217 research outputs found
Role of a conserved arginine residue during catalysis in serine palmitoyltransferase
AbstractAll sphingolipid-producing organisms require the pyridoxal 5′-phosphate (PLP)-dependent serine palmitoyltransferase (SPT) to catalyse the first reaction on the de novo sphingolipid biosynthetic pathway. SPT is a member of the alpha oxoamine synthase (AOS) family that catalyses a Claisen-like condensation of palmitoyl-CoA and l-serine to form 3-ketodihydrosphingosine (KDS). Protein sequence alignment across various species reveals an arginine residue, not involved in PLP binding, to be strictly conserved in all prokaryotic SPTs, the lcb2 subunits of eukaryotic SPTs and all members of the AOS family. Here we use UV–vis spectroscopy and site-directed mutagenesis, in combination with a substrate analogue, to show that the equivalent residue (R370) in the SPT from Sphingomonas wittichii is required to form the key PLP:l-serine quinonoid intermediate that condenses with palmitoyl-CoA and thus plays an essential role enzyme catalysis.Structured summary of protein interactionsSPT binds to SPT by molecular sieving (View interaction
Crystallographic Snapshots of Tyrosine Phenol-lyase Show That Substrate Strain Plays a Role in C–C Bond Cleavage
Why is monoalkylation versus bis-alkylation of the Ni(II) complex of the Schiff base of (S)-N-(2-benzoylphenyl)-1-benzylpyrrolidine-2-carboxamide and glycine so selective? MP2 modelling and topological QTAIM analysis of chiral metallocomplex synthons of α-amino acids used for the preparation of radiopharmaceuticals for positron emission tomography
Structural, Biochemical, and In Vivo Investigations of the Threonine Synthase from Mycobacterium tuberculosis
D2O-Alanine exchange reactions catalyzed by Alanine Racemase and Glutamic Pyruvic Transaminase
A simple method for determination of stereospecificity of aminotransferases for C-4′ hydrogen transfer of the coenzymes
Mechanism and stereochemistry of α,β-elimination of l-tyrosine catalysed by tyrosine phenol-lyase
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