N -Acetyl-L-lysine

L-lysine (N-acetyl-L-lysine) Brevibacterium ketoglutamicum Nocardia sp. hom 75... 

Material and Supplies Milk-crumb and soya-crumb were prepared by the KANOLD AB Co., Goteborg, Sweden. N-((-acetyl-L-lysine. A Grade, Calbiochem. 

PM Hardy, AC Nicholls, HN Rydon. Nature of cross-linking of proteins by glutaral-dehyde. 1. Interaction of glutaraldehyde with amino groups of 6-aminohexanoic acid and of a-N-acetyl-L-lysine. J Chem Soc, Perkin Trans I 958-962, 1976. 

The rate of nucleophile addition to the double bond is dependent on the nature of the nucleophile as would be expected. Finley et al. (47) have measured the relative effectiveness of the sulfhydryl group of L-cysteine and the e-amino group of a-N-acetyl-L-lysine in adding to the double bond of N-acetyl dehydroalanine. At equal concentrations of the reactive species, cysteine adds some 31 times more rapidly to the double bond than does a-N-acetyl-L-lysine (47). However, when one compares these two compounds at the same pH the relative rates in favor of cysteine (pK of sulfhydryl group = 8.15) versus a-N-acetyl-L-lysine (pK of e-amino group = 10.53) are most impressive at lower pH s (Table VI). Therefore, it has been recommended that cys-... 

Table VI. Relative Rates of Addition of the Sulfhydryl Group of Cysteine and the e-Amino Group of a-N-Acetyl-L-Lysine to the...

N-Acetylation of basic amino acids. The reagent reacts with an aqueous solution of the copper salt of a basic amino acid to give the N-acetyl derivative.1 The procedure is superior to the usual synthesis in which acetic anhydride is used because the reaction goes to completion. As applied to L-lysine, the method is simple and gives better yields of pure e-N-acetyl-L-lysine. Excess cupric carbonate is added to a boiling aqueous solution of L-lysine (0.1 mole) and the solution is filtered and cooled to 25° and treated with sodium bicarbonate, p-nitrophenylacetate, and a few milliliters of ethyl acetate to keep the acetate in solution. After stirring for 15 hrs the copper salt which separates is filtered, suspended in water, and freed of copper with H2S. The solution is evaporated to dryness and the N-acetyllysine crystallized from water-ethanol. 

XLVIII N -Acetyl-L-lysine sugar beet Beta vulgaris Chenopodiaceae... 

The kinetics of the addition of IV-acetyl-L-cysteine, N-acetylcysteamine, and N2-acetyl-L-lysine (NAL) to / -methoxycinnamate, / -methoxycinnamide, anthranilate, and crotonyl or sorboyl thiol ester have been studied, and the thiol addition products identified. The reaction rates increased at higher pH and the crotyl thiol ester was found to be 7.9 times more reactive than a sorboyl thiol ester toward IV-acetyl-L-cysteine addition. These unsaturated thiol esters may serve as a means of covalently binding UVA and UVB sunscreens to the outer layer of skin to provide long-lasting protection.128... 

About 95% of the lAA within plants is stored as conjugated forms that include amides with various amine acids and peptides and glycosyl deriva-tives. " The gall-forming Pseudomonas savastonoi forms both lAA and conjugates such as N -(indole-3-acetyl)-L-lysine, which aid these bacteria in colonizing olive and oleander plants. ... 

Ac-c-IAA-Lys P. s. savastanoi C gH23N305 N-a -Acetyl-N-e-(indole-3-acetyl)-L-lysine... 

Ethyl a-acetaminoacrylate added portionwise with vigorous stirring at 0-10° to a soln. of Na-acetyl-L-lysine in 0.6 N NaOH, and stirring continued 6 hrs. at room temp. N -(2-acetamino-2-ethoxycarbonylethyl)-Na-acetyl-L-lysine. Y ... 

Table 5. Second-order rate constants (k2 in min ) for reaction of N-acetyldehydroalanine methyl ester with the e-NH2 group of N-a-acetyl-L-lysine and with the SH groups of cysteine at various pH s.

A -[A -[N-[iV-acetyl-l- >-(phenylmethyl)-4,6-0-(phenyl-methyIene)muramoyI]-L-alanyl]-D-a-glutaminyI]-A -[(phenylmethoxy)carbonyl]-L-lysine phenylmethyl ester... 

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