Our first focus will be in improving the production and purification of the produced DCD-1L, the primary challenge being to remove the Smt3 fragment and the Ulp1 from the solution after the cleavage step. One way to remove the Smt3 is by affinity chromatography since it is still attached to the His-tag, and thus it could be easily removed. After this step, to remove Ulp1, we could use filtration method to obtain the pure cleaved DCD-1L peptide. Standardizing this system will benefit many of the other different peptide productions done by this method as well.
Another immediate focus would be to test the antimicrobial activity of the pure DCD-1L alone and with the cellulose binding domain against P. acnes in a biosafety level 2 laboratory as this would support our application idea of using DCD-1L for acne treatment.
Previous studies state that DCD-1L has a wide range of antimicrobial activity and that it is salt and pH insensitive. However, it would be interesting to study the antimicrobial activity of DCD-1L with the cellulose binding domain under different peptide concentrations and buffer conditions against E. coli and P. acnes. This is due to the fact that in our current study we could not observe any antimicrobial activity with the cellulose binding domain in NaPi buffer and with 100 μg/ml peptide concentration.
Further studies on the antimicrobial activity of DCD-1L against E. coli and P. acnes in hydrogels would be of importance to validate our application idea of using DCD-1L as hydrogel based creams.
Finally, antimicrobial activity of DCD-1L against E. coli and P. acnes with different concentrations of zinc ions could also be considered as previous studies state the importance of zinc ions in formation of the DCD-1L hexamer.