About Dr. Siemann

Dr. Stefan Siemann grew up in Paderborn, a mid-sized city in the eastern part of North Rhine-Westphalia, Germany. After obtaining his high school degree at the Theodorianum (one of the oldest schools in the world), he studied chemistry at the University of Paderborn. Near the end of his undergraduate studies, he went to the University of Waterloo (Canada) for a year as part of a scholarship-sponsored foreign exchange program. During this time, Dr. Siemann took his first biochemistry course with Dr. Thammaiah Viswanatha, who later became his long-time mentor.

After a brief return to Paderborn to complete his undergraduate degree, Dr. Siemann went back to UWaterloo to commence his Diploma/M.Sc. studies under the supervision of Drs. Viswanatha (Waterloo) and Karsten Krohn (Paderborn), working on the lysine:N⁶-hydroxylase, an enzyme in the biosynthetic pathway of the iron-scavenging siderophore aerobactin.

Following completion of his degree, Dr. Siemann started his Ph.D. studies on nitrogenases under the supervision of renowned inorganic chemist Dr. Achim Müller at the University of Bielefeld, Germany. Together with Dr. Klaus Schneider (the team-lead of the bioinorganic chemistry branch of the Mueller group), Dr. Siemann worked on molybdenum- and iron-only nitrogenases, their spectral characterization, and on iron-molybdenum cofactor biosynthesis. During his time in the Müller group, Dr. Siemann developed an interest in studying the effects of metal substitution on metalloenzyme function (in particular, molybdenum-to-tungsten in nitrogenase). Similar metal replacement studies turned out to be one of the main focal points of Dr. Siemann’s research later on (especially at Laurentian University)

After obtaining his Ph.D. in chemistry in 2000, Dr. Siemann returned as a post-doctoral fellow to UWaterloo to work with Drs. Gary Dmitrienko, Anthony Clarke and T. Viswanatha on the inhibition and mechanism of zinc-dependent metallo-β-lactamases (enzymes partly responsible for the emergence and spread of the microbial resistance to β-lactam antibiotics). During this time, Dr. Siemann became interested in zinc enzymes, their catalytic mechanisms, and the role of the metal, an interest which he further developed at Laurentian University.

In 2004, Dr. Siemann took an assistant professorship in the Dept. of Chemistry and Biochemistry at Laurentian University, where he originally established a research group focusing on anthrax lethal factor (a zinc protease). Since then, his research has expanded to studies on a variety of zinc proteins including metallo-β-lactamases (with his long-time collaborator Dmitrienko), thermolysin, carboxypeptidase A and others.