Strategies were explored for inactivating resistance-bearing microorganisms, focusing on a new species (Bacillus horneckii sp. nov.) discovered on the surfaces of the Kennedy Space Center cleanroom facility in which the Phoenix lander was assembled. Two strains that belong to this novel species were isolated and subjected to a comprehensive, polyphasic analysis to characterize their taxonomic position.
Both phenotypic and genotypic analyses clearly indicate that these isolates belong to the genus Bacillus, and represent a novel species. In addition to the phylogenetic affiliation, structurally the spores of this novel bacterium possess an extraneous layer, which might be responsible for increased resistance to space radiation conditions. The chemical characterization of this novel, extraneous layer of spores will reveal the mechanisms behind radiation resistance.