Open AccessInteraction between photosystem I and ferredoxin
Author(s) -
ZANETTI Giuliana,
MERATI Giuliana
Publication year - 1987
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1111/j.1432-1033.1987.tb13591.x
Subject(s) - ferredoxin , photosystem i , ferredoxin thioredoxin reductase , thylakoid , cytochrome b6f complex , p700 , ferredoxin—nadp(+) reductase , protein subunit , photosystem ii , chemistry , photosystem , biochemistry , electron transport chain , carbodiimide , biophysics , photosynthesis , biology , chloroplast , enzyme , thioredoxin , thioredoxin reductase , gene
Ferredoxin has been effectively cross‐linked to photosystem I complex by treatment of purified particles or thylakoids with N ‐ethyl‐3‐(3‐dimethylaminopropyl)carbodiimide, a zero‐length cross‐linker which stabilizes protein‐protein electrostatic interactions. Analysis of photosystem I polypeptide composition after such a treat‐ment showed a specific decrease of the 20‐kDa subunit and the appearance of a new component of about 42 kDa which was recognized by the anti‐ferredoxin antibody. Cross‐linking of ferredoxin to thylakoids allowed the membrane preparation to photoreduce cytochrome c without requiring exogenous ferredoxin, whereas photosystem I particles purified from treated thylakoids were inactivated in the NADP + photoreduction activity. From these results, it can be inferred that the polypeptide of 20kDa is the photosystem I subunit which interacts with ferredoxin during the photosynthetic electron transport.