Thiol metabolism play significant role during cadmium detoxification by Ceratophyllum demersum L.
In the present study, the level of thiols and activity of related enzymes were investigated in coontail (Ceratophyllum demersum L.) plants to analyze their role in combating the stress caused upon exposure to cadmium (Cd; 0-10 microM) for a duration up to 7d. Plants showed the maximum accumulation of 1293 microg Cd g(-1)dw after 7d at 10 microM. Significant increases in the level of total non-protein thiols (NP-SH) including phytochelatins (PCs) as well as upstream metabolites of the PC biosynthetic pathway, cysteine and glutathione (GSH) were observed. In addition, significant increases in the activities of cysteine synthase (CS), glutathione-S-transferase (GST), glutathione reductase (GR), as well as in vitro activation of phytochelatin synthase (PCS), were noticed in response to Cd. In conclusion, under Cd stress, plants adapted to a new metabolic equilibrium of thiols through coordinated synthesis and consumption to combat Cd toxicity and to accumulate it.
Mishra
Seema
S
Ecotoxicology and Bioremediation Group, National Botanical Research Institute, Rana Pratap Marg, Lucknow, Uttar Pradesh, India. seemam78@rediffmail.com
Tripathi
R D
RD
Srivastava
Sudhakar
S
Dwivedi
Sanjay
S
Trivedi
Prabodh Kumar
PK
Dhankher
O P
OP
Khare
A
A
D001673:Biodegradation, Environmental / Q000187:drug effects; D002104:Cadmium / Q000302:isolation & purification* / Q000494:pharmacology; D003545:Cysteine / Q000378:metabolism; D003547:Cysteine Synthase / Q000378:metabolism; D019803:Glutathione Disulfide / Q000378:metabolism; D005980:Glutathione Reductase / Q000378:metabolism; D005982:Glutathione Transferase / Q000378:metabolism; D019684:Magnoliopsida / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism*; D054811:Phytochelatins / Q000378:metabolism; D013438:Sulfhydryl Compounds / Q000378:metabolism*; D013997:Time Factors
D013438:Sulfhydryl Compounds; D002104:Cadmium; D054811:Phytochelatins; D005980:Glutathione Reductase; D005982:Glutathione Transferase; D003547:Cysteine Synthase; D003545:Cysteine; D019803:Glutathione Disulfide