FIG 1.
Construction of pUDH and pUFH plasmids. (A) Primers SalI-HMG-CoA-Up and KpnI-HMG-CoA-Do were used to amplify hmgPf from the vector pLC70 (20). pUD and HMG-CoA were digested by SalI (S) and BamHI (B) and were then ligated to obtain the plasmid pUDH. (B) Primers XhoI-pyrF-TB-Up and XmaISmaI-pyrF-TB-Do were used to amplify the T. barophilus pyrF gene. pUDH and pyrF(TB) were digested by XhoI (X) and SmaI (S) and were then ligated to obtain the plasmid pUFH. In pUDH and pUFH, the restriction enzyme sites BamHI (B) and KpnI (K) were conserved to enable cloning of the homologous regions in these plasmids.