Integration of gene exchange into a bacterium’s physiology

Gene transfer agents (GTAs) are bacteriophage-like particles produced by some prokaryotes that exclusively package small fragments of cellular DNA. Production of GTA particles by the alphaproteobacterium Rhodobacter capsulatus occurs in a small subset of the population (<3%), with these cells lysing to release particles that can then transfer the packaged DNA to other cells in the population. The production of GTAs in R. capsulatus is controlled by several regulatory systems and coordinated with the capability of non-producing cells to become competent to receive DNA from the GTA particles.