Evidence map›Paper›PMID 19192202›Full record

ArticlePhotochemistry and photobiology

Infrared monitoring of interlayer water in stacks of purple membranes.

Andrei K Dioumaev, Janos K Lanyi

Open access · greenAbstract read
In one paragraph

Article in Photochemistry and photobiology. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 2 papers.

0numbers the graph read from it
0cells of the map it votes in
2citing papers in PubMed
0.6field-weighted citation impact, top 39% of its field
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

2 citing papers in PubMed, 6 citations in OpenAlex.

  1. Article
  2. Article
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

2 authors at 1 institution in 1 country.

Andrei K DioumaevDepartment of Physiology and Biophysics, University of California Irvine, Irvine, CA, USA. dioumaev@uci.edu
Janos K Lanyi
University of California, Irvine · US

Funding

LIGHT-DRIVEN ION TRANSPORT IN BACTERIAL RHODOPSINSR37GM029498 · NIGMS · UNIVERSITY OF CALIFORNIA-IRVINE · PI LANYI, JANOS K · 2000 to 2009
$4.5M
MECHANISM OF CHLORIDE TRANSPORT BY HALORHODOPSINR01GM029498 · NIGMS · UNIVERSITY OF CALIFORNIA-IRVINE · PI LANYI, JANOS K · 1985 to 2013
$2.1M
NIGMS NIH HHS GM29498NIGMS NIH HHS R01 GM029498NIGMS NIH HHS R37 GM029498
6 · The paper itself

Abstract

The thermodynamic behavior of films of hydrated purple membranes from Halobacterium salinarum and the water confined in it was studied by Fourier transform infrared spectroscopy in the 180-280 K range. Unlike bulk water, water in the thin layers sandwiched between the biological membranes does not freeze at 273 K but will be supercooled to approximately 256 K. The melting point is unaffected, leading to hysteresis between 250 and 273 K. In its heating branch, a gradually increasing light-scattering by ice is observed with rate-limiting kinetics of tens of minutes. Infrared (IR) spectra decomposition provided extinction coefficients for the confined water vibrational bands and their changes upon freezing. Because of the hysteresis, at any given temperature in the 255-270 K range, the interbilayer water could be either liquid or frozen, depending on thermal history. We find that this difference affects the dynamics of the bacteriorhodopsin photocycle in the hysteresis range: the decay of the M and N states and the redistribution between them are different depending on whether or not the water was initially precooled to below the freezing point. However, freezing of interbilayer water does block the M to N transition. Unlike the water, the purple membrane lipids do not undergo any IR-detectable phase transition in the 180-280 K range.

Indexed as

BacteriorhodopsinsHalobacterium salinarumKineticsLipidsPurple MembraneSpectrophotometrySpectrophotometry, InfraredTemperatureThermodynamicsWaterBacteriorhodopsinsLipidsWater

Identifiers

PMID19192202
PMCPMC2710852
OpenAlexW1986604836

What OpenQuestion holds

Textmetadata
LicenceTDM
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.