| Autor: |
Wolber, Paul K., Steinback, Katherine E. |
| Zdroj: |
Zeitschrift für Naturforschung C; May 1984, Vol. 39 Issue: 5 p425-429, 5p |
| Abstrakt: |
Spinach thylakoids have been photoaffinity labeled with [14C]azidoatrazine in vitro and with specific [3H]amino acids in vivo. The radiolabeled protein has been isolated, cleaved with trypsin, and the resulting fragments have been identified by their characteristic [3H]amino acid incorporation. The peptide pattern has been interpreted using the known gene sequence for the QB-protein of spinach thylakoids, which is the major protein labeled by both the in vivo and in vitro procedures. When analyzed by gel filtration, over 80% of the 14C-activity migrated as two peaks: one as undigested protein at the void volume and the other at an apparent MW of 8.35 ± 0.76 kilodaltons. The remaining activity migrated with the included volume as free azidoatrazine. Fragments were analysed for covalent [14C]azidoatrazine binding; the tryptic peptide covalently labeled by [14C]azidoatrazine was found to be the fragment Pro-141 to Arg-225. This peptide is well removed from the site of a single amino acid change at Ser-264 implicated in triazine resistance, but includes a region suggested to be involved in Qв-binding by homology with sequences of two reaction center proteins from Rhodopseudomonas capsulata. |
| Databáze: |
Supplemental Index |
| Externí odkaz: |
|
