Intrinsic Properties of Nitric Oxide Binding to Ferrous and Ferric Hemes

Intrinsic Properties of Nitric Oxide Binding to Ferrous and Ferric Hemes†

Gas phase studies offer an ideal medium whereby structural and reactivity properties of charged species may be unveiled in the absence of solvent, matrix or counterion effects. In this environment NO binds to iron(II)and iron(III)-hemes with comparable kinetics and equilibrium parameters, conclusively elucidating the factors determining the widely different affinity in protic solvents or in hem...

Nitric oxide binding to ferric cytochrome P450: a computational study.

The interaction between nitric oxide (NO) and the active site of ferric cytochrome P450 was studied by means of density functional theory (DFT), at the generalized gradient approximation level, and of the SAM1 semiempirical method. The electrostatic effects of the protein environment were included in our DFT scheme by using a hybrid quantum classical approach. The active-site model consisted of...

Feed Additive Name(s): Ferrous chelate of glycine hydrate Ferrous/iron chelate of amino acids hydrate Ferrous fumarate Ferric oxide Ferric chloride hexahydrate Ferrous sulfate monohydrate

Cooperativity in 02 binding to iron porphyrins ( hemoglobin / ferrous hemes / myoglobin / " picket fence " metalloporphyrinates )

The solid-gas 02 binding equilibrium has been studied for ferrous "picketfence" porphyrinates with sterically hindered axial imicazoles. Such systems show significant cooperativity in their binding of 02: at low 02 pressures a low 02 affinifo exists, and at high 02 pressures a higher 02 affinity form develops. Direct analogies are drawn to the cooperativity shown in Oi binding by hemoglobin. Th...

Thermodynamic characterization of ferric and ferrous haem binding to a designed four-alpha-helix protein.

The thermodynamics of ferric and ferrous haem affinity of a de novo designed four-alpha-helix bundle protein and the associated haem electrochemistry is described.