Molecular Cloning and Expression of Human L-Pipecolate Oxidase

• Published in: Biochemical and biophysical research communications Vol. 270; no. 3; pp. 1101 - 1105
• Main Authors: IJlst, Lodewijk, de Kromme, Isabella, Oostheim, Wendy, Wanders, Ronald J.A.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 21.04.2000
• Subjects: Amino Acid Sequence; amino acids; Animals; Base Sequence; Binding Sites; Cloning, Molecular; Escherichia coli; Flavoproteins - chemistry; Flavoproteins - genetics; Flavoproteins - metabolism; Haplorhini; Humans; hyperpipecolic acidemia; L-pipecolate oxidase; lysine; Lysine - metabolism; Molecular Sequence Data; Oxidoreductases Acting on CH-NH Group Donors - chemistry; Oxidoreductases Acting on CH-NH Group Donors - genetics; Oxidoreductases Acting on CH-NH Group Donors - metabolism; peroxisomal disorders; peroxisomes; pipecolic acid; Pipecolic Acids - metabolism; Polymerase Chain Reaction; Protein Folding; Recombinant Proteins - chemistry; Recombinant Proteins - metabolism; Sarcosine Oxidase; pipecolic acid; peroxisomes; peroxisomal disorders; amino acids
• ISSN: 0006-291X; 1090-2104
• DOI: 10.1006/bbrc.2000.2575

In higher eukaryotes L-lysine can be degraded via two distinct routes including the saccharopine pathway and the L-pipecolate pathway. The saccharopine pathway is the primary route of degradation of lysine in most tissues except the brain in which the L-pipecolate pathway is most active. L-pipecolate is formed from L-lysine via two enzymatic reactions and then undergoes dehydrogenation to Δ1-piperideine-6-carboxylate. At least in humans and monkeys, this is brought about by the enzyme L-pipecolate oxidase (PIPOX) localized in peroxisomes. In literature, several patients have been described with hyperpipecolic acidaemia. The underlying mechanism responsible for the impaired degradation of pipecolate has remained unclear through the years. In order to resolve this question, we have now cloned the human L-pipecolate oxidase cDNA which codes for a protein of 390 amino acids and contains an ADP-βαβ-binding fold compatible with its identity as a flavoprotein. Furthermore, the deduced protein ends in −KAHL at its carboxy terminus which constitutes a typical Type I peroxisomal-targeting signal (PTS I).