Author
SIKKEMA, DIRK - US Department Of Agriculture (USDA) | |
Cal, Andrew | |
Hathwaik, Upul | |
Orts, William | |
Lee, Charles |
Submitted to: PLOS
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 3/29/2023 Publication Date: 7/20/2023 Citation: Sikkema, D., Cal, A.J., Hathwaik, U.I., Orts, W.J., Lee, C.C. 2023. Polyhydroxyalkanoate production in Pseudomonas putida from alkanoic acids. PLOS. 18(7). https://doi.org/10.1371/journal.pone.0284377. DOI: https://doi.org/10.1371/journal.pone.0284377 Interpretive Summary: Society’s reliance on petroleum-based plastic has resulted in a massive accumulation of waste. One solution is to replace conventional plastics, wherever possible, with biodegradable polymers that will break down without toxic byproducts in both controlled waste streams and natural environments. In this study, we have characterized the production of a variety of polyhydroxyalkanoic acids from the bacterial strains of Pseudomonas putida. We have methodically tested the use of a series of alkanoic feedstocks containing 7 to 14 carbons. In addition, we have developed a new defined media recipe that doubles the yield of biopolymer production compared to those used in previous reports. Technical Abstract: Medium-chain-length PHAs from various alkanoic acids (C7 through C14) were made using three strains of Pseudomonas putida, NRRL B-14875, KT2440, and GN112. Growth, cell dry weight yield, PHA yield, monomer distribution and molecular weights were examined. It was found that cell growth and dry weight is about the same for each alkanoic acid if the total carbon is the same and that monomer distribution in the PHA polymer is a function of the alkanoic acid supplied. With heptanoate and octanoate, the PHA produced is primarily 3-hydroxyheptanoate and 3-hydroxyoctanoate. When longer chain fatty acids are supplied, co-polymers are produced that are dominated by 3-hydroxyoctanoate (for even numbered alkanoates) or 3-hydroxynonanoate (for odd numbered alkanoates). It was also determined that the defined media and batch feeding process employed resulted in a significant increase in biomass and PHA production over previous reports. |