Cytosine DNA methylation is found in Drosophila melanogaster but absent in Saccharomyces cerevisiae, Schizosaccharomyces pombe, and other yeast species.

The methylation of cytosine to 5-methylcytosine (5-meC) is an important epigenetic DNA modification in many bacteria, plants, and mammals, but its relevance for important model organisms, including Caenorhabditis elegans and Drosophila melanogaster, is still equivocal. By reporting the presence of 5-meC in a broad variety of wild, laboratory, and industrial yeasts, a recent study also challenged the dogma about the absence of DNA methylation in yeast species. We would like to bring to attention that the protocol used for gas chromatography/mass spectrometry involved hydrolysis of the DNA preparations.

Metabolic syndrome components are associated with DNA hypomethylation.

Background: Disturbances of DNA methylation have been associated with multiple diseases, including cardiovascular disease, cancer and, as some have suggested, glucometabolic disturbances. Our aim was to assess the association of the metabolic syndrome and its individual components with DNA methylation in a population-based study.

Materials And Methods: In a human population (n = 738) stratified by age, sex and glucose metabolism, we explored associations of the metabolic syndrome according to National Cholesterol Education Program/Adult Treatment Panel-III criteria and its individual components (fasting glucose, high-density lipoprotein cholesterol, triglycerides, blood pressure, waist circumference) with global leukocyte DNA methylation.

The influence of lithium on calcium homeostasis in older patients in daily clinical practice.

Background: Lithium can influence calcium homeostasis resulting in changes in parathormone set point and renal calcium handling. The clinical significance of these changes in older patients is unknown. The objective of this study was to investigate the possible association between duration of lithium treatment and corrected calcium, parathormone and 24-h urinary calcium excretion in older psychiatric patients corrected for renal function and vitamin 25OH D and also to estimate the point prevalence of hypercalcemia and raised parathormone.

Folic acid supplementation does not reduce intracellular homocysteine, and may disturb intracellular one-carbon metabolism.

Background: In randomized trails, folic acid (FA) lowered plasma homocysteine, but failed to reduce cardiovascular risk. We hypothesize this is due to a discrepancy between plasma and intracellular effects of FA.

Methods: In a double-blind trial, 50 volunteers were randomized to received 500 µg FA daily for 8 weeks, or placebo.

Protein arginine methylation is more prone to inhibition by S-adenosylhomocysteine than DNA methylation in vascular endothelial cells.

Methyltransferases use S-adenosylmethionine (AdoMet) as methyl group donor, forming S-adenosylhomocysteine (AdoHcy) and methylated substrates, including DNA and proteins. AdoHcy inhibits most methyltransferases. Accumulation of intracellular AdoHcy secondary to Hcy elevation elicits global DNA hypomethylation.

Plasma choline and betaine correlate with serum folate, plasma S-adenosyl-methionine and S-adenosyl-homocysteine in healthy volunteers.

Background: Choline is essential for mammalian cell function. It plays a critical role in cell membrane integrity, neurotransmission, cell signaling and lipid metabolism. Moreover, choline is involved in methylation in two ways: a) its synthesis requires methyl groups donated by S-adenosyl-methionine (AdoMet); and b) choline oxidation product betaine methylates homocysteine (Hcy) to methionine (Met) and produces dimethylglycine.

Carbon neutral electricity production by Synechocystis sp. PCC6803 in a microbial fuel cell.

The aim of this work was to illustrate the use of photosynthetic microbes in a microbial fuel cell to produce electricity without the requirement of an external carbon source. This research here describes the use of a cyanobacterium Synechocystis PCC6803, to produce electricity without any net CO(2) production in a two-chambered MFC. Conditions for optimum electricity production were determined through standardizing operating parameters.

No effect of folic acid supplementation on global DNA methylation in men and women with moderately elevated homocysteine.

A global loss of cytosine methylation in DNA has been implicated in a wide range of diseases. There is growing evidence that modifications in DNA methylation can be brought about by altering the intake of methyl donors such as folate. We examined whether long-term daily supplementation with 0.

Global DNA methylation: comparison of enzymatic- and non-enzymatic-based methods.

Background: The most frequently used methods for measuring global DNA methylation are based on two different principles: the use of methylation-sensitive restriction endonucleases followed by analysis of the obtained fragments, or the hydrolysis of genomic DNA followed by specific detection and quantification of the 5-methylcytosine content. We aimed to compare two different methods for evaluation of global DNA methylation: the cytosine extension assay after enzymatic digestion of DNA (Cyt-Ext), and a recently described method using liquid chromatography-electrospray ionization-tandem mass spectrometry after DNA hydrolysis (LC-MS/MS).

Methods: Both approaches were applied to evaluate global DNA methylation in leukocyte DNA from 96 healthy subjects.

Gene-environment interactions in the causation of neural tube defects: folate deficiency increases susceptibility conferred by loss of Pax3 function.

Risk of neural tube defects (NTDs) is determined by genetic and environmental factors, among which folate status appears to play a key role. However, the precise nature of the link between low folate status and NTDs is poorly understood, and it remains unclear how folic acid prevents NTDs. We investigated the effect of folate level on risk of NTDs in splotch (Sp(2)(H)) mice, which carry a mutation in Pax3.

Global DNA methylation measured by liquid chromatography-tandem mass spectrometry: analytical technique, reference values and determinants in healthy subjects.

Background: Alterations in global DNA methylation are implicated in various pathobiological processes. We describe a liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS) method for determination of cytosine and 5-methylcytosine in DNA.

Methods: DNA was hydrolyzed using formic acid.

Red blood cell folate vitamer distribution in healthy subjects is determined by the methylenetetrahydrofolate reductase C677T polymorphism and by the total folate status.

Background: Red blood cells (RBCs) represent a storage pool for folate. In contrast to plasma, RBC folate can appear in different biochemical isoforms. So far, only the methylenetetrahydrofolate reductase (MTHFR) 677 TT genotype has been identified as a determinant of RBC folate vitamer distribution.

Quantitative determination of erythrocyte folate vitamer distribution by liquid chromatography-tandem mass spectrometry.

Background: Given the role of folate in many disorders, intracellular distribution of folate vitamers is of potential clinical importance. In particular, accumulation of non-methyltetrahydrofolates due to altered partitioning of folate metabolism at the level of methylenetetrahydrofolate is of interest.

Methods: We describe a positive-electrospray liquid chromatography tandem mass spectrometry (LC-MS/MS) method that allows determination of erythrocyte folate vitamer distribution by accurately measuring both 5-methyltetrahydrofolate (5-methylTHF) and non-methyl folate vitamers.

Design, synthesis, and biological evaluation of a dual tumor-specific motive containing integrin-targeted plasmin-cleavable doxorubicin prodrug.

The design, synthesis, and initial biological evaluation of a doxorubicin prodrug that contains a dual tumor specific moiety, which allows enhanced tumor recognition potential, is reported. Both a tumor-specific recognition site and a tumor selective enzymatic activation sequence are incorporated in the prodrug. The first tumor-specific sequence is the bicyclic CDCRGDCFC (RGD-4C) peptide that selectively binds alpha v beta 3 and alpha v beta 5 integrins.