Effect of plastocyanin and phycocyanin on the photosensitivity of chlorophyll-containing bilayer membranes

Abstract

Photovoltaic effects were studied in bilayer membranes constructed from phosphatidyl choline, monogalactosyl diglyceride, chlorophyll alpha and beta-carotene. It was demonstrated that the biliprotein C-phycocyanin enhanced the photosensitivity of these membranes. Plastocyanin, an important photosynthetic electron transfer protein, was also found to be effective in enhancing the membrane photovoltage. The C-phycocyanin and plastocyanin were effective on opposite sides of the membrane. Plastocyanin operates to transfer electrons into the membrane, while C-phycocyanin directs electron transfer from the membrane. Membranes containing monogalactosyl diglyceride were found to be extremely stable and were most susceptible to enhancement of photosensitivity by introduction of the proteins. The plastocyanin and C-phycocyanin when used together appeared to operate synergistically.

Screening of cyanobacteria and microalgae for their ability to synthesize silver nanoparticles with antibacterial activity

“…C-phycocyanin is part of phycobilisomes; structures attached to thylakoids involved in light harvesting and transferring electrons toward photosystem II reaction centers [28]. It has been shown that C-phycocyanin directs an electron transfer in an experimental set up [8] and that it binds to heavy metals [14]; however to our knowledge there are no data on whether an in vitro electron transfer from C-phycocyanin to Ag ion is possible. It has been reported that when a red pigment R-phycoerythrin was used, Ag-NPs were formed without the need for a reductant [4].…”

<p>Cyanobacteria – A Promising Platform in Green Nanotechnology: A Review on Nanoparticles Fabrication and Their Prospective Applications</p>

“…78 , 79 It has been shown that C-phycocyanin controls electron transfer and has the ability to bind to heavy metals. 80 , 81 Recent studies have demonstrated the role of C-phycocyanin in fabrication of NPs; Pate et al showed that utilizing C-phycocyanin extracted from two different cyanobacteria species ( Spirulina and Limnothrix species) resulted in production of Ag-NPs with different shapes and sizes. 55 The authors attributed these differences in morphological features to the fact that the two C-phycocyanin preparations differed in purity and molecular weight.…”

A Quantitative Comparison of Chlorophyll Bilayers Formed With and Without Solvent

“…Studies of photoeffects in chlorophyll (chl) containing bilayers are useful for probing photoprocesses that occur in photosynthesis, as well as for exploring the possible applications for conversion of solar energy (Berns, 1976;Tien, 1976;Hong, 1976). Recent studies have centered around means by which to increase the quantum efficiency of pigmented bilayers (Masters and Mauzerall, 1978;Chen and Berns, 1979). The Mueller-Rudin [MR] method for bilayer formation used in these studies requires the presence of solvent (Mueller ef al., 1962).…”