Myxobacteria Cooperate to Repair Damaged Siblings

A University of Wyoming (UW) faculty member led a research team that discovered a certain type of soil bacteria can use the social behavior of outer membrane exchange (OME) to repair damaged cells and improve the fitness of the bacteria population as a whole. Dr. Daniel Wall, a UW Associate Professor in the Department of Molecular Biology, and others were able to show that damaged sustained by the outer membrane (OM) of a myxobacteria cell population was repaired by a healthy population using the process of OME. The research revealed that these social organisms benefit from group behavior that endows favorable fitness consequences among related cells. Dr. Wall says, to the research group's knowledge, this is the first evidence that a bacterium can use cell-content sharing to repair damaged siblings. "It is analogous to how a wound in your body can be healed," Dr. Wall says. "When your body is wounded, your cells can coordinate their functions to heal the damaged tissue." Dr. Wall was the senior and corresponding author on a paper, titled "Cell Rejuvenation and Social Behaviors Promoted by LPS Exchange in Myxobacteria," that was published online on May 18, 2015 in PNAS. Chris Vassallo, a UW doctoral student in molecular biology and originally from Cheyenne, Wyoming, was the paper's lead author and conducted most of the lab experiments. "During nutrient depletion, myxobacteria cooperate to build a macroscopic structure called a fruiting body," Vassallo says. "The structure resembles a tree or mushroom in appearance." A fruiting body (see image)is essentially a multicellular organism that produces dormant spores that are resistant to environmental stresses. These myxobacterial cells, in their native environments, must cope with factors that compromise the integrity of the cell, Dr. Wall says.