Dr. Gaurango Chakrabarty
Research Associate, Department of Inorganic and Physical Chemistry (IPC)
Indian Institute of Science-Bangalore, INDIA
Selenocysteine (Sec or U) is regarded as the 21st proteinogenic amino acid. It exists naturally as a building block of selenoproteins. As many as 25 selenoproteins are known today comprising all three domains of life and mediates several functions. Selenocysteine has a structure similar to that of cysteiene, but with an atom of selenium in place of sulfur. Selenocysteine has both a lower pKa (~5.3) and a lower redox potential than cysteine. These properties make it suitable in proteins that are involved in redox regulation inside cells. Since selenocysteine incorporation into proteins is complex, expression of selenoproteins in a host bacterial cell is difficult using recombinant DNA technology approach. Thus synthesis of polypeptides or proteins containing selenocysteine is best carried out using solid phase peptide synthesis (SPPS). The selenocysteine building block commonly used in SPPS is difficult to synthesize and is very expensive. This prompted us to design a facile method of synthesizing the selenocysteine building block in few easy steps. The synthesized selenocysteine could be incorporated into peptides using SPPS.
Dr Gaurango Chakrabarty completed his doctorate in Bioorganic Chemistry with an emphasis on the therapeutic potential of organoselenium-based compounds from the Indian Institute of Science-Bangalore, India. Currently he is a research associate in the group of Prof. G. Mugesh working in the field of seleno-peptide chemistry. His research interest includes design and synthesis of novel selenium based compounds as therapeutic agents.