Every organism has different potential to accumulate NO3- from the environment. Nitrate reduction processes are perhaps most significant in maintaining water quality by alteration of nitrate to nitrite. A comparative study between the nitrate reductase NR activity of green and blue green algae in presence of heavy metals is being conducted to present a situation where nitrate reductase process may be affected in presence of heavy metals. Metals interacted negatively with the nitrate reductase activity of a blue green alga, Anacystis nidulans and green algae, Chlorella vulgaris in both free and immobilized state. The activity was more repressed in C. vulgaris in presence of Ni compared to Zn and Cd. However, Cd was more toxic to NR activity in A. nidulans (free state). Metal dependent variation between free and immobilized cells were found to be significant (P< 0.01) however, the concentration dependent pattern in the activity between free and immobilized state was non significant in both the test organisms. C.vulgaris is more efficient in conversion of nitrate to nitrite compared to A.nidulans in presence of heavy metals.
Awasthi, M.; Das, D. N., (2005). Impact of Ni, Zn and
Cd on growth rate, photosynthetic activity, nitrate
reductase and alkaline phosphatase activity of free
and immobilized Scenedesmus quadricauda. Algol. Studies, 115 (1), 53-64 (12 Pages), DOI: 10.1127/1864-1318/2005/0115-0053. Abstract
2.
Awasthi, M.; Rai, L. C., (2005). Toxicity of Nickel,
Zinc and Cadmium to nitrate uptake in free and
immobilized cells of Scenedesmus quadricauda. Ecotox. Environ. Safe, 61 (2), 268-272 (5 Pages), DOI: 10.1016/j.ecoenv.2004.12.018.. Full Text
3.
Berges, J. A., (1997). Miniview: Algal nitrate reductases. Eur. J. Phycol., 32, 3-8 (6 Pages), DOI: 10.1080/09541449710001719315. Abstract | Full Text
4.
Bier, J., (2002). Nitrate in groundwater: Sources, Impacts
and Solutions. 6th Symposium on Groundwater Abstract
Camm, E. L.; Stein, J. R., (1974). Some aspects of
nitrogen metabolism of Nodularia spuigena
(Cyanophyceae). Can. J. Bot., 52 (4), 719-726 (8 Pages), DOI: 10.1139/b74-093. Abstract
7.
Campbell, E. R.; Campbell, W. H., (1998). Determination of nitrate in aqueous matrices using
nitrate reductase. Current protocols in field analytical chemistry, supplement 1, Chapter 5 “Water Quality Parameters-Anionsâ€, John Wiley and Sons, Inc.,
8.
Demon, A.; De Bruin, M.; Wolterbeck, H. T., (1988). The influence of pH on trace metal uptake by an alga
(Scenedesmus pannonicus Subsp. Berlin) and fungus
(Aureobasidium pullulans). Environ. Monitor. Assess., 10, 165-173 (9 Pages), DOI: 10.1007/BF00401781. Abstract
9.
Gerloff, G. C.; Fitzerald, G. P.; Skoog, F., (1950). The
isolation, purifica-tion, and culture of blue-green
algae. Am. J. Bot., 37 (3), 216-218 (3 Pages)Abstract
10.
Herbert, D.; Phipps, P. J.; Strange, R. E., (1971). Chemical analysis of microbial cells. Norris, J. R.; Ribbons, D. W. (Ed.), Methods in Microbiology, Academic Press, London, , 209-334 (126 Pages)Abstract | Full Text
11.
Johnson, C. J.; Kross, B. C., (1990). Continuing
importance of nitrate contamination of groundwater
and wells in rural areas. Am. J. Int Med., 18 (4), 449-456 (8 Pages), DOI: 10.1002/ajim.4700180416. Abstract
12.
Knobloch, O.; Tischner, R., (1989). Characterization
of nitrate reductase deficient mutants of Chlorella
sorokiniana. Plant Physiol., 89, 786-791 (6 Pages)Abstract
13.
Lau, P. S.; Tam, N. F. Y.; Wong, Y. S., (1998). Effect of
carrageenan immobilization on the growth,
physiology and nitrate reductase activity of Chlorella
vulgaris. Bioresource Technol., 63 (2), 115-121 (7 Pages)Abstract
14.
Nichols, G. L.; Shehata, S. A. M.; Syrett P. J., (1978). Nitrate reductase deficient mutants of
Chlamydomonas reinhardii: Biochemical
characteristics. J. Gen. Microbiol., 108, 79-88 (10 Pages). Full Text
15.
Solomonson, L. P.; Barber, M. J., (1990). Assimilatory
nitrate reductase: functional properties and
regulation. Plant Mol. Biol., 41, 225-253 (29 Pages), DOI: 10.1146/annurev.pp.41.060190.001301. Abstract
16.
Tripathi, B. N.; Mehta, S. K.; Gaur, J. P., (2004). Recovery of uptake and assimilation of nitrate in
Scenedesmus sp. previously exposed to elevated levels
205
M. Awashti Nitrate reductase activity...
of Cu2+ and Zn2+. J Plant Physiol., 161 (5), 543-549 (7 Pages), DOI: 10.1078/0176-1617-01238. Abstract
17.
US Environmental Protection Agency, (1987). Nitrate/ nitrite health advisory. Washington: US Environmental Protection Agency, Office of Drinking Water.
18.
Vyamazal, J. C., (1987). Toxicity and accumulation of
cadmium with respect to algae and cyanobacteria; A
review. Toxicity Assess., 2, 387-415 (29 Pages)
19.
Zvyagil’skaya, R. A.; Vartapetyan, B. B.; Vov, N. P. L., (1996). Nitrate dissimilation in eukaryotes. Appl. Biochem. Microbiol., 32, 165-169 (5 Pages)