Lysine Lys

Several years ago Makino et al. 86) studied the influence of anions on the conformation of poly-[L-methionine-S-methylsulfonium] salts in solution. They found that especially perchlorate will induce a-helix formation whereas Cl- and Br do not. Since then several authors 87 92) have found a similar a-helix inducing effect in the case of poly-L-lysine (Lys) and other BPAA at low pH-values where the polymer molecules usually attain an extended conformation due to the electrostatic repulsion of the ammonium groups. Therefore, the a-helix inducing effect is obviously an... 

Chlorophyll, heme, vitamin B,2, and a host of other substances are bio-synthesized from porphobilinogen (PEG), which is itself formed from condensation of two molecules of 5-aminolevulinate. The two 5-aminolevulinates are bound to lysine (Lys) amino acids in the enzyme, one in the enamine form and one in the imine form, and their condensation is thought to occur by the following steps. Using curved arrows, show the mechanism of each step. 

Copolymers of a-hydroxy acids and a-amino acids are one type of poly(ester-amide)s and are called polydepsipeptides (PDPs) [17]. Since some of natural occurring a-amino acids, typically Asp, Glu, lysine (Lys), cysteine (Cys), serine (Ser), and threonine (Thr), possess reactive (hydrophilic) side-chain groups, PDPs... 

Fig. 57. Model and electron density in rubredoxin after refinement at 1.2 A resolution, for (a) the well-ordered lysine, Lys-46 (temperature factor average of 9.2 for the outer four atoms of the side chain) (b) the best of the disordered lysines, Lys-3 (temperature factor average of 43.6 for the outer four side chain atoms). From Watenpaugh et al. (1980), Fig. 12, with permission.

Aspartic acid (Asp) Lysine (Lys) Arginine (Arg) Asparagine (Asn) Glutamine (Gin)... 

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