Effects of Trypsin and Cations on Chloroplast Membranes
AUTOR(ES)
Jennings, Robert C.
RESUMO
A mild tryptic digestion of chloroplast membranes eliminates the effects of saturating concentrations of cations (3 to 5 millimolar MgCl2) on chlorophyll fluorescence yield, membrane stacking, and photosystem II photochemical efficiency in spinach. At the same time, the negative surface potential of the membranes is increased (by trypsin) as revealed by studies with 9-aminoacridine. High concentrations of cations (25 to 100 millimolar MgCl2) added after trypsin digestion are effective in restoring high fluorescence yields and membrane stacking. High concentrations of cations added after trypsin treatment do not increase the photosystem II efficiency. It is concluded that the “diffuse electrical layer” hypothesis of Barber et al. (Barber J, J Mills, A Love, 1977 FEBS Lett 74: 174-181) satisfactorily explains the effect of trypsin in eliminating the influence of saturating concentrations of cations on chlorophyll fluorescence yield and membrane stacking. However, the effect on photosystem II photochemical efficiency seems to require another mechanism.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=425656Documentos Relacionados
- Oligomycin Effects on ATPase and Photophosphorylation of Pea Chloroplast Thylakoid Membranes 1
- Effects of antibodies, trypsin, and trypsin inhibitors on susceptibility of neonates to rotavirus infection.
- Selective release of excreted DNA sequences from phytohemagglutinin-stimulated human peripheral blood lymphocytes. Effects of trypsin and divalent cations.
- Role of Galactolipids in Spinach Chloroplast Lamellar Membranes: II. Effects of Galactolipid Depletion on Phosphorylation and Electron Flow 12
- EFFECTS OF CATIONS AND ANIONS ON PROTOPLASMIC ELASTICITY1