4-Pyridoxolactonase from a symbiotic nitrogen-fixing bacterium Mesorhizobium loti: cloning, expression, and characterization.
4-Pyridoxolactonase is involved in the degradation pathway for pyridoxine, a free form of vitamin B6. The gene (mlr6805) encoding the putative 4-pyridoxolactonase of nitrogen fixing symbiotic microorganism Mesorhizobium loti MAFF303099 has been identified based on the genome database. The gene was cloned and overexpressed in a cotransformant Escherichia coli cell. The recombinant enzyme was dimeric protein and contained one mole of Zn2+ per mole of subunit. The enzyme showed about 30% identity with various N-acylhomoserine lactone lactonases and metallo-beta-lactamases. The phylogram made with ClustalW shows that 4-pyridoxolactonase makes a cluster with Agrobacterium tumefaciens acyl-homoserine lactone lactonase. The alignment of amino acid sequences suggests that 4-pyridoxolactonase has three histidine residues probably involved in binding of Zn2+.
Funami
Junichi
J
Department of Bioresources Science, Faculty of Agriculture, Kochi University, Monobe-Otsu 200, Nankoku, Kochi 783-8502, Japan.
Yoshikane
Yu
Y
Kobayashi
Hitoshi
H
Yokochi
Nana
N
Yuan
Baiqiang
B
Iwasaki
Kozo
K
Ohnishi
Kouhei
K
Yagi
Toshiharu
T
D016960:Agrobacterium tumefaciens / Q000201:enzymology / Q000235:genetics; D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism; D002265:Carboxylic Ester Hydrolases / Q000235:genetics* / Q000378:metabolism; D003001:Cloning, Molecular; D008969:Molecular Sequence Data; D010802:Phylogeny; D021122:Protein Subunits / Q000235:genetics / Q000378:metabolism; D012230:Rhizobiaceae / Q000201:enzymology* / Q000235:genetics; D020539:Sequence Analysis, Protein; D015032:Zinc / Q000378:metabolism
D001426:Bacterial Proteins; D021122:Protein Subunits; C050712:4-pyridoxolactonase; D002265:Carboxylic Ester Hydrolases; D015032:Zinc