Part:BBa_K3776005
AK T369I
This is a feedback insensitive variant of aspartate kinase (AK) in cyanobacteria which enhances lysine biosynthesis. The wild type variant was obtained from Xenorhabdus bovienii then mutated to this feedback insensitive variant AK T359I was characterized by Qi et al.(2011). We codon optimized AK T359I for expression in Synechococcus elongatus UTEX 2973.
In the lysine synthesis pathway in cyanobacteria, L-aspartate is converted L- aspartyl-phosphate then to L-aspartate semialdehyde. L-aspartate semialdehyde is then converted to other molecules for synthesis of amino acids in the aspartate family of amino acids. The conversion of L-aspartate to L- aspartyl-phosphate is catalyzed by AK while AK is subject feedback inhibition by lysine, i.e. high levels of lysine negatively affect AK activity. Removing feedback sensitivity also removes the regulation of lysine biosynthesis by AK, therefore enhancing lysine synthesis yields.(Korosh et al., 2017)
References
Qi, Q., Huang, J., Crowley, J., Ruschke, L., Goldman, B. S., Wen, L., & Rapp, W. D. (2011). Metabolically engineered soybean seed with enhanced threonine levels: biochemical characterization and seed-specific expression of lysine-insensitive variants of aspartate kinases from the enteric bacterium Xenorhabdus bovienii. Plant Biotechnology Journal, 9(2), 193–204. https://doi.org/10.1111/j.1467-7652.2010.00545.x
Korosh, T. C., Markley, A. L., Clark, R. L., McGinley, L. L., McMahon, K. D., & Pfleger, B. F. (2017). Engineering photosynthetic production of L-lysine. Metabolic Engineering, 44, 273–283. https://doi.org/10.1016/j.ymben.2017.10.010
Sequence and Features
- 10COMPATIBLE WITH RFC[10]
- 12COMPATIBLE WITH RFC[12]
- 21INCOMPATIBLE WITH RFC[21]Illegal BglII site found at 1173
- 23COMPATIBLE WITH RFC[23]
- 25INCOMPATIBLE WITH RFC[25]Illegal NgoMIV site found at 145
- 1000COMPATIBLE WITH RFC[1000]
| None |