Biotinidase, Recombinant, Human, aa42-543 (BTD)

Biotinidase (BTD) is a member of the nitrilase superfamily, which consists of 12 families of nitrilases, amidases, carbamylases, and N­acyltrasferases (1). It is a thiol hydrolase releasing biotin from biotinamide, biotin­lysine, biotin­peptide conjugates and biotin methylester. It is expressed in most mammalian tissues, with high activity being present in liver, kidney, serum, intestine, and adrenal glands (2). BTD with two other proteins, sodium­dependent multivitamin transporter, and holocarboxylase synthetase, play major roles in the homeostasis of biotin (3). BTD contributes to the homeostasis through the intestinal release of free biotin from digested biotin­containing proteins and plasma transport and the recycling of biotin from breakdown products of biotinylated carboxylases. BTD deficiency can lead to a decrease in biotin bioavailability due to failure in releasing biotin from dietary proteins. It can be caused by gene mutations or from decreased secretion of BTD into the intestinal lumen (4). A recent study indicates that the BTD level in human plasma is a potential biomarker for the detection of breast cancer (5). Recombinant protein corresponding to aa42-543 human beta-NGF (UniProt Accession #P43251), CHO-derived , Molecular Weight:, 65-80kD (by SDS-PAGE, reducing conditions), 58kD (predicted), Activity: Measured by its ability to hydrolyze biocytin to lysine and biotin. The specific activity is >700pmol/min/ug, as measured under the described conditions. See Activity Assay Protocol. Storage and Stability: Aliquot to avoid repeated freezing and thawing and store at -70°C. Aliquots are stable for 6 months. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap.