Figure 1.

Comparison of the structures of the cmp-genomic region in WT and in the M42 (ΔcmpAB∷kan^r) and CMP+ (PnirA∷cmpABCD) mutants of Synechococcus sp. strain PCC7942. The bar above the map shows the probe region used for Northern hybridization analysis. The open bars represent the antibiotic-resistance gene cassettes and the hatched bars show the location and orientation of the kanamycin-resistance gene (npt) and the spe^r gene (aad). The restriction endonuclease sites are abbreviated as follows: B, BglII; N, NcoI; P, PstI; Sa, SalI; Sp, SphI; and X, XbaI.