Model Diatom Phycosphere TnSeq

Ecological interactions that occur between phycosphere-associated bacteria at the micron scale have the potential to influence a major fraction of annual carbon flux at the global scale, yet studying the ecology of these microenvironments remains challenging. This study cultured a transposon mutant library of Ruegeria pomeroyi DSS-3 with the living diatom Thalassiosira pseudonana CCMP 1335 as the sole source of organic matter, in the presence or absence of other heterotrophic bacterial species (Vibrio hepatarius HF70 & Marivivens donghaensis HF1). Transposon sequencing allowed for measurements of mutant fitness that indicated cell-cell interactions initiated in the multi-bacterial phycospheres