There are two genes, fabI1 and fabI2 (UniProt AC: Q57A95 and Q57EU5), annotated as encodes putative enoyl-ACP reductase in Brucella abortus genome. Sequence alignment found that BaFabI1 and BaFabI2 are 50% and 51% identical to E. coli FabI, respectively. Further analysis identified that the catalytically active triad (Tyr-(Xaa)₆-Lys) of E. coli FabI are present in both BaFabI1 and BaFabI2. Expression of either of the two proteins restores the growth and the fatty acid synthesis of the E. coli fabI temperature sensitive mutant JP1111 under nonpermissive condition. In vitro assay identifies that both proteins restore the fatty acid synthetic ability and are active with substrates of all fatty acid chain lengths. These results demonstrated that B. abortus possesses two FabI-like enoyl-ACP reductases and it represents a new kind of diversity of bacterial enoyl-ACP reductase.