Association of pharaonis phoborhodopsin with its cognate transducer decreases the photo-dependent reactivity by water-soluble reagents of azide and hydroxylamine

Yuki Sudo, Masayuki Iwamoto, Kazumi Shimono, Naoki Kamo

Research output: Contribution to journalArticle

28 Citations (Scopus)

Abstract

pharaonis phoborhodopsin (ppR; also pharaonis sensory rhodopsin II, psRII) is a receptor of the negative phototaxis of Natronobacterium pharaonis. In halobacterial membrane, ppR forms a complex with its transducer pHtrII, and this complex transmits the light signal to the sensory system in the cytoplasm. In the present work, the truncated transducer, t-Htr, was used which interacts with ppR [Sudo et al. (2001) Photochem. Photobiol. 74, 489-494]. Two water-soluble reagents, hydroxylamine and azide, reacted both with the transducer-free ppR and with the complex ppR/t-Htr (the complex between ppR and its truncated transducer). In the dark, the bleaching rates caused by hydroxylamine were not significantly changed between transducer-free ppR and ppR/t-Htr, or that of the free ppR was a little slower. Illumination accelerated the bleach rates, which is consistent with our previous conclusion that the reaction occurs selectively at the M-intermediate, but the rate of the complex was about 7.4-fold slower than that of the transducer-free ppR. Azide accelerated the M-decay, and its reaction rate of ppR/t-Htr was about 4.6-fold slower than free ppR. These findings suggest that the transducer binding decreases the water accessibility around the chromophore at the M-intermediate. Its implication is discussed.

Original languageEnglish
Pages (from-to)63-69
Number of pages7
JournalBBA - Biomembranes
Volume1558
Issue number1
DOIs
Publication statusPublished - Jan 2 2002
Externally publishedYes

Fingerprint

Hydroxylamine
Azides
Transducers
Water
Natronobacterium
Sensory Rhodopsins
Chromophores
Bleaching
Lighting
Reaction rates
Cytoplasm
Membranes
Light

Keywords

  • Bleach of retinoid protein
  • Flash photolysis
  • Halobacterium salinarum
  • Natronobacterium pharaonis
  • Sensory rhodopsin

ASJC Scopus subject areas

  • Biochemistry
  • Biophysics
  • Cell Biology

Cite this

Association of pharaonis phoborhodopsin with its cognate transducer decreases the photo-dependent reactivity by water-soluble reagents of azide and hydroxylamine. / Sudo, Yuki; Iwamoto, Masayuki; Shimono, Kazumi; Kamo, Naoki.

In: BBA - Biomembranes, Vol. 1558, No. 1, 02.01.2002, p. 63-69.

Research output: Contribution to journalArticle

@article{7f7a9d5d37d94f84935588269eddaad5,
title = "Association of pharaonis phoborhodopsin with its cognate transducer decreases the photo-dependent reactivity by water-soluble reagents of azide and hydroxylamine",
abstract = "pharaonis phoborhodopsin (ppR; also pharaonis sensory rhodopsin II, psRII) is a receptor of the negative phototaxis of Natronobacterium pharaonis. In halobacterial membrane, ppR forms a complex with its transducer pHtrII, and this complex transmits the light signal to the sensory system in the cytoplasm. In the present work, the truncated transducer, t-Htr, was used which interacts with ppR [Sudo et al. (2001) Photochem. Photobiol. 74, 489-494]. Two water-soluble reagents, hydroxylamine and azide, reacted both with the transducer-free ppR and with the complex ppR/t-Htr (the complex between ppR and its truncated transducer). In the dark, the bleaching rates caused by hydroxylamine were not significantly changed between transducer-free ppR and ppR/t-Htr, or that of the free ppR was a little slower. Illumination accelerated the bleach rates, which is consistent with our previous conclusion that the reaction occurs selectively at the M-intermediate, but the rate of the complex was about 7.4-fold slower than that of the transducer-free ppR. Azide accelerated the M-decay, and its reaction rate of ppR/t-Htr was about 4.6-fold slower than free ppR. These findings suggest that the transducer binding decreases the water accessibility around the chromophore at the M-intermediate. Its implication is discussed.",
keywords = "Bleach of retinoid protein, Flash photolysis, Halobacterium salinarum, Natronobacterium pharaonis, Sensory rhodopsin",
author = "Yuki Sudo and Masayuki Iwamoto and Kazumi Shimono and Naoki Kamo",
year = "2002",
month = "1",
day = "2",
doi = "10.1016/S0005-2736(01)00423-0",
language = "English",
volume = "1558",
pages = "63--69",
journal = "Biochimica et Biophysica Acta - Biomembranes",
issn = "0005-2736",
publisher = "Elsevier",
number = "1",

