In order to cause disease, the human pathogen Staphylococcus aureus must adapt to the changing host environment. Many of these adaptations are mediated through two-component signal transduction systems (TCSs) that coordinate gene expression in response to environmental stimuli.

Much like humans eat food in order to obtain essential nutrients, bacteria acquire nutrients by importing them. An essential nutrient for life is zinc, which cannot be manufactured, and therefore must be obtained from the environment. However, the availability of zinc is frequently limited. This is exemplified by a defense mechanism, nutritional immunity, used by the immune system to prevent infections in which the body withholds metals, such as zinc, to combat invading bacteria.

An investigation of two closely related proteins from a pathogenic bacterium has illustrated for the first time how evolution can shape the use of essential metals by enzymes.

A new study, published in mBio, exposes a zinc-import system in bacteria that could contribute to their ability to cause infection.

The study looked at how the bacterium Staphylococcus aureus, which can infect virtually all of the tissues in the human body, competes with the immune system for the essential nutrient zinc.