UDP-N-ACETYLGLUCOSAMINE 1-CARBOXYVINYL-TRANSFERASE FROM ACINETOBACTER-CALCOACETICUS

We have analyzed the sequence downstream of rpoN from Acinetobacter ca lcoaceticus and identified an open reading frame encoding a protein wi th high similarity to UDP-N-acetylglucosamine 1-carboxyvinyl-transfera se (MurZ). Multicopy plasmids encoding this enzyme conferred phosphomy cin resistance to A. calcoaceticus. The polar effect of a rpoN mutatio n on the phosphomycin resistance level suggests that murZ is, in part, cotranscribed with rpoN. These observations confirm that A. calcoacet icus represents the first exception from a conserved genetic context o f rpoN observed in several other Gram-negative bacteria.