins only at certain hydroxyl groups on amino acid side chains. Which of the following groups of amino acids all contain side chain hydroxyl groups ... 

Hydroxyl radical oxidative modification, one of the footprinting approaches, utilizes hydroxyl radicals to oxidize certain amino acid side chains followed by extent of modification measurement by MS. For example, fast photochemical oxidation of proteins (FPOP) [35] involves irradiation of protein sample solutions containing hydrogen peroxide by a KrF excimer laser and generation of hydroxyl radicals in the solution. FPOP occurs on the microsecond timescale for the labeling... 

Amino acids with side chains that contain an amide group (asparagine and glutamine) or a hydroxyl group (serine and threonine) can be classified as aliphatic, polar, uncharged amino acids. Asparagine and glutamine are amides of the amino... 

The structures of the amino acids are given in Figure 21.2. A side chain is nonpolar if it is mostly hydrocarbon in nature (like alanine). Polar side chains may contain the hydroxyl group (—OH), the sulfhydryl group (—SH), or a second amino (—NH3) or carboxyl (—COOH) group. 

Of the 20 protein-derived amino acids shown in Table 18.1, how many contain (a) aromatic rings, (b) side-chain hydroxyl groups, (c) phenolic —OH groups, and (d) sulfur ... 

All natural product members of the echinocandin class have a cyclic hexapeptide ring with a fatty acid side chain attached to the a-amino-group of the ornithine. All members contain an unusual, hydroxyl-substituted, homotyrosine residue, two substi-... 

Several of the amino acids have side chains that contain functional groups such as hydroxyl —OH, amide —CONH2, amine —NH2, which is ionized as ammonium —NH3, and carboxyl —COOH, which is ionized as carboxylate —C00 . 

Nitrogen-containing side chains in amino acids can be altered by oxidation forming chloramines or even become deaminated. The result is often the formation of carbonyls (e.g., aldehydes) and hydroxyls. Lee, S et al. (2006) found that Fe-EDTA-mediated oxidation of human... 

Replacement of the hydroxyl group on the phenyl ring with a carboxyl group forms a molecule of benzoic acid. Addition of a hydroxyl at the 2-position on a benzoic acid molecule forms 2-hydroxybenzoic acid or salicylic acid. The slightly more complex phenylpropanoid skeleton contains a linear three-carbon chain (the propanoic group) added to the benzene ring (the phenyl group). Addition of ammonia to carbon 2 of this three-carbon side chain yields the amino acid phenylalanine (Fig. 3.3). Phenylalanine... 

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