Each mutation was moved individually into FA
production strain BE1576 and its effect on fermentative FA
production was tested (Fig. 5). Deletion of the tesB, paaI or
ybgC genes had little effect on the fermentative production
of FA. However, deletion of the yciA gene substantially
decreased butyrate formation while increasing hexanoate
formation. This suggested that YciA plays a significant role
in the hydrolysis of butyryl-CoA to butyrate.