Environmental Biotechnology R&D
Kornél L. Kovács, Department of Biotechnology,
University of Szeged and Biological Research Center, Szeged
Environmental biotechnology plays an increasingly important role in the accession stage of the new EU member countries. Therefore the European Federation of Biotechnology has established one of its Regio-nal Branch Offices at the University of Sze-ged, where renewable energy production and bioremediation are in the focus of R&D.
Among the alternative energy carriers, hydrogen is preferred. Hydrogen can be produced in biological processes: solar energy captured by the photosynthetic apparatus is converted into chemical energy, oxygen and hydrogen can be produced. Upon utilization, these are combined to form water and energy is released in a cycle driven by the practically unlimited and safe energy of the sun. In addition to offering an alternative for the global energy crisis, biologically produced hydrogen may also serve as reductant for numerous microbiological activities of environmental significance. This principle has been employed in the complex microbiological series of events that leads to biogas formation. Biogas formation is intensified through the microbiological manipulation of the intermediate hydrogen production steps according to our patented procedure. The method has been tested in field experiments using agricultural and municipal organic wastes.
The understanding of molecular fundamentals of biohydrogen production and utilization among microbes is a goal of supreme importance both for basic and applied research applications. The key enzyme in biological hydrogen metabolism is hydrogenase, which catalyses the formation or decomposition of hydrogen. The simple-looking task is solved by a sophisticated molecular mechanism. Most hydrogenases are metalloenzymes, harbouring Ni and Fe atoms. Like most metalloenzymes, hydro-genases are extremely sensitive to inactivation by oxygen, high temperature, CO, CN, and other environmental factors. These properties are not favourable for the potential biotechnological applications.
A purple photosynthetic bacterium (Thiocapsa roseopersicina) contains hydro-genases, which display outstanding stability among enzymes possessing the same catalytic function. Understanding, through molecular biological studies, the physiological properties and the molecular factors that stabilize hydrogenases is expected to help design various enzymes equipped with resistance to the inactivating effect of high temperature, oxygen, and/or proteolytic attack for future biotechnological use. A genomic approach has been launched in order to understand the complex problem.
Hyperthermophiles and Methanotrophs
Hyperthermophilic micro-organisms grow above 80°C, and cannot proliferate below 70°C. By definition, enzymes operating in these unusual creatures are heat stable, therefore they offer an obvious advantage for biotechnological applications. In their chemolithotrophic mode of growth hydrogen metabolism plays a crucial role. We have developed a novel technique to plate hyper-thermophilic archaea. This is the first major step to study their microbiology, molecular biology and genetics.
Methanotrophic bacteria typically contain another metalloenzyme, methane mono-oxygenase (MMO). MMO can also attack several compounds representing serious environmental and public health hazard, such as chlorinated hydrocarbons. Methanotrophs are significant for practical utilization to produce alternative energy sources and environmental protection and remediation, improving the general quality of life.
Biodegradation of Xenobiotics
An important foreseeable task is the degradation of industrial and natural hazardous chemicals by the use of naturally occurring microbiological isolates. Because microorganisms can destroy the non-naturally occurring contaminants only slowly and hardly, it is a challenge to identify species that are able to survive and grow in this very unfavourable environment. Several microbiological degradation systems have been developed to efficiently bioremediate halogenated chemicals, sulfonated aromatic chemicals, keratin-containing waste of the food industry. Keratin is converted in a patented process efficiently to biohydrogen. A new fermentation facility is operated by the spin-off company Alfa-Bioner Ltd. to cultivate microbes for large scale bioremediation applications.
Prof. Dr. Kornél Kovács
Dep. of Biotechnology, University of Szeged
Tel./Fax: +36-62-544-351 / -352