Team:IISER-Mohali/Description

 

Project Description

India is one of the world's leading agrarian economies. In this developing nation, the primary sector is responsible for sustaining the second largest population in the world (a means of livelihood for nearly half of them), and contributing more than 17% to the economy. Food grains like rice, wheat and millets constitute an important part of our staple diet. Through the efforts of agencies like the Indian Council of Agriculture Research (ICAR), Central Institute of Post Harvest Engineering & Technology (CIPHET), Department of Agriculture Cooperation & Farmers Welfare (DAC), Department of Agricultural Research and Education (DARE), Directorate of Marketing & Inspection (DMI), and National Bank for Agriculture and Rural Development (NABARD), we have seen a regular increase in their yield, but there remains much to be done to minimize losses at the various levels of production. Upon research, we found various reasons for post harvest losses faced by our farmers: Diseases eg.Yellow rust, ill-timed rain, and Pest infestation - Schistocerca gregaria (Desert locust) in wheat farms.

These losses are prevalent BUT! There exists another source of loss that goes unseen and is often unchecked. These losses occur once good quality grains have been harvested - POST HARVEST LOSSES! In India, post harvest losses amount to 12 to 16 million metric tons of food grains each year. Severely impacted of these are grains like rice, wheat, and millets which constitute an important part of our staple diet. Starvation apart, the resulting monetary losses to farmers are in the excess of Rs.50,000 crores annually. Improper storage is the main problem to be addressed, since it contributes to more than 30% of the total post-harvest loss. Traditional storage modes are vulnerable to rodent pest attacks. Rats eat large quantities of cereals, are vectors for disease causing microbes, and contaminate stored crops with their droppings, fur, and saliva. They are also rapid breeders. Hence, we aim to address this issue with promptness and vigor. Traditional solutions including rodenticides have adverse effects on the environment and other harmless rodents. There are also ethical issues with killing animals (rats are also considered holy by some communities in India).

Extracting the same from cats is impractical, for the following reasons:

  1. The yield/concentration would be insufficient

  2. It’s expensive

  3. Animal Ethics

  4. It would diffuse to the surroundings on extraction.

  5. Unsustainable Industrial synthesis.

WHAT DO WE DO ABOUT IT? WE SOLVE IT!

Research has shown that cat urine contains pheromone precursors and major urinary proteins which mice brains are biologically programmed to perceive as a threat, scurrying away at the slightest detection. This problem inspired us to create FearOmone. “FearOmone- A cat pheromone based Bio-synthetic deterrent to minimize post-harvest losses caused by rat manifestation.”

Hence, we seek a path using the domains of synthetic biology for the efficient production of this pheromone. To do so, the Saccharomyces cerevisiae will be used as a synthetic model, because of the fact that both the substrates that are required for the production of this cat pheromone (felinine) are well characterized and are present in this species of yeast. The felinine pathway found in the cat will be replicated in yeast that has been engineered to produce enzymes necessary for completion of the pathway. FearOmone seeks to exploit the innate fear of murines for cats. Our challenge is to create genetically engineered yeast producing synthetic cat pheromone and prepare a device capable of diffusing this cat pheromone to areas surrounding grain storage facilities, thereby keeping murines away. Our first aim is to transform our host system, Saccharomyces cerevisiae, with necessary synthetic gene circuits which will result in a recombineered yeast that mimics the cat renal pathway for producing felinine.

Great hardware is essential for enhancing the potential of great lab work, more so in our hardware submission. Coupled with intelligent hardware design, the yeast can then be deployed around traditional storage areas. Trace concentrations of this pheromone could deter the from approaching grains, making this an economical solution which harms no animals in the process, and keeps grains safe. It could be easily used by poor farmers, or for small storage purposes, as well as can serve for large storage granaries. Also it could be used anywhere from office places, cafeteria, stationery stores, home kitchens, and hospitals. Indirectly, it helps to prevent vector borne diseases, improving public health. Our rodent deterrent does not harm the environment as the intention is not to kill any organism as done by other rodenticides. It is based on the innate fear caused by a cat pheromone.

In order to systematically enhance and control the production and extraction of our product from our Genetically Modified Organisms (GMO), we have designed a BioReactor along with the subsequent downstream processing to extract our final product. We have used a combination of continuous and batch fed processes. This will lead to the scalability of our project resulting in the industrialization of FearOmone production.

A second part of this project is to intelligently deploy the engineered yeast for maximum effectiveness. Towards this goal we will carry out simulation studies and also intelligently design hardware. Using simulation studies with rats and pheromone diffusion, we aim to create a software that will take as input, dimensions of the storage area, locations of the food grains, etc. Users can provide additional information such as locations of doors, windows and other openings which can serve as entry points for rats. FearOmone will be simulated to be spreading outwards radially with the concentration following a time varying radial distribution from the point of device deployment. We will model the motion of the rats by using Power Law distributions for the step lengths of the rats and modified random walker models for the paths followed by the rats. We will use potential fields to take into account the topography of the storage unit, locations of food grains, and the tendency of rats to follows the sides of walls. EFFUSE - EFflux of FearOmone for optimal USE - This software built using Python uses Molecular Dynamics simulations to determine the rate of diffusion of small molecules out of the cell that are being produced in any compartment of the cell,given the complex environment of the cell. This approach is extrapolated including cell-cell interactions to determine the overall diffusion from an assembly of cells in a culture. Measurement is a vital part of any scientific study, and good measurements lead to great communication of knowledge. Working on the diffusion of a particular small molecule from yeast, we chose to take on a novel project of measuring the diffusion rate of a small molecule in a virtual cell, i.e., to do a measurement test “in-silico”. We combined this diffusion behavior study within the cell with the growth of cells in a culture to give the collective measurement value for the diffusion of the small molecule from a sample of cell culture.