Article

You have free access to this content

Biosynthesis of polylactic acid and its copolymers using evolved propionate CoA transferase and PHA synthase

  1. Taek Ho Yang1,
  2. Tae Wan Kim1,
  3. Hye Ok Kang1,
  4. Sang-Hyun Lee1,
  5. Eun Jeong Lee1,
  6. Sung-Chul Lim1,
  7. Sun Ok Oh1,
  8. Ae-Jin Song2,
  9. Si Jae Park1,*,
  10. Sang Yup Lee2,3,*

Article first published online: 23 NOV 2009

DOI: 10.1002/bit.22547

Issue

Biotechnology and Bioengineering

Biotechnology and Bioengineering

Volume 105, Issue 1, pages 150–160, 1 January 2010

Additional Information

How to Cite

Yang, T. H., Kim, T. W., Kang, H. O., Lee, S.-H., Lee, E. J., Lim, S.-C., Oh, S. O., Song, A.-J., Park, S. J. and Lee, S. Y. (2010), Biosynthesis of polylactic acid and its copolymers using evolved propionate CoA transferase and PHA synthase. Biotechnol. Bioeng., 105: 150–160. doi: 10.1002/bit.22547

Author Information

  1. 1

    Corporate R&D, LG Chem Research Park, 104-1 Moonji-dong, Yuseong-gu, Daejeon 305-380, Republic of Korea; telephone: +82-42-870-6442; fax: +82-42-861-2057

  2. 2

    Metabolic and Biomolecular Engineering National Research Laboratory, Department of Chemical and Biomolecular Engineering (BK21 Program), Center for Systems and Synthetic Biotechnology, and Institute for the BioCentury, KAIST, 335 Gwahangno, Yuseong-gu, Daejeon 305-701, Republic of Korea; telephone: +82-42-350-3930; fax: +82-42-350-3910

  3. 3

    Department of Bio and Brain Engineering, Department of Biological Sciences, BioProcess Engineering Research Center, and Bioinformatics Research Center, KAIST, 335 Gwahangno, Yuseong-gu, Daejeon 305-701, Republic of Korea

*Corporate R&D, LG Chem Research Park, 104-1 Moonji-dong, Yuseong-gu, Daejeon 305-380, Republic of Korea; telephone: +82-42-870-6442; fax: +82-42-861-2057.

Publication History

  1. Issue published online: 23 NOV 2009
  2. Article first published online: 23 NOV 2009
  3. Manuscript Accepted: 14 SEP 2009
  4. Manuscript Revised: 5 SEP 2009
  5. Manuscript Received: 26 JUL 2009

Funded by

  • LG Chem
  • Korean Systems Biology Research Project of the Ministry of Education, Science and Technology through Korea Science and Engineering Foundation
  • World Class University Program of the Ministry of Education, Science and Technology. Grant Number: 20090065571

SEARCH

SEARCH BY CITATION

ARTICLE TOOLS

Get PDF (462K)

Keywords:

  • polylactic acid;
  • PLA;
  • PHA synthase;
  • propionate CoA transferase;
  • enzyme evolution

Abstract

For the synthesis of polylactic acid (PLA) and its copolymers by one-step fermentation process, heterologous pathways involving Clostridium propionicum propionate CoA transferase (PctCp) and Pseudomonas sp. MBEL 6-19 polyhydroxyalkanoate (PHA) synthase 1 (PhaC1Ps6-19) were introduced into Escherichia coli for the generation of lactyl-CoA endogenously and incorporation of lactyl-CoA into the polymer, respectively. Since the wild-type PhaC1Ps6-19 did not efficiently accept lactyl-CoA as a substrate, site directed mutagenesis as well as saturation mutagenesis were performed to improve the enzyme. The wild-type PctCp was not able to efficiently convert lactate to lactyl-CoA and was found to exert inhibitory effect on cell growth, random mutagenesis by error-prone PCR was carried out. By employing engineered PhaC1Ps6-19 and PctCp, poly(3-hydroxybutyrate-co-lactate), P(3HB-co-LA), containing 20–49 mol% lactate could be produced up to 62 wt% from glucose and 3HB. By controlling the 3HB concentration in the medium, PLA homopolymer and P(3HB-co-LA) containing lactate as a major monomer unit could be synthesized. Also, P(3HB-co-LA) copolymers containing various lactate fractions could be produced from glucose alone by introducing the Cupriavidus necator β-ketothiolase and acetoacetyl-CoA reductase genes. Fed-batch cultures were performed to produce P(3HB-co-LA) copolymers having 9–64 mol% of lactate, and their molecular weights, thermal properties, and melt flow properties were determined. Biotechnol. Bioeng. 2010; 105: 150–160. © 2009 Wiley Periodicals, Inc.

Get PDF (462K)