CV: Michael Hoppert

General

PD Dr. Hoppert, Michael

Abteilung für Allgemeine Mikrobiologie

Institut für Mikrobiologie und Genetik
Georg-August-Universität Göttingen

Grisebachstr. 8
37077 Göttingen


Phone: +49 (551) 39 - 3782
Fax: +49 (551) 39 - 3808
web site: http://www.uni-goettingen.de/de/111854.html

Email: mhopper@gwdg.de

Born 14. 12. 1963


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Professional career

1983: university-entrance diploma
1989: Diploma in microbiology (major subject), botany and organic chemistry
1993: PhD/Dr. rer. nat., Title: Structure and activity of hydrogen producing systems in water-in-oil microemulsions
June 2005: venia legendi for microbiology

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Positions

Nov. 1993 Appointment as a Akademischer Rat
(Sept. 2006: AkadOR) at the University of Göttingen
(Institute of Microbiology and Genetics,
Dept. Structural Microbiology; since April 2004
Dept. General Microbiology)

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Main fields of research

Research profile

(main research topics in chronological order)
Biological hydrogen production and enzyme activity in reversed micellar systems
Within the framework of a collaborative research program funded by the Federal Ministry of
Research and Technology (BMBF) we developed systems for enhanced biological hydrogen
production. For this purpose, cells of subcellular systems were encapsulated in water-filled
microcompartments and emulsified, with the aid of an appropriate surfactant, in an organic
solvent (reversed micellar solution). We could show that the limited availability of water in the
environment enhanced the catalytic activity, especially of hydrogenases, by a factor of three. The
catalytic activity of the enzymes could be controlled by the amount of water in the system: at a
specific optimized water/surfactant ratio, the activity reached maximum values. It could also be
shown that by microencapsulation of enzymes in reversed micelles the temperature optimum of
the enzyme-catalyzed reaction was raised by 10 - 20 °C (years 1990-1994).
In order to exploit this strategy for other enzyme proteins, in a follow-up of this project, and in
association with the Research Training Group "Chemical activities of microorganisms" (funded
by the German Research Foundation - Deutsche Forschungsgemeinschaft), we tested the
activities of various dehydrogenases in reversed micellar systems and developed strategies for
fine-tuning of enzyme activity by varying the composition of the reversed micellar system
(organic solvent, surfactant, water/surfactant ratio) and achieved enhancement of enzyme
activities by one to two orders of magnitude and temperature optimum shifts by up to 20 °C. We
also developed methods for immobilization of enzymes on lipid bilayer membrane surfaces in
aqueous solutions. Here we could show, that below the phase transition temperature of the used
lipid, specific activity of the membrane-bound enzyme drops down. We could conclude, that
lipid composition and temperature triggers, and possibly regulates activities of membrane
enzymes (years 1994-2002).
This research project was performed in collaboration with the Swiss Federal Institute of
Technology (Group Supramolecular Chemistry) and the Max-Plank-Institute for Biophysical
Chemistry (Group Enzyme Biochemistry).

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Selected publications ( since 2007)

2009
Hames, C., Halbedel, S., Hoppert, M., Frey, J., Stülke, J. (2009) Glycerol metabolism is
important for cytotoxicity of Mycoplasma pneumoniae. J. Bacteriol.191, 747-753.
2008
Jakovljevic, V., Leonardy, S., Hoppert, M., Søgaard-Andersen, L. (2008) PilB and PilT are
ATPases acting antagonistically in type IV pilus function in Myxococcus xanthus. J. Bacteriol.
190, 2411-2421.
Helmstaedt, K., Laubinger, K., Voßkuhl, K., Bayram, Ö., Busch, S., Hoppert, M., Valerius, O.,
Seiler, S., Braus, G.H. (2008) The nuclear migration protein NUDF/LIS1 forms a complex with
NUDC and BNFA at spindle pole bodies. Eukaryot. Cell.7, 1041-1052.
Scharnewski, M., Pongdontri, P., Mora, G., Hoppert, M., Fulda, M. (2008) Mutants of
Saccharomyces cerevisiae deficient in acyl-CoA synthetases secrete fatty acids due to
interrupted fatty acid recycling. FEBS J. 275, 2765-2778.
Wrede, C., Heller, C., Reitner, J., Hoppert, M. (2008) Correlative light/electron microscopy for
the investigation of microbial mats from Black Sea cold seeps. J. Microbiol. Meth, 73, 85-91.
Heller, C., Hoppert, M., Reitner, J. (2008) Immunological localization of coenzyme M reductase
in anaerobic methane-oxidizing archaea. Geomicrobiol. J. 25, 149-156.
2007
Valerius, O., Kleinschmidt, M., Rachfall, N., Schulze, F., Marin, S.L., Hoppert, M., Bömeke, K.,
Fischer, C., Braus, G.H. (2007) The Saccharomyces homolog of mammalian RACK1,
Cpc2/Asc1p, is required for FLO11-dependent adhesive growth and dimorphism. Mol. Cell.
Protemics 11, 1968-1979.
Jendrossek, D., Selchow, O., Hoppert, M. (2007) PHB granules at the early stages of formation
are localised close to the cytoplasmic membrane in Caryophanon latum, Azotobacter vinelandii
and Beijerinckia indica. Appl. Environ. Microbiol. 73, 586-93.
Török, A., Müller, C., Hüpers, A., Hoppert, M., Weiss, T., Siegesmund, S. (2007) Differences in
texture, physical properties and microbiology of weathering crust and host rock: a case study of
the porous limestone of Budapest (Hungary). Geol. Soc. Spec. Publ. 271, 261-276.

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