Fig. 3

Comparison of the nucleotide sequences of the Ta genes from B. methanolicus PB1 and MGA3 as well as those of recreated MGA3 Ta genes. MGA3^put represents an alternative Ta coding sequence of MGA3. For MGA3^rec the ATA was changed to ATG and adjusted to that of PB1. For the variants M1-M6 the third codon of the sequence upstream of ta^MGA3 was changed from a stop TAA codon to different codons. The dashes indicate the same nucleotide as for PB1 and the dots show that the sequence continues. The red letters indicate a stop codon and the pink letter shows an additional nucleotide at that position. A rough screen showed that crude extracts of E. coli BL21 (DE3) expressing all of these proteins except for Ta^MGA3contained at least 20 mU/mg, i.e. two fold of the activity present in the parent strain (about 10 mU/mg)