Aspartic acid characterisation

Aspartic Acid.—A portion of the aspartic acid, after separation from phenylalanine ester and after hydrolysis by baryta, may separate as barium salt this is the barium salt of racemic aspartic acid. The remainder is isolated, when the glutamic acid has been removed as hydrochloride, by boiling with lead hydroxide and treating with hydrogen sulphide to remove hydrochloric acid and lead respectively, and by crystallising from water. It maybe characterised by conversion into its copper salt, or by analysis, and is estimated by its weight. 

Ru(PPh3)(H2O)j(SB "0 constimtes a series of complexes, made from RuClj(PPh3)3 and a chiral Schiff base SB obtained from salicylaldehyde and the L-forms of alanine, valine, serine, arginine, cysteine and aspartic acid. They were characterised by IR, circular dichroism, H and C[ H] NMR spectroscopies and by cyclic voltammetry. The supposed structure of one is shown in Fig. 1.41 [917]. 

Figure 4. Alignment of PelZ and PelC amino acid sequences. The vertical lines indicate identical amino acids and the two points indicate homologous amino acids. The bold letters correspond to the residues probably involved in Ca + binding or catalytic function(s). The two aspartate residues probably involved in Ca binding are indicated with an asterisk. The invariant residues, probably involved in PGA cleavage, are indicated with an open circle. The folding in p-sheets is characterised by the underlined amino acids. Double underlining of PelZ residues is deduced from Chou Fasman and Robson Gamier folding predictions.

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