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SIRT1 top 40 hits: use of one-bead, one-compound acetyl-peptide libraries and quantum dots to probe deacetylase specificity.

ABSTRACT: A novel, high-throughput method for determining deacetylase substrate specificity was developed using a one-bead, one-compound (OBOC) acetyl-peptide library with a quantum dot tagging strategy and automated bead-sorting. A 5-mer OBOC peptide library of 104,907 unique sequences was constructed around a central epsilon-amino acetylated lysine. The library was screened using the human NAD+-dependent deacetylase SIRT1 for the most efficiently deacetylated peptide sequences. Beads preferentially deacetylated by SIRT1 were biotinylated and labeled with streptavidin-coated quantum dots. After fluorescent bead-sorting, the top 39 brightest beads were sequenced by mass spectrometry. In-solution deacetylase assays on randomly chosen hit and nonhit sequences revealed that hits correlated with increased catalytic activity by as much as 20-fold. We found that SIRT1 can discriminate peptide substrates in a context-dependent fashion.

SUBMITTER: Garske AL

PROVIDER: S-EPMC2519118 | biostudies-literature | 2006 Jan

REPOSITORIES: biostudies-literature

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SIRT1 top 40 hits: use of one-bead, one-compound acetyl-peptide libraries and quantum dots to probe deacetylase specificity.

Garske Adam L AL Denu John M JM

Biochemistry 20060101 1

A novel, high-throughput method for determining deacetylase substrate specificity was developed using a one-bead, one-compound (OBOC) acetyl-peptide library with a quantum dot tagging strategy and automated bead-sorting. A 5-mer OBOC peptide library of 104,907 unique sequences was constructed around a central epsilon-amino acetylated lysine. The library was screened using the human NAD+-dependent deacetylase SIRT1 for the most efficiently deacetylated peptide sequences. Beads preferentially deac ...[more]

PMID: 16388584

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