caa a22 4500 605481164 CHVBK 20210128100419.0 cr unu---uuuuu 210128e20150601xx s 000 0 eng 10.1007/s11099-015-0096-3 doi (NATIONALLICENCE)springer-10.1007/s11099-015-0096-3 Differential response of photosynthetic apparatus of cyanobacterium Nostoc muscorum to Pb and Cd toxicity [Elektronische Daten] [S. Dixit, D. Singh] Nostoc muscorum cells showed metal-induced decrease in the relative growth, pigment contents, O2 evolution, and Hill activity in response to lead (Pb2+) and cadmium (Cd2+) treatment, which was further accentuated with increase in metal exposure time and metal concentration. I50 concentrations (50% growth inhibitory concentrations) of Pb2+ and Cd2+ for growth of N. muscorum were 55 and 21 μg mL−1, respectively. These results indicated that the cells of N. muscorum were more susceptible to Cd2+ in comparison to Pb2+. The O2 production was relatively more sensitive to both heavy metals (I50: 16 and 10 μg mL−1 of Pb2+ and Cd2+, respectively) than the Hill activity (I50: 61 and 39 μg mL−1 of Pb2+ and Cd2+, respectively). Further, measurement of Hill activity in the presence of metals and electron donors showed that inhibition sites of both Pb2+ and Cd2+ were located on the oxidizing site of PSII. The chlorophyll a (Chl a) and phycobilisome (PB) fluorescence emission spectra showed that energy transfer from Chl a and PB to PSII reaction center was more susceptible to Cd2+ than Pb2+. The Institute of Experimental Botany, 2015 chlorophyll fluorescence nationallicence electrons donors nationallicence heavy metals nationallicence Hill activity nationallicence oxygen evolution nationallicence Chl a : chlorophyll a nationallicence DCPIP : 2,6-dichlorophenol-1-indophenol nationallicence DPC : 1,5-diphenyl carbazide nationallicence I50 : 50% inhibitory concentration nationallicence PB(s) : phycobilisome(s) nationallicence PC : phycocyanin nationallicence Dixit S. Department of Environmental Science, Babasaheb Bhimrao Ambedkar University, Raibareilly Road, 226 025, Lucknow, India aut Singh D. Department of Environmental Science, Babasaheb Bhimrao Ambedkar University, Raibareilly Road, 226 025, Lucknow, India aut Photosynthetica The Institute of Experimental Biology of the Czech Academy of Sciences 53/2(2015-06-01), 223-230 0300-3604 53:2<223 2015 53 11099 https://doi.org/10.1007/s11099-015-0096-3 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s11099-015-0096-3 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Dixit S. Department of Environmental Science, Babasaheb Bhimrao Ambedkar University, Raibareilly Road, 226 025, Lucknow, India aut NATIONALLICENCE 700 1- Singh D. Department of Environmental Science, Babasaheb Bhimrao Ambedkar University, Raibareilly Road, 226 025, Lucknow, India aut NATIONALLICENCE 773 0- Photosynthetica The Institute of Experimental Biology of the Czech Academy of Sciences 53/2(2015-06-01), 223-230 0300-3604 53:2<223 2015 53 11099