Team:Brasil-SP/Project/Cystatin
From 2014.igem.org
Cystatin C
Cystatin C (Cys C), an inhibitor of cysteine proteases, has 120 amino acid residues and it is produced by all nucleated cells. It is an excellent biomarker for renal dysfunction, especially for the Chronic Kidney Disease (CDK), due to its constant rate in the blood and its independence of the aforementioned variables (diet, gender, ethnicity, age, muscle mass, and others), varying only with changes in the glomerular filtration rate (GFR). More specifically, Cys C levels rises when GFR descreases and falls when the GFR increases.
In order to work with a system capable of detecting a inhibitor like Cys C, choose a enzyme that has its activity inhibited specifically by the Cys C, so we could measure the Cys C levels through alteration in the enzyme activity. Several scientific studies have shown that Cystatin C has inhibitory activity against Papain and Cathepsin S illustrated in the table below.
ABRAHAMSON M.,1994
References
ABRAHAMSON M., Cystatins, Meth. Enzymol. 240: 685-700 (1994)