Primary structure of pyridoxal k1nase from porcinh brain

The primary structure of pyridoxal kinase from porcine brain has been determined using ainino acid sequencing technique. A subunit of the dimeric enzyme lias been found to consist of 321 amino acid residues with a molecular mass of 36500 dallons. The N-terminal of each submit is blocked. According to previous report on the identification of the active site using polyphosphopyridoxyl adenosine as the affinity label, the site fragment peptide is located near the carboxylic acid end of the primary structure, spanning between 236 and 259 residues (VDAVFVGTGDLFAAMLLAWTHKHP) which is identical to those found in sheep brain. In comparison with the entire sequence from sheep brain, the porcine enzyme shares approximately 95% of the sequence homology indicating that the primary sequence of pyridoxal kinase is conserved. In our investigation, an additional sequence between 52 and 61 residues (QFSNHTGYAH) was found in porcine but not reported in the sheep brain enzyme structure. Since the primary sequence of pyridoxal kinase has been known, it is our further intention to elucidate the topographical structure of the enzyme using computer simulation technique and to clone the gene which encodes this enzyme.