Figure 3

Overexpression of each candidate IBR in AL626. (A) Each candidate gene was cloned onto individual plasmids downstream of kivd (pAL213-pAL223) and introduced into AL626 (JCL260ΔyqhD ΔadhP ΔeutG ΔyiaY ΔyjgB ΔbetA ΔfucO) along with pGR03 (alsS, ilvC, and ilvD). Cells were grown at 37°C for 24 h. Titers represented as concentration per OD₆₀₀ to adjust for variations in growth. (B) Each gene was cloned onto individual plasmids and introduced into AL626. Cell extracts were assayed with acetaldehyde and isobutyraldehyde as substrates as well as with both cofactors (NADH & NADPH). Enzyme activity is defined as μmol NAD(P)H consumed per minute per mg of protein. NAD(P)H consumption measured at 340 nm. Error values represent the standard deviation of triplicate experiments. NA: not assayed. ND: not detectable.