Dissolution of clotted blood from slaughtered cattle by alkaline protease produced by Streptomyces violaceoruber isolated from saline soil in Saudi Arabia

Abstract

Saudi Arabia suffers from the spread of diseases linked to clotted blood leaking from slaughtered livestock. Anticoagulant proteases produced by Streptomyces are used to safely dissolve clotted blood. Halophilic Streptomyces isolates were extracted from saline soil in Saudi Arabia and tested to dissolve clotted blood by protease. The most protease-producing isolate was identified using classical and genetic methods. The protease was precipitated with saturated ammonium sulfate from a batch of blood clots inoculated with the most protease-producing isolates. Streptomyces isolates (410) were recovered from thirty saline soil samples collected from Dammam (170 isolates, 41.4 %), Al-Khobar (126 isolates, 30.8 %) and Al-Ahsa (114 isolates, 27.8 %). Proteolytic activity was observed in 305 isolates including the most protease-producing isolate S295, which showed the highest activity (33.8 mm), and was identified as S. violaceoruber (99 % similarity). Among all isolates, 241 showed partial hemolysis (alpha) and 64 showed complete hemolysis (beta), including isolate S295 that presented the highest hemolytic activity (0.58 %). The alkaline protease was precipitated with saturated ammonium sulfate (60 %), and it was found that its activity was 5.2 U/ml, total activity 24,960 U/ml, specific activity 463 U/mg, purification fold 15.2 and yield 78 %. The purified alkaline protease was electrophoresed as a single band at 45 kDa.