Crystal Structure of Poly(Aspartic Acid) Hydrolase‐1

Abstract

Poly(aspartic acid) (PAA) is a biodegradable synthetic polymer that is easily produced through heating aspartic acid followed by the subsequent addition of sodium hydroxide. Polymer applications range from drug delivery and biomimetics to hygiene products. Partial biodegradation of PAA is accomplished using poly(aspartic acid) hydrolase‐1 (PAAH‐1) which selectively cleaves a specific cross‐link. E. coli expressions of recombinant PAAH‐1 showed the production of significant amounts of protein which could be purified using a single Ni‐NTA column. Analysis of the PAAH‐1 sequence using the Phyre2 Protein Fold Recognition Server resulted in a 33% similarity to a “putative” poly(3‐hydroxybutyrate) depolymerase belonging to a family of enzymes that hydrolyze carboxylic ester bonds; however, no known structure of PAAH‐1 has been reported. Protein crystallization screening at the Hauptman‐Woodward Research Institute resulted in numerous protein crystallization hits being identified. Crystallization experiments were optimized in‐house and the structure was determined at 2.45Å using molecular replacement. The progress of PAAH‐1 characterization and its structure will be discussed.Support or Funding InformationNSF‐IUSE Grant: DUE 1611988This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.