Laboratory for Molecular Microbiology
Prof. Dr. Erhard Bremer bremer@biologie.uni-marburg.de
patricia.wagner@biologie.uni-marburg.de
Picture provided by:
(20. 02. 1954)
Diplom (Biology), University of Tübingen (1980)
Dr. rer. nat. (Biology), University of Tübingen (1982)
Postdoctoral fellow, National Cancer Institute (NCI), Frederick,
Maryland, U.S.A. (1982-1984)
Staff scientist (C1), Department of Microbiology, University of
Konstanz (1984-1990)
Habilitation (Microbiology and Genetics), University of Konstanz
(1989)
Assistant Professor (C2; Microbiology), University of Konstanz
(1990-1992)
Offer for an associated professorship (C3) for Applied Microbiology
at the University of Saarbrücken (1992; declined)
Head (C3) of the group "Osmoregulation" at the Max Planck Institute
for terrestrial Microbiology, Marburg (1992-1995)
Adjunct Professor (Microbiology) at the Dept. of Biology,
University of Marburg (1993-1995)
Full professor of Microbiology and Head of the Laboratory for
Molecular Microbiology at the Dept. of Biology, University of Marburg
(1995-current)
Speaker of the Collaborative Research Center for "Soil
Microbiology" (SFB 395) (2000-2007)
Offer for a full professorship (C4) for Microbiology at the
Ludwig-Maximilians-University, Munich (2002; declined)
Vice-Dean of the Department of Biology, University of Marburg
(10/2009 - 03/2011)
Elected as member of the "European Academy of Microbiology" (EAM)
(2011)
Vice-Speaker of the Collaborative Research Center for "Microbial
Diversity in Environmental Signal Response" (SFB 987) (2012 -
current)
24. April 2013, Philipps-Universität Marburg, Alte
Aula. Flyer Poster.
C o n g r a t u l a t i o n s to K a t h
l e e n ! November 30, 2012
Prof. Dr. E. Bremer (Doktorvater) und Prof. Dr. D. Jahn (neuer Präsident der VAAM) freuen sich mit PD Dr. J. Boch
VAAM hier.
A key event in the evolution of
primordial cells on earth was the development of the cytoplasmic
membrane since it created a protected reaction chamber for the
performance of life’s vital attributes (faithful copying of the genetic
material and cell division, development of an ordered metabolism,
generation of energy producing systems to fuel import and export
transport processes). However, the invention of the semi-permeable
cytoplasmic membrane and the subsequent development of a protective
cell wall (e.g., the peptidoglycan sacculus) also created a severe
problem for the microbial cells because this protected environment with
its high concentrations of nucleic acids, proteins, organic metabolites
and inorganic ions possesses a very substantial osmotic potential.
This, in turn, creates an osmotic driving force that triggers water
influx into the cell and thereby generates an intracellular hydrostatic
pressure, the turgor, whose magnitude can in certain groups of
microorganisms (e.g. Bacilli and Staphylococci) vastly exceed that
present in a car tire. Turgor is considered essential for cell
expansion and viability, but its magnitude is affected by fluctuations
in the osmotic conditions of the varied habitats of microorganism.
Fig. 1. From a proto-cell to
modern-day microbial cells: water-management and control of turgor is
critical for cellular survival.
Bacillus
subtilis (picture kindly provided by Laura Czech and Dr.
Karl-Heinz Rexer, Philipps Universität Marburg)
We are studying the genetic regulatory
circuits that permit microbial cells to detect osmotic changes in their
environment and study the cellular response systems that allow cells
challenged by high salinity to cope with osmotic stress. We use the
Gram-positive soil bacterium B acillus subtilis and
various taxonomically closely related Bacillus species as our primary
model system. Important compatible solutes for Bacilli are the amino
acid L-proline, the trimethylammonium compound glycine betaine and the
tetrahydropyrimidine ectoine and its derivative hydroxyectoine. These
compounds can either be synthesized in response to osmotic stress or
can be taken up from the environment through osmotically controlled
high-affinity uptake systems. Exposure of B. subtilis to high
salinity (equivalent to dried-out soil) triggers rapid water efflux
that is counteracted by the cell through increased uptake of potassium
ions and the subsequent synthesis and import of compatible solutes
(e.g., L-proline and glycine betaine). Compatible solute accumulation
allows potassium efflux through dedicated extrusion systems and thereby
permits the cell to reduce the ion strength of the cytoplasm without
compromising its osmotic potential and ability to maintain
physiological adequate levels of turgor. An important aspect of our
work on the use of compatible solutes by B. subtilis as
osmo-stress and temperature stress protectants is the analysis of
osmotically controlled transport systems for the import of this class
of compounds.We study the genetic regulation of the structural genes
for these import systems in response to increased salinity
(“osmoregulation”) and characterize structurally and biochemically
components - primarily the extracellular ligand binding proteins - of
ABC-transporters for various types of compatible solutes.
Fig. 3.
Central osmo-stress response systems for the water-management
by the soil Bacillus subtilis facing a high salinity
environment .
The soil bacterium Bacillus
subtilis synthesizes the compatible solute glycine betaine through
the oxidation of the precursor molecule choline. It imports for this
purpose choline with high affinity through the osmotically inducible
ABC transporter OpuB. Left : A view from the crystallization
screen with the purified OpuBC protein (picture kindly provided by Dr.
