title: Tautomycetin is a novel and specific inhibitor of serine/threonine protein phosphatase type 1, PP1.
abstract: Here we isolated tautomycetin, TC, and examined its phosphatase inhibitory activity. Recently we have reported that the left-hand moiety of tautomycin, TM, and the right one containing the spiroketal are essentially required for inhibition of protein phosphatase, PP, and induction of apoptosis, respectively. TC is structurally almost identical to TM except that TC is lacking the spiroketal, which has the potential apoptosis-inducing activity. TC specifically inhibited PP1 activity, IC50 values for purified PP1 and PP2A enzymes being 1.6 and 62 nM, respectively, whereas the IC50 values of TM were 0.21 and 0.94 nM, respectively. These results demonstrate that TC is the most specific PP1 inhibitor out of over 40 species of natural phosphatase inhibitors reported, strongly suggesting that TC is a novel powerful tool to elucidate the physiological roles of PP1 in various biological events.
authors.affiliation: Division of Biochemical Oncology and Immunology, Institute for Genetic Medicine, Hokkaido University, Kita-15, Nishi-7, Kita-ku, Sapporo 060-0815, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Mitsuhashi
authors.forename: N
authors.initials: N
authors.lastname: Matsuura
authors.forename: M
authors.initials: M
authors.lastname: Ubukata
authors.forename: H
authors.initials: H
authors.lastname: Oikawa
authors.forename: H
authors.initials: H
authors.lastname: Shima
authors.forename: K
authors.initials: K
authors.lastname: Kikuchi
mesh_terms: D000818:Animals; D000935:Antifungal Agents / Q000737:chemistry / Q000494:pharmacology*; D001921:Brain / Q000201:enzymology; D004305:Dose-Response Relationship, Drug; D004791:Enzyme Inhibitors / Q000737:chemistry / Q000494:pharmacology*; D005663:Furans; D008055:Lipids; D010749:Phosphoprotein Phosphatases / Q000037:antagonists & inhibitors* / Q000378:metabolism; D010744:Phosphoric Monoester Hydrolases / Q000037:antagonists & inhibitors; D051381:Rats; D013302:Streptomyces / Q000737:chemistry
chemical_list: D000935:Antifungal Agents; D004791:Enzyme Inhibitors; D005663:Furans; D008055:Lipids; C058744:tautomycetin; D010749:Phosphoprotein Phosphatases; D010744:Phosphoric Monoester Hydrolases