Gustafsson R, Berntsson RP, Martínez-Carranza M, El Tekle G, Odegrip R, Johnson EA, Stenmark P
FEBS Lett. - (-) - [2017-10-25; online 2017-10-25]
Botulinum neurotoxins are highly toxic substances and are all encoded together with one of two alternative gene clusters, the HA or the OrfX gene cluster. Very little is known about the function and structure of the proteins encoded in the OrfX gene cluster, which in addition to the toxin contains 5 proteins (OrfX1, OrfX2, OrfX3, P47 and NTNH). We here present the structures of OrfX2 and P47, solved to 2.1Å and 1.8Å respectively. We show that they belong to the TULIP protein superfamily, which are often involved in lipid binding. OrfX1 and OrfX2 were both found to bind phosphatidyl-inositol lipids. This article is protected by copyright. All rights reserved.