The enemy of my enemy

Abstract

Ticks and other blood-feeding animals, such as the species Ixodes scapularis, the vector of Lyme disease, reside on their hosts for extended periods of time, so they must ward off pathogenic members of the host’s microbiome. I. scapularis harbors the gene for an antibacterial enzyme, Dae2, that was acquired via horizontal gene transfer of the bacterial homolog Tae2, which is used to degrade cell wall peptidoglycan (PG). To understand the function of Dae2 in these ticks, Hayes and Radkov et al. characterized the tick Dae2 and a bacterial Tae2 and investigated the effects of Dae2 on bacteria in the human skin microbiome. The structure of Tae2 and a homology model of Dae2 both adopt an amidase fold, but differences in Tae2