Photoreactions and related charge displacements in the rhodopsin from Sepia officinalis

P. Ormos, A. Dér, Sándor Száraz, Zsolt Tokaji, L. Zimányi, Károly Nagy

Research output: Contribution to journalArticle

3 Citations (Scopus)

Abstract

The photochemical cycle and the accompanying charge displacements of rhodopsin were investigated in membrane fragments and solubilized rhodopsin from the retina of Sepia officinalis. Absorption changes were measured following excitation by a short laser flash. Light excitation produces successive forms with absorption maxima at 536 nm and 474 nm assigned to lumirhodopsin and mesorhodopsin, respectively. The lifetimes of these forms were 8 ± 3 μs and 96 ± 5 μs, respectively. The absorption spectrum of the acid meta form was found to be almost identical to that of rhodopsin. Membrane fragments were also oriented by a d.c. electric field and fixed in gel. Charge displacements following light excitation were measured as a displacement current. The electrical signals from the oriented gels were separated into two exponential components with time constants identical within errors to those obtained from the absorption kinetic experiments. It is shown that the protein conformational changes indicated by the absorption changes are accompanied by intramolecular charge displacements. The transitions are assigned to the decay of the lumi and meso states.

Original languageEnglish
Pages (from-to)7-12
Number of pages6
JournalJournal of Photochemistry and Photobiology, B: Biology
Volume35
Issue number1-2
DOIs
Publication statusPublished - Aug 1996

Fingerprint

Sepia
Sepia officinalis
rhodopsin
Rhodopsin
Gels
Membranes
Absorption spectra
Electric fields
fragments
gels
membranes
excitation
Proteins
Kinetics
Acids
Lasers
retina
Light
time constant
flash

Keywords

  • Absorption kinetics
  • Charge displacement
  • Early receptor potential
  • Rhodopsin

ASJC Scopus subject areas

  • Plant Science
  • Bioengineering
  • Physical and Theoretical Chemistry

Cite this

Photoreactions and related charge displacements in the rhodopsin from Sepia officinalis. / Ormos, P.; Dér, A.; Száraz, Sándor; Tokaji, Zsolt; Zimányi, L.; Nagy, Károly.

In: Journal of Photochemistry and Photobiology, B: Biology, Vol. 35, No. 1-2, 08.1996, p. 7-12.

Research output: Contribution to journalArticle

@article{ffca869f77b8469f8cc42bfbd9a43e78,
title = "Photoreactions and related charge displacements in the rhodopsin from Sepia officinalis",
abstract = "The photochemical cycle and the accompanying charge displacements of rhodopsin were investigated in membrane fragments and solubilized rhodopsin from the retina of Sepia officinalis. Absorption changes were measured following excitation by a short laser flash. Light excitation produces successive forms with absorption maxima at 536 nm and 474 nm assigned to lumirhodopsin and mesorhodopsin, respectively. The lifetimes of these forms were 8 ± 3 μs and 96 ± 5 μs, respectively. The absorption spectrum of the acid meta form was found to be almost identical to that of rhodopsin. Membrane fragments were also oriented by a d.c. electric field and fixed in gel. Charge displacements following light excitation were measured as a displacement current. The electrical signals from the oriented gels were separated into two exponential components with time constants identical within errors to those obtained from the absorption kinetic experiments. It is shown that the protein conformational changes indicated by the absorption changes are accompanied by intramolecular charge displacements. The transitions are assigned to the decay of the lumi and meso states.",
keywords = "Absorption kinetics, Charge displacement, Early receptor potential, Rhodopsin",
author = "P. Ormos and A. D{\'e}r and S{\'a}ndor Sz{\'a}raz and Zsolt Tokaji and L. Zim{\'a}nyi and K{\'a}roly Nagy",
year = "1996",
month = "8",
doi = "10.1016/1011-1344(96)07317-4",
language = "English",
volume = "35",
pages = "7--12",
journal = "Journal of Photochemistry and Photobiology B: Biology",
issn = "1011-1344",
publisher = "Elsevier",
number = "1-2",

}

TY - JOUR

T1 - Photoreactions and related charge displacements in the rhodopsin from Sepia officinalis

AU - Ormos, P.

AU - Dér, A.

AU - Száraz, Sándor

AU - Tokaji, Zsolt

AU - Zimányi, L.

AU - Nagy, Károly

PY - 1996/8

Y1 - 1996/8

N2 - The photochemical cycle and the accompanying charge displacements of rhodopsin were investigated in membrane fragments and solubilized rhodopsin from the retina of Sepia officinalis. Absorption changes were measured following excitation by a short laser flash. Light excitation produces successive forms with absorption maxima at 536 nm and 474 nm assigned to lumirhodopsin and mesorhodopsin, respectively. The lifetimes of these forms were 8 ± 3 μs and 96 ± 5 μs, respectively. The absorption spectrum of the acid meta form was found to be almost identical to that of rhodopsin. Membrane fragments were also oriented by a d.c. electric field and fixed in gel. Charge displacements following light excitation were measured as a displacement current. The electrical signals from the oriented gels were separated into two exponential components with time constants identical within errors to those obtained from the absorption kinetic experiments. It is shown that the protein conformational changes indicated by the absorption changes are accompanied by intramolecular charge displacements. The transitions are assigned to the decay of the lumi and meso states.

AB - The photochemical cycle and the accompanying charge displacements of rhodopsin were investigated in membrane fragments and solubilized rhodopsin from the retina of Sepia officinalis. Absorption changes were measured following excitation by a short laser flash. Light excitation produces successive forms with absorption maxima at 536 nm and 474 nm assigned to lumirhodopsin and mesorhodopsin, respectively. The lifetimes of these forms were 8 ± 3 μs and 96 ± 5 μs, respectively. The absorption spectrum of the acid meta form was found to be almost identical to that of rhodopsin. Membrane fragments were also oriented by a d.c. electric field and fixed in gel. Charge displacements following light excitation were measured as a displacement current. The electrical signals from the oriented gels were separated into two exponential components with time constants identical within errors to those obtained from the absorption kinetic experiments. It is shown that the protein conformational changes indicated by the absorption changes are accompanied by intramolecular charge displacements. The transitions are assigned to the decay of the lumi and meso states.

KW - Absorption kinetics

KW - Charge displacement

KW - Early receptor potential

KW - Rhodopsin

UR - http://www.scopus.com/inward/record.url?scp=0030220321&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0030220321&partnerID=8YFLogxK

U2 - 10.1016/1011-1344(96)07317-4

DO - 10.1016/1011-1344(96)07317-4

M3 - Article

AN - SCOPUS:0030220321

VL - 35

SP - 7

EP - 12

JO - Journal of Photochemistry and Photobiology B: Biology

JF - Journal of Photochemistry and Photobiology B: Biology

SN - 1011-1344

IS - 1-2

ER -