Fig. 1.

Generation of homoplastomic plants expressing OspA:YFP fusion protein. a Sequences coding for YFP were fused with the one coding for OspA and placed between psbA 5′- and 3′-untranslated regions and subsequently cloned into the pRB95 vector (Ruf et al. 2001) to integrate the transgenes between trnfM and trnG of the tobacco plastomic region. b Southern blot analysis of plants to confirm the correct integration of transgenes at the chosen site and prove homoplastomy. Genomic DNA was isolated, digested with Eco01091 and hybridized with a digoxigenin-labelled probe corresponding to the flanking region of the plastome amplified from wild type. Fragment sizes shown are in kb. c Immunoblot analysis of proteins from OA14:YFP transplastomic plants carried out using an anti-OspA antibody. Recombinant OspA purified from E. coli was used as standards for quantification. Amounts of total protein loaded indicated. The level of OspA-YFP fusion expressed in 1,000 ng of TSP was equivalent to approximately 50 ng of the OspA standard. d Phenotype of plants expressing OspA-YFP fusion protein compared to wild type