Changes in photosynthetic electron transfer and state transitions in an herbicide-resistant D1 mutant from soybean cell cultures.

SPIN-LABEL EPR STUDY IN THYLAKOID MEMBRANES FROM A NEW HERBICIDE-RESISTANT D1 MUTANT FROM SOYBEAN CELL CULTURES DEFICIENT IN FATTY ACID DESATURATION. by

Photoautotrophic Chenopodium rubrum Cell Suspension Cultures Resistant against Photosynthesis-Inhibiting Herbicides II. Physiological and Biochemical Properties

Jutta Thiemann and W olfgang Barz Institut für Biochemie und Biotechnologie der Pflanzen, Westfälische Wilhelms-Universität, Hindenburgplatz 55, D-48143 Münster, Bundesrepublik Deutschland Dedicated to Professor Rolf Wiermann on the occasion o f his 60th birthday Z. Naturforsch. 49c, 791-801 (1994); received May 30/July 11, 1994 Chenopodium rubrum, Photoautotrophic Cell Cultures, Herbicide Resi...

Mutations in the D1 Subunit of Photosystem II between Quinone and Herbicide Binding Sites Distinguish

The structure-activity relationships of the plastoquinone Q B binding domain in the D1 subunit of photosystem II (PSII) were investigated by characterization of mutations introduced in the D1 protein. Eight nove1 point mutations in the gene psbA, which encodes D1, were generated in the cyanobacterium Synechocyslis PCC6803 by site-specific mutagenesis in vitro. The effects of the resulting modif...

S1 destabilization and higher sensitivity to light in metribuzin-resistant mutants.

Mutations in the secondary quinone electron acceptor (QB) pocket of the D1 protein conferring a modification on the donor side of photosystem II (PSII) have been characterized by gene cloning and sequencing in two metribuzin-resistant mutants of Synechocystis PCC 6714. The mutations induce different herbicide resistances: in M30, a point mutation at the codon 248, isoleucine to threonine, resul...

Oxygenic photosystem II: the mutation D1-D61N in Synechocystis sp. PCC 6803 retards S-state transitions without affecting electron transfer from YZ to P680+.

Photosynthetic oxygen evolution is powered by photosystem II (PSII), in particular by the oxidized chl a-aggregate P680+, and catalyzed by the oxygen-evolving complex (Mn4X-entity) as well as a tyrosine residue (YZ). The role of particular amino acids as cofactors of electron and proton transfer or as modulators of the activity is still ill-defined. The effects of single-site mutations at the d...