The Horizontally Transferred Arginine Kinase in Myxococcus Xanthus Has Evolved Roles in Multiple Physiological Processes

Abstract

Arginine kinase (AK) is a member of the phosphagen kinase family that is involved in energy homeostasis in a range of animal and protozoan species. However, recent studies have shown that some bacterial species have acquired AKs through horizontal gene transfer (HGT), raising the question as to what role they may play in bacterial systems. A recent study with one of these bacterial species, the soil bacteria Myxococcus xanthus, knocked out the endogenous AK to reveal several phenotypes, including diminished recovery from certain stressors and an unexpected role in the sporulation response induced by starvation conditions characteristic to the myxoccocales family. We have expanded upon these initial observations, identifying another novel phenotype in which the deletion strain is unexpectedly no longer recognized as kin by the non‐deletion strain. To further investigate how this AK has evolved in this system, we asked whether a heterologous AK could rescue the deletion strain. Our results will help us determine if the myxococcus AK has uniquely evolved after transmission and acquired novel traits not seen in other AKs.