Tryptophanyl-alanine

Glycyl glutamic acid Glycyl proline Glycyl tryptophan Leucyl glycyl phenylalanine Tryptophanyl alanine Tryptophanyl glycine Tryptophanyl tryptophan Tryptophanyl tyrosine... 

L-Tryptophanyl-L-methionyl-L-aspartyl-L-phenylalanine amide trifluoroacetate N-t-Butyloxycerbonyl- -alanine 2,4,5-trichlorophenyl ester... 

A solution of 3.55 parts of L-trypTtophanyl-L-methionyl-L-aspartyl-L-phenylalanine amide trifluoroacetate in 30 parts of dimethylformamide is cooled to 0 C, and 1.01 parts of tri-ethylamine are added. The mixture is stirred while 1.84 parts of N-tert-butyloxycarbonyl-(3-alanine 2,4,5-trichlorophenyl ester are added at 0 C. The reaction mixture is kept at 0°C for 48 hours and then at 20°-23°C for 24 hours. The mixture is added to a mixture of 100 parts of ice-water, 0.37 part of concentrated hydrochloric acid (SG 1.18), 1.2 parts of acetic acid and 20 parts of ethyl acetate. The mixture is stirred for 15 minutes at 0°-10°C and is then filtered. The solid residue is washed with water and then with ethyl acetate, and is dried at 40°-50°C under reduced pressure. There is thus obtained N-tert-butyloxycarbonyl-)3-alanyl-L-tryptophanyl-L-methionyl-L-aspartyl-L-phenylalanine amide, MP 213°C with decomposition. 

L-alanylglycyl-L-cysteinyl-L-lysyl-L-asparaginyl-L-phenylalanyl-L-phenylalanyl-L-tryptophanyl-L-lysyl-L-threonyl-L-threonyl-L-cysteine 6-0-benzoyl-N-(benzyloxycarbonyl) methylamide 4,6-0-benzylidene-N-benzylidene-N-(benzyloxycarbonyl) methylamide N- (benzyloxy carbonyl) -N-(benzyloxycarbonyl)-, amide N-(benzyloxycarbonyl)-, hydrazide N-(benzyloxycarbonyl)-, methylamide N-(benzyloxycarbonyl)-, methyl ester N-(benzyloxycarbonyl)-L-alanyl-L-alanine methyl ester N-(benzyloxycarbonyl)-L-alanylglycine ethyl ester N-(benzyloxycarbonyl)glycyl-L-alanine methyl ester 3,4,6-tri-0-acetyl-2-amino-2-deoxy-N-(benzyloxycarbonyl)-, benzyl ester, hydrochloride... 

The 37-kDa 334-residue subunits of the dimeric type I tryptophanyl-tRNA synthetase238 are the smallest known the largest bacterial synthetase is an alanine-specific type II tetramer with 95-kDa 875-residue subunits.239 Gene deletions show that a much smaller core, comparable in size to that of the tryptophanyl-tRNA synthetase, is needed for amino acid activation. The synthetases share little sequence homology except for a short 11-residue part of the adenylate binding site near the N terminus.240 241 Some of the synthetases contain bound zinc ions.225,242... 

Cleavage of terminal tyrosyl and tryptophanyl peptides. L-Tyrosyl-L-alanine (1) and related dipeptides are cleaved by 01 1(0Ac)2 in CH3OH containing KOH to 4-(methoxymethyl)phenol (2) and an amino acid. Under the same conditions, L-tyrosine yields (4-hydroxyphenyl)acetonitrile, HOC6H4CH2CN. The phenolic hydroxyl group and the free amino group are essential for this cleavage.1... 

Secondly, fluorescence emission spectra of proteins usually allow conclusions to be drawn about the environment of the main fluorescent groups present (mainly the L-tryptophanyl residues). Fluorescence, in addition to circular dichroism, indicated that L-tryptophanyl residues in carboxypeptidase Y were buried in an apolar unsymmetrical environment (c.d. also indicated 40% / -conformation). Similarly in L-alanine aminopeptidase and dihydrofolate reductase fluorescence suggested L-tryptophanyl residues located in hydrophobic surroundings. By contrast, in bacteriorhodopsin one or more Trp residues appear to be exposed to a polar medium. ... 

Tryptophan peptides. Triethylamine added to a soln. of benzyl L-alaninate hydrochloride in methylene chloride, mixed at 0° with a soln. of carbobenzoxy-L-tryptophan in the same solvent, dicyclohexylcarbodiimide added, and stirred overnight at room temp. benzyl carbobenzoxy-L-tryptophanyl-L-alaninate. Y 80%. F.e. s. M. Wilchek and A. Patchornik, J. Org. Ghem. 28, 1874 (1963) glycopeptides in pyridine cf. S. M. Amir, J. S. Brimacombe, and M. Stacey, Nature 203, 401 (1964),... 

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