Effect of chromate on photosynthesis in Cr(VI)-resistant Chlorella

Title:

Effect of chromate on photosynthesis in Cr(VI)-resistant Chlorella

Creator:

Yewalkar, S. N., Dhumal, K. N., and Sainis, J. K.

Identifier:

https://cdk.lib.cas.cz/client/handle/uuid:e3202bde-35e1-4864-bce0-0197e9693e90
uuid:e3202bde-35e1-4864-bce0-0197e9693e90
issn:0300-3604
doi:10.1007/s11099-013-0056-8

Subject:

fotosyntéza, photosynthesis, algae, chromate-resistant, thermoluminescence, 2, and 581

Type:

model:article and TEXT

Format:

bez média and svazek

Description:

Chromate-resistant Chlorella spp. isolated from effluents of electroplating industry could grow in the presence of 30 μM K2Cr2O7. Since photosynthesis is sensitive to oxidative stress, chromate toxicity to photosynthesis was examined in this algal isolate. Chromate [Cr(VI)] up to 100 μM was found to stimulate photosynthesis, while 90% inhibition was found, when the cells were incubated with 1 mM Cr(VI) for 4 h. Photosystem (PS) II was inhibited by 80% and PSI by 40% after such Cr(VI) treatment. Thermoluminescence studies on cells treated with 1 mM Cr(VI) for 4 h showed that S2QA - recombination peak (Q) was shifted to higher temperature, whereas S2/S3QB - recombination peak (B) was shifted to lower temperature. These shifts indicated alga stress response in order to overcome an excitation stress resulting from the inhibition of photosynthesis by Cr(VI). The nontreated Chlorella cells kept in the dark showed periodicity of four for the Q peak (4-8°C) and B peak (34-38°C) after exposure to series of single, turnover, saturating flashes. This periodicity was lost in Cr(VI)-treated cells. Higher concentrations of Cr(VI) inhibited mainly the electron flow in the electron transport chain, inactivated oxygen evolving complex, and affected also Calvin cycle enzymes in the Cr(VI)-resistant isolates of Chlorella. and S. N. Yewalkar, K. N. Dhumal, J. K. Sainis.

Language:

Multiple languages

Rights:

http://creativecommons.org/licenses/by-nc-sa/4.0/
policy:public

Coverage:

565-573

Source:

Photosynthetica | 2013 Volume:51 | Number:4

Harvested from:

CDK

Metadata only:

false