Biosynthesis of polyhydroxyalkanoates in recombinant Ralstonia eutropha

engineered to utilize sucrose as a carbon source

Si Jae Parka, Young Hoon Ohb, Jung Eun Yangc, So Young Choic, Seung Hwan Leeb, Sang Yup Leec

aDepartment of Environmental Engineering and Energy, Myongji University, Republic of Korea

bKorea Research Institute of Chemical Technology, Republic of Korea

cMetabolic and Biomolecular Engineering National Research Laboratory, Department of Chemical and Biomolecular Engineering (BK21 Program), KAIST, Republic of Korea

*Correspondence should be addressed to Sang Yup Lee (leesy@kaist.ac.kr) and Seung
Hwan Lee (hwanlee@krict.re.kr).

Polyhydroxyalkanoates (PHAs) are potential alternatives of petroleum-based polymers due to their material properties which are much similar to those of chemical plastics. Since the cost effective production of PHAs is one of the most important factors for the commercialization of PHAs, development of recombinant microorganisms able to efficiently utilize cheap carbon sources have been examined for the production of PHAs. Sucrose is one of the most abundant and least expensive carbon sources extracted from sugarcane and sugarbeet. Therefore, microorganisms capable of utilizing sucrose as carbon source might support cost-competitiveness of fermentation-driven products. Here, we report recombinant Ralstonia eutropha strains able to produce PHAs from sucrose as a carbon source. Sucrose utilization pathway was constructed in Ralstonia eutropha NCIMB11599 and R. eutropha 437-540 by introducing the Mannheimia succiniciproducens MBEL55E sacC gene encoding β-fructofuranosidase and was examined for the production of poly(3-hydroxybutyrate) [P(3HB)] and poly(3- hydroxybutyrate-co-lactate) [P(3HB-co-LA)], respectively. Detailed results will be presented in this presentation.

[This research was supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (NRF-2013R1A1A2058379) and by the Technology Development Program to Solve Climate Changes (Systems Metabolic Engineering for Biorefineries) from the Ministry
of Science, ICT and Future Planning through the NRF (NRF-2012-C1AAA001-
2012M1A2A2026556)].