Effects of copper on photopigments and photosystem ii activity of cyanophage n‐1 resistant mutant

Abstract

The spheroplasts of cyanophage N‐1 resistant mutant have been used to examine the effects of Cu²⁺ on photopigments and photosystem II. Chlorophyll‐α, carotenoid and protein content were appreciably reduced by this metal. Photosystem II activity was inhibited by 50% at a Cu²⁺ concentration of 10 umol L^‐1 and was completely blocked at 50 umol L^‐1 Cu²⁺. Diphenyl carbazide did not protect the system from Cu²⁺ inhibition. However, the presence of EDTA reduced the inhibitory effects.

Keywords:

• Photopigments
• photosystem II
• Nostoc muscorum
• cyanophage N‐1
• spheroplast