1. System Biology (ISA5101) Preliminary Project Group 14 g923922 李昀 g925929 何瓊雯

2. Project (Tryptophan) Describe their usage. Find the metabolic pathways involved in the synthesis of the following compound. Find the enzymes and genes involved in these pathway reactions. Is E. Coli suitable for biosynthesis of the above chemicals?

3. Usage of Tryptophan Tryptophan is an amino acid and essential in human nutrition. It is one of the 20 amino acids in the genetic code (codon UGG), and its symbol is Trp or W. Molecular formula : C 11 H 12 N 2 O 2 Molecular weight : 204.23 Tryptophan is also a precursor for serotonin, a neurotransmitter, and melatonin, a neurohormone. Tryptophan was once found to be a safe and reasonably effective sleep aid, probably due to its ability to increase brain levels of serotonin (a calming neurotransmitter when present in moderate levels) and/or melatonin (a drowsiness-inducing hormone secreted by the pineal gland in response to darkness or low light levels).

4. Usage of Tryptophan In particular, tryptophan showed considerable promise as an antidepressant, alone and as an “augmentor” of antidepressant drugs. Other promising indications included relief of chronic pain and reduction of impulsive, violent, manic, addictive, obsessive, or compulsive behaviors and disorders.

5. Metabolic Pathways Involved in the Synthesis of Tryptophan Four major pathways are involved in the synthesis of tryptophan (glucose as the carbon source):  Phosphotransferase System (PTS)  Glycolysis  Pentose Phosphate Pathway  Glycine, serine and threonine metabolism  Pyruvate metabolism  Citrate cycle (TCA cycle)  Phenylalanine, tyrosine and tryptophan biosynthesis

6. Metabolic Pathways Involved in the Synthesis of Tryptophan

13. Enzymes and Genes Enzymes and genes (also CDS) are classified into different categories of major pathways. Also, special notations are made for those involved in more than a single pathway.

14. Is E. Coli suitable for biosynthesis of Trp? Our answer is YES. But HOW? Flux distributions must first to be specified under certain condition. Substances exerting negative or positive control also need to be fully understood and are required to combine with the model of our proposed dynamic system. How to balance the flow between synthesis and consumption? Also, side reactions that are leading to biomass synthesis should not be overlooked in order to ensure sufficient growth.