Sandbox GGC1

Crystal Structure of yeast nitronate monooxygenase from Cyberlindera saturnas

spinqualitylabelsall models Caption for this structure Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image   Print3D Nitronate Monooxygenase (NMO) is an FMN-dependent (flavin mononucleotide) enzyme that oxidizes the neurotoxin propionate 3-nitronate (P3N). FMN is produced from riboflavin or Vitamin B2 by riboflavin kinase and can function as a prosthetic group for NADH dehydrogenase . NMO is widely known as the best system for P3N detoxification in many different organisms. Function NMOs are FMN-dependent enzymes that can quickly and efficiently catalyze the oxidation of P3N. They can also oxidize alkyl nitronates but with lower catalytic efficiency in comparison to P3N. Recent structural studies suggest there are two classes of NMOs, Class I and Class II. Class I NMOs contain about 450 NMO gene products from bacteria, fungi, and animals. The enzymes in this class only oxidize P3N and nitronate analogues. Class II NMOs consists of small groups of ten fungal gene products and can oxidize nitronate and nitroalkaline analogues. In Class I NMOs, the enzyme mechanism is first initiated by a single electron transfer from P3N to the flavin that is enzyme-bound. The product is then oxidized by dioxygen and forms superoxide. The superoxide and P3N radial will then interact in the active site and form 3-peroxy-3-nitro-propanoate, which will decay to products with time. Disease P3N can be considered a toxic compound that is commonly found in legumes, fungi, and leaf beetles. During hydrolysis, P3N is released from esters and acts as an irreversible inhibitor of mitochondrial succinate dehydrogenase. Succinate dehydrogenase is a key enzyme in the Kreb's cycle and the electron transport chain for oxidative phosphorylation. Because this is inhibited, it can lead to a variety of neurological disorders and can even cause death. P3N is found in plant shoots and leaves which more than likely acts as a defense mechanism for herbivores. In laboratories, P3N is also used in small amounts to poison mitochondria in rats. This induces symptoms similar to Huntington's disease and is used to develop possible treatments. Structural highlights This is a sample scene created with SAT to color by Group, and another to make a transparent representation of the protein. You can make your own scenes on SAT starting from scratch or loading and editing one of these sample scenes. This is the structure of the yeast CsNMO. This view shows the alpha helixes and beta pleaded sheets of nitronate monooxygenase. There are eight parallel beta strands that are depicted in that are surrounded by eight alpha helixes. FMN Binding site is formed with hydrogen bonds with main chain amino acids of G240, G261, and T262. This is a view of the FMN Binding Site with labeled amino acid residues.