Nucleotide sequence of Salmonella typhimurium nitroreductase gene

'Classical nitroreductase' is an enzyme involved in theintracellular metabolic activation ofmutagenic nitroarenes (1).Wehave already cloned the nitroreductase gene ofSalmonellatyphimuriumTA1538(2) anddeterminedthenucleotide sequenceby dideoxy sequence analysis ofboth strands. Below is shownthe nucleotide sequence of 1690base fragment which containsanopenreadingframeof651 nucleotides withpotential to encodethe nitroreductase. Themaxicell technique wasusedto identifythe nitroreductase and its molecular weight was estimated as28KDa, which is close to the calculated molecular weight of23,955. Possible sequence of -35, -10, S.D. and rho-independent transcriptional termination signal are indicated.