Construction of a stable plasmid vector for industrial production of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) by a recombinant Cupriavidus necator H16 strain

摘要

A new stable plasmid vector (pCUP3) was developed for high and stable production of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH) using Cupriavidus necator H16 as the host strain-In pCUP3, it was found that the plasmid partition and replication region of the megaplasmid pMOL28 in the Cupriavidus metallidurans CH34 strain plays an important role in plasmid stability in C necator H16. Moreover, the partition locus (comprising parA2S and parB28 and the parS28 region) is essential for plasmid maintenance under high-PHBH-accumulation. PHBH productivity by the "C necator H16/ds strain (phaCI deactivated mutant strain) harboring a phaCnc NSDG within pCUP3 was identical to the productivity of poly(3-hydroxybutyrate) by the C necator H16 strain when palm kernel oil was used as the sole carbon source without any antibiotics. This new vector is important for industrial mass production of polyhydroxyalkanoates using the C necator H16 strain as the host, dispensing the necessity of the application of selective pressure such as antibiotics.