Infected and Protected Grapevines (IMAGE) DOE/Los Alamos National Laboratory Caption Expression of a hybrid protein blocks Pierce's disease in a grapevine. The hybrid protein (shown at the bottom right) creates pores in the membrane of the Gram-negative bacterium, Xf, that causes PD. The transgenic grapevine expressing the hybrid protein shows little or no leaf scorching as PD symptom upon Xf infection (top left) whereas the non-transgenic without the hybrid protein shows severe leaf scorching (top right). Credit Los Alamos National Laboratory Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.