In Silico and Biochemical Studies on Ribosome-inactivating Proteins (RIPs) from Jatropha Curcas L. and other Plant Species

Abstract

The biodiesel crop Jatropha curcas L. has gained worldwide importance during the last few decades. Apart from production of biodiesel, it has found its use in cosmetic, fertilizer and lubricant industries. It also has been used in traditional medicines for centuries. Various ribosome-inactivating proteins (RIPs) have been reported from different organs of J. curcas. One of the Type I RIP isolated from J. curcas seeds is Curcin 2A. RIPs irreversibly inhibit the protein synthesis by damaging the ribosome machinery of the cells. However, they possess various pharmacological properties. Therefore, they can be used as antibacterial, antiviral, antifungal, anticancerous as well as immunosuppressive agent. To use them as potent drug, it is important to study their structure and function in depth. Therefore, in present study we selected RIP sequences from various plant species to investigate structural and functional relationship using various bioinformatic tools. It revealed that the RIPs from same plant are significantly similar in amino acid length as well as other crucial regions. However, RIPs from other plant species of same type of RIP have a lot of variations. Furthermore, Ramachandran plot analysis revealed that most of the residues reside in the favored region. Thus, validating the structure. The extracts isolated from different organs of J. curcas at different stages of development were investigated for their therapeutic activity in vitro. Where, mature seed protein extracts showed the highest antibacterial potential. Whereas, for anticancerous activity immature seed extracts were found to be most potent when used in lower doses. Similarly polyphenol extracts of J. curcas were investigated for anti-oxidant activity and it was found that immature seeds had highest antioxidant potential. This comprehensive study would help in understanding biomedical, medicinal and traditional aspect about the RIPs.