Purification and molecular properties of 3 polypeptides released from a highly active O2‐evolving photosystem‐II preparation by Tris‐treatment

[摘要]

Tris-treatment of a highly active O₂-evolving photosystem-II preparation induced release of 3 polypeptides (M _r 33 000, 24 000 and 18 000), concomitant with inhibition of O₂ evolution [FEBS Lett. (1981)_133. 265-268]. The 3 polypeptides were purified with the use of electrofocusing. Isoelectric points of the proteins were 5.1, 6.5 and 9.2 in order of decreasing M _r value. Only a trace amount of histidine, cystein and methionine were detected in these proteins. Based on the amino acid compositions, polarity indexes of the proteins were calculated to be 47–49%, suggesting the 3 proteins to be hydrophilic.

[学科分类] 生物化学/生物物理

[关键词] O2 evolution;Membrane protein;Photosystem II;Chloroplast Photosynthesis;PS;photosystem;Tris;tris(hydroxymethyl)aminomethane;Mes;2-(N-morpholino)-ethane- sulphonic acid;SDS;sodium dodecyl sulfate;PAGE;polyacrylamide gel electrohporesis;A 280;absorbance at 280 nm;pI;isoelectric point;TMBZ;3;3′;5;5′-tetra-methylbenzidine;CF1;chloroplast coupling factor 1;atrazine;2-chloro-4-ethylamino-6-isopropylamino-s-triazine