FIG. 4.
Expression of P. furiosus CbtA in E. coli SF120/1244. (A) Cellobiose binding activity at 37°C (white bars) and 60°C (black bars) using 500 nM [3H]cellobiose. (B) Western blot detection of His6-CbtA by using His antibodies in the membrane (mem) and supernatant (sup) of cell lysates after (+) and before (−) induction. The E. coli SF120/1244 cells that were used were cotransformed with p1244, which harbors the rare tRNA genes, and pET302 (empty vector) or pSMK4, which contains the cbtA gene with an N-terminal hexahistidine tag.