Tim Soderberg

Associate Professor of Chemistry
University of Minnesota, Morris

Office: Science 1320
Phone: (320) 589-6331
Email: soderbt

I am the Organic/Bioorganic person in the UMM Chemistry Discipline. I received a B.A. in English from Amherst College in 1987, and a California teaching credential from San Francisco State University in 1989. After teaching English as a Second Language in Tokyo, Japan for about five years, I returned to the United States and enrolled at Sonoma State University where I completed all of the undergraduate Chemistry, Calculus, and Physics courses necessary to enter a graduate Chemistry program. I came here in the Fall of 2000 after receiving my Ph.D. in Biological Chemistry from the University of Utah under the direction of Professor C. Dale Poulter. My graduate research focused on the enzymology of two prenyltransferase enzymes: one that modifies tRNA, and one that is involved in the early biosynthesis of ether-linked membrane lipids in archaea. My current research at UMM (see below) involves trying to understand the role of the pentose phosphate pathway enzymes in archaeal species, and much of my time recently has been spent working on the development of a new organic chemistry textbook in which the central focus is on molecules and reactions of biological interest. Click here to learn more about this project.

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Weekly Schedule
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Courses currently taught:
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Research

My research interests lie in the area of bioorganic chemistry, the organic chemistry that occurs via enzymatic catalysis in biological systems. More specifically, I am interested in trying to better understand biochemical pathways in a group of organisms called Archaea. These microscopic prokaryotes, which make up a separate kingdom of life distinct from Bacteria and Eukarya, are fundamentally different- in terms of their genetic evolutionary history and in many cases their biochemistry- from organisms in the two other kingdoms. Archaea thrive in conditions that until recently were thought to be incompatible with living things: in the boiling, sulfurous waters of hot springs, for example, in 4M salt water, and near geothermal vents thousands of feet under the ocean, far from any sources of light or molecular oxygen.

As part of the advent of massive DNA sequencing projects, several complete genetic blueprints for archaeal species have been published, revealing that the archaea are missing many genes that were previously thought to be essential for all living things.   Many archaeal species, for example, are missing genes encoding enzymes of the pentose phosphate pathway (PPP), a series of biochemical reactions that converts abundant 6-carbon sugars   like glucose and fructose into important five and four-carbon sugars. Ribose-5-phosphate, a five-carbon sugar, is required for the synthesis of DNA and RNA, while erythrose-4-phosphate, a four-carbon sugar, is required for making amino acids such as phenylalanine and tyrosine.   The enzymes of the PPP are the only known route to ribose and erythrose, so the source of these critical precursor sugars in archaea is still unknown.   It is possible that the genes may exist but are not recognizable by current sequence analysis techniques. Alternate pathways may also play key roles.   The goal of my project is to learn more about the PPP in archaea, and to explain how the sugar precursors for DNA and amino acids are synthesized in these species.

A recently completed functional genomics project has resulted in a possible explanation for the enigmatic patterns of inheritance observed for the PPP genes in archaeal genomes, and suggests that, in some archaeal species which are missing the PPP genes, ribose phosphate synthesis may be accomplished instead by enzymes of the ribulose monophosphate pathway. A paper describing this study has been published in ARCHAEA (click here to read).

Both of these papers have been cited in a recently published book, Archaea: new models of prokaryotic biology (Paul Blum, ed.) and also in numerous research reports and reviews.

This research has been supported by start-up funding from the University of Minnesota, Morris, and by a Cottrell College Science Award from the Research Corporation.

Publications:

Soderberg, T. "Biosynthesis of ribose-5-phosphate and erythrose-4-phosphate in archaea: a phylogenetic analysis of archaeal genomes" Archaea 2005, 1, 347-352.

Soderberg, T. and Alver, R. C. "Transaldolase of Methanocaldococcus jannschii" Archaea 2004, 1, 255-262.

Soderberg, T., Chen, A., and Poulter, C. D. "Geranylgeranylglyceryl phosphate synthase: characterization of the recombinant enzyme from Methanobacterium thermoautotrophicum" Biochemistry 2001, 40, 14847-14854.

Soderberg, T., and Poulter, C. D. "Escherichia coli dimethylallyl diphosphate:tRNA dimethylallyltransferase: site-directed mutagenesis of highly conserved residues" Biochemistry 2001, 40, 1734-1740.

Soderberg, T. and Poulter, C. D. "Escherichia coli dimethylallyl diphosphate:tRNA dimethylallyltransferase: essential elements for recognition of tRNA substrates within the anticodon stem-loop" Biochemistry 2000, 39, 6546-6553.

The views and opinions expressed in this page are strictly those of the page author. The contents of this page have not been reviewed or approved by the University of Minnesota.