Induction of apoptosis in human leukemia K562 cells by cyclic lipopeptide from Bacillus subtilis natto T-2

A new cyclic lipopeptide (CLP) purified from Bacillus subtilis natto T-2 dose dependently inhibited growth in human leukemia K562 cells. The results of fluorescent staining indicated that CLP brought about apoptosis in K562 cells. Flow cytometric analysis also demonstrated that CLP caused dose-dependent apoptosis of K562 cells through cell arrest at G1 phase. Western blotting revealed that CLP-induced apoptosis in K562 cells was associated with caspase-3 and poly(ADP-ribose)polymerase (PARP) protein. It is estimated that CLP inhibited proliferation in K562 cells by inducing apoptosis.