Omithin

Many kinds of amino acids (eg, L-lysine, L-omithine, t-phenylalanine, L-threonine, L-tyrosine, L-valine) are accumulated by auxotrophic mutant strains (which are altered to require some growth factors such as vitamins and amino acids) (Table 6, Primary mutation) (22). In these mutants, the formation of regulatory effector(s) on the amino acid biosynthesis is genetically blocked and the concentration of the effector(s) is kept low enough to release the regulation and iaduce the overproduction of the corresponding amino acid and its accumulation outside the cells (22). 

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. 

Uchegbu and coworkers have studied the complexation and delivery of DNA using a unique poly(amino acid)-based polymer vesicle. A polymer of either poly (L-lysine) or poly(L-omithine) was functionalized with methoxy-poly(ethylene glycol) (mPEG) and hydrophobic palmitic acid chains to synthesize an amphiphilic triblock of either mPEG-6-poly(L-lysine)-6-palmitoyl or mPEG-Z>-poly(L-omithine)-6-palmitoyl. Vesicles formed from these polymers were complexed with DNA and showed improved transfection in vitro over poly(amino acid) complexed with DNA or DNA alone [82]. 

Three-dimensional structures of the periplasmic lysine/arginine/omithine-binding protein with and without a ligand, J. Biol. Chem 268 11348 (1993). 

Other adjunctive therapies that may be considered for patient s refractory to standard therapy include L-omithine L-aspartate or flumazenil 0.2 mg up to 15 mg IV. 

Fusarinines (19) produced by several fungal genera comprise the acyl unit (Z)-5-hydroxy-3-methyl-pent-2-enoic acid (anhydromevalonic acid) (Fig. 5, a) bound to W -hydroxy-L-omithine. They can be a linear monomer, dimer (fusarinine A) or trimer (fusarinine B) (the monomer can also be ( )-configured) 172). Fusarinine B is possibly identical with coprogen C 89). 

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... 

The polarographic method has been used to determine the stability constants and kinetic parameters of ternary complexes of Zn(II) with L-lysine, L-omithine, L-serine, L-phenylglycine, L-phenylalanine, L-glutamic acid, and L-aspartic acid as primary ligands and picoline as secondary ligand at pH 8.5 [103] and also of zinc complexation by extracellular polymers extracted from activated sludge [104]. 

New aminophosphines (19) were obtained from (S>omithine recently45. ... 

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