Characterization of cyanobacteria as polyhydroxybutyrate producer

abstract

English

Cyanobacteria are Gram-negative prokaryotes belong to a group of photosynthetic bacteria. In comparison with heterotrophic microorganisms, cyanobacteria utilize atmospheric nitrogen and CO2 without any additional substrates. This ability of these microorganisms could be employed in biotechnology for production of bioplastics-polyhydroxyalkanoates (PHAs) which are primary accumulated as a storage material in cells in form of intracellular granules. In this study, there were optimized and used several instruments including microscopic techniques such as Cryo-scanning electron microscopy and transmission electron microscopy and fluorescence lifetime imaging microscopy using Nile red as fluorescent probe. Due to these instrumental techniques, morphology of intracellular space and surface of cells were characterized. Next group of methods which were employed were spectroscopic techniques such as UV-Vis spectroscopy measured in two modes (turbidimetry and integrating sphere) and Fourier transform infrared spectroscopy. All these diverse techniques were used for detection and characterization of pigments (chlorophylls, carotenoids etc.) and PHAs, in our case poly(3-hydroxybutyrate) (P3HB). To verify results, gas chromatography was employed, for determination of amount of P3HB in biomass. Cyanobacteria was also characterized by flow cytometer which count cells and at the same time distinguish cells including P3HB and without due to fluorescent probe BODIPY and live/dead fluorescent probe SYTO Blue.

Cyanobacteria, fluorescent probe, microscopic techniques, poly(3hydroxybutyrate), spectroscopy, chromatography

SLANINOVÁ, E.; ČERNAYOVÁ, D.; ŠEDRLOVÁ, Z.; MRÁZOVÁ, K.; SEDLÁČEK, P.; NEBESÁŘOVÁ, J.; OBRUČA, S.

1. 12. 2021

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