@article{b7eaaf1882d446ffa6ecc630ce7a4b21,
title = "De novo phasing with X-ray laser reveals mosquito larvicide BinAB structure",
abstract = "BinAB is a naturally occurring paracrystalline larvicide distributed worldwide to combat the devastating diseases borne by mosquitoes. These crystals are composed of homologous molecules, BinA and BinB, which play distinct roles in the multi-step intoxication process, transforming from harmless, robust crystals, to soluble protoxin heterodimers, to internalized mature toxin, and finally to toxic oligomeric pores. The small size of the crystals - 50 unit cells per edge, on average - has impeded structural characterization by conventional means. Here we report the structure of Lysinibacillus sphaericus BinAB solved de novo by serial-femtosecond crystallography at an X-ray free-electron laser. The structure reveals tyrosine- and carboxylate-mediated contacts acting as pH switches to release soluble protoxin in the alkaline larval midgut. An enormous heterodimeric interface appears to be responsible for anchoring BinA to receptor-bound BinB for co-internalization. Remarkably, this interface is largely composed of propeptides, suggesting that proteolytic maturation would trigger dissociation of the heterodimer and progression to pore formation.",
author = "Colletier, {Jacques Philippe} and Sawaya, {Michael R.} and Mari Gingery and Rodriguez, {Jose A.} and Duilio Cascio and Brewster, {Aaron S.} and Tara Michels-Clark and Hice, {Robert H.} and Nicolas Coquelle and S{\'e}bastien Boutet and Williams, {Garth J.} and Marc Messerschmidt and DePonte, {Daniel P.} and Sierra, {Raymond G.} and Hartawan Laksmono and Koglin, {Jason E.} and Hunter, {Mark S.} and Park, {Hyun Woo} and Monarin Uervirojnangkoorn and Bideshi, {Dennis K.} and Brunger, {Axel T.} and Federici, {Brian A.} and Sauter, {Nicholas K.} and Eisenberg, {David S.}",
note = "Funding Information: We acknowledge the help of the following people during data collection: S. Lee, J. Koralek, R. Shoeman, S. Botha, B. Doak and O. Zeldin. We thank A. Volveda for advice regarding sequence-wise Fourier difference map integration; J. Brooks-Bartlett and E. Garman for help with dose calculations; and M. Weik for discussions and continuing support. We thank the HCIA program of HHMI, the W.M. Keck Foundation (grant 2843398), the NIH (grant AG-029430), National Science Foundation (grant MCB 0958111) and DOE (DE-FC02-02ER63421) (to D.S.E.), the France Alzheimer Foundation (FA-AAP-2013-65-101349) and the Agence Nationale de la Recherche (ANR- 12-BS07-0008-03) (to J.-P.C.), NIH grants GM095887 and GM102520 for dataprocessing methods (to N.K.S.), and NIH grant AI45817 (to B.A.F.). Support by the CNRS (PEPS-SASLELX-2013, PEPS-SASLELX-2014) funded travel to LCLS. Use of the LCLS at SLAC National Accelerator Laboratory, is supported by the US Department of Energy, Office of Science, and Office of Basic Energy Sciences under contract no. DE-AC02-76SF00515. The CXI instrument was funded by the Linac Coherent Light Source Ultrafast Science Instruments project, itself funded by the DOE Office of Basic Energy Sciences. Parts of the sample injector used at LCLS for this research were funded by the National Institutes of Health, P41GM103393, formerly P41RR001209. Publisher Copyright: {\textcopyright} 2016 Macmillan Publishers Limited, part of Springer Nature. All rights reserved.",
year = "2016",
doi = "10.1038/nature19825",
language = "English (US)",
volume = "539",
pages = "43--47",
journal = "Nature",
issn = "0028-0836",
publisher = "Nature Publishing Group",
number = "7627",
}