Leghemoglobin reductase
This enzyme belongs to the family of oxidoreductases, specifically those acting on NADH or NADPH with a heme protein as acceptor.Oxygenated Lb2+ (Lb2+O2) readily autoxidizes to ferric Lb (Lb3+) generating O2− in the presence of trace amounts of transition metals, chelators and toxic metabolites (such as nitrite, superoxide radical and peroxides),[2] however Lb2+ is the predominant form in nodules.In 1984 Klucas and collaborators[9] purified a protein with ferric Lb reductase (FLbR) activity from soybean nodules.These investigations by Klucas and collaborators[9] also showed that the oxidation of NADH and reduction of Lb3+ was undetectable when O2 was removed from the reaction system, but all were restored upon re-addition of O2, which indicated that the FLbR activity is O2-dependent.Soybean FLbR is a flavoprotein with flavin adenine dinucleotide (FAD) as the prosthetic group and consists of two identical subunits, each having a molecular mass of 54 kDa.
EC no.CAS no.IntEnzBRENDAExPASyMetaCycGene OntologyPubMedenzymologyenzymecatalyzeschemical reactionleghemoglobinphytoglobinoxidoreductasessystematic nametransition metalschelatorsnitritesuperoxideperoxideslupinecytochrome b5 reductaseEC 1.6.2.2flavoproteinsoybeanflavin adenine dinucleotideprosthetic groupKcat/Kmdihydrolipoamide dehydrogenaseEC 1.8.1.4pyruvate dehydrogenase complexsignal peptidetransit peptidecowpeadomainNAD(P)+ transhydrogenase (Si-specific)NAD(P)+ transhydrogenase (Re/Si-specific)Methemoglobin reductaseNADPH—hemoprotein reductaseCytochrome P450 reductaseNADPH—cytochrome-c2 reductaseOxygenNADPH oxidaseP91-PHOXNeutrophil cytosolic factor 1Neutrophil cytosolic factor 2Neutrophil cytosolic factor 4Dual oxidase 1Dual oxidase 2QuinoneNADH dehydrogenaseNitrogenousTrimethylamine-N-oxide reductaseNADH dehydrogenase (quinone)EnzymesActive siteBinding siteCatalytic triadOxyanion holeEnzyme promiscuityDiffusion-limited enzymeCofactorEnzyme catalysisAllosteric regulationCooperativityEnzyme inhibitorEnzyme activatorEC numberEnzyme superfamilyEnzyme familyList of enzymesEnzyme kineticsEadie–Hofstee diagramHanes–Woolf plotLineweaver–Burk plotMichaelis–Menten kineticsTransferasesHydrolasesLyasesIsomerasesLigasesTranslocases