The interrelation of the two c-type cytochromes in Rhodopseudomonas sphaeroides photosynthesis.
نویسنده
چکیده
Photosynthetic electron flow in the bacterium Rhodopseudomonas sphaeroides involves two c-type cytochromes, one membrane-bound and the other a soluble protein, cytochrome c2. Membranes deficient in cytochrome c2 were used for photo-oxidation studies, with and without the addition of purified cytochrome c2. The results favour a series interrelation, membrane cytochrome c-cytochrome c2-reaction centre.
منابع مشابه
Changes in the cytochrome composition of Rhodopseudomonas sphaeroides grown aerobically, photosynthetically and on dimethyl sulphoxide.
Several strains and mutants of Rhodopseudomonas sphaeroides can be grown anaerobically in the dark in the presence of dimethyl sulphoxide as an electron acceptor. During adaptation to this fermentative mode of growth, two major c-type cytochromes are synthesized, one with Mr 45 000 and the second with Mr 20 000 and a midpoint potential of +120 mV. These cytochromes are barely detectable in memb...
متن کاملSuccinate dehydrogenase in Rhodopseudomonas sphaeroides: subunit composition and immunocross-reactivity with other related bacteria.
Antibodies were raised against the succinate dehydrogenase (SDH) present in the chromatophores of phototrophically grown Rhodopseudomonas sphaeroides. Crossed immunoelectrophoresis experiments indicated that the SDH present in the cytoplasmic membranes of heterotrophically grown R. sphaeroides is probably the same enzyme observed in the chromatophores. The enzyme was extracted by Triton X-100 i...
متن کاملProton pumps in bacterial photosynthesis.
We have previously suggested that the cyclic electron-transport chain in Rhodopseudomonas sphaeroides and Rhodopseudomonas capsulata is arranged as two proton pumps operating in series, one pump being associated with the photochemical reaction centre and its immediate secondary donor (cytochrome c2) and acceptor (ubiquinone), and the other with the 'dark' electron transport through which the cy...
متن کاملReduction kinetics of bacterial cytochromes c2.
In a continuing effort to understand the mechanism of electron transfer by c-type cytochromes we have extended our investigations of the oxidation and reduction of Rhodospirillum rubrum cytochrome ct. We have utilized the oxidant, oxidized azurin, and the reductants SOP-, S204*-, sodium ascorbate, and reduced azurin. The results of these studies demonstrate that, as found previously with the ir...
متن کاملProcedure for rapid isolation of photosynthetic reaction centers using cytochrome c affinity chromatography.
Horse heart cytochrome c linked to Sepharose 4B is used to purify reaction centers from Rhodopseudomonas sphaeroides R-26. This procedure allows for an initial recovery of 80-90% of the bacterial reaction centers present in chromatophore membranes. High purity reaction centers (A(280)/A(802) < 1.30) can be obtained with a 30% recovery. Reaction centers from wild-type Rps. sphaeroides and Rps. c...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- The Biochemical journal
دوره 192 2 شماره
صفحات -
تاریخ انتشار 1980