title: The pyrostatins A and B do not inhibit N-acetyl-beta-D-glucosaminidase.
abstract: The compounds pyrostatin A and B, isolated from Streptomyces sp. SA-3501 have been reported as N-acetyl-beta-D-glucosaminidase inhibitors with inhibition constants in the micromolar range. Recently, a comparison of NMR spectral data of the pyrostatins has led to a structural revision of the pyrostatins. It was shown that the pyrostatins A and B are identical to the ectoines 5-hydroxectoine and ectoine, respectively. Ectoines are known as compatible osmolytes in many halophilic and stress-tolerant bacteria. We have performed enzymatic experiments demonstrating that neither ectoine nor 5-hydroxyectoine exhibit an inhibitory effect on N-acetyl-beta-D-glucosaminidase. The previously reported inhibition of N-acetyl-beta-D-glucosaminidase by pyrostatins A and B may thus be due to the contamination of the compound preparations with a strong N-acetyl-beta-D-glucosaminidase inhibitor with an inhibition constant (Ki) in the nanomolar range, as has been reported in other Streptomyces species.
authors: bitop AG, Stockumer Strasse 28, 58453 Witten, Germany.
authors: Daniel
authors: D
authors: Appel
authors: Georg
authors: G
authors: Lentzen
mesh_terms: D000599:Amino Acids, Diamino / Q000737:chemistry / Q000494:pharmacology; D000818:Animals; D002417:Cattle; D004789:Enzyme Activation / Q000187:drug effects*; D007097:Imines / Q000737:chemistry / Q000494:pharmacology*; D007668:Kidney / Q000201:enzymology; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D011759:Pyrrolidines / Q000737:chemistry / Q000494:pharmacology*; D001619:beta-N-Acetylhexosaminidases / Q000037:antagonists & inhibitors / Q000378:metabolism
chemical_list: D000599:Amino Acids, Diamino; D007097:Imines; D011759:Pyrrolidines; C121557:hydroxyectoine; C094715:pyrostatin B; C045628:ectoine; C094714:pyrostatin A; D001619:beta-N-Acetylhexosaminidases