| Autor: |
Hozumi, Yuka, Hachisuka, Shin-ichi, Tomita, Hiroya, Kikukawa, Hiroshi, Matsumoto, Ken’ichiro |
| Zdroj: |
Biomacromolecules; 20240101, Issue: Preprints |
| Abstrakt: |
Polyhydroxyalkanoate (PHA) synthases (PhaCs) are useful and versatile tools for the production of aliphatic polyesters. Here, the chimeric PHA synthase PhaCARwas engineered to increase its capacity to incorporate unusual 6-hydroxyhexanoate (6HHx) units. Mutations at positions 149 and 314 in PhaCARwere previously found to increase the incorporation of an analogous natural monomer, 3-hydroxyhexanoate (3HHx). We attempted to repurpose the mutations to produce 6HHx-containing polymers. Site-directed saturation mutants at these positions were applied for P(3HB-co-6HHx) synthesis in Escherichia coli. As a result, the N149D and F314Y mutants effectively increased the 6HHx fraction. Moreover, the pairwise NDFY mutation further increased the 6HHx fraction, which reached 22 mol %. This increase was presumably caused by altered enzyme activity rather than altered expression levels, as assessed based on immunoblot analysis. The glass transition temperature and crystallinity of P(3HB-co-6HHx) decreased as the 6HHx fraction increased. |
| Databáze: |
Supplemental Index |
| Externí odkaz: |
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