dnaS or dut is a gene involved in DNA replication in Escherichia coli. It encodes dUTP nucleotidohydrolase, an enzyme responsible for catalyzing the conversion of dUTP to dUMP, thereby ensuring that the organism's DNA contains the nucleobase thymine instead of uracil.
See also
DUT, the human version of this gene dnaA dnaB dnaC dnaE dnaG dnaH dnaI dnaN dnaP dnaQ dnaX dnaZ
References