Optimization of a halophilic PHB depolymerase for industrial applications

Abstract

The present invention relates to a method for treatment of poly hydroxy alkanoate (PHA) containing post-consumer product, the method comprising contacting a post-consumer product with a polypeptide that can catalyze degradation of the PHA, the contact taking place at a temperature at least 40° C. and in the presence of salt at a concentration of 1 M or greater. In a specific embodiment, the polypeptide is a wild-type PHA depolymerase expressed by a halophilic microorganism or a modified PHA depolymerase that includes one or more single-site mutations as compared to the wild-type PHA depolymerase. In another specific embodiment, the polypeptide comprising a modified poly hydroxy butyrate (PHB) depolymerase comprising one or more single-site mutations as compared to SEQ ID NO: 1, and the modified PHB depolymerase having a solubility of 10 mg/L or greater. The present invention also relates to a host cell transformed to express a polypeptide that catalyzes degradation of a PHA in the presence of salt at a concentration of 1 M or greater, wherein the host cell is selected from an E. coli cell or a halophilic microorganism.

Dependencies are inferred from the claim text.