Dr. rer. nat. Tom Großmann

The chemist developed a signal amplifying method for molecular gene diagnostics at the Humboldt University of Berlin

He was born in 1978 in Merseburg and studied Chemistry from October 1999 until September 2003 at the Humboldt University of Berlin. He moved to the University of California, Berkeley where he performed studies towards the diploma degree under the supervision of Prof. Dr. K. P. C. Vollhardt and Prof. Dr. G. Szeimies.

Tom Großmann joined the group of Prof. Dr. O. Seitz at Humboldt University in Berlin-Adlershof in Juli 2004 and obtained the PhD degree in August 2008. In his doctoral thesis he developed a signal amplifying method for molecular gene diagnostics. The thesis was awarded with the Fischer-Nernst Dissertation Award of the Institute of Chemistry at Humboldt University. He was nominated for the Adlershof Disseration Award. He currently performs postdoctoral studies at Harvard University supported by a fellowship of the Deutsche Akademie der Naturforscher Leopoldina.

His research focus

Deoxyribonucleic acid (DNA) is the molecular carrier of genetic information. Even small changes of the genetic information can pose serious threats to human health. Many diseases such as Alzheimer, Parkinson and diverse tumour diseases are inherited. Even infectious diseases can be recognized by means of characteristic gene segments.

The close connection between genetic information and disease has lead to a constantly growing need for new methods that allow the selective detection of disease-specific DNA sequences. The target sequences typically occur in minute amounts.

Common methods of DNA detection draw upon the Polymerase Chain Reaction (PCR) in order to make multiple copies of the DNA-segment of interest. This very practical method is, however, time consuming and requires special machines. It is for this reason that many researchers seek for alternative methods, in which the presence of DNA directly triggers the amplification of a signal rather than the amplification of the DNA itself.

Tom Großmann is a chemist by training and he had the idea that the DNA target could be used as a catalyst that triggers a chemical reaction. He designed a reaction, which was sparked only when a specific DNA-segment was present. The formation of the reaction product serves as an indicator for the presence of the DNA target. In his dissertation he synthesized reactive, fluorescence modified DNA probes, which - after binding of the target DNA segment - reacted to form reaction products that showed new fluorescence properties (see image).

In an alternative format enzymatic reaction were used to detect the presence of the formed reaction products. The reactions were used to detect carcinogenic DNA sequences or RNA segemts of the HI virus. Tom Großmann showed that a single gene segment catalyzed up to 400 signal forming reactions. This enabled the detection of very minute amounts (500 attomol) of target DNA by using a procedure which is easier to perform than the Polymerase Chain Reaction.

Contact: e-mail: tom.grossmann@chemie.hu-berlin.de, homepage: www.chemie.hu-berlin.de/seitz/grossmann.htm