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Role of Ni(Fe)-macrostructures due to H-bonds in mechanisms of Ni(Fe)ARD action in methionine salvage pathway is discussed. The AFM method was used to research the possibility of the formation of stable supramolecular nanostructures based on Ni(Fe)ARD model systems {Ni(acac) 2 + L 2 + Tyr} (L 2 = NMP (NMP = N-Methyl-2-pirrolidone), His (His = L-Histidine), Tyr (Tyr = L-Tyrosine)-with the assistance of intermolecular H-bonds. In the course of scanning of investigated samples, it has been found that the structures based on model systems are fixed on a surface strongly enough due to H-bonding. The self-assembly-driven growth of the supramolecular structures on modified Silicone surface based on researched complexes, due to H-bonds and perhaps the other non-covalent interactions was observed.

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The possibility of the supramolecular nano structures formation on the basis of iron and nickel heteroligand complexes: Fe x (acac) y 18C6 m (H 2 O) n , and Fe x (acac) y (CTAB) p (H 2 O) q , or Ni 2 (OAc) 3 (acac)L 2 ·2H 2 O (L 2 = MP) − with the assistance of H-bonding, is researched using the AFM method. Formation of different supramolecular nanostructures on the basis of nickel and iron heteroligand complexes as models for Ni(Fe)ARD Dioxygenases may be used for understanding of different actions of these enzymes.

Earlier, we established that nickel or iron heteroligand complexes, which include PhOH (nickel complexes) or tyrosine residue (nickel or iron complexes), are not only hydrocarbon oxidation catalysts (in the case of PhOH), but also simulate the active centers of enzymes (PhOH, tyrosine). The AFM method established the self-organization of nickel or iron heteroligand complexes, which included tyrosine residue or PhOH, into supramolecular structures on a modified silicon surface. Supramolecular structures were formed as a result of H-bonds and other non-covalent intermolecular interactions and, to a certain extent, reflected the structures involved in the mechanisms of reactions of homogeneous and enzymatic catalysis. Using the AFM method, we obtained evidence at the model level in favor of the involvement of the tyrosine fragment as one of the possible regulatory factors in the functioning of Ni(Fe)ARD dioxygenases or monooxygenases of the family of cytochrome P450. The principles of actions of these oxygenases were used to create highly efficient catalytic systems for the oxidation of hydrocarbons.