Competition between abiogenic and biogenic metal cations in biological systems: Mechanisms of gallium's anticancer and antibacterial effect

J Inorg Biochem. 2021 Jan:214:111309. doi: 10.1016/j.jinorgbio.2020.111309. Epub 2020 Nov 10.

Abstract

Metal cations are key players in a plethora of essential biological processes. Over the course of evolution specific biological functions have been bestowed upon two dozen of (biogenic) metal species, some of the most frequently found being sodium, potassium, magnesium, calcium, zinc, manganese, iron, and copper. On the other hand, there is a group of less studied abiogenic metals like lithium, strontium and gallium that possess not known functions in living organisms, but, by mimicking the native ions and/or competing with them for binding to key metalloenzymes, may exert beneficial effect on humans in particular medical conditions. This review summarizes and critically examines the mechanisms of gallium's therapeutic action in anticancer and antibacterial therapies by exploiting the tools of molecular modeling and experimental biochemistry. These approaches allow for identifying key factors for Ga3+ beneficial effect such as the electrostatic interactions with the protein ligands, substrates or bacterial siderophores, intramolecular hydrogen bond formation, and pH and dielectric properties of the medium. Several intriguing questions concerning the gallium competition with the native ferric ion have found their answers.

Keywords: Antibacterial therapy; Anticancer therapy; DFT calculations; Gallium; Ribonucleotide reductase; Siderophores.

Publication types

  • Review

MeSH terms

  • Anti-Bacterial Agents* / chemistry
  • Anti-Bacterial Agents* / therapeutic use
  • Antineoplastic Agents / chemistry
  • Antineoplastic Agents / therapeutic use
  • Gallium* / chemistry
  • Gallium* / therapeutic use
  • Humans
  • Models, Molecular
  • Neoplasms / drug therapy*

Substances

  • Anti-Bacterial Agents
  • Antineoplastic Agents
  • Gallium