Cyclic Amino Acids - Aromatic Amino Acids, Phenylalanine, Tryptophan, Tyrosine, Proline, Hydroxyproline, Pseudoproline (Paperback)

Purchase includes free access to book updates online and a free trial membership in the publisher's book club where you can select from more than a million books without charge. Chapters: Aromatic Amino Acids, Phenylalanine, Tryptophan, Tyrosine, Proline, Hydroxyproline, Pseudoproline, Azetidine-2-Carboxylic Acid, 1-Aminocyclopropane-1-Carboxylic Acid, D-Dopa. Excerpt: 11.4 g/L at 25 C,17.1 g/L at 50 C,27.95 g/L at 75 C Tryptophan (IUPAiIUBMB abbreviation: Trp or W; IUPAC abbreviation: L-Trp or D-Trp; sold for medical use as Tryptan) is one of the 20 standard amino acids, as well as an essential amino acid in the human diet. It is encoded in the standard genetic code as the codon UGG. Only the L-stereoisomer of tryptophan is used in structural or enzyme proteins, but the D-stereoisomer is occasionally found in naturally produced peptides (for example, the marine venom peptide contryphan). The distinguishing structural characteristic of tryptophan is that it contains an indole functional group. It is an essential amino acid as defined by its growth effects on rats. The isolation of tryptophan was first reported by Frederick Hopkins in 1901 through hydrolysis of casein. From 600 grams of crude casein one obtains 4-8 grams of tryptophan. Plants and microorganisms commonly synthesize tryptophan from shikimic acid or anthranilate. The latter condenses with phosphoribosylpyrophosphate (PRPP), generating pyrophosphate as a by-product. After ring opening of the ribose moiety and following reductive decarboxylation, indole-3-glycerinephosphate is produced, which in turn is transformed into indole. In the last step, tryptophan synthase catalyzes the formation of tryptophan from indole and the amino acid serine. The industrial production of tryptophan is also biosynthetic and is based on the fermentation of serine and indole using either wild-type or genetically modified bacteria such as Corynebacterium glutamicum, Bacillus subtilis,... More: http://booksllc.net/?id=58358