title: A device to study the effect of space radiation on photosynthetic organisms.
abstract: This research concerns the study of the effects of ionising space radiation on the oxygen-evolving activity of algae and cyanobacteria, focusing our attention on Photosystem II (PS-II), the oxygen-evolving complex. These microorganisms as higher plants, can use light energy to split water molecules and evolve oxygen in a process that produce storable energy-rich products from atmospheric carbon dioxide. Algae and cyanobacteria which can grow in the presence of nutrients and carbonate are expected to be utilised to maintain an oxygen-atmosphere and to constitute biomass in space shuttles. Irradiation was performed in gamma 60Co-sources of different activities; fluorescence techniques in vivo and SDS-PAGE analysis in vitro were used to determine PS-II efficiency during radiation stress. We determined the radiation target on PS-II by immunoblot. We built a miniaturised growth box that preserves constant pressure and temperature to measure automatically photosynthetic activity by a fluorescence sensor, directly in space during a mission in an ASI balloon.
authors.affiliation: Istituto di Chimica Nucleare del CNR, Roma, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Angelini
authors.forename: P
authors.initials: P
authors.lastname: Ragni
authors.forename: D
authors.initials: D
authors.lastname: Esposito
authors.forename: P
authors.initials: P
authors.lastname: Giardi
authors.forename: M L
authors.initials: ML
authors.lastname: Pompili
authors.forename: R
authors.initials: R
authors.lastname: Moscardelli
authors.forename: M T
authors.initials: MT
authors.lastname: Giardi
mesh_terms: D002708:Chlorella / Q000378:metabolism / Q000528:radiation effects*; D000458:Cyanobacteria / Q000378:metabolism / Q000528:radiation effects*; D005720:Gamma Rays; D010100:Oxygen / Q000378:metabolism; D010788:Photosynthesis / Q000528:radiation effects; D045322:Photosynthetic Reaction Center Complex Proteins / Q000378:metabolism / Q000528:radiation effects*; D045332:Photosystem II Protein Complex; D013026:Space Flight
chemical_list: D045322:Photosynthetic Reaction Center Complex Proteins; D045332:Photosystem II Protein Complex; D010100:Oxygen