‘Cyclotides’ from Shankhpushpi can fight bacteria, virus, say Bengaluru-based scientists

Could injecting a special enzyme into commercial plants make them generate a special kind of plant protein with antibiotic, antiviral, and anticancer properties?

City-based scientists who studied the protein and enzymes say it is possible.

In a new study that was published in Scientific Reports, a team of researchers from the National Centre for Biological Sciences (NCBS) studied the functioning of special circular proteins in plants called “cyclotides”, which the pharma industry uses to stabilise medication.

They can also act as antibiotics, antiviral, and anticancer drugs. The aim of the study, researchers said, was to understand the enzymes which help make cyclotides. “When infused into other commercially important plants, larger amounts of cyclotides can be generated,” a statement from NCBS said, adding that this also made the plant hardier against pests.

Cyclotides can be isolated from several plant families, such as coffee, violets, gourds, and nightshade. The NCBS group focused on the butterfly pea (or Shankhpushpi), which has medical and agricultural applications.

In the study, researchers profiled the plant using transcriptomic and proteomic techniques to identify the pharmaceutically relevant cyclotides.

“Ribonucleotides (RNA) were purified from four different tissues of the plant — pod, stem, leaf, and flower — and the RNA sequence information was compiled and compared across tissues,” said Professor R Sowdhamini, the corresponding author of this paper. Further, protein-study techniques identified the proteins produced.

The intention was to understand the cyclotides and the proteins that help them take their final structure, she added.

Neha V Kalmankar, another researcher, added that the group was keen to identify the enzymes to help the plant make the cyclotides, rather than focusing on finding newer cyclotides.

“Given that we know roughly which enzymes are present in this plant that make these cyclotides, we hope that it will be useful to infuse such enzymes in high amounts into commercially important plants using biotechnology in the future,” she added.

Cyclotides have pharmaceutical potential, but also for pest protection in transgenic crops. The group is working on purifying cyclotides from butterfly pea to the level required for application in agriculture and the pharmaceutical industry.