In:
Proceedings of the National Academy of Sciences, Proceedings of the National Academy of Sciences, Vol. 97, No. 25 ( 2000-12-05), p. 13561-13566
Abstract:
The reaction center (RC) of photosynthetic bacteria is a membrane
protein complex that promotes a light-induced charge separation during the primary process of photosynthesis. In the photosynthetic electron
transfer chain, the soluble electron carrier proteins transport electrons to the RC and reduce the photo-oxidized special-pair of
bacteriochlorophyll. The high-potential iron-sulfur protein (HiPIP) is known to serve as an electron donor to the RC in some species, where
the c -type cytochrome subunit, the peripheral subunit of
the RC, directly accepts electrons from the HiPIP. Here we report the crystal structures of the RC and the HiPIP from Thermochromatium ( Tch. ) tepidum , at 2.2-Å and 1.5-Å resolution, respectively. Tch. tepidum can grow at the highest temperature of all
known purple bacteria, and the Tch. tepidum RC shows
some degree of stability to high temperature. Comparison with the RCs of mesophiles, such as Blastochloris viridis , has shown
that the Tch. tepidum RC possesses more Arg residues at
the membrane surface, which might contribute to the stability of this membrane protein. The RC and the HiPIP both possess hydrophobic patches
on their respective surfaces, and the HiPIP is expected to interact with the cytochrome subunit by hydrophobic interactions near the
heme-1, the most distal heme to the special-pair.
Type of Medium:
Online Resource
ISSN:
0027-8424
,
1091-6490
DOI:
10.1073/pnas.240224997
Language:
English
Publisher:
Proceedings of the National Academy of Sciences
Publication Date:
2000
detail.hit.zdb_id:
209104-5
detail.hit.zdb_id:
1461794-8
SSG:
11
SSG:
12
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