Discovery of selective cystathionine β-synthase inhibitors by high-throughput screening with a fluorescent thiol probe.

A high-throughput assay was developed to identify inhibitors of cystathionine beta-synthase (CBS), which is one of three key enzymes involved in H2S biosynthesis. Screening of 6491 natural compounds identified several selective CBS inhibitors, which suppressed the proliferation of HT29 cancer cells, with IC50 values of less than 10 mu M.