PDBsum entry 6nq9

Membrane protein

PDB id: 6nq9

Contents

Protein chains

208 a.a.

PDB id:

6nq9

Name:

Membrane protein

Title:

Crystal structure of yetj mutant from bacillus subtilis - d195e

Structure:

Uncharacterized protein yetj. Chain: a, b, c, d. Engineered: yes. Mutation: yes

Source:

Bacillus subtilis (strain 168). Organism_taxid: 224308. Strain: 168. Gene: yetj, bsu07200. Expressed in: escherichia coli 'bl21-gold(de3)plyss ag'. Expression_system_taxid: 866768

Resolution:

3.10Å R-factor: 0.249 R-free: 0.276

Authors:

G.Guo,Y.Chang,Q.Liu

Key ref:

G.Guo et al. (2019). Ion and pH Sensitivity of a TMBIM Ca²⁺ Channel. Structure, 27, 1013. PubMed id: 30930064 DOI: 10.1016/j.str.2019.03.003

Date:

19-Jan-19 Release date: 17-Apr-19

Protein chains

O31539  (YETJ_BACSU) -  Uncharacterized protein YetJ from Bacillus subtilis (strain 168)

Seq: 214 a.a.

Struc: 208 a.a.*

* PDB and UniProt seqs differ at 1 residue position (black cross)

DOI no: 10.1016/j.str.2019.03.003

Structure 27:1013 (2019)

PubMed id: 30930064

Ion and pH Sensitivity of a TMBIM Ca²⁺ Channel.

G.Guo, M.Xu, Y.Chang, T.Luyten, B.Seitaj, W.Liu, P.Zhu, G.Bultynck, L.Shi, M.Quick, Q.Liu.

ABSTRACT

The anti-apoptotic transmembrane Bax inhibitor motif (TMBIM) containing protein family regulates Ca²⁺ homeostasis, cell death, and the progression of diseases including cancers. The recent crystal structures of the TMBIM homolog BsYetJ reveal a conserved Asp171-Asp195 dyad that is proposed in regulating a pH-dependent Ca²⁺ translocation. Here we show that BsYetJ mediates Ca²⁺ fluxes in permeabilized mammalian cells, and its interaction with Ca²⁺ is sensitive to protons and other cations. We report crystal structures of BsYetJ in additional states, revealing the flexibility of the dyad in a closed state and a pore-opening mechanism. Functional studies show that the dyad is responsible for both Ca²⁺ affinity and pH dependence. Computational simulations suggest that protonation of Asp171 weakens its interaction with Arg60, leading to an open state. Our integrated analysis provides insights into the regulation of the BsYetJ Ca²⁺ channel that may inform understanding of human TMBIM proteins regarding their roles in cell death and diseases.