{"database":"biostudies-literature","file_versions":[],"scores":null,"additional":{"submitter":["Song Y"],"funding":["NCRR NIH HHS","NIGMS NIH HHS"],"pagination":["7949-58"],"full_dataset_link":["https://www.ebi.ac.uk/biostudies/studies/S-EPMC2727071"],"repository":["biostudies-literature"],"omics_type":["Unknown"],"volume":["45(26)"],"pubmed_abstract":["The pK(a)s of ferric aquo-heme and aquo-heme electrochemical midpoints (E(m)s) at pH 7 in sperm whale myoglobin, Aplysia myoblogin, hemoglobin I, heme oxygenase 1, horseradish peroxidase and cytochrome c oxidase were calculated with Multi-Conformation Continuum Electrostatics (MCCE). The pK(a)s span 3.3 pH units from 7.6 in heme oxygenase 1 to 10.9 in peroxidase, and the E(m)s range from -250 mV in peroxidase to 125 mV in Aplysia myoglobin. Proteins with higher in situ ferric aquo-heme pK(a)s tend to have lower E(m)s. Both changes arise from the protein stabilizing a positively charged heme. However, compared with values in solution, the protein shifts the aquo-heme E(m)s more than the pK(a)s. Thus, the protein has a larger effective dielectric constant for the protonation reaction, showin"],"journal":["Biochemistry"],"pubmed_title":["Electrostatic environment of hemes in proteins: pK(a)s of hydroxyl ligands."],"pmcid":["PMC2727071"],"funding_grant_id":["R01 GM064540","R01-GM64540","G12 RR003060","RR03060"],"pubmed_authors":["Gunner MR","Song Y","Mao J"],"additional_accession":[]},"is_claimable":false,"name":"Electrostatic environment of hemes in proteins: pK(a)s of hydroxyl ligands.","description":"The pK(a)s of ferric aquo-heme and aquo-heme electrochemical midpoints (E(m)s) at pH 7 in sperm whale myoglobin, Aplysia myoblogin, hemoglobin I, heme oxygenase 1, horseradish peroxidase and cytochrome c oxidase were calculated with Multi-Conformation Continuum Electrostatics (MCCE). The pK(a)s span 3.3 pH units from 7.6 in heme oxygenase 1 to 10.9 in peroxidase, and the E(m)s range from -250 mV in peroxidase to 125 mV in Aplysia myoglobin. Proteins with higher in situ ferric aquo-heme pK(a)s tend to have lower E(m)s. Both changes arise from the protein stabilizing a positively charged heme. However, compared with values in solution, the protein shifts the aquo-heme E(m)s more than the pK(a)s. Thus, the protein has a larger effective dielectric constant for the protonation reaction, showin","dates":{"release":"2006-01-01T00:00:00Z","publication":"2006 Jul","modification":"2026-05-02T23:39:06.692Z","creation":"2019-03-27T00:24:15Z"},"accession":"S-EPMC2727071","cross_references":{"pubmed":["16800621"],"doi":["10.1021/bi052182l"]}}