title: Improvement of isobutanol production in Saccharomyces cerevisiae by increasing mitochondrial import of pyruvate through mitochondrial pyruvate carrier.
abstract: Subcellular compartmentalization of the biosynthetic enzymes is one of the limiting factors for isobutanol production in Saccharomyces cerevisiae. Previously, it has been shown that mitochondrial compartmentalization of the biosynthetic pathway through re-locating cytosolic Ehrlich pathway enzymes into the mitochondria can increase isobutanol production. In this study, we improved mitochondrial isobutanol production by increasing mitochondrial pool of pyruvate, a key substrate for isobutanol production. Mitochondrial isobutanol biosynthetic pathway was introduced into bat1Δald6Δlpd1Δ strain, where genes involved in competing pathways were deleted, and MPC1, MPC2, and MPC3 genes encoding the subunits of mitochondrial pyruvate carrier (MPC) hetero-oligomeric complex were overexpressed with different combinations. Overexpression of Mpc1 and Mpc3 forming high-affinity MPCOX was more effective in improving isobutanol production than overexpression of Mpc1 and Mpc2 forming low-affinity MPCFERM. The final engineered strain overexpressing MPCOX produced 330.9 mg/L isobutanol from 20 g/L glucose, exhibiting about 22-fold increase in production compared to wild type.
authors.affiliation: School of Chemical and Biological Engineering, Institute of Chemical Processes, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea.
authors.forename: Seong-Hee
authors.initials: SH
authors.lastname: Park
authors.affiliation: School of Chemical and Biological Engineering, Institute of Chemical Processes, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea.
authors.forename: Sujin
authors.initials: S
authors.lastname: Kim
authors.affiliation: School of Chemical and Biological Engineering, Institute of Chemical Processes, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea. hahnjs@snu.ac.kr.
authors.forename: Ji-Sook
authors.initials: JS
authors.lastname: Hahn
mesh_terms: D027321:Anion Transport Proteins / Q000235:genetics / Q000378:metabolism; D001692:Biological Transport / Q000502:physiology; D000440:Butanols / Q000378:metabolism*; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism; D026901:Membrane Transport Proteins / Q000378:metabolism*; D008928:Mitochondria / Q000378:metabolism*; D033681:Mitochondrial Membrane Transport Proteins; D027501:Monocarboxylic Acid Transporters; D017853:Phosphotransferases (Alcohol Group Acceptor) / Q000235:genetics / Q000378:metabolism; D011768:Pyruvate Dehydrogenase Complex / Q000378:metabolism; D019289:Pyruvic Acid / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism
chemical_list: D027321:Anion Transport Proteins; D000440:Butanols; C573715:FMP37 protein, S cerevisiae; C573717:FMP43 protein, S cerevisiae; C573716:MPC2 protein, S cerevisiae; D008565:Membrane Proteins; D026901:Membrane Transport Proteins; D033681:Mitochondrial Membrane Transport Proteins; D027501:Monocarboxylic Acid Transporters; D011768:Pyruvate Dehydrogenase Complex; D029701:Saccharomyces cerevisiae Proteins; C040507:isobutyl alcohol; D019289:Pyruvic Acid; C413542:GPI13 protein, S cerevisiae; D017853:Phosphotransferases (Alcohol Group Acceptor)
keywords: Amino acid metabolism; Biofuel; Isobutanol; Mitochondrial pyruvate carrier; Pyruvate dehydrogenase; Saccharomyces cerevisiae