Skip to main content

A microscopic topographic map of cellular function

The flow of traffic through our nation's highways and byways is meticulously mapped and studied, but less is known about how materials in cells travel. Now, a team of researchers at the University of Missouri is challenging prior theories about how material leaves the inside of an E.coli cell. This discovery could have important implications for how we treat diseases.
"Proteins are like vehicles that can carry information and materials in cells," said Gavin King, an associate professor of physics in the MU College of Arts and Science and joint associate professor of biochemistry. "We focused on the cells of E.coli, which have two membranes. We observed that when proteins exit the cell's inner membrane, the cell adjusts the way it transfers the protein through the channel depending on the type of protein being transported."
King worked with Linda Randall, professor emerita of biochemistry. Randall verified the transportation function of E.coli cells outside of their natural environment. Once verified, the samples were sent to King where King's team used an atomic force microscope to study the movement of the E.coli proteins. Unlike previous studies where proteins were frozen, the atomic force microscope allows researchers to observe the proteins moving in a fluid environment that closely resembles their natural environment.
"Before our study there were two ways of describing how proteins moved across the cell membrane -- either a piston-live movement similar to a car's engine, or a more perpetual motion known as the Brownian ratchet," King said. "Neither model accounted for the differences based on the type of protein being transported. Just as different types of vehicles move differently so do different types of proteins. The maps we made to depict the proteins' movement suggest nature might be more complex than previously thought."
These findings provide basic knowledge on how a cell sends and receives material and information. For instance, a drug can pass through membranes in order to affect a cell, and similarly, some information must pass through membrane channels to exit the cell. While other cells besides E.coli may not have E.coli's exact protein transportation system, King said a similar system exists in all cells.
Story Source:
Materials provided by University of Missouri-Columbia.
Note: Content may be edited.

Comments

Post a Comment

Popular posts from this blog

Home births as safe as hospital births: International study suggests

A large international study led by McMaster University shows that low risk pregnant women who intend to give birth at home have no increased chance of the baby's perinatal or neonatal death compared to other low risk women who intend to give birth in a hospital. The results have been published by  The Lancet 's  EClinicalMedicine  journal. "More women in well-resourced countries are choosing birth at home, but concerns have persisted about their safety," said Eileen Hutton, professor emeritus of obstetrics and gynecology at McMaster, founding director of the McMaster Midwifery Research Centre and first author of the paper. "This research clearly demonstrates the risk is no different when the birth is intended to be at home or in hospital." The study examined the safety of place of birth by reporting on the risk of death at the time of birth or within the first four weeks, and found no clinically important or statistically different risk between home...
Post a Comment
Read more

Dark matter may be older than the Big Bang

Dark matter, which researchers believe make up about 80% of the universe's mass, is one of the most elusive mysteries in modern physics. What exactly it is and how it came to be is a mystery, but a new Johns Hopkins University study now suggests that dark matter may have existed before the Big Bang. The study, published August 7 in  Physical Review Letters , presents a new idea of how dark matter was born and how to identify it with astronomical observations. "The study revealed a new connection between particle physics and astronomy. If dark matter consists of new particles that were born before the Big Bang, they affect the way galaxies are distributed in the sky in a unique way. This connection may be used to reveal their identity and make conclusions about the times before the Big Bang too," says Tommi Tenkanen, a postdoctoral fellow in Physics and Astronomy at the Johns Hopkins University and the study's author. While not much is known about its origins,...
Post a Comment
Read more

Scientists challenge notion of binary sexuality with naming of new plant species

A collaborative team of scientists from the US and Australia has named a new plant species from the remote Outback. Bucknell University biology postdoctoral fellow Angela McDonnell and professor Chris Martine led the description of the plant that had confounded field biologists for decades because of the unusual fluidity of its flower form. The discovery, published in the open access journal  PhytoKeys , offers a powerful example of the diversity of sexual forms found among plants. The new species of bush tomato discovered in remote Australia provides a compelling example of the fact that sexuality among Earth's living creatures is far more diverse -- and interesting -- than many people likely realize. Bucknell University postdoctoral fellow Angela McDonnell and biology professor Chris Martine led the study following an expedition last year to relocate populations of the new plant, which were first noted by Australian botanists during the 1970s. Herbarium specimens from th...
Post a Comment
Read more