Merck, M0440-5MG, Mitomycin C from Streptomyces caespitosus

General description
Chemical structure: aziridine
Application
Mitomycin C is produced by a strain of actinomyces, Streptomyces caespitosus. It contains three anticancer moieties, quinine, urethane, and aziridine groups. It is used to generate mitotically inactive feeder cells in cell culture systems, such as the mitotically inactive fibroblasts used in embryonic stem cell systems.
Biochem/physiol Actions
Mode of Action: This product is an alkylating agent that specifically targets the guanine nucleoside sequence 5′-CpG-3′. It inhibits DNA synthesis by covalently reacting with DNA, forming crosslinks between complementary strands of DNA. This interaction prevents separation of complementary DNA strands, inhibiting DNA replication.

Antimicrobial Spectrum: Mitomycin C has strong antitumor activity, especially against Ehrlich ascites tumor cells, and strong bactericidal action against gram-positive and gram-negative bacteria.
Preparation Note
Mitomycin C is soluble in water at .5 mg/mL, with a pH of 6.0-7.5. It undergoes rapid degradation in acidic solutions with pH<6, and is mostly likely to retain activity in solutions with a pH between 6-9.
Disclaimer
Stock solutions should be filter sterilized and stored at 2-8 °C in the dark. Solutions at pH 6-9 can be stored at 0-5 °C for up to a week, but if a precipitate forms, a fresh solution should be prepared - the precipitated solution has been proven toxic to cells.