In organic chemistry, atoms other than carbon and hydrogen are generally referred to as heteroatoms. The most common heteroatoms are nitrogen, oxygen and sulfur. Now I present to you an article called Role of the Tyr270 residue in 2-methyl-3-hydroxypyridine-5-carboxylic acid oxygenase from Mesorhizobium loti, published in 2017-02-28, which mentions a compound: 27828-71-3, mainly applied to methylhydroxypyridinecarboxylate oxygenase Mesorhizobium active site tyrosine role; crystal structure methylhydroxypyridinecarboxylate oxygenase Mesorhizobium; 2-Methyl-3-hydroxypyridine-5-carboxylic acid oxygenase; Flavoenzyme; Mesorhizobium loti; Pyridine-ring opening reaction; Tyr270; Vitamin B(6) degradation pathway I, Category: catalyst-palladium.
The flavoenzyme, 2-methyl-3-hydroxypyridine-5-carboxylate oxygenase (MHPCO), catalyzes the cleavage of the pyridine ring of 2-methyl-3-hydroxypyridine-5-carboxylic acid (MHPC) in the presence of NADH, O2, and water. MHPCO also catalyzes the NADH oxidation reaction uncoupled with ring opening in the absence of MHPC (the basal activity). The enzyme showed activity toward not only MHPC but also 5-hydroxynicotinic acid (5HN) and 5-pyridoxic acid (5PA). The reaction rate toward 5PA was extremely low (5% of the activity toward MHPC or 5HN). The authors determined the crystal structures of MHPCO without substrate and the MHPCO/5HN and MHPCO/5PA complexes, together with a Y270F mutant without substrate and its 5HN complex. The Tyr-270 residue was located in the active site and formed H-bonds between the Oη atom and water mols. to make the active site hydrophilic. Although Tyr-270 took a fixed conformation in the structures of the MHPCO and MHPCO/5HN complex, it took 2 conformations in its 5PA complex, accompanied by 2 conformations of the bound 5PA. In the wild-type (WT) enzyme, the turnover number of the ring-opening activity was 6800-fold that of the basal activity (1300 and 0.19 s-1, resp.), whereas no such difference was observed in the Y270F (19 and 7.4 s-1) or Y270A (0.05 and 0.84 s-1) mutants. In the Y270F/5HN complex, the substrate bound ∼1 Å farther away than in the WT enzyme. These results revealed that Tyr-270 is essential to maintain the WT conformation, which in turn enhances the coupling of the NADH oxidation with the ring-opening reaction.
After consulting a lot of data, we found that this compound(27828-71-3)Category: catalyst-palladium can be used in many types of reactions. And in most cases, this compound has more advantages.
Reference:
Chapter 1 An introduction to palladium catalysis,
Palladium/carbon catalyst regeneration and mechanical application method