Part:BBa_K1378023
TorA-MlrA
Introduction
MlrA coding sequence fused with TorA secretion signal peptide.
MlrA is a 28kDa protease found in Sphingomonas sp. which can cleavage microcystins(MCs).
MlrA is one part of the gene cluster responsible for the ability of MC degradation. The cluster includes four ORFs, mlrA, mlrB, mlrC and mlrD, which can hydrolyze MCs and facilitate absorption of the products as carbon source. MlrA is sometimes referred as a metalprotease by inhibitor studies.
MlrA can cleavage the Adda-Arg bond and causes ring opening.(Fig. 1) The first-step linearized product shows much weaker hepatoxin compared with MCs. In the experiment of mouse bioassay, up to 250 mg/kg of linearized MC-LR shows no toxicity to mouse, much higher than 50% lethal dose 50mg/kg of cyclic MC-LR. Furthermore, the linearization also raise the median inhibition concentration to 95nM, around 160 times higher than original 0.6nM. [1]
A signal peptide is required for the transportation system to recognize the target protein. TorA, as a signal peptide of TAT patheway, Type II secretion system, is one of our selections. The signature of TAT pathway is that the protein will be folded in the cytoplasm and transported into the periplasm.
References
[1] Gehringer, M. M., Milne, P., Lucietto, F., & Downing, T. G. (2005). Comparison of the structure of key variants of microcystin to vasopressin. Environmental toxicology and pharmacology, 19(2), 297-303.
Sequence and Features
- 10COMPATIBLE WITH RFC[10]
- 12COMPATIBLE WITH RFC[12]
- 21COMPATIBLE WITH RFC[21]
- 23COMPATIBLE WITH RFC[23]
- 25INCOMPATIBLE WITH RFC[25]Illegal AgeI site found at 376
Illegal AgeI site found at 505 - 1000COMPATIBLE WITH RFC[1000]
n/a |