Converting waste rubber into a valuable commodity using designed enzymes

Rubber is an essential material found in many everyday items including the tyres on vehicles, medical gloves and contraceptives. Considering the annual global production of rubber has reached 30 million tonnes, it is alarming that the majority of waste material ends up buried in landfills or converted using an energy intensive process into combustible oils.

The estimated 3- 15% of rubber that is recycled using current methods produces inferior material. Therefore, there is an urgent need to develop sustainable methods that can valorise rubber waste.

A rare collection of single-cell organisms that live near waste rubber have been found to degrade and consume waste rubber. These organisms would provide a sustainable method to degrade rubber to smaller chemical fragments that could be reconstituted into high-quality recycled rubber. This process, however, is highly inefficient because the rubber waste contains several compounds that are toxic to the organisms.

To circumvent this, scientists have identified the enzymes used by the organisms to break down rubber. In isolation, these enzymes could be produced on an industrial scale and are more tolerant of toxic chemicals. Despite being promising, enzymes found in nature are only moderately effective at degrading rubber.

This project will apply the knowledge gleaned from natural enzymes to computationally design a set of highly efficient enzymes for the degradation and modification of rubber waste. This goal will be achieved according to the following objectives a) Computational design of novel rubber-degrading enzymes

b) Validate the degradation activity of enzymes with soluble polymers c) Validate enzyme activity on bulk rubber and incorporation of modified rubber into other materials