In 1989, Sinskey and Peoples identified the location of phbA and phbB genes on plasmid, a single helix double-stranded loop DNA that can replicate independently of the chromosomal DNA, pAeT29 of E. coli and found that their expressions were under the control of Alcaligenes eutrophus promoter. Later in the same year, the two researchers mapped the location of phbC— the phbC gene is located upstream from phbA-phbB (Figure 2). Additionally, they also observed reduced activities in both thiolase and reeducate. Their results suggest that in PHB2 and PHB3 strains, all three genes are expressed from the same promoter located upstream from phbC