Polyhydroxyalkanoate production in Pseudomonas putida from alkanoic acids of varying lengths

Abstract

Many studies have been conducted to produce microbial polyhydroxyalkanoates (PHA), a biopolymer, 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 titer, monomer distribution, and molecular weights were all examined. It was determined that although all the strains produced similar PHA titers using C7-C9 alkanoic acids, significant differences were observed with the use of longer chain feedstocks. Specifically, KT2440 and its derivative GN112 produced higher PHA titers compared to B-14875 when fed longer chain alkanoates. We also compared several analytical techniques for determining amounts of PHA and found they produced different results. In addition, the use of an internal standard had a higher risk of calculating inaccurate concentrations compared to an external standard. These observations highlight the importance of considering this aspect of analysis when evaluating different studies.

Acid hydrolysis of Solanum tuberosum periderm for accumulation of polyhydroxyalkanoates in Pseudomonas putida MTCC 2475

“…In a study by Sikkema et al (2023) , three distinct strains of Pseudomonas putida , namely, NRRL B-14875, KT2440, and GN112, were employed as microbial cultures for the assimilation of fatty acids as the carbon source. The growth medium consisted of 20 mM ammonium sulfate, 50 mM potassium phosphate, 140 µM calcium carbonate, 2 µM copper sulfate, and 0.1 mL of a trace element solution.…”

“…Sharma et al (2012) reported 22.6% mcl PHA of CDW from an isolated strain of Pseudomonas putida LS46 which is closely related to KT2440 (a potent PHAproducing recombinant strain) by using synthetic glucose (2%) as a carbon source. In a study by Sikkema et al (2023), three distinct strains of Pseudomonas putida, namely, NRRL B-14875, KT2440, and GN112, were employed as microbial cultures for the assimilation of fatty acids as the carbon source. The growth medium consisted of 20 mM ammonium sulfate, 50 mM potassium phosphate, 140 µM calcium carbonate, 2 µM copper sulfate, and 0.1 mL of a trace element solution.…”

Tailoring Pseudomonas putida feedstocks for enhanced medium-chain-length polyhydroxyalkanoate production and biomedical nanoemulsion applications

“…Numerous studies have investigated the use of glucose as a sole carbon and energy source for Pseudomonas putida KT2440 in the production of mcl-PHA, ,− achieving a maximum yield of 0.6 g PHA per liter in shake flask experiments. Additionally, research has been conducted on using decanoic acid (F10) and dodecanoic acid (F12), with Sikkema et al and Wang and Nomura finding that the maximum PHA yields in shake flask experiments for F10 and F12 reached 1.8 and 2.0 g PHA per liter, respectively. However, to the best of our knowledge, no studies have been conducted on the cofeeding of glucose with fatty acids (F10 and F12) to Pseudomonas putida KT2440 to improve the yield over fatty acids alone, while the cofeeding of decanoic acid and glucose in recombinant Escherichia coli, and cofeeding of dodecanoic acid and glucose to engineered Pseudomonas entomophila, Aeromonas hydrophila CGMCC 0911, and Aeromonas hydrophila 4AK4 has been reported.…”