Sander H.J. Smith; University of Düsseldorf, Germany). Right :
Overall crystal structure of the OpuBC protein in complex with its
ligand choline (PDB code: 3R6U). The OpuBC crystal structure and the
molecular determinants of the choline-binding site were report by
Pittelkow et al . (J. Mol. Biol. 411:53-67, 2011).
Fig. 4. Structura l analysis
of the choline-binding protein OpuBC required for the functioning of
the choline-specific OpuB ABC-transporter from Bacillus
subtilis .
(SYMIKRO)
Weitere Nachrichten haben wir hier
im Archiv eingestellt.
Ziegler C, Bremer E, Krämer R. The BCCT family of carriers:Mol Microbiol.
78 : 13-34 (2010)
Hoffmann, T., von Blohn, C., Stanek, A., Moses, S., Barzantny, H. and Bremer, E. Bacillus subtilis cells.Appl. Environ.
Microbiol. 78: 5753-5762 (2012) aem.asm.org
Fischer, K. E. & Bremer, E. yqiHIK PromotorBacillus subtilis is Controlled at a DistanceJ. Bacteriol. 194:
5197-5208 (2012) jb.asm.org
Hoffmann, T. and Bremer, E.
(2011). Bacillus
subtilis via compatible solute acquisition. J. Bacteriol.
193:1552-1562.Bremer, E. (2011) . A look into the aromatic cage.
Crystal Ball-2011. Env. Microbiol. Rep.3:1-5.Müller, S., Hoffmann, T., Santos, H., Saum, S.
H., Bremer, E. and Müller V. (2011). abl -like genes: Production of the archaeal osmolyte
Nε - acetyl-β-lysine by homologous overexpression of the
yodP-kamA genes in Bacillus subtilis. Appl.
Microbiol. Biotechnol. 91:689-697.Pittelkow, M. and Bremer (2011) . Cellular
adjustments of Bacillus subtilis and other Bacilli to
fluctuating salinities. In: Halophiles and Hypersaline Environments:
Current Research and Future Trends. (Eds. A. Ventosa, A. Ohren and Y.
Ma). (Springer, Berlin; 1st Edition.) S. 275-302. Tschapek,
B., Pittelkow, M., Sohn-Bösser, L., Holtmann, G., Smits, S. H. J.,
Gohlke, H., Bremer, E. and Schmitt, L. (2011) Af ProX into its high affinity, closed state. J. Mol.
Biol. 411: 36-52. Pittelkow,
M., Tschapek, B., Smits, S. H. J., Schmitt, L. and Bremer, E.
(2011) .Bacillus subtilis in complex with choline.
J. Mol. Biol. 411:53-67. Eppinger,
M., ... ... ..., Bremer, E., Jahn, D., Ravel, J. and Vary, P. S.
(2011) Bacillus megaterium strains QM B1551 and DSM319. J.
Bacteriol. 193: 4199-4213. Stöveken,
N., Pittelkow, M., Sinner, T., Jensen, R. A., Heider, J. and Bremer, E.
(2011) Pseudomonas stutzeri A1501. J. Bact. 193:445-4468.Kuhlmann, A.
U., Hoffmann, T., Bursy, J., Jebbar, M. and Bremer, E.
(2011) Virgibacillus pantothenticus. J. Bacteriol. 193:
4699-4708.
Moses, S.,
Sinner, T., Zaprasis, A., Stöveken, N., Hoffmann, T., Belitsky, B. R.,
Sonenshein, A. L. and Bremer, E. Bacillus subtilis : uptake and catabolism. J.
Bacteriol. 194: 745-758.Nau-Wagner,
G., Opper, D., Rolbetzki, A., Boch, J., Kempf, B., Hoffmann, T. and
Bremer, E. (2012)Bacillus subtilis through the
choline-sensing and glycine betaine-responsive GbsR repressor. J.
Bacteriol. 194: 2703-2714.Hoffmann,
T., von Blohn, C., Stanek, A., Moses, S., Barzantny, H. and Bremer,
E. (2012)Bacillus
subtilis cells. Appl. Environ. Microbiol. 78: 5753-5762.Fischer, K.
E. and Bremer, E. yqiHIK promotor from Bacillus subtilis is
controlled at a distance. J. Bacteriol. 194: 5197-5280.
Zaprasis,
A., Brill, J., Thüring, M., Wünsche, G., Heun, M., Barzantny, H.,
Hoffmann, T. and Bremer, E. Bacillus subtilis through import and proteolysis of
proline-containing peptides. Appl. Environ. Microbiol. 79:
576-587.Hoffmann,
T., Wensing, A., Brosius, M., Steil. L., Völker, U. and Bremer,
E. opuA expression in
Bacillus subtilis and its modulation in response to
intracellular glycine betaine and proline pools. J. Bacteriol. 195:
510-522.
Die AG Bremer erschließt eine neue Leserschaft für wichtige Publikationen.
Neues dynamisches Mitglied der AG Bremer.
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Zuletzt aktualisiert:
15.03.2013
·
Patricia Wagner
