Analysis of survival rates of halophilic microorganisms in solutions containing sulfate and perchlorate ions

• Grant number: 22/01358-5
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: April 01, 2022
• End date: March 31, 2024
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Physical-Chemistry
• Principal Investigator: Fabio Rodrigues
• Grantee: Guilherme Aguiar de Lacerda
• Host Institution: Instituto de Química (IQ). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

Perchlorate and sulfate salts are very abundant on the surface of Mars. Such salts are important for the Martian brines formation due to their high deliquescence and ability to produce solutions with very low eutectic temperatures. These physicochemical properties might allow the existence of liquid water on Mars, whose availability is the main limiting factor for the development and maintenance of life, as we know it on Earth. Thus, microorganisms resistant to perchlorate and sulfate ions are of great interest for astrobiology since they may serve as models for the study of life in Martian brines. Given this fact, this project aims to map the physicochemical conditions necessary for the survival of halophilic microorganisms in aqueous solutions of NaClO4, Mg(ClO4)2, and MgSO4. Therefore, the survival rate of microorganisms isolated from Lagoa Vermelha- a Brazilian hypersaline environment that shows geochemical characteristics analogous to those of the Martian brines- in NaClO4, Mg(ClO4)2, and MgSO4 solutions will be investigated, as well as the tolerance of halophilic microorganisms to different conditions of water activity, ionic strength, and concentration of Na+(aq), Mg2+(aq), ClO4(aq), and SO42-(aq). The results obtained in this project will contribute to microbiological studies of habitability conditions on Mars.(AU)