Purification and Characterization of an Extracellular Proteinase Having Milk-Clotting Activity from Enterococcus faecalis TUA2495L

摘要: Lactic acid bacteria (157 stock cultures) were screened for their ability to produce extracellular proteinase with milk-clotting activity. A strain identified as Enterococcus faecalis TUA2495L showed the highest ratio of activity (MCA) (PA). The molecular weight purified enzyme from was estimated be 34–36 kDa by gel filtration and SDS-PAGE. Its isoelectric point about 5.4, Km value on casein (Hammarsten) 0.61% (w/v). optimum temperature 70°C MCA 50°C PA. increased a decrease in pH 7.8 5.8 but PA at 8.0–9.0. Both stable within range 5.5–10.0. inhibited heavy metal ions (Fe2, Cd2, Ni2, Cu2 Al3), SDS EDTA. Reactivation Co2, Mn2 or Zn2 indicates importance these metals catalytic function enzyme. especially active κ-casein, SDS-PAGE analysis that degradation patterns κ-casein Ec. Mucor miehei almost same.