title: Psammaplin A, a chitinase inhibitor isolated from the Fijian marine sponge Aplysinella rhax.
abstract: Several brominated tyrosine derived compounds, psammaplins A (1), K (2) and L (3) as well as bisaprasin (4) were isolated from the Fijian marine sponge Aplysinella rhax during a bioassay guided isolation protocol. Their structures were determined using NMR and MS techniques. Psammaplin A was found to moderately inhibit chitinase B from Serratia marcescens, the mode of inhibition being non-competitive. Crystallographic studies suggest that a disordered psammaplin A molecule is bound near the active site. Interestingly, psammaplin A was found to be a potent antifungal agent.
authors.affiliation: Marine Natural Products Laboratory, Department of Chemistry, University of Aberdeen, Old Aberdeen AB24 3UE, Scotland, UK.
authors.forename: J N
authors.initials: JN
authors.lastname: Tabudravu
authors.forename: V G H
authors.initials: VG
authors.lastname: Eijsink
authors.forename: G W
authors.initials: GW
authors.lastname: Gooday
authors.forename: M
authors.initials: M
authors.lastname: Jaspars
authors.forename: D
authors.initials: D
authors.lastname: Komander
authors.forename: M
authors.initials: M
authors.lastname: Legg
authors.forename: B
authors.initials: B
authors.lastname: Synstad
authors.forename: D M F
authors.initials: DM
authors.lastname: van Aalten
mesh_terms: D000818:Animals; D000935:Antifungal Agents / Q000737:chemistry / Q000302:isolation & purification; D020134:Catalytic Domain; D002688:Chitinases / Q000037:antagonists & inhibitors*; D004220:Disulfides / Q000737:chemistry / Q000302:isolation & purification*; D004791:Enzyme Inhibitors / Q000737:chemistry / Q000302:isolation & purification; D007313:Insecta / Q000187:drug effects; D007306:Insecticides / Q000737:chemistry / Q000302:isolation & purification; D007700:Kinetics; D015394:Molecular Structure; D010940:Plant Proteins / Q000037:antagonists & inhibitors; D011161:Porifera / Q000737:chemistry*; D013172:