Nav: Home

Structure Of The Plasma Membrane Proton Pump Offers A First Glimpse Of The Mechanism Of Ion Pumping Across Membranes

April 27, 1998

A research team from the Max Planck Institute of Biophysics in Frankfurt/Germany, and the University of North Carolina, Chapel Hill/NC, has determined the structure of the plasma membrane proton ATPase at a resolution of about 0.8 nm by electron cryomicroscopy of two-dimensional crystals (Nature, vol. 392, 23 April 1998, 840).

The proton ATPase is a membrane protein which uses energy derived from ATP hydrolisis to pump protons out of the cell, there by controlling its internal pH. Similar proteins control the heart rhythm, the action potential of nerve cells, and muscle contraction. All these ion pumps work in the same way as the proton ATPase and are likely to have similar structures.

Manfred Auer and Werner Kühlbrandt of the Department of Structural Biology at the Max Planck Insitute of Biophysics developed a new method to grow two-dimensional crystals on a carbon support film and used these for structure determination by electron cryo-microscopy, at a resolution of 0.8 nm. Gene A. Scarborough, from the Department of Pharmacology at the University of North Carolina, provided the protein of which he was able to grow three-dimensional crystals, thus providing the essential starting point for the 2D crystallization experiments.

The structure of the closely related calcium ATPase, also determined by electron microscopy at comparable resolution, is reported in the same issue of nature (Zhang et al, nature, vol. 392, 23 April 1998, 835). Interestingly, the two structures are similar in the transmembrane domain, but they appear to differ significantly in the large cytoplasmic region. Presumably, the differences in the two structures represent the conformational change that occurs upon ion binding. Such ligand induced conformational changes are almost certainly intimately involved in the ion occlusion and molecular mechanisms of ion translocation catalyzed by this important family of ion pumps.


Related Nature Articles:

Energized by enzymes -- nature's catalysts
Scientists at Pacific Northwest National Laboratory are using a custom virtual reality app to design an artificial enzyme that converts carbon dioxide to formate, a kind of fuel.
Mother nature and child development
A world first review of the importance of nature play could transform children's play spaces, supporting investment in city and urban parks, while also delivering important opportunities for children's physical, social and emotional development.
How nature tells us its formulas
A team from TU Wien and the University of Heidelberg has developed methods with which these models can be directly obtained from experimental measurements.
Reconnecting with nature key for sustainability
People who live in more built up areas and spend less free-time in nature are also less likely to take actions that benefit the environment, such as recycling, buying eco-friendly products, and environmental volunteering.
Limiting the loss of nature
With only about half of Earth's terrestrial surface remaining as natural vegetation, a University of Queensland-led team has proposed an international goal to halt its continued loss.
Combatting air pollution with nature
Air pollution is composed of particles and gases that can have negative impacts on both the environment and human health.
Nature documentaries increasingly talk about threats to nature, but still don't show them
Researchers analyzing recent BBC and Netflix nature documentaries found that although they increasingly mention threats to nature, visual depictions of these threats remain scarce, potentially misleading audiences on the state of the natural world.
Selective antibiotics following nature's example
Chemists from Konstanz develop selective agents to combat infectious diseases -- based on the structures of natural products
Measuring the laws of nature
One of the fundamental physical constants, the 'weak axial vector coupling constant' (gA), has now been measured with very high precision for the first time.
Using nature to adapt to climate change
Climate change poses major threats to people around the world.
More Nature News and Nature Current Events

Trending Science News

Current Coronavirus (COVID-19) News

Top Science Podcasts

We have hand picked the top science podcasts of 2020.
Now Playing: TED Radio Hour

Listen Again: Reinvention
Change is hard, but it's also an opportunity to discover and reimagine what you thought you knew. From our economy, to music, to even ourselves–this hour TED speakers explore the power of reinvention. Guests include OK Go lead singer Damian Kulash Jr., former college gymnastics coach Valorie Kondos Field, Stockton Mayor Michael Tubbs, and entrepreneur Nick Hanauer.
Now Playing: Science for the People

#562 Superbug to Bedside
By now we're all good and scared about antibiotic resistance, one of the many things coming to get us all. But there's good news, sort of. News antibiotics are coming out! How do they get tested? What does that kind of a trial look like and how does it happen? Host Bethany Brookeshire talks with Matt McCarthy, author of "Superbugs: The Race to Stop an Epidemic", about the ins and outs of testing a new antibiotic in the hospital.
Now Playing: Radiolab

Dispatch 6: Strange Times
Covid has disrupted the most basic routines of our days and nights. But in the middle of a conversation about how to fight the virus, we find a place impervious to the stalled plans and frenetic demands of the outside world. It's a very different kind of front line, where urgent work means moving slow, and time is marked out in tiny pre-planned steps. Then, on a walk through the woods, we consider how the tempo of our lives affects our minds and discover how the beats of biology shape our bodies. This episode was produced with help from Molly Webster and Tracie Hunte. Support Radiolab today at