From Serratia marcescens, antitumor activity

Protease has also been demonstrated to exhibit antitumor activity. Intratumoral microinjection of proteases from Serratia marcescens into mice with sohd tumors resulted in necrosis and solubilization of the tumor mass (53). 

T. Ikekawa, Y. Ikeda, and F. Tukuoka, Antitumor activity of polysaccharides from Serratia marcescens, Gann, 66 (3), 317-318,1975. 

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