DNA degradation is a key post-cell death process driven by the Dnase1 family of endonucleases. The activity of one such enzyme, Dnase1L3, is known to prevent the onset of Systemic Lupus Erythematosus (SLE), but its catalytic mechanism remains disputed. Computational analysis implicates two histidines as catalytically necessary, but an in vitro comparison of the activity of proteins possessing and lacking these histidines has not been conducted to date.

 This project is new this year and was piloted by a Pingry senior last year. This year, we will reproduce their results and build from there.

In the upcoming year, we are going to develop a preliminary assay to test the enzymatic activity of PETase. This assay may include either a plate-clearing assay using E. coli cells or an in-vitro hydrolase assay. By establishing the baseline of enzymatic activity for our variants of PETase, we will be able to compare their activity to future PETase variants. Through transforming, inducing, purifying, and conducting activity assays, our project aims to compare the catalytic activity of Dnase1L3 animal homologs (owl monkey and box turtle) with human Dnase1L3.

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