S-Adenosyl-S-carboxymethyl-L-homocysteine: a novel cofactor found in the putative tRNA-modifying enzyme CmoA

The putative methyltransferase CmoA is involved in the nucleoside modification of transfer RNA. X-ray crystallography and mass spectrometry are used to show that it contains a novel SAM derivative, S-adenosyl-S-carboxymethyl-L-homocysteine, in which the donor methyl group is replaced by a carboxymethyl group.

Decision making in xia2

The basis for decision making in the program xia2 is described, alongside the framework to support these protocols. Where appropriate, applications of these protocols to interactive data processing are highlighted.