Scientists Establish Connection Between Life Today and Ancient Changes in Ocean Chemistry

Using protein structures for the first time in such a study, the research establishes one of the influences that geochemistry has had upon life.

The study, published in this week’s edition of the Proceedings of the National Academy of Sciences, sought to verify the theory that the rise in atmospheric oxygen some 2.3 billion years ago, and attendant shifts in ocean chemistry, led to changes in types of metals used with protein structures. Such changes are hypothesized to have led to the diversification and increased complexity of the life we see today.

Scientists Chris Dupont, Song Yang, Brian Palenik and Philip Bourne from the San Diego Supercomputer Center (SDSC), Scripps Institution of Oceanography, and the departments of chemistry and biochemistry and pharmacology at the University of California, San Diego (UCSD) analyzed the metal-binding characteristics of all known protein structures found in all kingdoms of life.

“Protein structures are ideal for this study,” Bourne said, “since they are much more conserved than protein sequences, traditionally used in such studies and, furthermore, metal binding can be inferred directly.”

Using data generated by Dupont and Yang, the group established that the three superkingdoms of life – Archaea, Bacteria and Eukarya -- all use metals differently. The differences reflect the availability of such metals in the ocean as the respective superkingdoms evolved.

The authors conclude that, “these conserved trends are proteomic imprints of changes in trace-metal bioavailability in the ancient ocean that highlight a major evolutionary shift in biological trace-metal usage.”

The changes in trace-metal availability are believed to have been brought about by the biologically caused rise in atmospheric oxygen some 2.3 billion years ago, highlighting the co-evolution of biology and geochemistry on a global scale.

“Here, a biological phenomenon, photosynthesis, changed the availability of trace metals in the oceans,” Dupont said, “resulting in a reciprocal change in biological evolution still observable today.”

The group notes that, “such studies linking the study of the earth sciences with that of the life sciences are limited and certainly no one has previously looked at this exciting area from the perspective of protein structure. We hope this will encourage others to undertake such interdisciplinary work.”

Source: University of California, San Diego

Study finds high mortality of endangered loggerhead sea turtles in Baja California
(PhysOrg.com) -- Along the southern coast of Baja California, Mexico, scientists have been counting the carcasses of endangered sea turtles for a decade as part of an effort to assess and eliminate threats to loggerhead sea turtle populations. Their findings, published this week, are shocking: almost 3,000 sea turtles were found dead along a 27-mile stretch of coast during a five-year period from 2003 to 2007.
Scientist finds coastal dead zones may benefit some species
Coastal dead zones, an increasing concern to ecologists, the fishing industry and the public, may not be as devoid of life after all. A Brown scientist has found that dead zones do indeed support marine life, and that at least one commercially valuable clam actually benefits from oxygen-depleted waters.
Tides Have Major Impact on Planet Habitability
(PhysOrg.com) -- Astronomers searching for rocky planets that could support life in other solar systems should look outside, as well as within, the so-called "habitable zone," University of Arizona planetary scientists say.
Fitness in a changing world: The genetics and adaptations of the Alaskan stickleback fish
The stickleback fish, Gasterosteus aculeatus, is one of the most thoroughly studied organisms in the wild, and has been a particularly useful model for understanding variation in physiology, behavior, life history and morphology caused by different ecological situations in the wild.
Wildfires cause ozone pollution to violate health standards, new study shows
Wildfires can boost ozone pollution to levels that violate U.S. health standards, a new study concludes. The research, by scientists at the National Center for Atmospheric Research (NCAR), focused on California wildfires in 2007, finding that they repeatedly caused ground-level ozone to spike to unhealthy levels across a broad area, including much of rural California as well as neighboring Nevada.
Deep biosphere research points to new methods for recovering petroleum
Miles below us, deep within Earth's crust, life is astir. Organisms there are not the large creatures typically envisioned when thinking of life. Instead, thriving there are microbes, the smallest and oldest form of life on Earth. Although the biological diversity of these deep biosphere microorganisms may surpass that of the more familiar surface biosphere, much about them is still unknown, including the origin of the organic compounds they consume. Arizona State University researchers are using a novel approach that integrates physical organic chemistry with organic geochemistry and biogeochemistry to uncover the source of these organic compounds.
Low voltage current to stimulate growth of coral off South Florida coast
The thunderclaps and lightning flashes of Victor Frankenstein's laboratory seem far removed from the sunshine, hotels and snorkelers of the South Florida coast. But the town of Lauderdale-by-the-Sea is pursuing the dream of using electricity to help generate life.
Deepest living fishes caught on camera for the first time
(PhysOrg.com) -- Scientists filming in one of the world's deepest ocean trenches have found groups of highly sociable snailfish swarming over their bait, nearly five miles (7700 metres) beneath the surface of the Pacific Ocean. This is the first time cameras have been sent to this depth.

Scientists Establish Connection Between Life Today and Ancient Changes in Ocean Chemistry

Related stories:

News discussion: