Nuclear Biology & Nuclear Chemistry - Ligand Field Theory - Non-Elaborate Posts - Post 4

  

In the context of a cytochrome P450 enzyme like CYP51 (lanosterol 14α-demethylase), ligand field strength influences how strongly ligands (including drugs like fluconazole, which binds through nitrogen to the heme iron) can coordinate to the iron-heme center. If the ligand field around the iron is altered (for example by mutation of amino acids near the heme pocket), the ligand (azole drug) may not bind as effectively — the orbital overlap or electron donation/back-bonding required for tight binding may be weakened.

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