Expression of C. acetobutylicium FabF1 restores UFA synthesis to E. coli fabB strains. The methyl esters of fatty acids were obtained from the phospholipids as described in Methods. Lane 1 is the esters of the wild type E. coli strain MG1655. Lane 2 is the esters of strain CY242 carrying pHW36 (fabF1) in presence of arabinose induction. Lane 3 is the esters of strain CY242 carrying pHW36 (fabF1) in the absence of induction. Lane 4 is the esters of strain CY242 carrying vector pBAD24. The migration positions of the methyl esters of the fatty acid species are shown. The designations are: Sat, saturated fatty acid esterss; Δ9C16:1, methyl ester of cis-9-hexadecenoic; Δ11C18:1, methyl ester of cis-11-octadecenoic.