Abstract
The improved Cd2+ surface affinity characteristics of a mutated cyanobacterial metallothionein SmtA (K45C) were investigated via experimental and theoretical methods. Molecular dynamics simulations were carried out using a model of Cd2+ and other ions enclosed in a fully hydrated simulation box with the wild-type or mutated SmtA protein. The theoretical results suggested that mutated SmtA was more powerful in absorption of Cd2+ than the wild-type protein. Then, the mutated smtA gene (from Synechococcus PCC 7942) was synthesized by simplified gene synthesis method and expressed on isopropyl-beta-d-thiogalactopyranoside induction. The protein expression was investigated by SDS-PAGE and verified by Western blotting. Finally, cadmium uptake ratio of mutant protein toward wild type was analyzed by atomic absorption. This study is the first example of cytoplasmic expression of a mutant protein. Experimental results also verified that the mutation intensifies uptake of Cd2+ ions.
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
