Gábor RÁKHELY
senior research associate

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András TÓTH research associate
Ágnes DUZS Ph.D. student
Botond HEGEDŰS Ph.D. student
Ágnes ERDEINÉ KIS Ph.D. student

GASEOUS BIOFUELS

Alternative biofuels might be produced from renewable energy sources, such as Sun energy. The light can be utilized directly for photobiohydrogen evolution or can be converted into biomass, e.g. energy plants, biowastes. The organic wastes might be used for evolution of either hydrogen or biogas via dark anaerobic fermentation.


Biohydrogen

Hydrogen is considered as the cleanest and one of the most promising energy carriers of the future. Hydrogen can be produced by various approaches including biological tools. Hydrogenases and nitrogenases are the enzymes capable to produce hydrogen. Hydrogenases are the dedicated enzymes for reduction of protons or hydrogen oxidation. According to the metal content of the catalytic subunit, there are NiFe, FeFe and Fe only hydrogenases. Nitrogenases could also be classified according to their metal content.

NiFe hydrogenases and nitrogenases are in the central focus of our research. Our aims are to understand the molecular events and metabolic contexts of hydrogen metabolism. The enzymes of photosynthetic and fermentative bacteria are good models for studying the individual metabolic linkages of the various hydrogenases as well as for disclosing the structure-function relationships of the enzymes.



Proton transport pathway in the NiFe hydrogenase of T. roseopersicina


The dark and photofermentation can be sequentially combined. A dual system was developed in a EU FP6 program for combination of the photo- and dark fermentation technology to evolve hydrogen (link) . The metabolic background of the processes was studied by tools of genetics, molecular biology, functional genomics and biophysics in the frame of SOLARH2 EU FP6 programme (link). The fundamentals of a novel biohydrogen producing technology were established which should be further developed for commercial applications.


Biogas

Biogas production is a complex anaerobic digestion process involving the concerted action of numerous microbes. Organic wastes, biomass, energy plants can also be utilized for production of biogas. The biomethane formation is a result of numerous consecutive biochemical reactions having many branching points, competitive routes.

The aims of our resaerch are to understand the whole chain of the fermentation process and to utilize this information for intensification of biogas production. Chemical, microbial and metagenomic techniques are used for monitoring the chemical and microbial changes during the processes. This knowledge might be utilized for designing novel biotechnological approaches for economic biofuel production.



BIOREMEDIATION

Green biofuels can be generated from hazardous wastes, as well. We could successfully combined the bioremediation processes with gaseous fuel output. Two-stage fermentation process was developed for utilization of keratin-containing wastes to produce biohydrogen. This research was expanded with studying the bioremediation of oils, unctuous wastes, (substituted) aliphatic and aromatic hydrocarbons. Several biological tools were developed for for neutralization of these hazardous wastes. The biochemical events of the conversion of various pollutants are mapped by conventional and high-throughput approaches.



PHAGE THERAPY

Pathogen microbes might be considered as hazardous biopollutants. Phage therapy studies were recently initiated in our lab for bioremediation of pathogen microbes using their natural enemies, bacteriophages. Bacteriophages are very potent alternatives of antibiotics since they might have pharmaceutical, food safety, environmental and commercial applications. Phages against human, animal and plant pathogeni microbes are isolated and characterized by genomic and microbiological methods and their applications as selective and efficient biocontrol agent are developed.