Testing antimicrobial surfaces for spaceflight applications and clinical use

Abstract

Inhalt: Built and enclosed environments provide ideal conditions for studying microbial adaptations to defined indoor environments. Humans contribute a majority of the microbial population of enclosed environments and microorganisms are impossible to eliminate from indoor inhabited environments. This applies for spaceflight missions during which the crew lives in indoor conditions with often harsh outside conditions as well as for clinical settings, with patients being especially vulnerable to their environment. Among the omnipresent microorganisms are also opportunistic pathogens, which may cause infections in astronauts and patients alike. In the latter group intensive care patients are especially prone to opportunistic infections. With the ever-increasing antimicrobial resistance of microorganisms posing one of the top ten global public health threats, the need for alternative approaches to tackle this problem is essential. Hence, consideration and evaluation of microbial dispersal, growth, and adaptation during long term missions to prevent contaminations throughout the respective enclosed environment and its potential health impacts is crucial. To evaluate antimicrobial properties and application potential of antimicrobial surfaces for spaceflight purposes and use in clinical settings, surface- microorganism interactions have to be tested in multiple ways: First of all, the surfaces need to be tested under standardized conditions with model organisms in the laboratory to define antimicrobial properties as well as learning more about the mode of action. This is being done using contact killing experiments as well as further going analyses such as proteomics and transcriptomics. Additionally, the surfaces are tested in direct application by frequent touching. This is in the objective of several studies: In the project “Touching Surfaces” novel antimicrobial surfaces are tested application-based under real space conditions on the International Space Station as well as in schools and in clinical settings. Additionally, surfaces are tested in spaceflight analogue habitats such as the Concordia station in Antarctica in the project ConTACTS. For application- based analysis, the microbial community on the surfaces is analyzed using culture-dependent and culture-independent strategies such as next generation sequencing.