Cloning and characterization of a pyridoxine 5'-phosphate oxidase from silkworm, Bombyx mori
2009
Huang, S-H. | Shi, R-J. | Zhang, J-Y. | Wang, Z. | Huang, L-Q.
A cDNA encoding Pyridoxine 5'-phosphate oxidase (PNPO) from Bombyx mori was cloned and characterized (G enB ank accession number: DQ452398). The cDNA encodes a polypeptide of 257 amino acid residues. The recombinant enzyme purified from Escherichia coli exhibited maximal activity at pH 9.0, and the Km values for the substrates of pyridoxine 5'-phosphate and pyridoxamine 5'-phosphate were determined as 0.65 and 1.15 μmol/l. It was found that B. mori PNPO shares 51.44% homology with humans, but several function-related, key amino acid residues in B. mori PNPO are different from the human and E. Coli gene. B. mori has a single copy of the PNPO gene, which spans a 3.5 kb region and contains five exons and four introns. B. mori PNPO is a homodimer, with each monomer containing nine antiparallel β-strands and five α-helical segments. The secondary structure was deduced from computational study.
Show more [+] Less [-]AGROVOC Keywords
Bibliographic information
This bibliographic record has been provided by National Agricultural Library