Production of a copolyester of 3-hydroxybutyric acid and 3-hydroxyvaleric acid from single unrelated carbon sources by a mutant ofAlcaligenes eutrophus

✍ Scribed by Alexander Steinbüchel; Ursula Pieper

• Publisher: Springer
• Year: 1992
• Tongue: English
• Weight: 562 KB
• Volume: 37
• Category: Article
• ISSN: 1432-0614
• DOI: 10.1007/bf00174193

✦ Synopsis

Alcaligenes eutrophus mutant strain R3, which is a spontaneous revertant to prototrophy of an isoleucine-auxotrophic mutant of the wild-type strain H16, accumulated a copolyester consisting of 3-hydroxybutyric acid (3HB) as main constituent and of 3hydroxyvaleric acid (3HV), i.e. poly(3HB-co-3HV), as the only other constituent from various single unrelated substrates, which were provided in excess, after a nutrient essential for growth was depleted in the medium. Poly(3HB-co-3HV) was produced from fructose, gluconate, succinate, acetate or lactate during cell starvation of the nitrogen, sulphur or magnesium source. Although 3HV amounted to only 8 mol% of the constituents of the polyester, this study provides a general rationale for construction and utilization of mutants of poly(3HB)-accumulating bacteria that are altered in the metabolism of branched-chain amino acids for the production of poly(3HB-co-3HV) from single unrelated substrates.