Cd2+ Effect on Photosynthetic Apparatus in Synechococcus elongatus and Spinach (Spinacia oleracea L.)

0109751 - UEB-Q 20043093 RIV CZ eng J - Journal Article
Nováková, Marie - Matějová, E. - Sofrová, D.
Cd2+ Effect on Photosynthetic Apparatus in Synechococcus elongatus and Spinach (Spinacia oleracea L.).
[Cd2+ Effect on Photosynthetic Apparatus in Synechococcus elongatus and Spinach (Spinacia oleracea L.).]
Photosynthetica. Roč. 42, č. 3 (2004), s. 425-430. ISSN 0300-3604. E-ISSN 1573-9058
R&D Projects: GA ČR GA525/02/0301
Institutional research plan: CEZ:AV0Z5038910
Keywords : cyanobacteria * heavy metals * photochemical activity
Subject RIV: ED - Physiology
Impact factor: 0.734, year: 2004

Thylakoid membranes (TM) of the cyanobacterium Synechococcus elongatus were exposed for 30 min to the influence of 0, 10, 100, and 1 000 mM CdCl2 (= Cd0, Cd10, Cd100, and Cd1000). Cd10 and Cd100 caused some increase in activity of photosystem 2, PS2 (H2O → DCPIP), while distinct inhibition was observed with Cd1000. We also observed a similar effect when measuring oxygen evolution (H2O → PBQ + FeCy). Chloroplasts of spinach (Spinacia oleracea L.) were incubated for 30 min with 0, 15, 30, and 60 mM CdCl2 (= Cd0, Cd15, Cd30, and Cd60). All concentrations studied inhibited the PS2 activity, the effect being stronger with increasing concentration of Cd2+. The photosynthetic oxygen evolution activity was also influenced most distinctly by the highest concentration employed, i.e. Cd60. Electrophoretic analysis of the protein composition of cyanobacterium TM showed chief changes in the molecular mass regions of Mr 29 000 and 116 000, while with spinach chloroplasts the most distinct differences were observed in the regions of Mr 15 000 and 50 000. Ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBPCO) activity in cyanobacterial spheroplasts still remained on the 40 % level in the case of Cd1000, but it decreased down to approx. 2.5 % in the Cd60 sample of spinach chloroplasts.

Cd2+ Effect on Photosynthetic Apparatus in Synechococcus elongatus and Spinach (Spinacia oleracea L.).
Permanent Link: http://hdl.handle.net/11104/0016859