Abstract

Trypsin like protease (TLP) and metalloprotease (MTP) were induced in associated with the mycelium differentiation in Streptomyces albidoflavus SMF301. TLP and MTP were purified and characterized from the culture. The molecular mass of TLP and MTP were estimated to be 32 kDa and 18 kDa, respectively. The molecular mass of TLP and MTP were estimated to be 32 kDa and 18 kDa, respectively. The optimum pH and temperature of TLP were 10 and 40℃. Those of MTP were 8 and 55 ℃. TLP was stable at alkaline pH (6-9) and unstable above 45℃ and MTP was stable at alkaline pH and unstable above 80℃. Km and Vmax values with benzoyl-arginyl p-nitroanilide of TLP were 139 uM, and 10 nmole of nitroanilide released per min per ㎍ protein, respectively. Km, and Vmax values with a synthetic substrate, leucine p-nitroanilide, or MTP were 58.9 uM, 3.47 nmol of nitroanilide released per min per/㎍ protein, respectively. TLP was inhibited competitively by leupeptin; the inhibition constant was 0.0031 uM. MTP was inhibited by EDTA, phenonthroline and bestatin.

• Keywords: Streptomyces albidoflavus; trypsin-like protease; metalloprotease; purification; morphological differentiation