title: Regulation of 3-hydroxyhexanoate composition in PHBH synthesized by recombinant Cupriavidus necator H16 from plant oil by using butyrate as a co-substrate.
abstract: A (R)-3-hydroxyhexanoate (3HH) composition-regulating technology for poly (3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH) production was developed using recombinant Cupriavidus necator H16 with butyrate as a co-substrate. A new (R)-3-hydroxyhexanoyl-CoA ((R)-3HH-CoA) synthesis pathway was designed and enhanced by replacing the PHA synthase gene (phaC1) of C. necator by the phaCAcNSDG (encoding the N149S and D171G mutant of PHA synthase from Aeromonas caviae) and deactivation of the phaA gene (encoding (β-ketothiolase) from C. necator H16 chromosome). The effect of butyrate as co-substrate was assessed in high-cell-density fed-batch cultures of several C. necator mutants, and the 3HH fraction was successfully increased by adding butyrate to the culture. Moreover, overexpression of BktB (encoding the second β-ketothiolase with broad substrate specificity) enhanced the (R)-3HH-CoA synthesis pathway in the phaA deactivated mutant of C. necator by promoting the condensation of acetyl-CoA and butyryl-CoA into 3-ketohexanoyl-CoA. Consequently, PHBH containing 4.2-13.0 mol% 3HH was produced from butyrate and palm kernel oil by the genetically modified C. necator H16 strains.
authors: GP Business Development Division, Kaneka Corporation, 1-8 Miyamae-machi, Takasago-cho, Takasago, Hyogo 676-8688, Japan. Electronic address: Shunsuke_sato@kn.kaneka.co.jp.
authors: Shunsuke
authors: S
authors: Sato
authors: GP Business Development Division, Kaneka Corporation, 1-8 Miyamae-machi, Takasago-cho, Takasago, Hyogo 676-8688, Japan.
authors: Hiroyuki
authors: H
authors: Maruyama
authors: GP Business Development Division, Kaneka Corporation, 1-8 Miyamae-machi, Takasago-cho, Takasago, Hyogo 676-8688, Japan.
authors: Tetsuya
authors: T
authors: Fujiki
authors: GP Business Development Division, Kaneka Corporation, 1-8 Miyamae-machi, Takasago-cho, Takasago, Hyogo 676-8688, Japan.
authors: Keiji
authors: K
authors: Matsumoto
mesh_terms: D020155:3-Hydroxybutyric Acid / Q000096:biosynthesis* / Q000737:chemistry*; D000105:Acetyl Coenzyme A / Q000378:metabolism; D000102:Acetyl-CoA C-Acyltransferase / Q000378:metabolism; D000214:Acyl Coenzyme A / Q000378:metabolism; D000217:Acyltransferases / Q000235:genetics / Q000378:metabolism; D057585:Aeromonas caviae / Q000201:enzymology; D061249:Batch Cell Culture Techniques; D002087:Butyrates / Q000378:metabolism* / Q000494:pharmacology; D002208:Caproates / Q000737:chemistry* / Q000378:metabolism*; D020118:Cupriavidus necator / Q000235:genetics / Q000378:metabolism*; D010938:Plant Oils / Q000378:metabolism*; D013379:Substrate Specificity; D000094122:Polyhydroxybutyrates
chemical_list: D020155:3-Hydroxybutyric Acid; D000105:Acetyl Coenzyme A; D000102:Acetyl-CoA C-Acyltransferase; D000214:Acyl Coenzyme A; D000217:Acyltransferases; D002087:Butyrates; D002208:Caproates; D010938:Plant Oils; C115940:poly(3-hydroxybutyrate-co-3-hydroxyhexanoate); D000094122:Polyhydroxybutyrates; C045051:3-hydroxyhexanoic acid; C049446:3-ketohexanoyl-coenzyme A; C024343:butyryl-coenzyme A; C077225:poly(3-hydroxyalkanoic acid) synthase
keywords: 3-Ketohexanoyl-CoA; Butyrate; Palm oil; Polyhydroxyalkanoate; Ralstonia eutropha; β-Ketothiolase