Iron components in PS II particles of spinach by Mossbauer spectroscopy

摘要

Mossbauer spectrum measured for the iron components of photosystem II (PS II) particles of spinach is a superposition of 4 doublets. Quadr upole splitting and chemical shifting of doublets I — IV are characteristics of proteins with oxidized cytochrome b-559, reduced cytochrome b-559, Fe~(3+) -Q complex and Fe~(2+) -Q complex respectively. After the PS II particles are treated with La~(3+) , two doublets of Fe~(2+) disappear and Fe~(2+) is converted into Fe~(3+), indicating that'the reduced cytochrome b-559 has been converted into the oxidized cytochrome b-559, and Fe~(2+) -Q complex into Fe~(3+) -Q complex. The Mossbauer spectrum of PS II particles treated with La~(3+) and Ca~(2+) shows that Ca~(2+) can weaken the inhibitory effect of La~(3+) in part, and a portion of the reduced cytochrome b-559 and Fe-Q complex still exist.