Team:Missouri Miners/Project

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Revision as of 00:05, 21 April 2012

Overall project

Tuberculosis is caused by a Mycobacteria tuberculosis infection that can arise from ingesting or inhaling M. tuberculosis tubercle bacilli. The bacteria then take residence within the body, mainly the lungs, causing painful lesions and possibly death. The body’s natural defense to M. tuberculosis infections is to ingest the cells by means of endocytes, but all Mycobacterium produce a waxy coating made up of free mycolic fatty acids and the endocytes cannot breakdown the bacteria. I propose to use synthetic biology to create a hybrid protein of the Clostridium cellulovorans’ cellulosome and the peroxisomal multi -functional protein 2 to be able to breakdown extracellular free fatty acids that will allow anti – TB drugs and endocytes to stop the growth or kill the infectious bacteria. This system will implemented into E. coli and further characterization and analysis will be done with those cells.

Project Details

Background

With the advancement of modern medicine Tuberculosis infections still cause many deaths around the world. This increasing number of deaths can be attributed to the emergence of muti- and extreme drug resistant M. tuberculosis strains in large numbers around the world. In recent years total drug resistant (TDR) M. tuberculosis has been discovered in multiple countries (5). India has had the most recent discovery of TDR M. tuberculosis within the past 1-2 years,  following cases documented in Italy in 2007 and Iran in 2009 (5). Typical treatment of TB takes 6-9 months with a rigorous amount of four different anti-TB antibiotics. With this long treatment time comes the opportunity for patients to miss or stop treatment allowing the resistant strains of M. tuberculosis to grow in higher numbers and cause more complications. The treatment for TB is so long due to the bacteria producing a waxy coating consisting of mycolic acids, a complicated fatty acid. This waxy coating causes problems due to the anti-TB drugs being water soluble; not allowing the drugs to get to the cells.

Experimental Design

We propose to create a system that will breakdown the free mycolic acids that are produced by the M. tuberculosis. With the mycolic acids broken down the tuberculosis cells will susceptible to anti-TB drugs and the body’s own immune system. The function of this system will not depend on the E. coli cell’s own metabolism but rather just the exposure to the free mycolic acids. This is due to the hybridization of the cellulosomal dockerin domains of the enzymatic subunits and the peroxisomal multi-function protein 2 enzyme.

Future Steps

• A feedback system that responds to the degradation of mycolic acids
  • A system that is suppressed by the presence of mycolic acids
  • Once turned on it will make the cell produce a newly discovered peptide that inhibits M. tuberculosis growth called lariatins
    • A lot more research will have to go into this step to make it work properly
• Implementation of “Mycolic Acidosome” and feedback systems into a highly engineered non-pathogenic bacteria
  • This bacteria will have multiple fail-safes to have a strict control of its growth and life span

Part 2

The Experiments

Part 3

Results