UniProt functional annotation for Q56268



	UniProt functional annotation for Q56268

UniProt code: Q56268.

Organism: Acidithiobacillus ferrooxidans (Thiobacillus ferrooxidans).

Taxonomy: Bacteria; Proteobacteria; Acidithiobacillia; Acidithiobacillales; Acidithiobacillaceae; Acidithiobacillus.

Function: Catalyzes the oxidation of 3-carboxy-2-hydroxy-4- methylpentanoate (3-isopropylmalate) to 3-carboxy-4-methyl-2- oxopentanoate. The product decarboxylates to 4-methyl-2 oxopentanoate. Can also use D-malate and L-malate, with lower efficiency. {ECO:0000269|PubMed:8282728}.

Catalytic activity: Reaction=(2R,3S)-3-isopropylmalate + NAD(+) = 4-methyl-2-oxopentanoate + CO2 + NADH; Xref=Rhea:RHEA:32271, ChEBI:CHEBI:16526, ChEBI:CHEBI:17865, ChEBI:CHEBI:35121, ChEBI:CHEBI:57540, ChEBI:CHEBI:57945; EC=1.1.1.85; Evidence={ECO:0000255|HAMAP- Rule:MF_01033, ECO:0000269|PubMed:8282728};

Cofactor: Name=Mg(2+); Xref=ChEBI:CHEBI:18420; Evidence={ECO:0000255|HAMAP-Rule:MF_01033}; Name=Mn(2+); Xref=ChEBI:CHEBI:29035; Evidence={ECO:0000255|HAMAP-Rule:MF_01033}; Note=Binds 1 Mg(2+) or Mn(2+) ion per subunit. {ECO:0000255|HAMAP- Rule:MF_01033};

Activity regulation: The presence of K(+) or NH4(+) is essential for activity. {ECO:0000269|PubMed:8282728}.

Biophysicochemical properties: Kinetic parameters: KM=26 uM for 3-isopropylmalate {ECO:0000269|PubMed:8282728}; KM=0.8 mM for NAD {ECO:0000269|PubMed:8282728}; KM=4 mM for D-malate {ECO:0000269|PubMed:8282728}; KM=12 mM for L-malate {ECO:0000269|PubMed:8282728}; pH dependence: Optimum pH is 9.0. {ECO:0000269|PubMed:8282728}; Temperature dependence: Optimum temperature is 60 degrees Celsius. {ECO:0000269|PubMed:8282728};

Pathway: Amino-acid biosynthesis; L-leucine biosynthesis; L-leucine from 3-methyl-2-oxobutanoate: step 3/4. {ECO:0000255|HAMAP- Rule:MF_01033}.

Subunit: Homodimer. {ECO:0000255|HAMAP-Rule:MF_01033, ECO:0000269|PubMed:8282728, ECO:0000269|PubMed:9739088}.

Subcellular location: Cytoplasm {ECO:0000255|HAMAP-Rule:MF_01033}.

Similarity: Belongs to the isocitrate and isopropylmalate dehydrogenases family. LeuB type 1 subfamily. {ECO:0000255|HAMAP- Rule:MF_01033, ECO:0000305}.

Annotations taken from UniProtKB at the EBI.


Organism:		Acidithiobacillus ferrooxidans (Thiobacillus ferrooxidans).
Taxonomy:		Bacteria; Proteobacteria; Acidithiobacillia; Acidithiobacillales; Acidithiobacillaceae; Acidithiobacillus.



Function:		Catalyzes the oxidation of 3-carboxy-2-hydroxy-4- methylpentanoate (3-isopropylmalate) to 3-carboxy-4-methyl-2- oxopentanoate. The product decarboxylates to 4-methyl-2 oxopentanoate. Can also use D-malate and L-malate, with lower efficiency. {ECO:0000269\|PubMed:8282728}.


Catalytic activity:		Reaction=(2R,3S)-3-isopropylmalate + NAD(+) = 4-methyl-2-oxopentanoate + CO2 + NADH; Xref=Rhea:RHEA:32271, ChEBI:CHEBI:16526, ChEBI:CHEBI:17865, ChEBI:CHEBI:35121, ChEBI:CHEBI:57540, ChEBI:CHEBI:57945; EC=1.1.1.85; Evidence={ECO:0000255\|HAMAP- Rule:MF_01033, ECO:0000269\|PubMed:8282728};
Cofactor:		Name=Mg(2+); Xref=ChEBI:CHEBI:18420; Evidence={ECO:0000255\|HAMAP-Rule:MF_01033}; Name=Mn(2+); Xref=ChEBI:CHEBI:29035; Evidence={ECO:0000255\|HAMAP-Rule:MF_01033}; Note=Binds 1 Mg(2+) or Mn(2+) ion per subunit. {ECO:0000255\|HAMAP- Rule:MF_01033};
Activity regulation:		The presence of K(+) or NH4(+) is essential for activity. {ECO:0000269\|PubMed:8282728}.
Biophysicochemical properties:		Kinetic parameters: KM=26 uM for 3-isopropylmalate {ECO:0000269\|PubMed:8282728}; KM=0.8 mM for NAD {ECO:0000269\|PubMed:8282728}; KM=4 mM for D-malate {ECO:0000269\|PubMed:8282728}; KM=12 mM for L-malate {ECO:0000269\|PubMed:8282728}; pH dependence: Optimum pH is 9.0. {ECO:0000269\|PubMed:8282728}; Temperature dependence: Optimum temperature is 60 degrees Celsius. {ECO:0000269\|PubMed:8282728};
Pathway:		Amino-acid biosynthesis; L-leucine biosynthesis; L-leucine from 3-methyl-2-oxobutanoate: step 3/4. {ECO:0000255\|HAMAP- Rule:MF_01033}.
Subunit:		Homodimer. {ECO:0000255\|HAMAP-Rule:MF_01033, ECO:0000269\|PubMed:8282728, ECO:0000269\|PubMed:9739088}.
Subcellular location:		Cytoplasm {ECO:0000255\|HAMAP-Rule:MF_01033}.
Similarity:		Belongs to the isocitrate and isopropylmalate dehydrogenases family. LeuB type 1 subfamily. {ECO:0000255\|HAMAP- Rule:MF_01033, ECO:0000305}.