N-Asparagine

Figure 2.9. Amino acid sequences of human defensins. The conserved positions of six cysteine residues are shown in hatched boxes. Abbreviations A, alanine C, cysteine D, aspartic acid E, glutamic acid F, phenylalanine G, glycine H, histidine I, isoleucine K, lysine L, leucine M, methionine N, asparagine P, proline Q, glutamic acid R, arginine S, serine T, threonine V, valine W, tryptophan Y, tyrosine.

Fic. 1. The amino acid sequences of calf histones H2A (Yeoman et al., 1972 Sau-tiere et al., 1974) and H2B (Iwai et al., 1972). A one-letter code is used A, alanine R, arginine N, asparagine D, aspartic acid C, cysteine E, glutamic acid Q, glutamine ... 

Amino acid side chains at the positions X, Y, Z, -Y,-X, and —Z (illustrated in Fig. 29) of EF hands and other calcium-binding regions are listed. D, Aspartic acid E, glutamic acid N, asparagine S, serine T, threonine Ox, main-chain carbonyl Wa, water Ph, phosphate O -, a number of intervening amino acids. 

Figure 6.8 Experimental variation of the retention of 23 phenylthiohydantoin (PTH) derivatives of amino acids with mobile phase composition in RPLC. Mobile phase mixtures of acetonitrile and 0.05M aqueous sodium nitrate buffer (pH — 5.81). All mobile phases contain 3% THF. Stationary phase ODS silica. Solutes D = aspartic acid C-OH = cysteic acid E = glutamic acid N = asparagine S = serine T = threonine G = glycine H = histidine Q = glutamine R = arginine A = alanine METS = methionine sulphone ABA = a-aminobutyric acid Y = tyrosine P = proline V = valine M = methionine NV = norvaline I = isoleucine F = phenylalanine L = leucine W = tryptophan K = lysine. Figure taken from ref. [610]. Reprinted with permission.

FIGURE 10.19 Deduced amino acid sequence for fructan fructan transferase (FFT) and sucrose sucrose 1-fructosyltransferase (SST). (From van der Meer, I.M. et al., Plant /., 15, 489-500, 1998.) Amino acids in bold represent homology between FFT and SST. Symbols A = alanine C = cysteine D = aspartate E = glutamate F = phenylalanine G = glycine H = histidine I = isoleucine K = lysine L = leucine M = methionine N = asparagine P = proline Q = glutamine R = arginine S = serine T = threonine V = valine W = tryptophan and Y = tyrosine. 

S. Takasaki, G. J. Murray, F. S. Furbish, R. O. Brady, J. A. Barranger, and A. Kobata. Structure of the N-asparagine-like oligosaccharide units of human placental p-glucocerebrosidase. J. Biol. Chem. 259 10112 (1984). 

A— alanine, C—cysteine, D— aspartate, E— glutamate, F— phenylalanine, G-— glycine, H—histidine, I—isoleucine, K—lysine, L—leucine, M—methionine, N—asparagine, P—proline, Q—glutamine, R—arginine, S—serine, T—threonine, V—valine, W— tryptophan, Y—tyrosine. 

Table 15.2. Structural families in the basic loop structures. CONFORMATION is the conformation of the loop (0, ((/ angles, see caption of Figure 15.5) NO. is number observed in proteins analyzed SEQUENCE is the sequence template a,, T are used to denote residues favoring a helix, P strand and type I P turn structures respectively i = polar, = hydrophobic - is any amino acid capital letters are one letter amino acid code (G Glycine D Aspartic Acid, N Asparagine, S Serine, T threonine, A Alanine, H Histidine, P Proline) / indicates alternative, blank indicates loop limits...

Higher yields of L-[amide- N]asparagine have been obtained by a rapid, nonenzymatic method. The free -carboxyl group of L-a-N-f-Boc-a-t-Bu-aspartic acid is activated with N-hydroxysuccinimide to yield L-a-N-f-Boc-a-t-Bu- -N-hydroxysuccinimidyl aspartic ester, which is re-fiuxed for 10 min with [ N]anunonia. Hydrolysis for 1 min in IN HCl yields up to 30-40% of L-[ami fe- N]asparagine, which is then purified by cation-exchange column chromatography (31). 

Fig. 11.2.11. Isocratic separation of PTH-amino adds. Chromatographic conditions column, Ultrasphere ODS (250 X 4.6 mm I.D.) mobile phase, 0.01 M sodium acetate (pH 4.9)-acetonitrile (62.2 37.8) flow rate, 1 ml/min temperature, ambient. Peak identity corresponding to the single letter code for amino acids D, aspartic acid E, glutamic acid N, asparagine Q, glutamine T, threonine G, glycine A, alanine Y, tyrosine M, methionine V, valine P, proline W, tryptophan F, phenylalanine K, lysine I, isoleucine L, leucine S, serine. Reproduced from Noyes (1983), with...

Amino acid abbreviations A=Arginine D=Aspartie aeid E=Glutamate F = Phenylalanine G = Glyeine H = Histidine I = Isoleucine K = Lysine L = Leucine N = Asparagine P=Proline Q = glutamine R=Arginine S=Serine T=Threonine ... 

Letters indicate single letter code for amino acids as follows A = Alanine, F = Phenylalanine, G = Glycine, I = Isoleucine, K=Lysine, N =Asparagine, P = Proline, Q = Glutamine, R=Arginine, S = Serine, T=Tlireonine W=Tryptophan, X = any amino acid and Y = Tyrosine. 

Data are taken from [59,60]. Single letter codes for amino acids are used as Table 4 and as follows T, threonine Q, glutamine S, serine V, valine L, leucine N, asparagine. Tba and Ac are abbreviations for t-butylacetic acid and acetyl, respectively. 

Two asparaginases have been demonstrated in Brucella abortus (strain 19) (267). One is specific for the n-isomer and the other for the L-isomer of asparagine. Both appear to be sulfhydryl enzymes. Extracts of Myco-baeterium phlei and Mycobacterium tuberculosis (B.C.G.) catalyze the hydrolysis of L-asparagine with only slight activity toward glutamine 268). n-Asparagine inhibits competitively the L-asparaginase activity of M. phlei 269). 

An early analysis of the spleen enzyme showed the presence of hexose and hexo-samine A more recent study has demonstrated an enzyme from human hairy leukemic cells which appears identical to the purple spleen phosphatase, and which binds to ConA-Sepharose and is eluted with methylmannoside Very likely, therefore, the spleen enzyme, Uke uteroferrin, is a high mannose glycoprotein, but the structure of its carbohydrate has yet to be determined. In each protein the oligosaccharide chain appears to be attached to an asparagine residue (at position 97 in uteroferrin), since this residue was observable only after treatment with N-glycanase which removes N-asparagine-linked oUgosaccharides. ... 

K, lysine L, leucine N, asparagine P, proline Q, glutamine R, arginine S, serine T, threonine ... 

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