ADP-ribosylation (ADPr) is a posttranslational modification (PTM) of proteins that controls many cellular processes, including DNA repair, transcription, chromatin regulation and mitosis. A number of proteins catalyse the transfer and hydrolysis of ADPr, and also specify how and when the modification is conjugated to the targets. We recently discovered a new form of ADPr that is attached to ser...

Glycosyltransferases are specific enzymes that catalyse the transfer of monosaccharide moieties to biological substrates, including proteins, lipids and carbohydrates. These enzymes are present from prokaryotes to humans, and their glycoconjugate products are often vital for survival of the organism. Many glycosyltransferases found in fungal pathogens such as Cryptococcus neoformans do not exis...

Iron-sulfur (Fe/S) cluster-containing proteins catalyse a number of electron transfer and metabolic reactions. Little is known about the biogenesis of Fe/S clusters in the eukaryotic cell. Here, we demonstrate that mitochondria perform an essential role in the synthesis of both intra- and extra-mitochondrial Fe/S proteins. Nfs1p represents the yeast orthologue of the bacterial cysteine desulfur...

NAD+ glycohydrolase (NAD+ nucleosidase, EC 3.2.2.6) can be solubilized from calf spleen microsomes (microsomal fractions) by steapsin or by detergents to yield respectively a hydrophilic (i.e. water-soluble) and a hydrophobic form of the enzyme. The detergent-solubilized enzyme was successfully reassociated into phosphatidylcholine liposomes either by a cholate-dialysis or by a gel-filtration p...

Motor enzymes catalyse chemical reactions, like the hydrolysis of ATP, and in the process they also perform work. Recent studies indicate that motor enzymes perform work with specific biochemical steps in their catalysed reactions, challenging the classical view that work can only be performed within a biochemical state. To address these studies an alternative class of models, often referred to...

1. An enzyme (EC 2.8.2.1) that catalyses the transfer of sulphate from adenosine 3'-phosphate 5'-sulphatophosphate to phenols was purified approx. 2000-fold from male rat livers. 2. The purified preparation did not catalyse the sulphurylation of dehydroepiandrosterone, butan-1-ol, l-tyrosine methyl ester, 1-naphthylamine or serotonin. 3. At pH8.0 and 37 degrees C the K(m) values of the enzyme f...