}

TY - JOUR

T1 - Association of pharaonis phoborhodopsin with its cognate transducer decreases the photo-dependent reactivity by water-soluble reagents of azide and hydroxylamine

AU - Sudo, Yuki

AU - Iwamoto, Masayuki

AU - Shimono, Kazumi

AU - Kamo, Naoki

PY - 2002/1/2

Y1 - 2002/1/2

N2 - pharaonis phoborhodopsin (ppR; also pharaonis sensory rhodopsin II, psRII) is a receptor of the negative phototaxis of Natronobacterium pharaonis. In halobacterial membrane, ppR forms a complex with its transducer pHtrII, and this complex transmits the light signal to the sensory system in the cytoplasm. In the present work, the truncated transducer, t-Htr, was used which interacts with ppR [Sudo et al. (2001) Photochem. Photobiol. 74, 489-494]. Two water-soluble reagents, hydroxylamine and azide, reacted both with the transducer-free ppR and with the complex ppR/t-Htr (the complex between ppR and its truncated transducer). In the dark, the bleaching rates caused by hydroxylamine were not significantly changed between transducer-free ppR and ppR/t-Htr, or that of the free ppR was a little slower. Illumination accelerated the bleach rates, which is consistent with our previous conclusion that the reaction occurs selectively at the M-intermediate, but the rate of the complex was about 7.4-fold slower than that of the transducer-free ppR. Azide accelerated the M-decay, and its reaction rate of ppR/t-Htr was about 4.6-fold slower than free ppR. These findings suggest that the transducer binding decreases the water accessibility around the chromophore at the M-intermediate. Its implication is discussed.

AB - pharaonis phoborhodopsin (ppR; also pharaonis sensory rhodopsin II, psRII) is a receptor of the negative phototaxis of Natronobacterium pharaonis. In halobacterial membrane, ppR forms a complex with its transducer pHtrII, and this complex transmits the light signal to the sensory system in the cytoplasm. In the present work, the truncated transducer, t-Htr, was used which interacts with ppR [Sudo et al. (2001) Photochem. Photobiol. 74, 489-494]. Two water-soluble reagents, hydroxylamine and azide, reacted both with the transducer-free ppR and with the complex ppR/t-Htr (the complex between ppR and its truncated transducer). In the dark, the bleaching rates caused by hydroxylamine were not significantly changed between transducer-free ppR and ppR/t-Htr, or that of the free ppR was a little slower. Illumination accelerated the bleach rates, which is consistent with our previous conclusion that the reaction occurs selectively at the M-intermediate, but the rate of the complex was about 7.4-fold slower than that of the transducer-free ppR. Azide accelerated the M-decay, and its reaction rate of ppR/t-Htr was about 4.6-fold slower than free ppR. These findings suggest that the transducer binding decreases the water accessibility around the chromophore at the M-intermediate. Its implication is discussed.

KW - Bleach of retinoid protein

KW - Flash photolysis

KW - Halobacterium salinarum

KW - Natronobacterium pharaonis

KW - Sensory rhodopsin

UR - http://www.scopus.com/inward/record.url?scp=0037005737&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0037005737&partnerID=8YFLogxK

U2 - 10.1016/S0005-2736(01)00423-0

DO - 10.1016/S0005-2736(01)00423-0

M3 - Article

C2 - 11750265

AN - SCOPUS:0037005737

VL - 1558

SP - 63

EP - 69

JO - Biochimica et Biophysica Acta - Biomembranes

JF - Biochimica et Biophysica Acta - Biomembranes

SN - 0005-2736

IS - 1

ER -