naa a22 4500 510788300 CHVBK 20180411083310.0 cr unu---uuuuu 180411e20130101xx s 000 0 eng 10.1007/s12298-012-0145-3 doi (NATIONALLICENCE)springer-10.1007/s12298-012-0145-3 Desiccation induced changes in osmolytes production and the antioxidative defence in the cyanobacterium Anabaena sp. PCC 7120 [Elektronische Daten] [Priyanka Singh, Anupam Tiwari, Sureshwar Singh, Ravi Asthana] Cells of Anabaena sp. PCC 7120, a low desiccation tolerant cyanobacterium, was subjected to prolonged desiccation and effect of loss of water was examined on production of osmolytes, and antioxidant response as well as on overall viability in terms of photosynthetic activity. During dehydration (22h), the organism maintained about 98.5% loss of cellular water, yet cells remained viable as about 30% of photosynthetic O2-evolution activity resumed upon hydrating (1h) such cells. In desiccated state, cyanobacterial cells accumulated osmolytes within 1h though their contents decreased thereafter. The highest levels of trehalose (179nmol mg−1 protein), sucrose (805nmol mg−1 protein) and proline (23.2nmol mg−1 protein) were attained within 1h. Chlorophyll a and carotenoid contents also increased within 1h but phycocyanin level showed opposite trend. The oxygen-evolving activity declined in desiccated cyanobacterial biomass while rehydration led to instant recovery, indicating that cells protect the photosynthetic machinery against desiccation. Notwithstanding, activities of antioxidant enzymes (catalase, peroxidase and superoxide dismutase) attained their peaks after 3h of desiccation, though within 10min of rehydration, their levels returned back close to basal activities of the cultured cells. We propose that onset of osmolyte production in conjunction with upshift of antioxidant enzymes apparently protects the cyanobacterial cells from desiccation stress. Prof. H.S. Srivastava Foundation for Science and Society, 2012 Catalase nationallicence Oxygen-evolution nationallicence Peroxidase nationallicence Superoxide dismutase nationallicence Sugars nationallicence Singh Priyanka Centre of Advanced Study in Botany, Banaras Hindu University, 221005, Varanasi, India aut Tiwari Anupam Centre of Advanced Study in Botany, Banaras Hindu University, 221005, Varanasi, India aut Singh Sureshwar Centre of Advanced Study in Botany, Banaras Hindu University, 221005, Varanasi, India aut Asthana Ravi Centre of Advanced Study in Botany, Banaras Hindu University, 221005, Varanasi, India aut Physiology and Molecular Biology of Plants Springer-Verlag 19/1(2013-01-01), 61-68 0971-5894 19:1<61 2013 19 12298 https://doi.org/10.1007/s12298-012-0145-3 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s12298-012-0145-3 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Singh Priyanka Centre of Advanced Study in Botany, Banaras Hindu University, 221005, Varanasi, India aut NATIONALLICENCE 700 1- Tiwari Anupam Centre of Advanced Study in Botany, Banaras Hindu University, 221005, Varanasi, India aut NATIONALLICENCE 700 1- Singh Sureshwar Centre of Advanced Study in Botany, Banaras Hindu University, 221005, Varanasi, India aut NATIONALLICENCE 700 1- Asthana Ravi Centre of Advanced Study in Botany, Banaras Hindu University, 221005, Varanasi, India aut NATIONALLICENCE 773 0- Physiology and Molecular Biology of Plants Springer-Verlag 19/1(2013-01-01), 61-68 0971-5894 19:1<61 2013 19 12298 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer