FRINK Linked Data Fragments server

Matches in SemOpenAlex for { <https://semopenalex.org/work/W2316303013> ?p ?o ?g. }

• W2316303013 endingPage "3320" @default.
• W2316303013 startingPage "3310" @default.
• W2316303013 abstract "The energetics of a Mn cofactor bound to modified reaction centers were determined, including the oxidation/reduction midpoint potential and free energy differences for electron transfer. To determine these properties, a series of mutants of Rhodobacter sphaeroides were designed that have a metal-ion binding site that binds Mn2+ with a dissociation constant of 1 μM at pH 9.0 (Thielges et al. (2005) Biochemistry 44, 7389-7394). In addition to the Mn binding site, each mutant had changes near the bacteriochlorophyll dimer, P, that resulted in altered P/P+ oxidation/reduction midpoint potentials, which ranged from 480 mV to above 800 mV compared to 505 mV for wild type. The bound Mn2+ is redox active and after light excitation can rapidly reduce the oxidized primary electron donor, P+. The extent of P+ reduction was found to systematically range from a full reduction in the mutants with high P/P+ midpoint potentials to no reduction in the mutant with a potential comparable to wild type. This dependence of the extent of Mn2+ oxidation on the P/P+ midpoint potential can be understood using an equilibrium model and the Nernst equation, yielding a Mn2+/Mn3+ oxidation/reduction midpoint potential of 625 mV at pH 9. In the presence of bicarbonate, the Mn2+/Mn3+ potential was found to be 90 mV lower with a value of 535 mV suggesting that the bicarbonate serves as a ligand to the bound Mn. Measurement of the electron transfer rates yielded rate constants for Mn2+ oxidation ranging from 30 to 120 s(-1) as the P/P+ midpoint potentials increased from 670 mV to approximately 805 mV in the absence of bicarbonate. In the presence of bicarbonate, the rates increased for each mutant with values ranging from 65 to 165 s(-1), reflecting an increase in the free energy difference due to the lower Mn2+/Mn3+ midpoint potential. This dependence of the rate constant on the P/P+ midpoint potential can be understood using a Marcus relationship that yielded limits of at least 150 s(-1) and 290 meV for the maximal rate constant and reorganization energy, respectively. The implications of these results are discussed in terms of the energetics of proteins with redox active Mn cofactors, in particular, the Mn4Ca cofactor of photosystem II." @default.
• W2316303013 created "2016-06-24" @default.
• W2316303013 creator A5057709120 @default.
• W2316303013 creator A5084478928 @default.
• W2316303013 creator A5068413081 @default.
• W2316303013 date "2011-03-31" @default.
• W2316303013 modified "2023-10-16" @default.
• W2316303013 title "Energetics for Oxidation of a Bound Manganese Cofactor in Modified Bacterial Reaction Centers" @default.
• W2316303013 cites W1443985846 @default.
• W2316303013 cites W151496642 @default.
• W2316303013 cites W1631896948 @default.
• W2316303013 cites W1679387364 @default.
• W2316303013 cites W1963741258 @default.
• W2316303013 cites W1964820380 @default.
• W2316303013 cites W1967250117 @default.
• W2316303013 cites W1967702389 @default.
• W2316303013 cites W1967964640 @default.
• W2316303013 cites W1973721002 @default.
• W2316303013 cites W1975695493 @default.
• W2316303013 cites W1976325740 @default.
• W2316303013 cites W1977240745 @default.
• W2316303013 cites W1979776740 @default.
• W2316303013 cites W1987981402 @default.
• W2316303013 cites W1988588272 @default.
• W2316303013 cites W1993156452 @default.
• W2316303013 cites W1995994720 @default.
• W2316303013 cites W1996286489 @default.
• W2316303013 cites W1997270140 @default.
• W2316303013 cites W1997697274 @default.
• W2316303013 cites W2008596194 @default.
• W2316303013 cites W2008743356 @default.
• W2316303013 cites W2009148729 @default.
• W2316303013 cites W2010494742 @default.
• W2316303013 cites W2011890891 @default.
• W2316303013 cites W2014189869 @default.
• W2316303013 cites W2016185790 @default.
• W2316303013 cites W2017781434 @default.
• W2316303013 cites W2028617561 @default.
• W2316303013 cites W2029449965 @default.
• W2316303013 cites W2031904472 @default.
• W2316303013 cites W2038018495 @default.
• W2316303013 cites W2039635953 @default.
• W2316303013 cites W2044952194 @default.
• W2316303013 cites W2051420083 @default.
• W2316303013 cites W2052198153 @default.
• W2316303013 cites W2057863409 @default.
• W2316303013 cites W2058092262 @default.
• W2316303013 cites W2060760513 @default.
• W2316303013 cites W2062778939 @default.
• W2316303013 cites W2063780436 @default.
• W2316303013 cites W2065253540 @default.
• W2316303013 cites W2071329982 @default.
• W2316303013 cites W2071357799 @default.
• W2316303013 cites W2071667796 @default.
• W2316303013 cites W2072450767 @default.
• W2316303013 cites W2073558331 @default.
• W2316303013 cites W2077648822 @default.
• W2316303013 cites W2081022314 @default.
• W2316303013 cites W2083907491 @default.
• W2316303013 cites W2087006788 @default.
• W2316303013 cites W2087460180 @default.
• W2316303013 cites W2088426152 @default.
• W2316303013 cites W2088644683 @default.
• W2316303013 cites W2092054562 @default.
• W2316303013 cites W2095216354 @default.
• W2316303013 cites W2095551065 @default.
• W2316303013 cites W2111969713 @default.
• W2316303013 cites W2118728538 @default.
• W2316303013 cites W2124749781 @default.
• W2316303013 cites W2127132427 @default.
• W2316303013 cites W2128536241 @default.
• W2316303013 cites W2137839040 @default.
• W2316303013 cites W2142647742 @default.
• W2316303013 cites W2146315633 @default.
• W2316303013 cites W2164652962 @default.
• W2316303013 cites W2167153177 @default.
• W2316303013 cites W2312432518 @default.
• W2316303013 cites W277449148 @default.
• W2316303013 doi "https://doi.org/10.1021/bi1017478" @default.
• W2316303013 hasPubMedId "https://pubmed.ncbi.nlm.nih.gov/21375274" @default.
• W2316303013 hasPublicationYear "2011" @default.
• W2316303013 type Work @default.
• W2316303013 sameAs 2316303013 @default.
• W2316303013 citedByCount "18" @default.
• W2316303013 countsByYear W23163030132012 @default.
• W2316303013 countsByYear W23163030132013 @default.
• W2316303013 countsByYear W23163030132014 @default.
• W2316303013 countsByYear W23163030132015 @default.
• W2316303013 countsByYear W23163030132016 @default.
• W2316303013 countsByYear W23163030132017 @default.
• W2316303013 countsByYear W23163030132018 @default.
• W2316303013 countsByYear W23163030132019 @default.
• W2316303013 countsByYear W23163030132020 @default.
• W2316303013 countsByYear W23163030132022 @default.
• W2316303013 countsByYear W23163030132023 @default.
• W2316303013 crossrefType "journal-article" @default.
• W2316303013 hasAuthorship W2316303013A5057709120 @default.
• W2316303013 hasAuthorship W2316303013A5068413081 @default.

• next