logo
CanyamAI summaries for academic research
language
MobileMobile
  • Phone FeatureWeChat Mini Program
EnglishEnglish
noticeNotice
BlogBlog
delete
arrow
Return

How photosynthetic reaction centers control oxidation power in chlorophyll pairs P680, P700, and P870

delete2006-06-27
delete100
delete
OA
AI
H
Hiroshi Ishikita
W
Wolfram Saenger
J
Jacek Biesiadka
B
Bernhard Loll
E
Ernst‐Walter Knapp *
DOI：10.1073/pnas.0601446103delete
deleteOriginal
deleteShare
deleteSave
View PDF
Abstract

Abstract

En 中文
At the heart of photosynthetic reaction centers (RCs) are pairs of chlorophyll a (Chia), P700 in photosystem I (PSI) and P680 in photosystem II (PSII) of cyanobacteria, algae, or plants, and a pair of bacteriochlorophyll a (BChla), P870 in purple bacterial RCs (PbRCs). These pairs differ greatly in their redox potentials for one-electron oxidation, E,. For P680, E. is 1,100-1,200 mV, but for P700 and P870, Ern is only 500 mV. Calculations with the linearized Poisson-Boltzmann equation reproduce these measured Ern differences successfully. Analyzing the origin for these differences, we found as major factors in PSII the unique Mn4Ca cluster (relative to PSI and PbRC), the position of P680 close to the luminal edge of transmembrane alpha-helix d (relative to PSI), local variations in the cd loop (relative to PbRC), and the intrinsically higher E-m of Chla compared with BChla (relative to PbRC).
Keywords:
electron transfer
photosystem
redox potential
special pair
electrostatic energy
AI Summary

AI Summary

Key information extracted from the uploaded paper, including a brief overview, abstract, background, key highlights, visual analysis, and future outlook.

Journal

P
Proceedings of the National Academy of Sciences of the United States of America
IF:
9.1
Papers:
10.8W
Citations:
73.5W

Organization

No organization information available