Electron transport between species discovered in deep-sea research

Researchers at the California Institute of Technology have discovered two microbial species capable of sharing the energy needed to consume methane through electron transfer without direct contact.

Researchers say it is the first time interspecies electron transport, or the external passing of electrons from one type of cell to another, has been discovered among microorganisms in a natural setting.

The research, detailed in the latest issue of Nature, was led by Professor of Geobiology Victoria Orphan, whose lab has studied the relationship between these two species in deep-sea methane seeps for the last two decades.

A species of bacteria and a species of archaea work together in syntrophy to consume large quantities of methane, which discharges from the ocean floor.

Methane, or CH4, is a greenhouse gas and -- when released into ocean water and air in large quantities -- a primary contributor to climate change.

In order to complete their research on location at the bottom of the ocean, scientists used research submersible Alvin to collect samples of the microbes from seep sediments to be returned to the lab for testing. The team incorporated fluorescent DNA stains to note the two specific microbes and study their proximity in various bacterial communities.