Part:BBa_K3275000
Arsenic metallothionein
Human arsenic targeting metallothionein
Sequence and Features
- 10COMPATIBLE WITH RFC[10]
- 12COMPATIBLE WITH RFC[12]
- 21INCOMPATIBLE WITH RFC[21]Illegal BamHI site found at 3
- 23COMPATIBLE WITH RFC[23]
- 25COMPATIBLE WITH RFC[25]
- 1000COMPATIBLE WITH RFC[1000]
Introduction
Metallothionein (MT) is a class of small metal-binding proteins that exists in bacteria, plants and animals. These proteins depending on their amino acid compositions have a high binding affinity with different bivalent metal ions. Once MT detects the corresponding metal, it binds the goal through covalent bonds, which are composed of sulfhydryl cysteine residues and stores the metal by tightly chelating the metal. Typically, it is assumed that MTs have two binding domains, one of which is the C-terminal part (α-domain) with three binding sites. The other one is the N-terminal part (β-domain) with four divalent binding sites [1]. Therefore, MTs are important for protecting the cell against heavy metal toxicity and maintaining cellular homeostasis.
Arsenic Metallothionein
As(V) can be reduced to As(III) by arsenate reductase, and then the arsenite can bind to thiol groups easily [2].Metallothionein is a great tool for E.coli to accumulate arsenic because it has a great amount of cysteine, which makes it a thiol-rich protein. part:BBa_K3275000 is from human metallothionein originally, which is called Metallothionein-1A (MT-1A). There are two metal binding domains in MT-1A: the α domain and the β domain. In the α domain, cysteinyl thiolate bridges let 11 cysteine ligands to coordinate with 4 divalent ions, and these ions are chelated with cluster A. In the β domain, the corresponding region, cluster B, helps ligate 3 divalent ions to 9 cysteines [3]. Figure 1 shows the structure of MT-1A [4]
For part:BBa_K3275000, some bases from the original sequence are changed due to synthesis demands.
Characterization
References
- ↑ Ruttkay-Nedecky, B., Nejdl, L., Gumulec, J., Zitka, O., Masarik, M., Eckschlager, T., … Kizek, R. (2013). The role of metallothionein in oxidative stress. International journal of molecular sciences, 14(3), 6044–6066. doi:10.3390/ijms14036044
- ↑ Ngu, T. and Stillman, M. (2006). Arsenic Binding to Human Metallothionein. Journal of the American Chemical Society, 128(38), pp.12473-12483.
- ↑ MT1A - Metallothionein-1A - Homo sapiens (Human) - MT1A gene & protein. (2019). Retrieved from https://www.uniprot.org/uniprot/P04731
- ↑ SWISS-MODEL Repository | P04731. (2019). Retrieved from https://swissmodel.expasy.org/repository/uniprot/P04731?csm=8FBA7C54EE8B6A13
| None |