TABLE 1.

POR activity of PORGDAB expressed in E. colia

CompoundSp act (nmol/min/mg of protein)
JVQ2:pBSKPORAB1157:pPBSKPOR
NTZ3,325 ± 4282,233 ± 117
Nitrofurazone41.2 ± 5.437.9 ± 1.5
Nitrofurantoin29.2 ± 4.121.4 ± 0.6
Furazolidone25.6 ± 1.718.1 ± 0.4
MTZ<0.1<0.1
  • a The E. coli strains used in this study are AB1157 (wild type) and JVQ2nfsAnfsB (deficient in nitroreductase activity). Plasmid pPORGDAB contains the POR operon in pBSK. Enzyme activities were determined under anaerobic conditions at the appropriate wavelength for each compound as detailed in the text.