Figure - PMC

Skip to main content

An official website of the United States government

Here's how you know

Here's how you know

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.

View full-text article in PMC

. 2010 Apr 20;10(4):4010–4039. doi: 10.3390/s100404010

Search in PMC
Search in PubMed
View in NLM Catalog
Add to search

© 2010 by the authors; licensee MDPI, Basel, Switzerland.

This article is an open-access article distributed under the terms and conditions of the Creative Commons Attribution license (http://creativecommons.org/licenses/by/3.0/).

PMC Copyright notice

Figure 4. — (A) Detail of the SRII-HtrII X-ray structure, which focuses on the midmembrane SRII-HtrII interface containing the core signal relay structure. SRII and HtrII are colored orange and blue, respectively. The numbers in the smaller font are the length between the respective amino acid residues. Using FTIR spectroscopy and photochemical techniques, we and another group reported that Thr199^SRII forms a hydrogen bond with Asn74^HtrII [56,79]. A functionally important residue, Thr204^SRII, forms a hydrogen bond with Tyr174^SRII. Tyr174^SRII is also essential for the phototaxis function [81]. (B) The structural change of the retinal chromophore upon formation of the K intermediate of SRII. All seven monodeuterated all-trans retinal analogues were synthesized, and the FTIR spectra were measured at 77 K. The enhanced C₁₄-D stretch in the K intermediate was assigned as the band originating from the local steric constraint between C₁₄-D and Thr204^SRII [75,80]. We reported that the band intensity correlated well with the phototaxis signaling efficiency, indicating its functional importance [80].