BACKGROUND Altered methyl group and homocysteine metabolism were tissue-specific, persistent, and preceded hepatic DNA hypomethylation in type 1 diabetic rats. Similar metabolic perturbations have been shown in the Zucker (type 2) diabetic fatty (ZDF) rat in the pre-diabetic and early diabetic stages, but tissue specificity and potential impact on epigenetic marks are unknown, particularly duri...

It is now firmly established that X-adenosylmethionine is the most important biological methyl donor in a variety of transmethylation reactions (I). However, in spite of the large number of methyltransferases that have been described, little information is available concerning the enzymatic mechanism of the methyl transfer from S-adenosylmethionine to a substrate resulting in the formation of a...

Bacterial ribosomal protein L11 is post-translationally trimethylated at multiple residues by a single methyltransferase, PrmA. Here, we describe four structures of PrmA from the extreme thermophile Thermus thermophilus. Two apo-PrmA structures at 1.59 and 2.3 A resolution and a third with bound cofactor S-adenosyl-L-methionine at 1.75 A each exhibit distinct relative positions of the substrate...

The formation of homocysteine thiolactone (HcyTl) from homocysteine occurs in all examined so far organisms including bacteria, yeast, and humans. Protein N-homocysteinylation at the ε-amino group of lysine is an adverse result of HcyTl accumulation. Since tagging of proteins by ubiquitination before their proteasomal degradation takes place at the same residue, we wondered how N-homocysteinyla...

background: betaine has been shown to be antioxidantand methyl donor effects in our recent studies. objectives: inthe present study, the antioxidant and methyl donor properties ofbetaine in levodopa/benserazide-mediated hyperhomocysteinemiaand levodopa-induced oxidative stress in rat's kidney wereexamined. methods: sprague-dawley male rats were dividedinto levodopa (ld), betaine (bet.), levodop...

Methionine metabolism plays a central role in methylation reactions, production of glutathione and methylarginines, and modulating homocysteine levels. The mechanisms by which these are affected in NAFLD are not fully understood. The aim is to perform a metabolomic, molecular and epigenetic analyses of hepatic methionine metabolism in diet-induced NAFLD. Female 129S1/SvlmJ;C57Bl/6J mice were fe...