The mechanism of channel opening

In the position F, G helix, F / G and B / C loops, which serve as closure pocket with the bound substrate, is the high variability of the primary structure
Therefore, there are many open channels (2e, 2a, 2c, 2ac, 2b, 2f, S, 3, 4). [6]

Using molecular dynamics the structures of bacterial cytochromes P450 found the mechanism through inlet channel 2a. The movement opens with helix F and F / G loop eventually. Helix G, and B / C loop. Unlike mammalian forms in which studies are lacking. They are anchored to the endoplasmic reticulum (ER). It is expected that the tunnel 2a serves as a mediator of hydrophobic substrates to the heme even human forms. Then the channel 2c is an output. [9]

Example of the flexibility.
Isoform of human cytochrome P450 with the bound inhibitor in solvatačním channel (CYP3A4 erythromycin illustrated with bright green sticks model according to the chemical elements).
Green color is shown F/G loop, pink B/C loop. Yellow is for easy reference colored helix I. The space channel, where the inhibitor is demonstrated by the surface layer structure.