scholarly journals Water Structural Changes in the L and M Photocycle Intermediates of Bacteriorhodopsin as Revealed by Time-Resolved Step-Scan Fourier Transform Infrared (FTIR) Spectroscopy†

Biochemistry ◽  
2007 ◽  
Vol 46 (10) ◽  
pp. 2787-2796 ◽  
Author(s):  
Joel E. Morgan ◽  
Ahmet S. Vakkasoglu ◽  
Robert B. Gennis ◽  
Akio Maeda
Keyword(s):  
Fourier Transform ◽  
Ftir Spectroscopy ◽  
Structural Changes ◽  
Fourier Transform Infrared ◽  
Time Resolved

Real-Time Pursuit of Crystal Growth by Millisecond Time-Resolved Multichannel Fourier Transform Infrared Spectroscopy

1998 ◽  
Vol 52 (2) ◽  
pp. 222-225
Author(s):  
Mamoru Hashimoto ◽  
Hiro-O Hamaguchi
Keyword(s):  
Fourier Transform ◽  
Infrared Spectroscopy ◽  
Structural Change ◽  
Liquid Phase ◽  
Fourier Transform Infrared Spectroscopy ◽  
Molecular Orientation ◽  
Structural Changes ◽  
Fourier Transform Infrared ◽  
Time Resolved ◽  
Recovery Curves

The surface (about 130 molecular layers) of an oriented thin crystal of decanoic acid was subjected to sudden melting by a laser-induced temperature jump (T-jump), and the process of subsequent crystal re-growth was monitored by millisecond time-resolved multichannel Fourier transform infrared spectroscopy. The gauche–trans structural change of the alkane part of the molecule has been probed by the CH stretch bands in the 2800–3000 cm−1 region. The change in the molecular orientation has been detected by the OH stretch band around 3065 cm−1. The recovery curves for the CH2 antisymmetric stretch and the OH stretch bands are markedly different from each other in the first 200 ms, suggesting that the gauche–trans structural changes precedes the crystal re-growth. After 500 ms, the recovery curves become identical. This result means that the rate of the gauche to the trans structural change is equal to the rate of the recovery of the molecular orientation. It is highly likely that a fast equilibrium is attained between the gauche and the trans conformations in the liquid phase after 500 ms from the sudden melting and that the crystal re-growth takes place solely via the all-trans structure in the liquid phase.

scholarly journals Time-Resolved Fourier Transform Infrared Study on Photoadduct Formation and Secondary Structural Changes within the Phototropin LOV Domain

2009 ◽  
Vol 96 (4) ◽  
pp. 1462-1470 ◽  
Author(s):  
Anna Pfeifer ◽  
Teresa Majerus ◽  
Kazunori Zikihara ◽  
Daisuke Matsuoka ◽  
Satoru Tokutomi ◽  
...  
Keyword(s):  
Fourier Transform ◽  
Structural Changes ◽  
Fourier Transform Infrared ◽  
Lov Domain ◽  
Infrared Study ◽  
Time Resolved

scholarly journals Fourier Transform Infrared Spectroscopy on the Rap·RapGAP Reaction, GTPase Activation without an Arginine Finger

2004 ◽  
Vol 279 (44) ◽  
pp. 46226-46233 ◽  
Author(s):  
Partha P. Chakrabarti ◽  
Yan Suveyzdis ◽  
Alfred Wittinghofer ◽  
Klaus Gerwert
Keyword(s):  
Fourier Transform ◽  
Infrared Spectroscopy ◽  
Fourier Transform Infrared Spectroscopy ◽  
Structural Changes ◽  
Fourier Transform Infrared ◽  
Cleavage Reaction ◽  
Gtp Hydrolysis ◽  
Time Resolved ◽  
Gtpase Activation ◽  
Arginine Finger

