Science Concentrates Superlong, icebinding protein structure solved
RV
Researchers have obtained the first structure of a 600-nm-long, ice-binding protein. Few proteins are this long; one exception is the muscle protein titin, which is more than 1 µm long. Most folded proteins are 2 to 15 nm long. Ice The ice-binding proRIV tein, called Marinomonas primoryensis ice-binding protein (MpIBP), is expressed on the surface of an RIII Antarctic bacterium, which uses the protein to latch onto the underside of ice sheets. In this near-surface, sunlit location, the bacteria can cohabit with diatoms, which photosynthesize oxygen that the bacteria need. MpIBP’s single protein chain has five regions: RI, RII, RIII, RIV, and RV. Pe~120 RII repeats ter L. Davies of Queen’s Universi(~600 nm) ty in Ontario, Ilja K. Voets of Eindhoven University of Technology, and coworkers earlier obtained X-ray crystal structures of RII and RIV. They have now used X-ray crystallography, nuclear magnetic resonance, and small-angle X-ray scattering to analyze RI, RIII, RI and RV, enabling them to assemble the entire Bacterial outer structure (Sci. Adv. 2017, DOI: 10.1126/ membrane sciadv.1701440). “The disStructure of sect-and-conquer MpIBP, a protein approach allowed that the bacterium these researchers Marinomonas to gain insights primoryensis uses into how the varito attach to ice. ous modules work together to allow the bacterium to thrive in the Antarctic,” comments Karl E. Klose of the University of Texas, San Antonio. Voets points out that MpIBP grips ice in a way that is similar to how pathogenic bacteria attach to our cells. Understanding the MpIBP attachment process could thus help scientists develop a new way to block human bacterial infections, she says.—STU BORMAN
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C&EN | CEN.ACS.ORG | AUGUST 14/21, 2017
PUBLISHING
Chemistry preprint servers launched ChemRxiv beta site and ChemRN are accepting manuscripts ahead of peer review Two chemistry preprint servers have been launched in the past few weeks. ACS launched a beta version of ChemRxiv, a preprint server for the chemistry community, last week. ChemRxiv has been developed with input from ACS, the Royal Society of Chemistry, and the German Chemical Society, along with other nonprofit organizations and scientific publishers. “With strategic input from three large chemical societies, other nonprofits, and engagement with other preprint servers, ChemRxiv is truly by the chemistry community, for the chemistry community,” says Darla Henderson, assistant director of open access programs at ACS. C&EN is published by ACS. Laura L. Kiessling, chemistry professor at Massachusetts Institute of Technology and editor-in-chief of ACS Chemical Biology, championed the idea of a preprint server to her fellow ACS journal editors. A preprint server will allow scientists to disseminate their results more rapidly and will allow others to build on those results, she says. ChemRxiv is not alone in chemistry prepublication, however: Two weeks ago, publisher Elsevier announced its own chemistry preprint server, the Chemistry Research Network (ChemRN), which is part of SSRN, an electronic library serving multiple disciplines. Its introduction comes shortly after that of BioRN, a biology network launched in June that was SSRN’s first network outside the social sciences. “SSRN is in a unique position to serve the chemistry community,” says Gregg Gordon, managing director of SSRN. “We have over 20 years of experience in building community-focused networks, and we benefit from Elsevier’s knowledge, technology, and close connection to its authors.” Chemists may worry that submission to preprint servers will jeopardize later publication in a peer-reviewed journal. More than 80% of ACS journals, includ-
ing ACS Chemical Biology, already allow preprints to be published in their pages, Henderson says. The Journal of the American Chemical Society (JACS), ACS’s flagship journal, has a more restrictive policy: “Any content that has been made publicly available, either in print or electronic format, and that contains a significant amount of new information, if made part of a submitted manuscript, may jeopardize the originality of the submission and may preclude consideration for publication,” according to the journal’s website.
“The more researchers who engage with the preprint process, the more valuable the server becomes.” —Laura L. Kiessling, professor, MIT Peter J. Stang, editor-in-chief of JACS, says the journal’s editorial board will discuss the policy at its meeting at the August 2018 ACS national meeting in Boston. “Until then, the restrictive policy stays,” he says. Benjamin List, editor-in-chief of Synlett, a journal from publisher Thieme that has experimented with crowdbased reviewing, is not yet sure how to deal with preprints. “What I like about the concept is that it enables authors to decide when their work is published,” he says. “A disadvantage is that there will always be multiple versions of a paper.” He expects preprints to lead to improved quality if crowd reviewing is involved. The hope is that chemistry preprint servers will accelerate science. “The more researchers who engage with the preprint process, the more valuable the server becomes,” Kiessling says.—CELIA ARNAUD
CR E D I T: S CI . ADV.
STRUCTURAL BIOLOGY
