Voltage-gated proton channel

Voltage-gated proton channel

Voltage-gated proton channels are ion channels that have the unique property of opening with depolarization, but in a strongly pH-sensitive manner [Citation
last1=Cherny
first1=V.V.
last2=Markin
first2=V.S.
last3=DeCoursey
first3=T.E.
publication-date=1995-06
title=The voltage-activated hydrogen ion conductance in rat alveolar epithelial cells is determined by the pH gradient
periodical=Journal of General Physiology
volume=105
issue=6
pages=861-896
url=http://www.jgp.org/cgi/reprint/105/6/861.pdf
issn=0022-1295
accessdate=2008-07-14] . The result is that these channels open only when the electrochemical gradient is outward, such that their opening will only allow protons to leave cells. Their function thus appears to be acid extrusion from cells [Citation
last=DeCoursey
first=T.E.
publication-date=2003
title=Voltage-gated proton channels and other proton transfer pathways
periodical=Physiological Reviews
volume=83
issue=2
pages=475-579
url=http://physrev.physiology.org/cgi/content/full/83/2/475
issn=0031-9333
doi=10.1152/physrev.00028.2002
oclc=205658168
accessdate=2008-07-14] .

Another important function occurs in phagocytes (e.g. eosinophils, neutrophils, and macrophages) during the respiratory burst. When bacteria or other microbes are engulfed by phagocytes, the enzyme NADPH oxidase assembles in the membrane and begins to produce reactive oxygen species (ROS) that help kill bacteria [Citation
last=Babior
first=B.M.
author-link=Bernard Babior
publication-date=
date=1999-03-01
title=NADPH Oxidase: An Update.
periodical=Blood
volume=93
issue=5
pages=1464-1476
url=http://bloodjournal.hematologylibrary.org/cgi/reprint/93/5/1464.pdf
issn=1528-0020
accessdate=2008-07-14] . NADPH oxidase is electrogenic [Citation
last1=Henderson
first1=L.M.
last2=Chappell
first2=J.B.
last3=Jones
first3=O.T.G.
publication-date=1987-09-01
title=The superoxide-generating NADPH oxidase of human neutrophils is electrogenic and associated with an H+ channel
periodical=The Biochemical Journal
volume=246
issue=2
pages=325-329
url=http://www.biochemj.org/bj/246/0325/2460325.pdf
issn=0264-6021
oclc=116254550
accessdate=2008-07-14] , moving electrons across the membrane, and proton channels open to allow proton flux to balance the electron movement electrically [Citation
last1=Murphy
first1=R.
last2=DeCoursey
first2=T.E.
publication-date=2006-08-08
title=Charge compensation during the phagocyte respiratory burst
periodical=Biochimica et Biophysica Acta
series=Bioenergetics
volume =1757
issue=8
pages=996-1011
url=http://dx.doi.org/10.1016/j.bbabio.2006.01.005
issn=0005-2728
doi=10.1016/j.bbabio.2006.01.005
accessdate=2008-07-14] .

References


Wikimedia Foundation. 2010.

Игры ⚽ Поможем написать реферат

Look at other dictionaries:

  • Voltage-gated potassium channel — Ion channel (eukariotic) Potassium channel, structure in a membrane like environment. Calculated hydrocarbon boundaries of the lipid bilayer are indicated by red and blue dots. Identifiers Symbol Ion trans …   Wikipedia

  • Proton channel — Proton channels are ion channels for protons. Most prominent are the voltage gated proton channels …   Wikipedia

  • Voltage-dependent calcium channel — Voltage dependent calcium channels (VDCC) are a group of voltage gated ion channels found in excitable cells (e.g., muscle, glial cells, neurons, etc.) with a permeability to the ion Ca2+.[1][2] These channels are slightly permeable to sodium… …   Wikipedia

  • Ligand-gated ion channel — Neurotransmitter gated ion channel transmembrane region Ligand gated ion channel Identifiers Symbol Neur chan memb Pfam …   Wikipedia

  • Cyclic nucleotide-gated ion channel — Cyclic nucleotide gated (CNG) ion channels are ion channels that function in response to the binding of cyclic nucleotides. CNG channels are nonselective cation channels that are found in the membranes of various types of cells. Signal… …   Wikipedia

  • Ion channel — Not to be confused with: Ion Television or Ion implantation. Schematic diagram of an ion channel. 1 channel domains (typically four per channel), 2 outer vestibule, 3 selectivity filter, 4 diameter of selectivity filter, 5 phosphorylation site, 6 …   Wikipedia

  • Sodium channel — Sodium channels are integral membrane proteins that form ion channels, conducting sodium ions (Na+) through a cell s plasma membrane.[1][2] They are classified according to the trigger that opens the channel for such ions, i.e. either a voltage… …   Wikipedia

  • N-type calcium channel — Calcium channel, voltage dependent, N type, alpha 1B subunit Identifiers Symbols CACNA1B; BIII; CACNL1A5; CACNN; Cav2.2 External IDs …   Wikipedia

  • Potassium channel — Top view of potassium ions (purple) moving through potassium channel (PDB 1BL8) In the field of cell biology, potassium channels are the most widely distributed type of ion channel and are found in virtually all living organisms …   Wikipedia

  • BK channel — KCNMA1 The domain structure of BK channels Identifiers Symbol KCNMA1 Alt. symbols SLO …   Wikipedia

Share the article and excerpts

Direct link
… Do a right-click on the link above
and select “Copy Link”