It is now generally agreed that in the process of aerobic oxidative phosphorylations there is no direct interaction of orthophosphate with the various oxidizable substrates which provide the energy necessary for the phosphorylation. Phosphorylation takes place during the passage of electrons from substrate to molecular oxygen. Since there are three main oxidationreduction systems of varied pote...

and that it is betaine which serves as the immediate donor of methyl groups in transmethylation reactions. In view of an earlier finding that betaine was readily demethylated to glycine in the rat (4), it was considered of interest to compare injected isotopic choline and betaine as precursors of the glycine moiety of hippuric acid in the intact animal. The present finding that betaine and chol...

Choline is an essential nutrient Choline (Cho), a quaternary amine, is an essential nutrient supplied by the diet (1, 2). Choline uptake and intracellular metabolism during the prenatal period were shown to have a critical role in brain development and cognitive processes (3, 4). Choline is a precursor in several key biochemical pathways as demonstrated below in scheme 1. Scheme 1: Metabolic Fa...

Chenopods synthesize betaine by a two-step oxidation of choline: choline --> betaine aldehyde --> betaine. The pathway is chloroplastic; the first step has been shown in isolated spinach (Spinacia oleracea L.) chloroplasts to be O(2)- and light-dependent, the role of light being to provide reducing power (P Weigel, EA Weretilnyk, AD Hanson 1988 Plant Physiol 86: 54-60). Here, we report use of i...

As a first step towards the elucidation of the molecular mechanisms responsible for the utilization of choline and glycine betaine (betaine) either as carbon and nitrogen sources or as osmoprotectants in Sinorhizobium meliloti, we selected a Tn5 mutant, LTS23-1020, which failed to grow on choline but grew on betaine. The mutant was deficient in choline dehydrogenase (CDH) activity, failed to ox...

Effects of different levels of choline and garlic powder on performance, liver health and immune response in broiler chickens were evaluated in this study. A factorial experiment with 2 dietary choline levels (the recommended level in Ross 308 broiler guidelines and 25 % less than the recommendation) and 3 dietary garlic powder levels (0, 5 or 10 g/kg diet) was conducted using Ross 308 broiler ...

loxiazine ring. Effect of pH on fluorescence of the flavin peptide was shown in fig. 1. The fluorescence of the flavin peptide was quenched at neutral and alkaline pH ranges. This shows that the amino acid linked to flavin ring is a histidyl residue.6) The pKa. value of the flavin peptide was found to be about 4.6, which was almost identical with that of the authentic 8a-[7V(3)-histidyl]ribofla...

Choline dehydrogenase (EC 1.1.99.1) catalyzes the four-electron oxidation of choline to glycine-betaine via a betaine-aldehyde intermediate. Such a reaction is of considerable interest for biotechnological applications in that transgenic plants engineered with bacterial glycine-betaine-synthesizing enzymes have been shown to have enhanced tolerance towards various environmental stresses, such a...

IT was shown by Mann & Quastel [1937] that choline is oxidized by slices or extracts of rat liver and kidney. The oxidation product was isolated and identified as betaine aldehyde. Some evidence was obtained that betaine aldehyde is also oxidized by the same tissues though at a much slower rate than choline and it was suggested that the oxidation product in this case is betaine. Bernheim & Bern...