| 1 | Author
| R. Fromme, G. Renger | Requires cookie* | | Title
| Studies on Herbicide Binding in Photosystem II Membrane Fragments from Spinach  | | | Abstract
| The mechanism of atrazine binding and its modification by Chelex-100-induced Ca2+ deple tion and proteolytic degradation by trypsin, was analyzed in PS II membrane fragments from spinach. It was found: 1) Chelex-100 treatment leads in a comparatively slow process (/, 2 = 5 — 10 min) to Ca2+ re moval from a site that is characterized by a high affinity as reflected by K u values of the order of 10 7 M. The number of these binding sites was found to be almost one per PS II in samples washed twice with Ca2+ -free buffer. 2) Chelex-100 treatment does not affect the affinity of atrazine binding but increases the susceptibility to proteolytic attack by trypsin. 3) The electron transport activity is only slightly affected by Chelex-100 treatment. 4) The atrazine binding exhibits a rather small T-dependence within the physiological range of 7 °C to 27 °C. The implications of these findings for herbicide binding are discussed. | | |
Reference
| Z. Naturforsch. 45c, 373—378 (1990); received November 15 1989 | | |
Published
| 1990 | | |
Keywords
| Atrazine Binding, Photosystem II, Ca2+ Effects, Temperature Dependence, Mild Proteolysis | | |
Similar Items
| Find | | DEBUG INFO
| | | | TEI-XML for
| default:Reihe_C/45/ZNC-1990-45c-0373.pdf | | | Identifier
| ZNC-1990-45c-0373 | | | Volume
| 45 | |
|