Marine bacteria hunt with purpose

Bacteria in the ocean are incredibly numerous and play important roles in the marine ecosystem, some of which we may not yet understand. Despite their plentitude, there are many gaps in our knowledge of ocean microbes. New research sought to investigate one of the most basic aspects of the lives of marine bacteria – do they actively hunt or merely drift through the water consuming whatever they encounter? The science suggests the former. 

An international group of scientists led by researchers at the University of Technology Sydney (UTS) used microchips to peer into the world of microbes. What they discovered is that bacteria move in ways comparable to larger animals when foraging. 

“We had some idea that microbes could swim around their immediate environment to find and exploit food patches, but the only available evidence came from laboratory experiments, which are often not very realistic or representative of natural environments,” said study lead author and microbial ecologist Dr. Jean-Baptiste Raina.

“This kind of behavior had never been comprehensively examined in the environment among natural populations of microbes. Now, for the first time, we’ve been able to show that the swimming behaviour of microbes in the natural environment is governed by the attraction of bacteria to specific chemical cues, which dictates important processes and interactions that structure the base of the marine food web.”

The scientists created bacteria traps in order to investigate the microbes feeding preferences and found that certain chemicals that the bacteria consume create “feeding frenzies.” The scientists say that the behaviors and preferences of bacteria can have important implications. 

“When we think about how small a bacterium is, it is easy to dismiss the consequences of its behavior,” explained study senior author Professor Justin Seymor.

“However, because marine bacteria are so numerous and diverse, the way they find, consume and recycle chemicals in seawater can have a profound influence on processes that control global climate and the productivity of the marine food web.”

The study is published in the journal Nature.

—

By Zach Fitzner, Earth.com Staff Writer