Proline, oxidation

Figure 1.18 Reaction of proline, arginine, and lysine residues with hydroxyl radical results in oxidation of side-chain structures that form carbonyls. Both arginine and proline oxidation result in the same product.

Figure B2(i) The pathway for conversion of proline and alanine in the flight muscle of the tsetse fly the major ATP-generating pathway. Alanine aminotransferase is essential for the proline oxidation pathway in order for glutamate to enter the Krebs cycle as oxoglutarate and pyruvate to be converted to alanine, the end of the pathway. It is assumed that the pathway is the same for the Colorado beetle, but no studies have been reported.

Further elaboration of the sulfur cycloadducts could be achieved by the use of a Pummerer rearrangement in the syntheses of 5-(hydroxymethyl)prolines. Oxidation of adduct 298 to sulfoxide 299, followed by treatment with TEA in DCM and quenching with either methanol or benzyl alcohol, delivered the Pummerer products 300 in 57% yield for R = Me and 38% for R = Bn as single diastereoisomers. Raney Ni desulfurization and Pearlman s catalyst mediated hydrogenolysis, for R = Bn furnished the final enantiopure proline derivative (Scheme 3.99). 

Nitrogen Metabolism "" " i i (ammonia incorporation, amino acid biosynthesis, nitrate/nitrite reduction, proline oxidation, polyamine biosynthesis)... 

In studies on the role of the adrenal hormones in amino acid metabolism, cortisone has been reported to inhibit the incorporation of glycine and alanine into liver proteins and to increase the catabolism of glycine (Clark, 1950 Sinex, 1951 Barton, 1951). Proline oxidation by kidney homogenates was depressed by adrenalectomy and restored to normal by cortisone (Umbreit and Tonhazy, 1951a, 1951b). 

Furthermore, it has been also shown that an exogenous application of proline to the nutrient medium of in vitro grown oregano plants elicited the accumulation of rosmarinic acid and other phenolic compounds in that plant. This suggests that mitochondrial proline oxidation could drive the oxidative pentose phosphate pathway by recycling glutamic acid into the cytosol to generate a proline redox cycle. 

Kwon, Y.I., Apostolidis, E., Labbe, R.G., and Shetty, K. 2007. Inhibition of Staphylococcus aureus by Phenolic Phytochemicals of Selected Clonal Herbs Species of Lamiaceae Family and Likely Mode of Action through Proline Oxidation. Food Biotechnology, 21(1), 71-89. 

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