FIG. 1.

Heterocyst suppression by DNA fragments subcloned from cosmid 8E11. Each shuttle plasmid was conjugated into Anabaena strain PCC 7120, and the heterocyst phenotype was determined. Phenotypes were scored as wild type (WT), heterocyst suppression (Het^s), and abnormal heterocyst pattern (Pat). Only selected restriction sites are shown. Symbols: arrows over ORF, direction of transcription; P with arrow, external promoter; inverted triangle, insertion of Ω Sp^r/Sm^r cassette; A, AccI; B, BamHI; C, ClaI; H, HincII; P, PacI; S, ScaI; T, TaqI; X, XbaI.