Center for Life in Extreme Environments Department of Biology

image of Dr. Stedman

Room 466, SRTC (Map)


(503) 725-3253 (Office)
(503) 725-3888
kstedman at
U.S. Mail:
Portland State University, Biology
P.O. Box 751, Portland, OR 97207-0751
Street Address Courier:
1719 SW 10th Avenue, Room 246
Portland, Oregon 97201

Research Overview

Our research focuses on viruses of the extremely thermophilic archaeon (also known as archaebacteria) Sulfolobus and other viruses in volcanic hot springs. These viruses are completely different, both in structure and sequence, from any other known viruses. We are interested in how these viruses and their hosts function at very high temperatures (80C = 176F) and high acidity (pH below 4). We use genetic, genomic, structural and biochemical tools to answer these questions.

Recently we discovered a completely new group of viruses in an acidic hot lake that appears to have formed by an unprecedented RNA-DNA recombination event.

While looking for virus fossils, we have discovered a way to reversibly inactivate viruses, which may revolutionize vaccine formulation, potentiallly saving millions of lives.

We use Sulfolobus viruses as tools to develop molecular genetics for extremely thermophilic Archaea. We are also very interested in transcriptional regulation in Sulfolobus, since there are striking parallels to transcriptional regulation in eukaryotic cells, including humans. Sulfolobus is however a much more tractable system for studying these basal transcriptional mechanisms. MORE (and pictures)

Mt. Saint Helens from the Stedman Lab, March 23, 2003. KMS

In Memoriam Wolfram Zillig

Last Updated: 15 Nov 13