@article{25432b18c5724bae9028375a21995c12,
title = "Structural and mechanistic characterization of an archaeal-like chaperonin from a thermophilic bacterium",
abstract = "The chaperonins (CPNs) are megadalton sized hollow complexes with two cavities that open and close to encapsulate non-native proteins. CPNs are assigned to two sequence-related groups that have distinct allosteric mechanisms. In Group I CPNs a detachable co-chaperone, GroES, closes the chambers whereas in Group II a built-in lid closes the chambers. Group I CPNs have a bacterial ancestry, whereas Group II CPNs are archaeal in origin. Here we describe open and closed crystal structures representing a new phylogenetic branch of CPNs. These Group III CPNs are divergent in sequence and structure from extant CPNs, but are closed by a built-in lid like Group II CPNs. A nucleotide-sensing loop, present in both Group I and Group II CPNs, is notably absent. We identified inter-ring pivot joints that articulate during ring closure. These Group III CPNs likely represent a relic from the ancestral CPN that formed distinct bacterial and archaeal branches.",
author = "An, {Young Jun} and Rowland, {Sara E.} and Na, {Jung Hyun} and Dario Spigolon and Hong, {Seung Kon} and Yoon, {Yeo Joon} and Lee, {Jung Hyun} and Robb, {Frank T.} and Cha, {Sun Shin}",
note = "Funding Information: We thank the beamline staffs at PLS and PF for support with the data collection. F.T.R., D.S. and S.E.R. acknowledge the kind collaboration and insightful discussions with Dr. Zvi Kelman and his staff at the BL2 Laboratory, National Institutes of Science and Technology, USA. This work was supported by National Research Foundation of Korea grants (NRF-2015R1A2A2A01004168, NRF-2015M1A5A1037480, and NRF-2016R1A2A1A05005078), a grant from the Collaborative Genome Program (20140428) funded by the Ministry of Oceans and Fisheries, Korea, and NSF USA grants EAR0747394, EAR0747412, C-DEBI and MCB0605301 (F.T.R.) and the project {\textquoteleft}Development of biomedical materials based on marine proteins{\textquoteright}, funded by the Ministry of Oceans and Fisheries, Korea (J.-H.L.). Publisher Copyright: {\textcopyright} 2017 The Author(s).",
year = "2017",
month = dec,
day = "1",
doi = "10.1038/s41467-017-00980-z",
language = "English",
volume = "8",
journal = "Nature Communications",
issn = "2041-1723",
publisher = "Nature Publishing Group",
number = "1",
}