Relative NucB protein level in P. bryantii TC1-1 cultures harboring pRH3 constructs containing start codon upstream sequences in which SD sequences form part of a secondary structures with different stabilities.

The nucB mRNA amount is relative to the amount expressed from the wild type nucB plasmid construct. Protein level measurements using western blot were performed at least three times except in the case of constructs 5,2 and 11,1 for which six and five measurements respectively were made.