Polyoxidovanadates' interactions with proteins: An overview

Polyoxidovanadates (POVs, previously named polyoxovanadates) are a subgroup of polyoxidometalates (POMs, previously named polyoxometalates) with interesting pharmacological actions that have been tested as potential antidiabetic, antibacterial, antiprotozoal, antiviral, and anticancer drugs. They contain mainly vanadium and are able to interact with proteins, affecting various biological processes. The most studied POV is the isopolyoxidovanadate decavanadate (V₁₀), which interacts with proteins and/or enzymes such as tyrosine protein phosphatases, P-type ATPases, RNA triphosphatases, myosin and actin. However, in many POVs–protein systems, the binding sites and/or the residues involved in the interaction are not identified. In the present review, the interactions of POVs, as well as linear trivanadate (V₃), both linear and cyclic tetravanadate (V₄) and two proposed heptavanadate (V₇; which are better described by V₁₀ molecules), with proteins are described through X-ray crystallographic studies. Interactions with POVs through theoretical and spectroscopic studies of proteins related to muscle contraction, serum, oxidative stress, and diabetes were also discussed. In sum, herein, we describe POVs’ interactions with various proteins including acid phosphatase A, receptor tyrosine kinase, ecto-nucleoside triphosphate diphosphohydrolase (NTPDases), transient receptor potential cation channel (TRPM4), phosphoglucomutases, P-type ATPases, myosin, actin, transferrin, albumin, and glucosidases, among others. The putative POVs’ effects on proteins are impacted by the POV' stability and speciation. The modes of POVs' interactions include H-bond, electrostatic, H-bond + electrostatic, van der Waals, and covalent binding. The spectroscopic, X-ray and computational results, the sites and modes of binding are described in detail.