Differential sensitivity of bicarbonate-reversible formate effects on herbicide-resistant mutants of Synechocystis 6714.
نویسندگان
چکیده
Herbicide-resistant mutants of the cyanobacterium Synechocystis 6714, that are altered in specific amino acids in their D-1 protein, shows differential sensitivity to formate treatment. Measurements on oxygen yield in a sequence of flashes, chlorophyll (Chl) a fluorescence transients and Chl a fluorescence yield decay after a flash reveal that the resistance of cells to formate treatment is in the following (highest to lowest) order: [double mutant] A251V/F211S (Az V) greater than [single mutant] F211S (Az I) congruent to wild type greater than [single mutant] S264A (DCMU II-A). Significance of these results in terms of overlapping between the herbicide and bicarbonate binding niches on the D-1 protein is discussed.
منابع مشابه
Differential effects of formate in single and double mutants of D 1 in Synechocystis sp . PCC 6714
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ورودعنوان ژورنال:
- FEBS letters
دوره 267 2 شماره
صفحات -
تاریخ انتشار 1990