Purification of collagenases from
The present invention provides a method for purifying Clostridium histolyticum collagenase type I and type II proteins from a complex mixture by subsequently performing a precipitation with ammonium sulfate, hydrophobic interaction chromatography, cation exchange chromatography, and anion chromatography. Conditions are provided which lead to a stabilized, partially purified preparation even after the precipitation step. The method of the invention leads to a quick and efficient removal of other proteolytic activities. The preparations according to the invention provide exceptionally pure and intact collagenase type I and type II proteins which are enzymatically active. The invention also provides blends of the two isolated proteins. The invention further provides the use of the purified collagenase proteins or blends thereof for treating a tissue sample in vitro.
1. A method for purifying Clostridium histolyticum collagenase type I and type II proteins from a complex mixture comprising the steps of
providing the complex mixture dissolved in an aqueous liquid phase,
forming a precipitate of collagenase type I and type II proteins by dissolving ammonium sulfate in the liquid phase,
separating the precipitate from the liquid phase,
dissolving the separated precipitate in an aqueous buffer comprising Ca2+ ions and having a pH between 6.0 and 8.0, and adjusting the conductivity of the buffer with the dissolved precipitate to a value between 50 and 300 mS/cm, thereby forming a complex buffered solution comprising collagenase type I and type II proteins, reducing clostripain proteolytic activity by a factor of between 90 and 150 and reducing tryptic activity by a factor of between 100 and about 400 relative to the respective proteolytic activities in the complex mixture dissolved in the aqueous liquid phase,
extracting the complex buffered solution by contacting it with a hydrophobic stationary phase and adsorbing collagenase type I and type II proteins to the stationary phase,
separating the hydrophobic stationary phase with the adsorbed collagenase type I and type II proteins from the extracted solution, and
eluting the collagenase type I and type II proteins from the stationary phase, thereby purifying the collagenase type I and type II proteins.
2. The method of claim 1 , further comprising the step of further purifying the eluted collagenase type I and type II proteins by cation exchange chromatography, whereby further residual proteolytic activity is further separated from the collagenase type I and type II proteins.
3. The method of claim 2 , wherein the type I and type II proteins obtained after cation exchange chromatography are separated by performing the steps of
contacting the further purified collagenase type I and type II proteins with an anion exchanging stationary phase and adsorbing the collagenase type I and type II proteins to the stationary phase, and
eluting, in separate fractions, collagenase type I and collagenase type II proteins from the stationary phase, whereby collagenase type I and collagenase type II proteins are purified separately.
4. The method of claim 3 , wherein about 82% of the collagenase type I protein in the collagenase type I fraction obtained has a molecular weight of about 114 kDa.
5. The method of claim 3 , wherein about 82% of the collagenase type I protein in the collagenase type I fraction obtained is N-terminally intact.
6. The method of claim 3 , wherein the clostripain activity in the collagenase type I fraction obtained is less than about 0.04 U/mg of protein.
7. The method of claim 3 , wherein about 93% of the collagenase type II protein in the collagenase type II fraction obtained has a molecular weight of about 112 kDa.
8. The method of claim 3 , wherein about 93% of the collagenase type II protein in the collagenase type II fraction obtained is N-terminally intact.
9. The method of claim 3 , wherein the clostripain activity in the collagenase type II fraction obtained is less than about 0.07 U/mg of protein.
10. The method of claim 3 , wherein a first measured amount of collagenase type I protein in the collagenase type I fraction obtained and a second measured amount of collagenase type II protein are blended in a subsequent step.
11. The method of claim 3 , wherein a first measured amount of collagenase type II protein in the collagenase type II fraction obtained and a second measured amount of collagenase type I protein are blended in a subsequent step.