Team:Brasil-USP
Degradation of Natural Rubber
Team Brasil-USP
Brasil-USP team's 2015 project is to develop an innovative
and sustainable solution for a significant environmental
problem:
accumulation of
waste tires
Current recycling techniques demand high energy consumption, and are completely overwhelmed by the annual amount of rubber waste. In addition, natural rubber degradation may take up to 1000 years.
We aim to accelerate this process by genetically engineering microorganisms to express and secrete two crucial enzymes for the degradation of natural rubber: RoxA (Rubber oxygenase) and Lcp (Latex clearing protein).
Tires and several other products, however, are composed by vulcanized rubber, which ensures its durability and increase its elasticity and strength. In this regard, for vulcanized rubber degradation, the project may include a pre-treatment, which uses Acidithiobacillus ferrooxidans, bacteria that naturally devulcanizes rubber. Both of these processes will be scaled up in bioreactors.
Both of these processes will be scaled up in bioreactors!
The accumulation of scrap (waste) tires constitute in one of the majors causes to the environmental pollution. Because of their size and composition, they are difficult to degrade or recycle, demanding high energy consumption. Additionally, stockpiled tires can easily catch fire and release toxic gases. The volume of waste rubber produced increases annually and now stands at more than 17 million tons, which 65% is scrap tires. In 1999, the Brazilian government approved a resolution that for every tire produced or imported must give an destination to a waste tire. In the same year the National Association of Pneumatic Industries (ANIP) emerged, being responsible for the disposal of tires. Since this resolution, over than 3.11 millions tons of tires were collected in Brazil by ANIP, where 70% of these tires are used in cement industries as an energy source, where the tires are incinerated. Only 30% returns into the market as soled shoes and asphalt, however, these products do not compete with those in the market because of their low quality when compared to products provenients of petrol. Driven by the need to offer a better solution for used tires, an optimized degradation methodology poses as a necessary measure to this environmental challenge, as well as an appealing and smart solution to industries. In this project we report the development of genetically engineering organisms to express and secrete two crucial enzymes for the degradation of natural rubber: RoxA (Rubber oxygenase) and Lcp (Latex clearing protein). Furthermore, a third step will be added in this process to turn our final molecule of degradation into a sustainable and important molecule, with a high value in the market. Moreover, we plan to scale up the process in three reactors containing the genetically modified microorganisms, and chemical reactions to generate the final molecule
Portuguese version...
O acúmulo de pneus inservíveis constituem uma das maiores causas da poluição ambiental. Devido ao seu tamanho e a sua composição, estes são difíceis de degradar ou reciclar, exigindo alto consumo de energia. Além disso, pneus acumulado em terrenos podem facilmente pegar fogo e liberar gases tóxicos. O volume de resíduos produzidos borracha aumenta anualmente e agora em torno de 17 milhões de toneladas, no qual 65% são pneus inservíveis. Em 1999, o governo brasileiro aprovou uma resolução que para cada pneu produzido ou importado deve dar um destino a um pneu de resíduos. No mesmo ano, a Associação Nacional de Indústrias Pneumáticas (ANIP) surgiu sendo responsável pela destinação final desses pneus. Desde essa resolução, cerca de 3,11 milhões de toneladas de pneus foram recolhidos pela ANIP, onde 70% destes pneus são usados em indústrias de cimento como fonte de energia, e os pneus são incinerados. Apenas 30% retorna para o mercado como solas de sapatos e asfalto, no entanto, esses produtos não competem com os do mercado por causa de sua baixa qualidade quando comparados a produtos provenientes do petróleo. Motivados pela necessidade de oferecer uma s olução melhor para pneus usados, uma metodologia de degradação otimizado se coloca como uma medida necessária para este desafio ambiental. Neste projeto nós relatamos o desenvolvimento de organismos geneticamente modificados para expressar e secretar duas enzimas cruciais para a degradação da borracha natural: Roxa (rubber oxigenase) e Lcp (latex clearing protein). Além disso, uma terceira etapa será adicionada neste processo para ligar a molécula final de degradação em uma molécula sustentável de qualidade e com um valor elevado no mercado. Além disso, planejamos expandir o processo para três reatores que contenham os microrganismos geneticamente modificados, e reações químicas para gerar a molécula final.
Our Project
Our project was designed to combat a serious environmental problem worldwide: the accumulation of rubber products waste. For this end, we designed a simple DNA circuit to be expressed in a model bacteria, E.coli. The designed DNA circuit will co-express two essential enzymes for rubber degradation, Lcp and RoxA, followed by their exportation – guaranteeing maximum contact with the threated materials.
Entrepreneurship
Given the high potential for an industrial application, we have investigated possible business strategies that could turn our project into a competitive startup. As a first step, we have met with warehouses where waste tires are treated and discarded to both promote our ideas and learn more on how to implement our system into their reality. Furthermore, we applied an circular business model.
Interlab Study
We also contributed with the Interlab Study, using DH5α E Coli with a backbone plasmid to measure the promter strengths of three promoters from the Anderson's library.