GTPaseactivatingproteins (GAPs) down-regulate Ras-like proteins by stimulating their GTP hydrolysis, and a malfunction of this reaction leads to disease formation. In most cases, the molecular mechanism of activation involves stabilization of a catalytic Gln and insertion of a catalytic Arg into the active site by GAP. Rap1 neither possesses a Gln nor does its cognate Rap-GAP employ an Arg. Recently it was proposed that RapGAP provides a catalytic Asn, which substitutes for the Gln found in all other Ras-like proteins (Daumke, O., Weyand, M., Chakrabarti, P. P., Vetter, I. R., and Wittinghofer, A. (2004)Nature429, 197–201). Here, RapGAP-mediated activation has been investigated by time-resolved Fourier transform infrared spectroscopy. Although the intrinsic hydrolysis reactions of Rap and Ras are very similar, the GAP-catalyzed reaction shows unique features. RapGAP binding induces a GTP*conformation in which the three phosphate groups are oriented such that they are vibrationally coupled to each other, in contrast to what was seen in the intrinsic and the Ras·RasGAP reactions. However, the charge shift toward β-phosphate observed with RasGAP was also observed for RapGAP. A GDP·Piintermediate accumulates in the GAP-catalyzed reaction, because the release of Piis eight times slower than the cleavage reaction, and significant GTP synthesis from GDP·Piwas observed. Partial steps of the cleavage reaction are correlated with structural changes of protein side groups and backbone. Thus, the Rap·RapGAP catalytic machinery compensates for the absence of acis-Gln by atrans-Asn and for the catalytic Arg by inducing a different GTP conformation that is more prone to be attacked by a water molecule.

Time-resolved Fourier-transform infrared spectroscopy reveals the hidden bimolecular process of the ferrioxalate actinometer

2019 ◽  
Vol 21 (43) ◽  
pp. 23803-23807 ◽  
Author(s):  
Frank Hendrik Pilz ◽  
Jörg Lindner ◽  
Peter Vöhringer
Keyword(s):  
Fourier Transform ◽  
Infrared Spectroscopy ◽  
Ftir Spectroscopy ◽  
Fourier Transform Infrared Spectroscopy ◽  
Molecular Level ◽  
Fourier Transform Infrared ◽  
Bimolecular Reaction ◽  
Time Resolved

Step-scan FTIR-spectroscopy reveals the bimolecular reaction in the ferrioxalate photochemistry, which builds the molecular-level foundation of the Hatchard–Parker actinometer.

Activation of thermomechanical pulp by laccases as studied by UV-Vis, UV resonance Raman and FTIR spectroscopy 10th EWLP, Stockholm, Sweden, August 25–28, 2008

Holzforschung ◽  
2009 ◽  
Vol 63 (6) ◽  
Author(s):  
Anni Lähdetie ◽  
Tiina Liitiä ◽  
Tarja Tamminen ◽  
Jaakko Pere ◽  
Anna-Stiina Jääskeläinen
Keyword(s):  
Fourier Transform ◽  
Ftir Spectroscopy ◽  
Structural Changes ◽  
Resonance Raman ◽  
Fourier Transform Infrared ◽  
Thermomechanical Pulp ◽  
Trametes Hirsuta ◽  
Melanocarpus Albomyces ◽  
Uv Resonance Raman ◽  
Lignin Structure

Abstract The changes in lignin structure of spruce thermomechanical pulp (TMP), induced by treatment with laccase of Trametes hirsuta (ThL) and laccase of Melanocarpus albomyces (MaL), has been investigated by UV-Vis, UV resonance Raman (UVRR), and Fourier transform infrared (FTIR) spectroscopy. The spectroscopic results showed that the structural changes were small; however, the changes were slightly more pronounced in the case of MaL. Nevertheless, the brightness of the pulps remained higher after treatment with MaL than after treatment with ThL. Accordingly, MaL is a promising enzyme for fiber activation and functionalization.

Time-Resolved Fourier Transform Infrared Study of Structural Changes in the Last Steps of the Photocycles of Glu-204 and Leu-93 Mutants of Bacteriorhodopsin†

Biochemistry ◽  
1997 ◽  
Vol 36 (17) ◽  
pp. 5134-5141 ◽  
Author(s):  
Hideki Kandori ◽  
Yoichi Yamazaki ◽  
Minoru Hatanaka ◽  
Richard Needleman ◽  
Leonid S. Brown ◽  
...  
Keyword(s):  
Fourier Transform ◽  
Structural Changes ◽  
Fourier Transform Infrared ◽  
Infrared Study ◽  
Time Resolved
Sign in / Sign up

Export Citation Format

Share Document