Light-dependent inactivation of photosynthetic oxygen evolution during NaCl treatment of photosystem II particles: The role of the 24-kDa protein

✍ Scribed by M. Miyao; N. Murata

• Publisher: Springer
• Year: 1986
• Tongue: English
• Weight: 479 KB
• Volume: 10
• Category: Article
• ISSN: 0166-8595
• DOI: 10.1007/bf00118315

✦ Synopsis

Photosystem (PS) II particles prepared from spinach thylakoids with Triton X-lO0 were treated with 1.5 M NaC1 either in the light or dark. Under both conditions, the 24-kDa and 18-kDa proteins were released from the particles, but rebound to them when the NaCI concentration was reduced to 34 mM by dilution. Oxygen evolution measured after the dilution was inactivated following NaC1 treatment in the light, but not following treatment in the dark. The inactivation in the light was suppressed when 5 mM CaC12 was added during or after the NaC1 treatment. Based on these observations, a scheme is proposed for the mechanism of light-dependent inactivation of oxygen evolution during NaC1 treatment of PS II particles and for the func~tion of the 24-kDa protein in regulating the conformation ~+ of a supposed Ca -binding intrinsic protein.