4LP8

A Novel Open-State Crystal Structure of the Prokaryotic Inward Rectifier KirBac3.1

Summary for 4LP8

• Entry DOI: 10.2210/pdb4lp8/pdb
• Related: 3ZRS
• Descriptor: Inward rectifier potassium channel Kirbac3.1, DI(HYDROXYETHYL)ETHER, POTASSIUM ION, ... (5 entities in total)
• Functional Keywords: metal transport, potassium channel, membrane
• Biological source: Magnetospirillum magnetotacticum
• Cellular location: Membrane; Multi-pass membrane protein: D9N164
• Total number of polymer chains: 1
• Total formula weight: 34404.22

Authors

Zubcevic, L.,Bavro, V.N.,Muniz, J.R.C.,Schmidt, M.R.,Wang, S.,De Zorzi, R.,Venien-Bryan, C.,Sansom, M.S.P.,Nichols, C.G.,Tucker, S.J. (deposition date: 2013-07-15, release date: 2013-11-20, Last modification date: 2023-09-20)

Primary citation

Zubcevic, L.,Bavro, V.N.,Muniz, J.R.,Schmidt, M.R.,Wang, S.,De Zorzi, R.,Venien-Bryan, C.,Sansom, M.S.,Nichols, C.G.,Tucker, S.J.
Control of KirBac3.1 Potassium Channel Gating at the Interface between Cytoplasmic Domains.
J.Biol.Chem., 289:143-151, 2014

PubMed Abstract: KirBac channels are prokaryotic homologs of mammalian inwardly rectifying potassium (Kir) channels, and recent structures of KirBac3.1 have provided important insights into the structural basis of gating in Kir channels. In this study, we demonstrate that KirBac3.1 channel activity is strongly pH-dependent, and we used x-ray crystallography to determine the structural changes that arise from an activatory mutation (S205L) located in the cytoplasmic domain (CTD). This mutation stabilizes a novel energetically favorable open conformation in which changes at the intersubunit interface in the CTD also alter the electrostatic potential of the inner cytoplasmic cavity. These results provide a structural explanation for the activatory effect of this mutation and provide a greater insight into the role of the CTD in Kir channel gating.

PubMed: 24257749
DOI: 10.1074/jbc.M113.501833

Experimental method

X-RAY DIFFRACTION (2.46 Å)