• Journal of Microbiology and Biotechnology
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• v.16 no.9
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• pp.1468-1471
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• 2006

The last step in L-carnitine biosynthesis in eukaryotic organisms is mediated by ${\gamma}$-butyrobetaine hydroxylase (EC1.14.11.1), a dioxygenase that converts ${\gamma}$-butyrobetaine to L-carnitine. This enzyme was previously identified from rat liver and humans, and the peptide sequence of human ${\gamma}$-butyrobetaine hydroxylase was used to search the Neurospora crassa genome database, which led to an identification of an open reading frame (ORF) consisting of 1,407 bp encoding a polypeptide of 468 amino acids. When this protein was expressed in Saccharomyces cerevisiae, the crude cell-free extract exhibited ${\gamma}$-butyrobetaine hydroxylase activity.