The glycine-serine interconversion, catalysed by glycine decarboxylase and serine hydroxymethyltransferase, is an important reaction of primary metabolism in all organisms including plants, by providing one-carbon units for many biosynthetic reactions. In plants, in addition, it is an integral part of the photorespiratory metabolic pathway and produces large amounts of photorespiratory CO(2) wi...

Here, we describe the combination of OleTJE with a light-driven in situ H2O2-generation system for the selective and quantitative conversion of fatty acids into terminal alkenes. The photobiocatalytic system shows clear advantages regarding enzyme activity and yield, resulting in a simple and efficient system for fatty acid decarboxylation.

Large quantities of oxalic acid accumulate in the cell sap of various plants and as a major product of carbohydrate metabolism by many molds. A recent investigation in our laboratory revealed that oxalic acid was produced from oxalacetic acid by an enzyme system which was isolated from the mycelia of Aspergillus niger (1). It was also demonstrated that oxalic acid was converted to formic acid a...

Pyruvoyl-dependent arginine decarboxylase (PvlArgDC) catalyzes the first step of the polyamine-biosynthetic pathway in plants and some archaebacteria. The pyruvoyl group of PvlArgDC is generated by an internal autoserinolysis reaction at an absolutely conserved serine residue in the proenzyme, resulting in two polypeptide chains. Based on the native structure of PvlArgDC from Methanococcus jann...

Decarboxylation of mandelylthiamin in aqueous solution is analyzed by means of quantum mechanics/molecular mechanics simulations including solvent effects. The free energy profile for the decarboxylation reaction was traced, assuming equilibrium solvation, while reaction trajectories allowed us to incorporate nonequilibrium effects due to the solvent degrees of freedom as well as to evaluate th...

The photochemistry of phthalimide derivatives of the electron-rich amino acids tyrosine, histidine and tryptophan 8-10 was studied with respect to photoinduced electron-transfer (PET) induced decarboxylation and Norrish II bond cleavage. Whereas exclusive photodecarboxylation of the tyrosine substrate 8 was observed, the histidine compound 9 resulted in a mixture of histamine and preferential N...

Radiation Damage, Amino Acid Transformation, Electron Microscopy For the transformation o f glutamic acid into a-aminobutyric acid upon irradiation a decarboxylation mechanism involving the formation of C 0 2 has been proposed pre­ viously. Here we present further experimental evidence in favour of this mechanism. Additionally the formation of CO as a decarboxylation product has been detected; ...

Nine isotopomers of tryptamine and its halogen derivatives, labeled with deuterium, tritium in side chain, i.e., [(1R)-2H]-, [(1R)-3H]-, 5-F-[(1R)-2H]-, 5-F-[(1R)-3H]-, 5-Br-[(1R)-2H]-, double labeled [(1R)-2H/3H]-, 5-F-[(1R)-2H/3H]-, and ring labeled [4-2H]-, and [5-2H]-tryptamine, were obtained by enzymatic decarboxylation of l-Trp and its appropriate derivatives in deuteriated or tritiated m...

Isolated pea leaf mitochondria oxidatively decarboxylate added glycine. This decarboxylation could be linked to the respiratory chain (in which case it was coupled to three phosphorylations) or to mitochondrial malate dehydrogenase when oxalacetate was supplied. Decarboxylation rates measured as O(2) uptake, or CO(2) and NH(3) release were adequate to account for whole leaf photorespiration. Ox...