Document Detail

Ionizing radiation impacts photochemical quantum yield and oxygen evolution activity of Photosystem II in photosynthetic microorganisms.
MedLine Citation:
PMID:  19016135     Owner:  NLM     Status:  MEDLINE    
PURPOSE: Long-term space exploration requires biological life support systems capable of coping with the deleterious space environment. The use of oxygenic photosynthetic microorganisms represents an intriguing topic in this context, mainly from the point of view of food and O2 production. The aim of the present study was to assess the effects of space ionizing radiation exposure on the photosynthetic activity of various microorganisms. MATERIALS AND METHODS: Ground-based irradiation experiments were performed using fast neutrons and gamma rays on microorganisms maintained at various light conditions. A stratospheric balloon and a European Space Agency (ESA) flight facility were used to deliver organisms to space at the altitude of 38 and 300 km, respectively. During the balloon flight, the fluorescence activity of the organisms was real-time monitored by means of a special biosensor. RESULTS: The quantum yield of Photosystem II (PSII), measured directly in flight, varied among the microorganisms depending on the light conditions. Darkness and irradiation of cells at 120 and 180 micromol m(-2) s(-1) enhanced the radiation-induced inhibition of photosynthetic activity, while exposure to weaker light irradiance of 20 and 70 micromol m(-2) s(-1) protected the cells against damage. Cell permanence in space reduced the photosynthetic growth while the oxygen evolution capacity of the cells after the flight was enhanced. CONCLUSIONS: A potential role of PSII in capturing and utilizing ionizing radiation energy is postulated.
Giuseppina Rea; Dania Esposito; Mario Damasso; Agnese Serafini; Andrea Margonelli; Cecilia Faraloni; Giuseppe Torzillo; Alba Zanini; Ivo Bertalan; Udo Johanningmeier; Maria T Giardi
Related Documents :
9338105 - The atm gene and protein: possible roles in genome surveillance, checkpoint controls an...
16899625 - Temozolomide-mediated radiation enhancement in glioblastoma: a report on underlying mec...
20214985 - A combined pretreatment of 1,25-dihydroxyvitamin d3 and sodium valproate enhances the d...
3406365 - Cell survival and recovery processes in chinese hamster aa8 cells and in two radiosensi...
6330175 - Eosinophil-mediated injury to lung parenchymal cells and interstitial matrix. a possibl...
93685 - Staining of acid mucopolysaccharides appearing on and in various cell types by dapi.
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  International journal of radiation biology     Volume:  84     ISSN:  0955-3002     ISO Abbreviation:  Int. J. Radiat. Biol.     Publication Date:  2008 Nov 
Date Detail:
Created Date:  2008-11-18     Completed Date:  2009-01-28     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  8809243     Medline TA:  Int J Radiat Biol     Country:  England    
Other Details:
Languages:  eng     Pagination:  867-77     Citation Subset:  IM; S    
IC-CNR, Area of Research of Rome, Department of Agrofood, National Research Council, Rome, Italy.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Algae / cytology,  metabolism*,  radiation effects*
Cell Survival / radiation effects
Electron Transport / radiation effects
Gamma Rays
Oxygen / metabolism*
Photosynthesis / radiation effects*
Photosystem II Protein Complex / metabolism*,  radiation effects*
Space Flight
Reg. No./Substance:
0/Photosystem II Protein Complex; 7782-44-7/Oxygen

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Readability statistics of patient information leaflets in a Speech and Language Therapy Department.
Next Document:  Effects of low-dose gamma irradiation on artemisinin content and amorpha-4,11-diene synthase activit...