Pawel Penczek, Ph.D.
Professor, Biochemistry and Molecular Biology
Director, Structural Biology Research Center
University of Texas - Houston Medical School
M.S., Medical Physics, Warsaw University (1979)
Ph.D., Physics, Warsaw University (1988)
Postdoc: Wadsworth Center, Albany, NY (Prof. J. Frank)
We are interested in the determination of three-dimensional structures of large macromolecular complexes with low or non-existing symmetry in single-particle form using stain and cryo-electron microscopy (cryo-EM) and computer image processing techniques.
Our main area of interest is high-resolution cryo-EM and the development of efficient and largely automatic tools for single particle analysis and three-dimensional reconstruction. Due to a very low Signal-To-Noise Ratio of EM data, there is a necessity to collect and merge large numbers (in excess of 100,000) of individual particle images. Thus, in our approach we will focus on automatic particle picking utilities that should be able to cope with a large number of micrographs under various noise conditions.
Unconstrained by crystal packing, the molecule in a single particle specimen can be thought to exhibit the entire range of native conformations. The ability to find the structure of each conformer is one of the most important potential assets of 3D cryo-EM of single particles. On the other hand, the realization of high resolution for each of these conformers poses daunting problems of data collection and processing, considering the statistical requirements stated before. Therefore, we are also interested in the development of efficient and robust computational methods of resolution refinement in the presence of multiple conformational or binding states.
- Mileykovskaya E, Penczek PA, Fang J, Mallampalli VK, Sparagna GC and Dowhan W. Arrangement of the respiratory chain complexes in Saccharomyces cerevisiae supercomplex III2IV2 revealed by single particle cryo-electron microscopy. J Biol Chem, 287(27):23095-103 (2012). PubMed
- Yang Z, Fang J, Chittuluru J, Asturias FL and Penczek PA. Iterative stable alignment and clustering of 2D transmission electron microscope images. Structure, 20(2):237-47 (2012). PubMed
- Penczek PA, Kimmel M and Spahn CM. Identifying conformational states of macromolecules by eigen-analysis of resampled cryo-EM images. Structure, 19(11):1582-90 (2011). PubMed
- Penczek PA. Resolution measures in molecular electron microscopy. Methods Enzymol, 482:73-100 (2010). PubMed
- Penczek PA. Image restoration in cryo-electron microscopy. Methods Enzymol, 482:35-72 (2010). PubMed
- Penzcek PA. Fundamentals of three-dimensional reconstruction from projections. Methods Enzymol, 482:1-33 (2010). PubMed
- Zhang W, Kimmel M, Spahn CM and Penczek PA. Heterogeneity of large macromolecular complexes revealed by 3D cryo-EM variance analysis. Structure, 16(12):1770-6 (2008). PubMed
For more publications, see listing on PubMed.
Department: Biochemistry and Molecular Biology
Address: 6431 Fannin, MSB 6.128
Houston, TX 77030
Additional Links: University of Texas Houston Medical School