Effect of high hydrostatic pressure on the bacterial mechanosensitive channel MscS

A G Macdonald, B Martinac

    Research output: Contribution to journalArticle

    15 Citations (Scopus)

    Abstract

    We have investigated the effect of high hydrostatic pressure on MscS, the bacterial mechanosensitive channel of small conductance. Pressure affected channel kinetics but not conductance. At negative pipette voltages (corresponding to membrane depolarization in the inside-out patch configuration used in our experiments) the channel exhibited a reversible reduction in activity with increasing hydrostatic pressure between 0 and 900 atm (90 MPa) at 23 degrees C. The reduced activity was characterized by a significant reduction in the channel opening probability resulting from a shortening of the channel openings with increasing pressure. Thus high hydrostatic pressure generally favoured channel closing. Cooling the patch by approximately 10 degrees C, intended to order the bilayer component of the patch by an amount similar to that caused by 50 MPa at 23 degrees C, had relatively little effect. This implies that pressure does not affect channel kinetics via bilayer order. Accordingly we postulate that lateral compression of the bilayer, under high hydrostatic pressure, is responsible. These observations also have implications for our understanding of the adaptation of mechanosensitive channels in deep-sea bacteria.

    Original languageEnglish
    Pages (from-to)434-441
    Number of pages8
    JournalEuropean Biophysics Journal: with Biophysics Letters
    Volume34
    DOIs
    Publication statusPublished - 2005

    Keywords

    • ion channels
    • mechanosensitivity
    • bacteria
    • patch clamp
    • hydrostatic pressure
    • ESCHERICHIA-COLI MSCS
    • ION CHANNELS
    • BIOLOGICAL-MEMBRANES
    • PATCH-CLAMP
    • CELLS
    • MECHANOTRANSDUCTION
    • TRANSDUCTION
    • ADAPTATION
    • LIPOSOMES
    • CURRENTS

    Cite this

    Effect of high hydrostatic pressure on the bacterial mechanosensitive channel MscS. / Macdonald, A G ; Martinac, B .

    In: European Biophysics Journal: with Biophysics Letters, Vol. 34, 2005, p. 434-441.

    Research output: Contribution to journalArticle

    @article{5b0c02cd87ff4b0f8de8655b462c6f59,
    title = "Effect of high hydrostatic pressure on the bacterial mechanosensitive channel MscS",
    abstract = "We have investigated the effect of high hydrostatic pressure on MscS, the bacterial mechanosensitive channel of small conductance. Pressure affected channel kinetics but not conductance. At negative pipette voltages (corresponding to membrane depolarization in the inside-out patch configuration used in our experiments) the channel exhibited a reversible reduction in activity with increasing hydrostatic pressure between 0 and 900 atm (90 MPa) at 23 degrees C. The reduced activity was characterized by a significant reduction in the channel opening probability resulting from a shortening of the channel openings with increasing pressure. Thus high hydrostatic pressure generally favoured channel closing. Cooling the patch by approximately 10 degrees C, intended to order the bilayer component of the patch by an amount similar to that caused by 50 MPa at 23 degrees C, had relatively little effect. This implies that pressure does not affect channel kinetics via bilayer order. Accordingly we postulate that lateral compression of the bilayer, under high hydrostatic pressure, is responsible. These observations also have implications for our understanding of the adaptation of mechanosensitive channels in deep-sea bacteria.",
    keywords = "ion channels, mechanosensitivity, bacteria, patch clamp, hydrostatic pressure, ESCHERICHIA-COLI MSCS, ION CHANNELS, BIOLOGICAL-MEMBRANES, PATCH-CLAMP, CELLS, MECHANOTRANSDUCTION, TRANSDUCTION, ADAPTATION, LIPOSOMES, CURRENTS",
    author = "Macdonald, {A G} and B Martinac",
    year = "2005",
    doi = "10.1007/s00249-005-0478-8",
    language = "English",
    volume = "34",
    pages = "434--441",
    journal = "European Biophysics Journal: with Biophysics Letters",
    issn = "0175-7571",
    publisher = "Springer Verlag",

    }

    TY - JOUR

    T1 - Effect of high hydrostatic pressure on the bacterial mechanosensitive channel MscS

    AU - Macdonald, A G

    AU - Martinac, B

    PY - 2005

    Y1 - 2005

    N2 - We have investigated the effect of high hydrostatic pressure on MscS, the bacterial mechanosensitive channel of small conductance. Pressure affected channel kinetics but not conductance. At negative pipette voltages (corresponding to membrane depolarization in the inside-out patch configuration used in our experiments) the channel exhibited a reversible reduction in activity with increasing hydrostatic pressure between 0 and 900 atm (90 MPa) at 23 degrees C. The reduced activity was characterized by a significant reduction in the channel opening probability resulting from a shortening of the channel openings with increasing pressure. Thus high hydrostatic pressure generally favoured channel closing. Cooling the patch by approximately 10 degrees C, intended to order the bilayer component of the patch by an amount similar to that caused by 50 MPa at 23 degrees C, had relatively little effect. This implies that pressure does not affect channel kinetics via bilayer order. Accordingly we postulate that lateral compression of the bilayer, under high hydrostatic pressure, is responsible. These observations also have implications for our understanding of the adaptation of mechanosensitive channels in deep-sea bacteria.

    AB - We have investigated the effect of high hydrostatic pressure on MscS, the bacterial mechanosensitive channel of small conductance. Pressure affected channel kinetics but not conductance. At negative pipette voltages (corresponding to membrane depolarization in the inside-out patch configuration used in our experiments) the channel exhibited a reversible reduction in activity with increasing hydrostatic pressure between 0 and 900 atm (90 MPa) at 23 degrees C. The reduced activity was characterized by a significant reduction in the channel opening probability resulting from a shortening of the channel openings with increasing pressure. Thus high hydrostatic pressure generally favoured channel closing. Cooling the patch by approximately 10 degrees C, intended to order the bilayer component of the patch by an amount similar to that caused by 50 MPa at 23 degrees C, had relatively little effect. This implies that pressure does not affect channel kinetics via bilayer order. Accordingly we postulate that lateral compression of the bilayer, under high hydrostatic pressure, is responsible. These observations also have implications for our understanding of the adaptation of mechanosensitive channels in deep-sea bacteria.

    KW - ion channels

    KW - mechanosensitivity

    KW - bacteria

    KW - patch clamp

    KW - hydrostatic pressure

    KW - ESCHERICHIA-COLI MSCS

    KW - ION CHANNELS

    KW - BIOLOGICAL-MEMBRANES

    KW - PATCH-CLAMP

    KW - CELLS

    KW - MECHANOTRANSDUCTION

    KW - TRANSDUCTION

    KW - ADAPTATION

    KW - LIPOSOMES

    KW - CURRENTS

    U2 - 10.1007/s00249-005-0478-8

    DO - 10.1007/s00249-005-0478-8

    M3 - Article

    VL - 34

    SP - 434

    EP - 441

    JO - European Biophysics Journal: with Biophysics Letters

    JF - European Biophysics Journal: with Biophysics Letters

    SN - 0175-7571

    ER -