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Team:WashU/Project
From 2011.igem.org
Background
This year, the WashU team has decided to study the enzymatic pathway responsible for the biosynthesis of B-Carotene and B-Ionone.
Our project, which includes the making of recombinant yeast that produce B-carotene and B-Ionone, is entirely based off the article High-Level Production of Beta-Carotene in Saccharomyces cerevisiae by Successive Transformation with Carotenogenic Genes from Xanthophyllomyces dendrorhous published in Applied and Environmental Microbiology. This paper explains the enzymes required for the B-carotene enzymatic pathway as well as the efficiency of the pathway when certain enzymes are missing or added. This paper can be found here.
Our goal this summer is to recreate this pathway by inserting the crtYB, crtI, and crtE genes into the yeast genome. Additionally, we would like to take this pathway one step further by adding the CCD1 gene which cleaves B-carotene to produce B-ionone. Both of these compounds have the potential to be commercially relevant to the yeast-production industry. Transgenic yeast that produces B-carotene could theoretically be used in the same manner that baker's yeast is used currently. When the GMO yeast is added to bread or other baked goods, it would produce B-carotene in addition to its normal byproducts which would then be infused in the bread. When consumed by the human body, B-carotene is automatically converted to vitamin A. GMO yeast that produces B-ionone also has the potential to be commerically viable. B-ionone is a fragrant chemical that is characterized by a rose scent and is widely used by the perfume industry. Currently, B-ionone is produced by organic synthesis; however, biosynthesis has the potential to provide an alternative production method for this useful compound.
During the process of creating transgenic yeast that produce B-Carotene and B-Ionone, we plan to BioBrick all four of genes involved in the pathway.
