Autor(es)

Santos-Oliveira, Pedro Henrique ; Silva, Jefferson Gonsalves Pinheiro ; Blank, Lars Mathias ; Silva, Luiziana Ferreira ; Gomez, Jose Gregorio Cabrera

• Tipo de documento: Artigo Científico
• Fonte: International Journal of Biological Macromolecules; v. 256, p. 9-pg., 2023-12-05.

Resumo

Pseudomonas sp. LFM693 is a 2-methylisocitrate lyase (prpB) disrupted mutant. This enzyme catalyzes a step in the 2-methylcitrate cycle, the only known and described pathway for propionate oxidation in this organism. The affected mutants can efficiently produce PHA containing even and odd-chain length hydroxyalkanoates (HA(even/odd)) in the presence of propionate and glucose. In this study, a constant fed-batch configuration was utilized to control the composition of PHA and decrease the toxicity of propionate. The incorporation of HA(odd) into the copolymer was linear, ranging from 7 to approximately 30 %, and correlated directly with the propionate/glucose molar ratio in the feeding solution. This allowed for the molecular composition of the mclPHA to be fine-tuned with minimum process monitoring and control. The average PHA content was 52 % cell dry weight with a molar composition that favored 3-hydroxyalkanoates containing C8, C9, and C10. The conversion factor of propionate to HA(odd) varied between 0.36 and 0.53 mol center dot mol(-1) (Y-HAodd/prop.), which are significantly lower than the theoretical maximum efficiency (1.0 mol center dot mol(-1)). These results along with the lack of 2-methylisocitrate as a byproduct provides further support for the evidence that the mutant prpB(-) is still capable of oxidizing propionate. (AU)

• Processo FAPESP: 03/01602-2 - Avaliacao do metabolismo de sintese de phamcl e controle de sua composicao monomerica.
• Beneficiário: José Gregório Cabrera Gomez
• Modalidade de apoio: Auxílio à Pesquisa - Jovens Pesquisadores
• Processo FAPESP: 13/50357-2 - Programmable balancing of growth and formation of polyhydroxyalkanoates in escherichia coli. (fapesp-nwo)
• Beneficiário: José Gregório Cabrera Gomez
• Modalidade de apoio: Auxílio à Pesquisa - Regular