Simulated calculation of interaction between uranyl and biological macromolecules with phosphorous

Abstract:

[Objective] Micro-nano flake hydrogen-autunite can be rapidly formed on the surface of biological cells. [Methods] Through simulated calculation, we investigated the interaction between uranyl and the biological macromolecules containing phosphorus (BCP) of phospholipid (ubiquitous in organisms), lipopolysaccharide (unique to Gram-negative bacteria), teichoic acid (unique to Gram-positive bacteria), and phytic acid (unique to plants), the interaction energy, and the distance between related atoms. [Results] According to the Monte Carlo analysis, the adsorption energy of teichoic acid, lipopolysaccharide, phospholipid and phytic acid fell between –109 kcal/mol and –114 kcal/mol in the pure uranyl system and the uranyl-carbonate system, and the energy was mainly relaxation deformation adsorption energy (E_deformation). Considering the adsorption ability and adsorption probability, lipopolysaccharide showed the best ability, followed by phospholipid, phytic acid and teichoic acid. The molecular dynamics relaxation showed that U atom mainly interacted with the group containing P in BPC in the case of uranyl interacting with BCP. In the pure uranyl system, U-P distance was the shortest in the presence of lipopolysaccharide and phytic acid (6.662 Å and 6.539 Å, respectively). In the uranyl-carbonate system, the U-P distance was the shortest in the presence of teichoic acid and phospholipid (5.225 Å and 12.472 Å, respectively). This can be explained with the structure of BCP and the acting force on uranyl. To be specific, in both systems, the dominant force of lipopolysaccharide acting on uranyl was electrostatic force, and that of teichoic acid and phytic acid was van der Waals force. As for the forces of phospholipid acting on uranyl, the van der Waals force was comparable to the electrostatic force. [Conclusion] To sum up, the phosphorus atoms in the phosphate groups have affinity for uranium atoms in uranyl in the process of interaction between the four biological macromolecules containing phosphorus and uranyl ions.