Analysis of pH-induced structural changes of the isolated extrinsic 33 kilodalton protein of photosytem II

Experimental approaches and theoretical modeling were employed to analyzed the pH-induced structural changes of the isolated extrinsic 33 kilodalton protein of photosystem II. Results reveal that 33kDa protein is the only extrinsic protein which exhibits acid-alkaline hysterisis within the 7.0 and 3.8 pH range. Results also show that 33kDa protein consists of two highly conserved secondary structure domains, namely, an alpha-helix and an extended beta-sheet core.