Factors that distort the heme structure in Heme-Nitric Oxide/OXygen-Binding (H-NOX) protein domains. A theoretical study

Tunnels modulate ligand flux in a heme nitric oxide/oxygen binding (H-NOX) domain.

Interior topological features, such as pockets and channels, have evolved in proteins to regulate biological functions by facilitating the diffusion of biomolecules. Decades of research using the globins as model heme proteins have clearly highlighted the importance of gas pockets around the heme in controlling the capture and release of O(2). However, much less is known about how ligand migrat...

A Theoretical Study of Nitric Oxide Reduction in Heme-Copper Oxidase and Nitric Oxide Reductase

FUNCTION OF NON-HEME-BINDING DOMAINS OF THE STAPHYLOCOCCUS AUREUS ISDB PROTEIN IN HEME ASSIMILATION FROM METHEMOGLOBIN by

Picosecond primary structural transition of the heme is retarded after nitric oxide binding to heme proteins.

We investigated the ultrafast structural transitions of the heme induced by nitric oxide (NO) binding for several heme proteins by subpicosecond time-resolved resonance Raman and femtosecond transient absorption spectroscopy. We probed the heme iron motion by the evolution of the iron-histidine Raman band intensity after NO photolysis. Unexpectedly, we found that the heme response and iron moti...

Ligand-induced allostery in the interaction of the Pseudomonas aeruginosa heme binding protein with heme oxygenase.

A heme-dependent conformational rearrangement of the C-terminal domain of heme binding protein (PhuS) is required for interaction with the iron-regulated heme oxygenase (HemO). Herein, we further investigate the underlying mechanism of this conformational rearrangement and its implications for heme transfer via site-directed mutagenesis, resonance Raman (RR), hydrogen-deuterium exchange MS (HDX...