Tracing evolution’s blueprint: Minimal genome life and the engineering of synthetic endosymbiosis

Tracing evolution’s blueprint: Minimal genome life and the engineering of synthetic endosymbiosis Roksana Riddle and Christopher H. Contag from Michigan State University discuss the concept of endosymbiosis, how it has evolved, and present strategies to engineering endosymbionts and their applications in developing innovative therapies. Endosymbiogenesisis is the emergence of mutually beneficial relationships between cells in which one lives inside the other to become a holobiont. Endosymbiosis has occurred naturally when intracellular parasites, dependent on host health, begin providing benefits to that host. While this jump may seem like an impossible change from harm to benefit, a study of five obligate intracellular parasites showed a loss of gene redundancy, elimination of metabolic genes, and, most importantly, diminished defense mechanisms when compared to free-living bacteria such as E. coli (Sakharkar et al., 2004). If a parasite is host-dependent, then any defensive genes that harm the host further would alert the immune system, resulting in the destruction of the partnership.