title: Impact of osmotic stress and temperature on pigments and proteins of Anabaena strains.
abstract: A study on Anoboeno strains was carried out to investigate the effect of combined stress of polyethylene glycol 6000 (0,-5 bar and -7 bar) an d temperature (30 degreeC and 45 degreeC) onphotosynthetic pigments (chlorophyll a, carotenoids, phycobilins) and total proteins as stress metabolites. The selected strains, A. oryzoe and A. ellipsosporo were sensitive to osmotic stress at ambient temperature of 30 degreeC and increase in the temperature to 45 degreeC was harmful to the growth of Anoboeno strains. Chlorophyll a contents decreased at 30 degreeC and -7 bar pressure from 8.868 to 0.710 microg ml-1 and 4.360 to 0.220 microg ml-1 in A. oryzae and in A. ellipsospora, respectively and at -7 bar osmotic stress and 45 microC temperature, decrease in Chi a content of A.oryzae was 92.9%, however A. ellipsospora was highly sensitive and could not survive under these conditions. Carotenoids and phycobilins also showed decreasing trends with increase in temperature and osmotic potential. Moreover, combined stress adversely depleted the cellular activities leading to a marked decrease in total protein contents of the cell. A.oryzae and A.ellipsospora showed varying tolerance potential to osmotic and temperature stresses. The results indicated that A. ellipsospora was more sensitive towards these stresses in comparison to A.oryzoe.
authors.affiliation: Department of Biotechnology, S.D.M. PG Girls College, Bhilwara- 311 001, India. ruchi.vic@gmail.com
authors.forename: Ruchi
authors.initials: R
authors.lastname: Sharma
authors.affiliation: Department of Biotechnology, JJT University, Jhunjhunu- 333 001, India
authors.forename: O P
authors.initials: OP
authors.lastname: Chahar
authors.affiliation: Department of Biotechnology, M.D.S University Ajmer -305 009, India.
authors.forename: Monica
authors.initials: M
authors.lastname: Bhatnagar
authors.affiliation: Department of Biotechnology, M.D.S University Ajmer -305 009, India.
authors.forename: Ashish
authors.initials: A
authors.lastname: Bhatnagar
mesh_terms: D017033:Anabaena / Q000235:genetics / Q000254:growth & development / Q000502:physiology*; D001426:Bacterial Proteins / Q000378:metabolism*; D009997:Osmotic Pressure; D010788:Photosynthesis; D010860:Pigments, Biological / Q000378:metabolism*; D011092:Polyethylene Glycols / Q000494:pharmacology; D013696:Temperature
chemical_list: D001426:Bacterial Proteins; D010860:Pigments, Biological; D011092:Polyethylene Glycols