US 12,447,514 B2 · Optimization of a thermophilic PHB depolymerase for industrial applications

Abstract

The present invention relates to a method for treatment of polyhydroxyalkanoate (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 45° C. In a specific embodiment, the poly peptide is a wild-type PHA depolymerase expressed by a thermophilic 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 an optimum temperature of at least 45° C. The present invention also relates to a host cell transformed to express a polypeptide that catalyzes degradation of a PHA, the polypeptide having an optimum temperature for the degradation reaction of at least 45° C., wherein the host cell is selected from an E. coli cell or a thermophilic microorganism.

Claims6

Dependent claims

A method for treatment of a post-consumer product, the method comprising:

contacting a post-consumer product with a polypeptide, the post-consumer product comprising a polyhydroxyalkanoate, the polypeptide catalyzing degradation of the polyhydroxyalkanoate, the contacting taking place at a temperature ef from 45° C. to 90° C.;
wherein the polypeptide comprises a modified polyhydroxyalkanoate depolymerase comprising the amino acid sequence of SEQ ID NO:
6 with the exception of at least one mutation at one or more position corresponding to position 3, 10, 15, 33, 41, 44, 49, 50, 62, 67, 78, 91, 92, 93, 97, 100, 102, 114, 122, 123, 124, 125, 127, 128, 129, 135, 139, 144, 145, 148, 152, 157, 159, 160, 167, 169, 184, 189, 200, 202, 206, 209, 233, 259, 260, 261, 269, and/or 275 of the amino acid sequence of SEQ ID NO:
6, wherein each mutation of the modified polyhydroxyalkanoate depolymerase independently has a DDG value of 1 kcal/mol or greater.

1 more element

Dependencies are inferred from the claim text.

Optimization of a thermophilic PHB depolymerase for industrial applications

Life of this patent

Optimization of a thermophilic PHB depolymerase for industrial applications

Life of this patent

Abstract

Claims6