Figure 1: Conjugative transfer of plasmids from E. coli to P. tricornutum.
From: Designer diatom episomes delivered by bacterial conjugation
(a) Map of the plasmids p0521 and p0521s and their derivation from P. tricornutum scaffold 25. OriT, origin of transfer; URA3, gene encoding orotidine 5′-phosphate decarboxylase from S. cerevisiae, and ShBle, phleomycin-resistance cassette with P. tricornutum FcpF promoter and FcpA terminator. (b) Average number of P. tricornutum colonies obtained per conjugation for different ‘cargo’ plasmid variants of p0521s. Deletions of features indicated by Δ, pRL443 is the RP4 conjugative plasmid. (c) Maps of plasmids used to test the importance of the P. tricornutum- and yeast-derived regions. Plasmids pPtPuc1-4 differ in whether they have the P. tricornutum-derived region from p0521s (Pt R1R2, green) or the yeast-derived CEN6-ARSH4-HIS3 (yellow). Other plasmid features present in all four plasmids are described on the pPtPuc1 map. (d) Number of P. tricornutum colonies obtained after conjugation with the pPtPuc plasmids (‘cargo’ plasmids). Features of each plasmid are noted in the table under the figure (for example, the P. tricornutum-derived region from p0521S, Pt R1R2, or the yeast elements, CEN6-ARSH4-HIS3). Error bars denote one s.d. of the mean from at least three biological replicates per experiment.
