TY - JOUR
T1 - Metabolic engineering of Methylorubrum extorquens AM1 for poly (3-hydroxybutyrate-co-3-hydroxyvalerate) production using formate
AU - Yoon, Jihee
AU - Chang, Woojin
AU - Oh, Seung Hwan
AU - Choi, Soo Hyung
AU - Yang, Yung Hun
AU - Oh, Min Kyu
N1 - Funding Information:
This research was supported by the National Research Foundation of Korea (NRF) funded by the Ministry of Science and ICT, South Korea ( 2015M3D3A1A01064919 and 2012M1A2A2026560 ).
Publisher Copyright:
© 2021 Elsevier B.V.
PY - 2021/4/30
Y1 - 2021/4/30
N2 - Formate is a promising environmentally friendly and sustainable feedstock synthesized from syngas or carbon dioxide. Methylorubrum extorquens is a type II methylotroph that can use formate as a carbon source. It accumulates polyhydroxyalkanoates (PHAs) inside the cell, mainly producing poly-3-hydroxybutyrate (PHB), a degradable biopolymer. Owing to its high melting point and stiff nature, however, mechanical property improvement is warranted in the form of copolymerization. To produce the PHA copolymer, poly (3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), the endogenous gene phaC was deleted and the pathway genes bktB, phaJ1, and phaC2, with broader substrate specificities, were heterologously expressed. To improve the incorporation of 3-hydroxyvalerate (3HV), the expression level of bktB was improved by untranslated region (UTR) engineering, and the endogenous gene phaA was deleted. The engineered M. extorquens produced PHBV with 8.9% 3HV using formate as the sole carbon source. In addition, when propionate and butyrate were supplemented, PHBVs with 3HV portions of up to 70.6% were produced. This study shows that a PHBV copolymer with a high proportion of 3HV can be synthesized using formate, a C1 carbon source, through metabolic engineering and supplementation with short-chain fatty acids.
AB - Formate is a promising environmentally friendly and sustainable feedstock synthesized from syngas or carbon dioxide. Methylorubrum extorquens is a type II methylotroph that can use formate as a carbon source. It accumulates polyhydroxyalkanoates (PHAs) inside the cell, mainly producing poly-3-hydroxybutyrate (PHB), a degradable biopolymer. Owing to its high melting point and stiff nature, however, mechanical property improvement is warranted in the form of copolymerization. To produce the PHA copolymer, poly (3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), the endogenous gene phaC was deleted and the pathway genes bktB, phaJ1, and phaC2, with broader substrate specificities, were heterologously expressed. To improve the incorporation of 3-hydroxyvalerate (3HV), the expression level of bktB was improved by untranslated region (UTR) engineering, and the endogenous gene phaA was deleted. The engineered M. extorquens produced PHBV with 8.9% 3HV using formate as the sole carbon source. In addition, when propionate and butyrate were supplemented, PHBVs with 3HV portions of up to 70.6% were produced. This study shows that a PHBV copolymer with a high proportion of 3HV can be synthesized using formate, a C1 carbon source, through metabolic engineering and supplementation with short-chain fatty acids.
KW - Formate
KW - Metabolic engineering
KW - Methylorubrum extorquens AM1
KW - PHBV copolymer
KW - SCFAs
UR - http://www.scopus.com/inward/record.url?scp=85101533251&partnerID=8YFLogxK
U2 - 10.1016/j.ijbiomac.2021.02.092
DO - 10.1016/j.ijbiomac.2021.02.092
M3 - Article
C2 - 33610606
AN - SCOPUS:85101533251
SN - 0141-8130
VL - 177
SP - 284
EP - 293
JO - International Journal of Biological Macromolecules
JF - International Journal of Biological Macromolecules
ER -