Team:ECUST/Rust Remover
Description
Siderophores are small, high-affinity iron chelating agents, and many microorganisms have the ability to secrete them for the acquisition of iron under iron deficiency conditions (because the iron is solid in the general natural environment with very low concentration of iron ions) and transport through membrane transporter. Siderophore is one of the strongest soluble ferric chelators known in the world. The structure and properties of siderophore produced by different organisms vary widely. The types include: catechins, hydroxamates and carboxylates. Belonging to catechins, enterobactin is the strongest siderophore known, binding to the Fe3+ with the affinity (K=1052 M−1), so we will develop our project based on the siderophore system of E. coli.
Design
The natural siderophore producing is affected by the concentration of iron ions. Through the regulation mechanism of Fur, when the iron ion concentration is high, the siderophore gene is inhibited, and thus the siderophore is no longer produced. Therefore, we need to modify the natural siderophore system to initiate the expression of the siderophore gene when the quorum sensing signal molecule HSL is present.
Chorismic acid, an aromatic amino acid precursor, is converted to 2,3-dihydroxybenzoic acid (DHB) by a series of enzymes, EntA, EntB and EntC. An amide linkage of DHB to L-serine is then catalyzed by EntD, EntE, EntF and EntB. Three molecules of the DHB-Ser formed undergo intermolecular cyclization, yielding enterobactin.
Reference
1. Ward, Thomas R.; Andreas Lutz; Serge P. Parel; Jurgen Eusling; Philipp Gutlich; Peter Buglyo & Chris Orvig (1999). "An Iron-Based Molecular Redox Switch as a Model for Iron Release From Enterobactin Via the Salicylate Binding Mode". Inorg. Chem. 38 (22): 5007–5017.
2. Lee, Chi Woo; Ecker, David J.; Raymond, Kenneth N. (1985). "Coordination chemistry of microbial iron transport compounds. 34. The pH-dependent reduction of ferric enterobactin probed by electrochemical methods and its implications for microbial iron transport". J. Am. Chem. Soc. 107 (24): 6920- 6923.
3. J.R. Pollack, J.B. Neilands, Enterobactin (12 March 1970). "an iron transport compound from Salmonella typhimurium". Biochemical and Biophysical Research Communications. 38 (5): 989–992.