The c15 ring of the Spirulina platensis F-ATP synthase: F1/F0 symmetry mismatch is not obligatory.
نویسندگان
چکیده
The oligomeric c ring of the F-ATP synthase from the alkaliphilic cyanobacterium Spirulina platensis was isolated and characterized. Mass spectroscopy analysis indicated a mass of 8,210 Da, reflecting that of a c monomer. The mass increased by 206 Da after treatment with the c-subunit-specific inhibitor dicyclohexylcarbodiimide (DCCD), which indicated modification of the ion-binding carboxylate by DCCD. Atomic force microscopy topographs of c rings from S. platensis showed 15 symmetrically assembled subunits. The c15-mer reported here is the largest c ring that is isolated and does not show the classical c-ring mismatch to the three-fold symmetry of the F1 domain.
منابع مشابه
Properties of the cyanobacterial coupling factor ATPase from Spirulina platensis. II. Activity of the purified and membrane-bound enzymes.
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ورودعنوان ژورنال:
- EMBO reports
دوره 6 11 شماره
صفحات -
تاریخ انتشار 2005