Dibenzothiophene (DBT) and its derivatives comprise up to 60% of the organosulfur contamination of crude oil. The enzyme 2‐(2′‐hydroxyphenyl)benzenesulfinate desulfinase (DszB) catalyzes the carbon‐sulfur bond cleavage in the final, and rate‐limiting step in the biodesulfurization of DBT. The wildtype dszb genes from Nocardia asteroides A3H1 (A3H1) and Rhodococcus erythropolis IGTS8 (IGTS8) were expressed with and without chaperone proteins under different induction conditions. Yield of active enzyme was optimal when co‐expressed in E. coli in the presence of GroEL and GroES. Codon optimized dszb genes were synthesized, optimizing E. coli codon usage and minimizing GC content. The codon optimized dszb genes from A3H1 and IGTS8 were expressed with and without chaperone proteins under different induction conditions. GroEL and GroES were both still required for optimal enzyme activity. Protein aggregation was observed using whole cell FT‐IR spectroscopy in all cases, but was significantly larger in induced cells in the absence of chaperones.Support or Funding Information NSF CHE 1461175 James Madison University Department of Chemistry and Biochemistry This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.