Abstract

Bacteria biofilm formation and its complications are of special concern in isolated structures, such as offshore stations, manned submarines and space habitats, as maintenance and technical support are poorly accessible due to costs and/or logistical challenges. In addition, considering that future exploration missions are planned to adventure farther and longer in space, unlocking biofilm formation mechanisms and developing new antifouling solutions are key goals in order to ensure spacecraft’s efficiency, crew’s safety and mission success. In this work, we explored the interactions between Cupriavidus metallidurans, a prevalently identified contaminant onboard the International Space Station, and aerospace grade materials such as the titanium alloy TiAl6V4, the stainless steel AISI 316 (SS316) and Polytetrafluoroethylene (PTFE) or Teflon. Borosilicate glass was used as a control and all surfaces were investigated at two different pH values (5.0 and 7.0). Biofilms were almost absent on stainless steel and the titanium alloy contrary to Teflon and glass that were covered by an extensive biofilm formed via monolayers of scattered matrix-free cells and complex multilayered clusters or communities. Filamentous extracellular DNA structures were observed specifically in the complex multilayered clusters adherent to Teflon, indicating that the employed attachment machinery might depend on the physicochemical characteristics of the surface.

摘要

由于成本和/或后勤方面的挑战，难以获得维护和技术支持，因此细菌生物膜的形成及其并发症在孤立的结构中尤其受到关注，例如海上站、载人潜艇和太空栖息地。此外，考虑到未来的探索任务计划在太空中探索更远更远的时间，解锁生物膜形成机制和开发新的防污解决方案是确保航天器效率、机组人员安全和任务成功的关键目标。在这项工作中，我们探索了Cupriavidus metallidurans之间的相互作用，国际空间站上普遍发现的污染物，以及航空级材料，如钛合金 TiAl6V4、不锈钢 AISI 316 (SS316) 和聚四氟乙烯 (PTFE) 或特氟龙。硼硅酸盐玻璃用作对照，所有表面都在两种不同的 pH 值（5.0 和 7.0）下进行了研究。不锈钢和钛合金上几乎没有生物膜，这与聚四氟乙烯和玻璃相反，它们被通过形成的广泛生物膜覆盖分散的无基质细胞的单层和复杂的多层簇或群落。在附着于特氟隆的复杂多层簇中特别观察到丝状细胞外 DNA 结构，表明所采用的附着机制可能取决于表面的物理化学特性。