Structure and molecular mechanism of an anion-selective mechanosensitive channel of small conductance

Xiaozhe Zhang, Jingjing Wang, Yue Feng, Jingpeng Ge, Wenfei Li, Wending Sun, Irene Iscla, Jie Yu, Paul Blount, Yang Li, Maojun Yang

Research output: Contribution to journalArticle

35 Citations (Scopus)

Abstract

Mechanosensitive (MS) channels are universal cellular membrane pores. Bacterial MS channels, as typified by MS channel of small conductance (MscS) from Escherichia coli (EcMscS), release osmolytes under hypoosmotic conditions. MS channels are known to be ion selective to different extents, but the underlying mechanism remains poorly understood. Here we identify an anion-selective MscS channel from Thermoanaerobacter tengcongensis (TtMscS). The structure of TtMscS closely resembles that of EcMscS, but it lacks the large cytoplasmic equatorial portals found in EcMscS. In contrast, the cytoplasmic pore formed by the C-terminal β-barrel of TtMscS is larger than that of EcMscS and has a strikingly different pattern of electrostatic surface potential. Swapping the β-barrel region between TtMscS and EcMscS partially switches the ion selectivity. Our study defines the role of the β-barrel in the ion selection of an anion-selective MscS channel and provides a structural basis for understanding the ion selectivity of MscS channels.

Original languageEnglish (US)
Pages (from-to)18180-18185
Number of pages6
JournalProceedings of the National Academy of Sciences of the United States of America
Volume109
Issue number44
DOIs
StatePublished - Oct 30 2012

Fingerprint

Molecular Structure
Anions
Ions
Thermoanaerobacter
Static Electricity
Escherichia coli
Membranes

Keywords

  • Anion selection
  • Crystal structure
  • Cytoplasmic region
  • Electrophysiology
  • Single channel recording

ASJC Scopus subject areas

  • General

Cite this

Structure and molecular mechanism of an anion-selective mechanosensitive channel of small conductance. / Zhang, Xiaozhe; Wang, Jingjing; Feng, Yue; Ge, Jingpeng; Li, Wenfei; Sun, Wending; Iscla, Irene; Yu, Jie; Blount, Paul; Li, Yang; Yang, Maojun.

In: Proceedings of the National Academy of Sciences of the United States of America, Vol. 109, No. 44, 30.10.2012, p. 18180-18185.

Research output: Contribution to journalArticle

Zhang, Xiaozhe ; Wang, Jingjing ; Feng, Yue ; Ge, Jingpeng ; Li, Wenfei ; Sun, Wending ; Iscla, Irene ; Yu, Jie ; Blount, Paul ; Li, Yang ; Yang, Maojun. / Structure and molecular mechanism of an anion-selective mechanosensitive channel of small conductance. In: Proceedings of the National Academy of Sciences of the United States of America. 2012 ; Vol. 109, No. 44. pp. 18180-18185.
@article{6d6e6aa6a171458087297fa1f944930e,
title = "Structure and molecular mechanism of an anion-selective mechanosensitive channel of small conductance",
abstract = "Mechanosensitive (MS) channels are universal cellular membrane pores. Bacterial MS channels, as typified by MS channel of small conductance (MscS) from Escherichia coli (EcMscS), release osmolytes under hypoosmotic conditions. MS channels are known to be ion selective to different extents, but the underlying mechanism remains poorly understood. Here we identify an anion-selective MscS channel from Thermoanaerobacter tengcongensis (TtMscS). The structure of TtMscS closely resembles that of EcMscS, but it lacks the large cytoplasmic equatorial portals found in EcMscS. In contrast, the cytoplasmic pore formed by the C-terminal β-barrel of TtMscS is larger than that of EcMscS and has a strikingly different pattern of electrostatic surface potential. Swapping the β-barrel region between TtMscS and EcMscS partially switches the ion selectivity. Our study defines the role of the β-barrel in the ion selection of an anion-selective MscS channel and provides a structural basis for understanding the ion selectivity of MscS channels.",
keywords = "Anion selection, Crystal structure, Cytoplasmic region, Electrophysiology, Single channel recording",
author = "Xiaozhe Zhang and Jingjing Wang and Yue Feng and Jingpeng Ge and Wenfei Li and Wending Sun and Irene Iscla and Jie Yu and Paul Blount and Yang Li and Maojun Yang",
year = "2012",
month = "10",
day = "30",
doi = "10.1073/pnas.1207977109",
language = "English (US)",
volume = "109",
pages = "18180--18185",
journal = "Proceedings of the National Academy of Sciences of the United States of America",
issn = "0027-8424",
number = "44",

}

TY - JOUR

T1 - Structure and molecular mechanism of an anion-selective mechanosensitive channel of small conductance

AU - Zhang, Xiaozhe

AU - Wang, Jingjing

AU - Feng, Yue

AU - Ge, Jingpeng

AU - Li, Wenfei

AU - Sun, Wending

AU - Iscla, Irene

AU - Yu, Jie

AU - Blount, Paul

AU - Li, Yang

AU - Yang, Maojun

PY - 2012/10/30

Y1 - 2012/10/30

N2 - Mechanosensitive (MS) channels are universal cellular membrane pores. Bacterial MS channels, as typified by MS channel of small conductance (MscS) from Escherichia coli (EcMscS), release osmolytes under hypoosmotic conditions. MS channels are known to be ion selective to different extents, but the underlying mechanism remains poorly understood. Here we identify an anion-selective MscS channel from Thermoanaerobacter tengcongensis (TtMscS). The structure of TtMscS closely resembles that of EcMscS, but it lacks the large cytoplasmic equatorial portals found in EcMscS. In contrast, the cytoplasmic pore formed by the C-terminal β-barrel of TtMscS is larger than that of EcMscS and has a strikingly different pattern of electrostatic surface potential. Swapping the β-barrel region between TtMscS and EcMscS partially switches the ion selectivity. Our study defines the role of the β-barrel in the ion selection of an anion-selective MscS channel and provides a structural basis for understanding the ion selectivity of MscS channels.

AB - Mechanosensitive (MS) channels are universal cellular membrane pores. Bacterial MS channels, as typified by MS channel of small conductance (MscS) from Escherichia coli (EcMscS), release osmolytes under hypoosmotic conditions. MS channels are known to be ion selective to different extents, but the underlying mechanism remains poorly understood. Here we identify an anion-selective MscS channel from Thermoanaerobacter tengcongensis (TtMscS). The structure of TtMscS closely resembles that of EcMscS, but it lacks the large cytoplasmic equatorial portals found in EcMscS. In contrast, the cytoplasmic pore formed by the C-terminal β-barrel of TtMscS is larger than that of EcMscS and has a strikingly different pattern of electrostatic surface potential. Swapping the β-barrel region between TtMscS and EcMscS partially switches the ion selectivity. Our study defines the role of the β-barrel in the ion selection of an anion-selective MscS channel and provides a structural basis for understanding the ion selectivity of MscS channels.

KW - Anion selection

KW - Crystal structure

KW - Cytoplasmic region

KW - Electrophysiology

KW - Single channel recording

UR - http://www.scopus.com/inward/record.url?scp=84868120537&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84868120537&partnerID=8YFLogxK

U2 - 10.1073/pnas.1207977109

DO - 10.1073/pnas.1207977109

M3 - Article

C2 - 23074248

AN - SCOPUS:84868120537

VL - 109

SP - 18180

EP - 18185

JO - Proceedings of the National Academy of Sciences of the United States of America

JF - Proceedings of the National Academy of Sciences of the United States of America

SN - 0027-8424

IS - 44

ER -