Department of Applied & General Microbiology


 PD. Dr. Ruth Schmitz


Diploma, (Microbiology) University of Marburg, Germany

1992 Ph.D., (Microbiology) University of Marburg, Germany
1994 -1996

Postdoc, University of California, Berkeley, California, USA

7/2001 Habilitation

 Academic Positions

1996-today University of Göttingen, Department of Microbiology & Genetics





 Mailing address:
 Institut für Mikrobiologie & Genetik
 der Universität Göttingen,

 D-37077 Göttingen, Germany
 Tel. (++49)-551-39-3796 /-3813
 Fax. (++49)-551-393793






Regulation of nitrogen fixation in Klebsiella pneumoniae.
Under oxygen- and nitrogen-limiting growth conditions K. pneumoniae is able to reduce molecular nitrogen to ammonia. Synthesis of the key enzyme nitrogenase is regulated in response to molecular oxygen and combined nitrogen by the two regulatory proteins NifA and NifL. Our research is focused on the characterization of the oxygen and nitrogen signal transduction towards NifL and NifA by genetic, biochemical and molecular biological methods.

Molecular and biochemical characterization of the nitrogen regulatory network in the methanogenic Archaeon Methanosarcina mazei Gö1
We are currently focusing on the characterization of nitrogen fixation in M. mazei and its regulation. Our goal is to analyze the regulatory network of nitrogen metabolism in M. mazei using classical genetic approaches and modern molecular tools arising from the knowledge of the complete genome sequence.

Construction of environmental libraries and screening for acquired abilities of the resulting recombinant organisms.
It has been estimated that > 99 % of microorganisms observable in nature typically can not be cultivated by using standard techniques. Thus, a large fraction of the diversity in an environment is still unknown. Our approach is to use the genetic diversity of the micro-organisms in a certain environment as a whole to encounter new genes and gene products for various purposes. The genetic diversity is accessed by isolation of DNA followed by direct cloning of functional genes from environmental sample


Selected Publications

Grabbe R, Schmitz RA. (2003) Oxygen control of nif gene expression in Klebsiella pneumoniae depends on NifL reduction at the cytoplasmic membrane by electrons derived from the reduced quinone pool. Eur J Biochem. 270(7):1555-66.
Ehlers C, Grabbe R, Schmitz RA (2002). Characterization of GlnK1 from Methanosarcina mazei strain Gö1: Complementation of an Escherichia coli glnK mutant strain by M. mazei     GlnK1.  J. Bacteriol. 184: 1028 -1040.
Deppenmeier U, …Schmitz RA, …Gunsalus RP, Fritz HJ, Gottschalk G. (2002) The genome of Methanosarcina mazei: evidence for lateral gene transfer between bacteria and archaea. J Mol Microbiol Biotechnol 4(4):453-61
Klopprogge K, Grabbe R, Hoppert M, Schmitz RA (2002). Membrane association of Klebsiella pneumoniae NifL is affected by molecular oxygen and combined nitrogen. Archives of Microbiology, 117, 223-234.
Klopprogge K, Stips J, Schmitz RA (2002). The inhibitory form of NifL from Klebsiella  pneumoniae exhibits ATPase activity only when synthesized under nitrogen sufficiency. Biochem. Biophys. Acta 1594, 243-54.
Schmitz RA, Klopprogge K, Grabbe R (2002).
Regulation of nitrogen fixation in Klebsiella pneumoniae and Azotobacter vinelandii: NifL, transducing two environmental signals to the nif transcriptional activator NifA  (Minireview). J. Mol. Microbiol. Biotechnol. 4, 235-242.
Henne A, Schmitz RA, Bömeke M, Gottschalk G, Daniel R  (2000) Screening of environmental DNA libraries for the presence of genes conferring lipolytic activity on Escherichia coli. Appl. Environ. Microbiol. 66, 3113-3116.
Henne A, Daniel R, Schmitz RA, Gottschalk, G (1999) Construction of environmental DNA libraries in Escherichia coli and screening for the presence of genes conferring utilization of 4-hydroxybutyrate. Appl. Environ. Microbiol. 65, 3901-3907.


Articles in German
Daniel R., Schmitz R.A. und W. Streit (2002) aus Wattenmeer und Wüstensand. Georgia Augusta. 1: 111-115