An Ixodes scapularisProtein Disulfide Isomerase Contributes to Borrelia burgdorferiColonization of the Vector

Borrelia burgdorfericauses Lyme disease, the most common tick-transmitted illness in North America. When Ixodes scapularisfeed on an infected vertebrate host, spirochetes enter the tick gut along with the bloodmeal and colonize the vector. Here, we show that a secreted tick protein, I. scapularisprotein disulfide isomerase A3(IsPDIA3), enhances B. burgdorfericolonization of the tick gut.