Carbonic Anhydrase Case Study

Fig: 6 Carbonic anhydrase (CA) activity under heat stress and effect of SIN-1 (peroxynitrite donor). (A) CA activity in sunflower hypocotyls from sunflower plants exposed to high temperature (38o C) and control. (B) Effect of peroxynitrite donor on carbonic anhydrase (CA) activity in sunflower hypocotyls extract from control plants. (C) Effect of peroxynitrite donor on commercial purified bovine carbonic anhydrase activity used as positive control (5 U mgl). (M. Chaki et al. /Nitric Oxide 29 (2013)

In plants carbonic anhydrase present in the chloroplast stroma and very close to Rubisco. Carbonic anhydrase maintain the supply of CO2 for Rubisco activity. Carbonic anhydrase covert the bicarbonate (HCO3-)

S-nitrosylation is reversible process so it is not identify that is tyrosine nitration is reversible or not? like S-nitrosylation. The mechanism of tryptophan nitration is still not know very well. To identify that, is tyrosine nitration help in the tolerance of plant to stress. The enzyme which regulate the nitration is also not known The identification of nitrated proteins from the different organs of the plant under stress and unstressed condition is upcoming requirement.

Conclusion:

This study based on the protein nitration under abiotic stress. Protein nitration is a least abundant post translational modification. In protein mostly tyrosine is identified which undergoes the nitration under the stress conditions. Tyrosine nitration is the indicator of nitrosative stress. Tyrosine nitration induce by the abiotic stress, stress condition leads to the over production of ROS and RNS, superoxide incorporate with the nitric oxide and leads to the production of peroxynitrite, peroxynitrite nitrated the tyrosine hence it worked as nitrating agent. Peroxynitrite react on the ortho position of the tyrosine and formed 3nitro-tyrosine. Hemeperoxidase and peroxynitrite are major nitrating agent. When tyrosine undergoes nitration the