Cysteine cathepsins are known to primarily cleave their substrates at reducing and acidic conditions within endo-lysosomes. They have also been linked to extracellular proteolysis. We developed an assay to test for proteolytic processing of a natural substrate by cysteine cathepsins in the extracellular space. Our study emphasizes that the proteolytic functions of cysteine cathepsins in the thyroid are not restricted to endo-lysosomes but include pivotal roles in extracellular substrate utilization. We have approached this by simulating physiological conditions in protease activity assays.
COBISS.SI-ID: 23357479
Cathepsin B (EC 3.4.22.1) is important for intracellular protein degradation and is involved in a number of pathological processes. To clarify the structural properties of the occluding loop upon the binding of stefins, we determined the crystal structure of the complex between wild-type human stefin A and wild-type human cathepsin B. A comparison of the structure of the unliganded cathepsin B with the structure of the proenzyme, its complexes with chagasin and stefin A shows that the magnitude of the shift of the occluding loop is related to the size of the binding region.
COBISS.SI-ID: 24643111
We have determined the pull off distance of interaction between stefin A and cathepsin L with the atom force microscopy, The distance was independantly assessed with combined approaches of crystall structrue determination and kinetic measurmenets with surfcae plasmon resonance. This was the first application of AFM on protease inhibitor interactions. Results provide a nove insight into understanding of cathepsin stefin interactions.
COBISS.SI-ID: 24059943