Lactic acid bacterial (LAB) cells were modified such that they have a specific activity of dihydroxy-acid dehydratase enzyme activity that is increased to about 0.1 μmol min−1 mg−1. LAB cells with even higher activities of 0.2 to 0.6 μmol min−1 mg−1 of DHAD activity were obtained.These modified cells may be used to produce isobutanol when additional isobutanol biosynthetic pathway enzymes are expressed.