Monitoring of Microbial Degraders in Manned Space Stations

Abstract

Samples of microorganisms from the surface of constructions of Mir Space Station (Mir SS) were taken and examined after 13 years of operation. The following microorganisms were isolated and identified: 12 fungal species belonging to the genera Penicillium , Aspergillus , Cladosporium , and Aureobasidium ; 3 yeast species belonging to the genera Debaryomyces , Candida , and Rhodotorula ; and 4 bacterial species belonging to the genera Bacillus , Myxococcus , and Rhodococcus . The predominant species in all samples was Penicillium chrisogenum . It was shown that the fungi isolated could damage polymers and induce corrosion of aluminummagnesium alloys. We commenced a study of microbial degraders on constructions of the Russian section of the International Space Station (RS ISS). Twenty-six species of fungi, bacteria, yeasts, and actinomycetes, known as active biodegraders, were identified in three sample sets taken at intervals. We founded a collection of microorganisms surviving throughout space flights. This collection can be used to test spacecraft production materials, in order to determine their resistance to biodegradation.

Ionizing radiation: how fungi cope, adapt, and exploit with the help of melanin

“…Analysis of the atmosphere in the Russian orbital station Mir revealed the ubiquitous presence of many microorganisms (21). The likely sources of contamination of the space station are flight materials during manufacturing and assembly, the delivery of supplies to the space station, the supplies themselves, and secondary contamination from the crew and any other biological material on board, e.g.…”

“…The likely sources of contamination of the space station are flight materials during manufacturing and assembly, the delivery of supplies to the space station, the supplies themselves, and secondary contamination from the crew and any other biological material on board, e.g. animals, plants and microorganisms used in scientific experiments (21). Fungal contamination poses certain threats to the well-being of the crew not only because some of those fungi are potential human pathogens but also because fungi possess powerful enzymatic systems and secrete various metabolites capable of degrading structural materials inside the spacecraft – from polymers to various alloys.…”

The International Space Station selects for microorganisms adapted to the extreme environment, but does not induce genomic and physiological changes relevant for human health

“…Additionally, some microorganisms might even pose a risk to the material integrity of a spacecraft: So-called technophilic microorganisms, in particular fungi, are able to corrode alloys and polymers used in spacecraft assembly (6). Technophilic microorganisms caused major problems on the former Russian space station Mir (7,8).…”

Effect of the fungus, Aspergillus niger , on the corrosion behaviour of AZ31B magnesium alloy in artificial seawater

“…Up to date, the MIC studies still have been focused on bacteria. Little is known about influence of fungi on electrochemical and biodegradation of metals though some results in these filed have been reported [21][22][23]. Different with bacteria, fungi cannot form relatively A c c e p t e d M a n u s c r i p t 5 homogeneous biofilm on surface; during their growth, hyphae formed by fungi will be adsorbed onto materials, thus, in order to clearly distinguish the difference of MIC between bacteria and fungi, it is necessary to investigate the MIC in the presence of fungi.…”

“…Unlikely widely known bacteria corrosion, A. niger corrosion has only occasionally been reported in the literature [22,23] without an explanation of the underlining bioelectrochemical mechanisms.…”