We developed a novel strategy by oxidation-derivatization combined mass spectrometry analysis for the determination of 5-hydroxymethylcytosine and 5-formylcytosine in both DNA and RNA. We reported the presence of 5-formylcytosine in RNA of mammals and found that ascorbic acid and hydroquinone can increase the oxidation of 5-methylcytosine to 5-hydroxymethylcytosine in DNA and RNA.

Recently, novel taurine-containing uridine derivatives were discovered in mammalian mitochondrial tRNAs, and these modified ribonucleosides existed at the first position of the anti-codon. This paper describes the chemical synthesis of these novel uridine derivatives, 5-taurinomethyluridine (tau m5U) and 5-taurinomethyl-2-thiouridine (tau m5s2U). These taurine-containing uridine derivatives wer...

I our recently published article on the structures and base pair opening dynamics of Dickerson−Drew dodecamer (DDD) duplexes with incorporated 5-hydroxymethylcytosine (5hmC), 5-formylcytosine (5fC), or 5-carboxylcytosine (5caC), we inadvertently failed to reference two publications by others who had reported structures of the DDD with single 5hmC residues inserted per strand. Spingler and co-wo...

Tet family proteins have the ability to convert 5-methylcytosine (mC) to 5-hydroxymethylcytosine, and further to 5-formylcytosine and 5-carboxycytosine. We found that CGmCGCG can be the substrate of Tet protein, and observed iterative oxidation of mC by HPLC analysis. We also demonstrated that Tet protein favours single-stranded DNA over double-stranded DNA.

5-Formylcytosine (5fC) and 5-formyluracil (5fU) are natural nucleobase modifications that are generated by oxidative modification of 5-methylcytosine and thymine (or 5-methyluracil). Herein, we describe chemoselective labeling of 5-formylpyrimidine nucleotides in DNA and RNA by fluorogenic aldol-type condensation reactions with 2,3,3-trimethylindole derivatives. Mild and specific reaction condi...

An enzymatic preparation from human brain converts tryptamine to tryptoline (9H-1,2,3,4-tetrahydropyrido(3,4-b)indole) in the presence of 5-methyltetrahydrofolic acid. Similarly, N-methyltryptamine and 5-hydroxytryptamine yield 1-methyltryptoline and 5-hydroxytryptoline, respectively. Neither in vitro nor in vivo formation of these compounds by human tissues has been described.