Researchers at the University of Washington map the localization pattern of nearly every protein in a bacterial cell for its entire cell cycle, a new tool for discovering how bacteria coordinate the timing and location of subcellular processes
Not unlike an urban restaurant, the success of a bacterial cell depends on three things: localization, localization and localization. But the complete set of controls by which bacteria control the movement of proteins and other essential biological materials globally within the confines of their membrane walls has been something of a mystery. Now, researchers at the University of Washington have parsed out the localization mechanisms that E. coli use to sort through and organize their subcellular components.
"Despite their small size and relative simplicity, bacterial cells appear to possess a robust and complex level of subcellular organization, both spatially and temporally, that was once thought to only exist in more complex organisms," said Nathan Kuwada, a postdoctoral fellow in the lab of Paul Wiggins at the University of Washington.
"We wanted to know how many mechanisms bacteria possess to localize subcellular components, and to answer this question, we set out to image the localization pattern of nearly every protein in a bacterial cell for the entire cell cycle."
Kuwada will describe the group's findings this week at the Biophysical Society's 59th annual meeting in Baltimore, Md.
E. coli localize nearly one-fifth of their proteins to specific subcellular sites, but until now, the cell-cycle localization behavior of only a small subset of proteins had been characterized in detail.
Kuwada and his colleagues sought to remedy this by imaging an existing library of green-fluorescent protein fusions in E. coli by use of a high-throughput live-cell imaging scheme. This allowed them to image close to a thousand individual protein fusions in growing cells for 6-8 hours, providing them with hundreds of complete cell cycles for each protein.
Using custom image processing software, the researchers processed and organized the thousands of images from each experiment, allowing them to quantitatively compare the localization patterns on a genomic scale. The researchers also developed a public online database with all of their raw and processed data in a browsable and searchable form at: http://mtshasta.phys.washington.edu/localizome
Rather than a small number of patterns combining in various permutations determined by function, the researchers found that bacteria possess a large number of distinct patterns with subtle spatial and temporal differences.
For example, Kuwada and his colleagues also observed that the DNA-binding proteins were asymmetrically distributed towards the daughter cell during cell divisions, despite the morphological symmetry between parent and daughter cells.
"Although the asymmetry is somewhat weak, it is still statistically significant and we think it must have an exciting biological significance," Kuwada said. "This finding, which is only observable using our complete-cell-cycle approach, potentially has many biological consequences that we are currently trying to better understand."
Future work for Kuwada and his colleagues includes further exploring the specific mechanisms that drive subcellular organization, through targeting the behavior of specific groups of proteins such as transcription factors with increased precision.
The presentation, "Global characterization of transcription factor localization and partitioning in Escherichia coli" by Nathan J. Kuwada and Paul A. Wiggins, is at 1:45 PM, on Sunday, February 8, 2015, at the Baltimore Convention Center, in Hall C, poster 383. ABSTRACT: http://bit.ly/1KkOgN0
ABOUT THE MEETING
Each year, the Biophysical Society Annual Meeting brings together more than 6,500 researchers working in the multidisciplinary fields representing biophysics. With more than 3,600 poster presentations, over 200 exhibits, and more than 20 symposia, the BPS Annual Meeting is the largest meeting of biophysicists in the world. Despite its size, the meeting retains its small-meeting flavor through its subgroup symposia, platform sessions, social activities and committee programs. The 59th Annual Meeting will be held at the Baltimore Convention Center.
The Biophysical Society invites professional journalists, freelance science writers and public information officers to attend its Annual Meeting free of charge. For press registration, contact Ellen Weiss at or Jason Bardi at 240-535-4954.
ABOUT THE SOCIETY
The Biophysical Society, founded in 1958, is a professional, scientific Society established to encourage development and dissemination of knowledge in biophysics. The Society promotes growth in this expanding field through its annual meeting, bi-monthly journal, and committee and outreach activities. Its 9,000 members are located throughout the U.S. and the world, where they teach and conduct research in colleges, universities, laboratories, government agencies, and industry.
For more information on the Society, or the 2015 Annual Meeting, visit http://www.biophysics.org
Jason Socrates Bardi, AIP
Jason Socrates Bardi, AIP | newswise
Discovery of a Key Regulatory Gene in Cardiac Valve Formation
24.05.2017 | Universität Basel
Carcinogenic soot particles from GDI engines
24.05.2017 | Empa - Eidgenössische Materialprüfungs- und Forschungsanstalt
Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.
The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....
An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.
We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...
Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.
Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...
An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...
In the race to produce a quantum computer, a number of projects are seeking a way to create quantum bits -- or qubits -- that are stable, meaning they are not much affected by changes in their environment. This normally needs highly nonlinear non-dissipative elements capable of functioning at very low temperatures.
In pursuit of this goal, researchers at EPFL's Laboratory of Photonics and Quantum Measurements LPQM (STI/SB), have investigated a nonlinear graphene-based...
24.05.2017 | Event News
23.05.2017 | Event News
22.05.2017 | Event News
24.05.2017 | Physics and Astronomy
24.05.2017 | Physics and Astronomy
24.05.2017 | Event News