D-Omithine

Likely impurities are citrulline, arginine and D-omithine. Crystd from water by adding 4 volumes of EtOH and dried in a vacuum desiccator over fused CaCl2. 

Staphyloferrin A (Fig. 20, 65) is a second siderophore of Staphylococcus spp. (226). D-Omithine coimects the two citric acid parts. Due to the unsymmetrical link the central C-atoms of the citric acid units are chiral, but their stereochemistry has not been determined. Another consequence of the asymmetric structure is that two mono- and one di-dehydration products are observed. Staphyloferrin A forms a 1 1 Fe -to-ligand complex, which is preferentially A-configured. For steric considerations only cis-(SR ) or cis-(RS ) arrangements can be considered. Uptake experiments with Fe showed that it is a true siderophore (193). 

Eng-Wihnot DL, Rahman A, Mendenhall JV, Grayson SL, van der Hehn D (1984) Molecular Structure of Eerric Neurosporin, a Minor Siderophore-hke Compound Containing iV -hydroxy-D-omithine. J Am Chem Soc 106 1285... 

Aminomutases. The enzymes i -[5-Iysine mutase (which is also D-a-Iysine mutase) and D-omithine... 

Aminomutases. The enzymes L-p-lysine mutase (which is also D-a-lysine mutase) and D-omithine mutase catalyze the transfer of an co-amino group to an adjacent carbon atom (Table 16-1). Two proteins are needed for the reaction pyridoxal phosphate is required and is apparently directly involved in the amino group migration. In the P-lysine mutase the 6-amino group of L-P-lysine replaces the pro-S hydrogen at C-5 but with inversion at C-5 to yield (3S, 5S)-... 

Eng-Wilmot, D.L., A. Rahman, J.V. Mendenhall, S.L. Grayson, and D. van der Helm Molecular Structure of Ferric Neurosporin, a Minor Siderophore-like Compound Containing N -Hydroxy-D-omithine. J. Amer. Chem. Soc. 106,1285 (1984). 

D-valine, iV-methyl-L-valine, L-norvaline, L-y-formylmethylnorvaline L-ornithine, D-omithine, iV-hydroxy-L-omithine L-lanthionine, /J-methyl-L-lanthionine... 

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