DI-UMONS : Dépôt institutionnel de l’université de Mons

Recherche transversale
(titres de publication, de périodique et noms de colloque inclus)
2017-05-22 - Colloque/Présentation - poster - Anglais - 1 page(s)

Bayon-Vicente Guillaume , Leroy Baptiste , Gerbaux Pascal , Wattiez Ruddy , "Quantification of polyhydroxyalkanoates in the non-sulphur purple bacterium Rhodospirillum rubrum S1H" in 3rd edition of international conferences : green chemistry and white biotech - industry of the future, Mons, Belgique, 2017

  • Codes CREF : Biochimie (DI3112), Bactériologie générale (DI3131)
  • Unités de recherche UMONS : Protéomie et Microbiologie (S828)
  • Instituts UMONS : Institut des Biosciences (Biosciences)
Texte intégral :

Abstract(s) :

(Anglais) Rhodospirillum rubrum is a purple non-sulfur bacterium. This group of bacteria is well-known for its huge metabolic versatility. Preliminary studies conducted at the laboratory of Proteomic and Microbiology pointed out the link between cultivation conditions and the production of polyhydroxyalkanoates (PHA) in the organism here above mentioned. Effectively, the photoheterotrophic cultivation of this bacterium with acetate or butyrate was accompanied by a tremendous increase of the intracellular PHA content (i.e. PHA granules). Those intracellular bodies are usually accumulated whenever another nutrient than carbon is limiting (e.g. N, P, S, …) and serve as carbon and energy supply. On the contrary, PHA production observed in Rs. spirillum is not associated to a nutrient deficiency. Our hypothesis is that the cultivation of Rs. spirillum in presence of a reduced carbon source (e.g. butyrate or acetate) induces a redox stress inside the cell. The assimilation of PHA could therefore represents a way to equilibrate the intracellular redox balance. The comprehension of the PHA accumulation by Rs. rubrum require the establishment of specific protocol for the PHA extraction. Thanks to methanolysis, we have successfully extracted and identify PHA, via GC-TOF, monomers issued from bacteria cultivated in presence of 62 mM acetate. As expected, the presence of acetate induced the unique production of polyhydroxybutyrate. The culture in presence of other volatile fatty acids (e.g. the valerate) or a mix of those compounds could represent a way to obtain different type of polyhydroxyalkanoates with various mechanical or thermal properties. This pioneering project will allow us to optimise the use of volatile fatty acids derived from the wastewater treatments for the production of high added value biopolymers, namely the PHA.