Division of labor and growth during electrical cooperation in multicellular cable bacteria
Nicole M. J. Geerlings, Cheryl Karman, Stanislav Trashin, Karel As, Michiel V. M. Kienhuis, Silvia Hidalgo‐Martinez, Diana Vasquez‐Cardenas, Henricus T. S. Boschker, Karolien De Wael, Jack J. Middelburg, Lùbos Polerecký, Filip J. R. Meysman
Abstract
N-ammonia isotope labeling reveals that cells performing sulfide oxidation in deeper anoxic horizons have a high assimilation rate, whereas cells performing oxygen reduction in the oxic zone show very little or no label uptake. Accordingly, oxygen reduction appears to merely function as a mechanism to quickly dispense of electrons with little to no energy conservation, while biosynthesis and growth are restricted to sulfide-respiring cells. Still, cells can immediately switch roles when redox conditions change, and show no differentiation, which suggests that the "community service" performed by the cells in the oxic zone is only temporary. Overall, our data reveal a division of labor and electrical cooperation among cells that has not been seen previously in multicellular organisms.