TY - JOUR
T1 - Biotinyl-methyl 4-(amidomethyl)benzoate is a competitive inhibitor of human biotinidase
AU - Kobza, Keyna A.
AU - Chaiseeda, Kittichai
AU - Sarath, Gautam
AU - Takacs, James M.
AU - Zempleni, Janos
N1 - Funding Information:
This study was a contribution of the University of Nebraska Agricultural Research Division and was supported in part by funds provided through the Hatch Act. Additional support was provided by NIH Grants DK 063945 and ES 015206, USDA Grant 2006-35200-17138 and by NSF EPSCoR Grants EPS-0346476 and EPS-0701892.
PY - 2008/12
Y1 - 2008/12
N2 - Posttranslational modification of histones by biotinylation can be catalyzed by both biotinidase (BTD) and holocarboxylase synthetase. Biotinylation of histones is an important epigenetic mechanism to regulate gene expression, DNA repair, and chromatin remodeling. The role of BTD in histone biotinylation is somewhat ambiguous, given that BTD also catalyzes removal of the biotin tag from histones. Here, we sought to develop BTD inhibitors for future studies of the role of BTD in altering chromatin structure. We adopted an existing colorimetric BTD assay for use in a novel 96-well plate format to permit high-throughput screening of potential inhibitors. Biotin analogs were chemically synthesized and tested for their ability to inhibit human BTD. Seven of these compounds inhibited BTD by 26-80%. Biotinyl-methyl 4-(amidomethyl)benzoate had the largest effect on BTD, causing an 80% inhibition at 1 mM concentration. Enzyme kinetics studies were conducted to determine Vmax, Km and Ki for the seven inhibitors; kinetics were consistent with the hypothesis that biotinyl-methyl 4-(amidomethyl)benzoate and the other compounds acted by competitive inhibition of BTD. Finally, biotinyl-methyl 4-(amidomethyl)benzoate did not affect biotin transport in human cells, suggesting specificity in regard to biotin-related processes.
AB - Posttranslational modification of histones by biotinylation can be catalyzed by both biotinidase (BTD) and holocarboxylase synthetase. Biotinylation of histones is an important epigenetic mechanism to regulate gene expression, DNA repair, and chromatin remodeling. The role of BTD in histone biotinylation is somewhat ambiguous, given that BTD also catalyzes removal of the biotin tag from histones. Here, we sought to develop BTD inhibitors for future studies of the role of BTD in altering chromatin structure. We adopted an existing colorimetric BTD assay for use in a novel 96-well plate format to permit high-throughput screening of potential inhibitors. Biotin analogs were chemically synthesized and tested for their ability to inhibit human BTD. Seven of these compounds inhibited BTD by 26-80%. Biotinyl-methyl 4-(amidomethyl)benzoate had the largest effect on BTD, causing an 80% inhibition at 1 mM concentration. Enzyme kinetics studies were conducted to determine Vmax, Km and Ki for the seven inhibitors; kinetics were consistent with the hypothesis that biotinyl-methyl 4-(amidomethyl)benzoate and the other compounds acted by competitive inhibition of BTD. Finally, biotinyl-methyl 4-(amidomethyl)benzoate did not affect biotin transport in human cells, suggesting specificity in regard to biotin-related processes.
KW - Biotinidase
KW - Biotinyl-methyl 4-amidomethyl benzoate
KW - Histones
KW - Inhibitors
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U2 - 10.1016/j.jnutbio.2007.11.002
DO - 10.1016/j.jnutbio.2007.11.002
M3 - Article
C2 - 18479898
AN - SCOPUS:55249120729
SN - 0955-2863
VL - 19
SP - 826
EP - 832
JO - Journal of Nutritional Biochemistry
JF - Journal of Nutritional Biochemistry
IS - 12
ER -