Signposts Along the Chromosomal Highway: How FtsK Finds its Target

 


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Air date: Wednesday, May 30, 2007, 3:00:00 PM
Category: Wednesday Afternoon Lectures
Runtime: 75 minutes
NLM Title: Signposts along the chromosomal highway : how FtsK finds its target [electronic resource] / Carlos Bustamante.
Series: NIH director's Wednesday afternoon lecture series
Author: Bustamante, Carlos.
National Institutes of Health (U.S.)
Publisher: [Bethesda, Md. : National Institutes of Health, 2007]
Other Title(s): NIH director's Wednesday afternoon lecture series
Abstract: (CIT): DNA translocases are molecular motors that move rapidly along DNA using adenosine triphosphate as the source of energy. FtsK is a membrane-bound and septum-localized E. coli translocase that coordinates cell division with chromosome segregation. We directly observed the movement of purified FtsK, an Escherichia coli translocase, on single DNA molecules. The protein moves at 5 kilobases per second and against forces up to 60 piconewtons, and locally reverses direction without dissociation. On three natural substrates, independent of its initial binding position, FtsK efficiently translocates over long distances to the terminal region of the E. coli chromosome, as it does in vivo. Our results imply that FtsK is a bidirectional motor that changes direction in response to short, asymmetric directing DNA sequences. Moreover, single molecule observations together with an informatics analysis strongly suggest a particular octamer as the most likely FtsK Recognition Sequence or FRS. Direct testing of this sequence confirms its assignment. Finally, we have discovered the FtsK domain responsible for recognizing and reading the FRS. Carlos Bustamante received a B.S. degree from Cayetano Heredia University in Lima, Peru, a Masters in Biochemistry from San Marcos University, and a Ph.D. in Biophysics in 1981 from the University of California, Berkeley. Since 1994, Dr. Bustamante has held an appointment as a Howard Hughes Medical Institute Investigator. In 1998, he became the director for the Advanced Microscopies Department at Lawrence Berkeley National Laboratory, and a Professor of Physics, Professor of Chemistry, as well as of Molecular and Cell Biology at Berkeley. His research interests include single molecule manipulation methods and their application for the investigation of various biochemical processes: torque measurements on single DNA molecules, reversible folding of single RNA and protein molecules by force, and the mechanochemistry of nucleic-acid binding molecular motors. He was nominated as America's Best in Time magazine (2001), received the Biological Physics Prize of the American Physical Society (2002), and accepted the Alexander Hollaender Award in Biophysics from the National Academy of Science (2004). He also received the Hans Neurath Prize of the Protein Society (2004), the Richtmyer Memorial Lecture Award by the American Association of Physics Teachers (2005), and a Honorary Doctorate (Honoris Causa) from the University of Chicago (2005). Dr. Bustamante has given well over 400 presentations and lectures and has published over 200 papers in several journals such at PNAS, Nature, Science, and Cell. He currently serves as a member of the Science Advisory Board of the Searle Scholars Program and he is also a member of the National Academy of Sciences. He has served in the Science Advisory Committee of the Burroughs-Wellcome Fund, and is on their Board of Directors. He also holds several other advisory roles within the University of California, Berkeley and the larger scientific community. The NIH Director's Wednesday Afternoon Lecture Series includes weekly scientific talks by some of the top researchers in the biomedical sciences worldwide.
Subjects: Escherichia coli Proteins--metabolism
Membrane Proteins--metabolism
Publication Types: Government Publications
Lectures
Download: Download Video
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NLM Classification: QW 52
NLM ID: 101308593
CIT File ID: 13846
CIT Live ID: 5203
Permanent link: http://videocast.nih.gov/launch.asp?13846

 

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