Kinetic and Morphological Analysis of C. necator Cells During the Synthesis and Degradation of Intracellular Polyhydroxyalkanoates (PHAs)

DAIANA NYGAARD; OXANA YASHCHUK; ANA CAROLINA HEIDENREICH; ÉLIDA B. HERMIDA

Buenos Aires

Congreso; Proceedings of 15th Interamerican Microscopy Congress CIASEM ? SAMIC.; 2020

Argentine Society of Microscopy (SAMIC) and the Committee of the Inter American Society of Microscopy (CIASEM)

The increasing commercialization of PHAs is due to the excellent combination of their properties: thermoplasticity, biodegradability and biocompatibility, which allow the design of products for diverse applications [1], [2]. PHAs are accumulated icroorganisms in the form of intracellular granules under conditions of nutritional stress [3]. The aim of this work is the study by Transmission Electron Microscopy (TEM) the formation, growth and degradation of the PHAs granules during bacteria fermentation.The study was carried out in three stages. In stage 0, the inoculum of C. necator in TYF médium (Tryptone, Yeast, Fructose) was cultivated during 24 h. In stage 1, washed cells were incubated during 72 h in a medium statistically optimized for the PHB production [4]. Finally, in stage 2, cells were incubated for 98 h in a carbon-free medium such that C. necator degrades PHB. Thus, the whole incubation of stages 1 and 2 lasted 170 h.TEM allowed studying the kinetics and morphology of the different stages of accumulation and degradation of the PHAs granules, essential issues for scaling up the production of these biodegradable polyesters.