„Algenetics – Genetic Improvement of Cyanobacteria for theProduction of Biochemicals

  • Alexander Jäger (Speaker)

Activity: Talk or presentationOral presentation

Description

Over the last 60 years, algal biotechnology has shown a range of applications: from the traditional biomass use in human and animal nutrition, technologies for waste-water treatment, products for cosmetics, pharmaceuticals, sources of chemicals, and most recently as a possible feedstock for the ‘second’ or ‘third’ generation of biofuels which do not compete with food crops. Based on pilot experiments, it is claimed that microalgae can produces several times more energy per hectare than land crops, but these yields have yet to be applied commercially. With the higher prices of fossil fuels, there is much interest in algaculture (farming algae) to produce carbon-neutral biofuels, but this technology still has its difficulties mostly due to strain selection, production technology and biomass processing. Prokaryotic cyanobacteria are oxygenic phototrophic microorganisms which were the first on the Earth (about 2.5 billion years ago) to perform photosynthesis – a redox reaction driven by light energy, in which carbon dioxide and water are converted into chemical energy of carbohydrates and oxygen. Substantial benefits of cyanobacteria over plants in bio industrial applications are based on their short life cycles, metabolic plasticity and transformability that offers the possibility of modifying their biochemical pathways and cellular composition by varying culture conditions and/or genetic engineering. Suitable cyanobacterial strains can be grown in aquacultures with inexpensive inputs – namely sunlight, CO2 and water and few required mineral nutrients. Two basic approaches to cultivation technology are used to grow cyanobacteria in mass cultures: one applies to cultivation in open reservoirs, while the other involves closed or semi-closed vessels – photobioreactors with no direct contact between the culture and the atmosphere. In photobioreactors, cyanobacteria could be grown in large-scale for biomass production under controlled conditions in non-arable locations that would not compete with agricultural crops for land or water. Cyanobacteria as the most primitive prokaryotic microorganisms performing oxygenic photosynthesis are suitable subject to genetic manipulation. These microorganisms can be grown in large-scale in photobioreactors in non-arable areas that are inhospitable for agricultural crops. Extensive studies in recent years have resulted in the explosion of available sequenced genomes of cyanobacteria (>40; Gupta et al. 2011), which can be engineered to produce an array of compounds. Some cyanobacterial strains (e.g. Synechocystis, Synechococcus, Anabaena) have been genetically modified to prepare engineered strains. After genetic improvements they might produce biofuels and valuable chemicals. For example bioethanol and starch production from cyanobacteria would not compete with agricultural crops like the first generation biofuel production (food versus fuel discussion). The short life cycle and the easy transformability of cyanobacteria simplify the efforts for genetical improvements.
Period19 Sept 2016
Event titleForschung trift Wirtschahft
Event typeWorkshop
LocationBudweis, Czech RepublicShow on map