Disruption of the 2-methylcitric acid cycle and evaluation of poly-3-hydroxybutyrate-co-3-hydroxyvalerate biosynthesis suggest alternate catabolic pathways of propionate in Burkholderia sacchari

Autor(es)

Pereira, Erica Mendes ^{[1, 2]} ; Silva-Queiroz, Sonia Regina ^{[1, 2]} ; Cabrera Gomez, Jose Gregorio ^{[1, 2]} ; Ferreira Silva, Luiziana ^{[1, 2]}

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Inst Ciencias Biomed, Dept Microbiol, BR-05508000 Sao Paulo - Brazil

^[2] Univ Sao Paulo, Programa Posgrad Interunidades Biotecnol, BR-05508900 Sao Paulo - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Canadian Journal of Microbiology; v. 55, n. 6, p. 688-697, JUN 2009.
• Citações Web of Science: 2

Resumo

The objective of the present work was to evaluate the relevance of the 2-methylcitric acid cycle (2MCC) to the catabolism of propionate in Burkholderia sacchari. Two B. sacchari mutants unable to grow on propionate were obtained: one disrupted in acnM, and the other in acnM and prpC deleted. An operative 2MCC significantly reduces the bacterial ability to incorporate 3-hydroxyvalerate (3HV) into a biodegradable copolyester accumulated from carbohydrates plus propionate. The efficiency of the mutants in converting propionate to 3HV units (Y(3HV/prp)) increased from 0.09 g.g(-1) to 0.81-0.96 g.g(-1), indicating that acnM and prpC are both essential for growth on propionate. None of the mutations resulted in achievement of the maximum theoretical Y(3HV/prp) (1.35 g.g(-1)). When increasing concentrations of propionate were supplied, decreasing values of Y(3HV/prp) were observed. The results obtained corroborate the hypothesis of the presence of other propionate catabolic pathways in B. sacchari. The 2MCC would be the more operative pathway, but a second pathway, which remains to be elucidated, would assume more importance under propionate concentrations of 1 g.L(-1) or higher. The efficiency in converting propionate to 3HV units can be improved by decreasing the propionate concentrations, owing to the role of the 2MCC. (AU)

• Processo FAPESP: 03/00745-4 - Avaliação da influência de genes do catabolismo de propionato sobre a síntese de copolímero biodegradável em Burkholderia sacchari e outras bactérias
• Beneficiário: Érica Mendes Pereira
• Modalidade de apoio: Bolsas no Brasil - Doutorado
• Processo FAPESP: 04/14545-0 - Estudo de vias envolvidas no catabolismo de propionato em burkholderia sacchari e sua influencia sobre a producao de copolimero biodegradavel.
• Beneficiário: Luiziana Ferreira da Silva
• Modalidade de apoio: Auxílio à Pesquisa - Regular