Author
SIKKEMA, DIRK - US Department Of Agriculture (USDA) | |
Cal, Andrew | |
Hathwaik, Upul | |
Kibblewhite, Rena | |
Orts, William | |
Lee, Charles |
Submitted to: Meeting Abstract
Publication Type: Abstract Only Publication Acceptance Date: 2/28/2019 Publication Date: 6/22/2019 Citation: Sikkema, D.W., Cal, A.J., Hathwaik, U.I., Kibblewhite, R.E., Orts, W.J., Lee, C.C. 2019. Polyhydroxyalkanoate production in Pseudomonas putida from alkanoic acids. Meeting Abstract. [abstract]. ASM Microbe 2019 conference, San Francisco, CA. June 20-24, 2019. Interpretive Summary: Technical Abstract: The widespread deployment of renewable, biodegradable polymers, such as polyhydroxyalkanoates (PHA), to displace petroleum-based plastics would be a boon to society and the environment. To that end, multiple studies have been conducted to produce microbial PHA from Pseudomonas sp. fed with various alkanoic acids. Because this previous data was collected using methodologies that varied in critical aspects, such as culture media and size range of alkanoic acids, it has been difficult to compare the results for a thorough understanding of the relationship between feedstock and PHA production. Therefore, this study utilized consistent culture media with a wide range of alkanoic acids (C7-C14) to produce medium chain length PHAs. Three strains of Pseudomonas putida (NRRL B-14875, KT2440, and GN112) were used, and growth, cell dry weight, PHA yield, monomer distribution, and molecular weights were all examined. It was found that cell growth and dry weight were about the same for each alkanoic acid if the total supplied carbon was the same and that monomer distribution in the PHA polymer was a function of the alkanoic acid supplied. With heptanoate and octanoate, the PHA produced was primarily 3-hydroxyheptanoate and 3-hydroxyoctanoate, respectively. When longer chain fatty acids were supplied, copolymers were produced that were dominated by 3-hydroxyoctanoate and 3-hydroxynonanoate for even- and odd-numbered alkanoates, respectively. In addition, a defined media formulation and batch feeding process were employed and resulted in a significant increase in biomass and PHA production over previous reports. |