(1) They compartmentalize terminal steps of anaerobic energy metabolism but, unlike mitochondria, hydrogenosomes cannot use oxygen as an electron acceptor ; they reduce protons to molecular hydrogen.(2) In the MCS, each excited donor can then either transfer its energy to an acceptor or emit fluorescence, according to the rules listed above.(3) Xanthine oxidase uses molecular oxygen as an electron acceptor , resulting in the formation of superoxide radicals.(4) We next wanted to demonstrate the utility of sRET in conditions where the acceptor and donor molecules were not covalently linked.(5) Cotransfection of mCerulean with the mVenus acceptor did not affect fluorescence polarization.(6) The first is the intrinsic polarization of the isolated acceptor emission, which may be a function of its environment and the particular excitation and emission wavelengths used.(7) The results support the idea that the strength of hydrogen bonding reflects the magnitude of the charges on the associated proton donor and acceptor atoms.(8) In this configuration, an excited donor has a higher probability to transfer its energy to a neighboring acceptor than to emit energy as fluorescence.(9) In most organic donor-acceptor systems, ET from a ground-state donor to a ground-state acceptor is usually not favorable because of energy reasons.(10) First, the emission spectrum of the donor molecule must overlap with the absorbance spectrum of the acceptor .(11) The iron - sulphur cluster associated with the Rieske centre of proteins normally functions in electron transfer reactions as it can act as an electron acceptor and donor.(12) Second, carbon tetrachloride is known to act as an electron acceptor .(13) The first step of the Calvin cycle is the addition of carbon dioxide to an acceptor molecule.(14) Normally ET from a ground-state donor to a ground-state acceptor is energetically not favorable.(15) Fluorescence is detected using an emission path image splitter, outfitted with polarizers, that detects the donor fluorescence as well as two polarizations of the acceptor fluorescence.(16) They propose that the relatively low redox potential of hypericin permits it to compete as an electron acceptor , which consequently potentiates its biological activity in the dark, permitting it to interfere with the growth of tumors.
