A Herbicide Resistant Euglena Mutant Carrying a Ser to Thr Substitution at Position 265 in the D 1 Protein of Photosystem II
نویسندگان
چکیده
A herbicide resistant Euglena mutant (MSI) has been obtained by adapting wild type cells to increasing concentrations o f D C M U (3-(3',4'-dichlorophenyl)-l ,1-dimethylurea). Lower re sistance levels towards D CM U and metribuzin were observed in MSI when compared with Euglena or C hlam ydom onas mutants with Ser 264 to Ala substitutions. RNA-sequence analysis identified a Ser to Thr change at position 265 (equivalent to position 264 in other organisms), thus making it possible to compare the influence o f amino acids Ser, Ala and Thr at identical positions on the inhibitory effect o f structurally different herbicides in the same species.
منابع مشابه
Mutations in the Subunit of Photosystem II and Resistance to the Phenol Type Herbicide Ioxynil in Synechocystis PCC
Several herbicides block the photosystem II electron transfer because they compete with QB, the second stable electron acceptor o f photosystem II for binding to the D, subunit. We have previously isolated a mutant o f Synechocystis 6714 in which Asn is replaced by Thr at position 266 o f D, (G. Ajlani, I. Meyer, C. Vernotte, and Astier, FEBS Lett. 246, 207 -210 (1989)) and presenting resistanc...
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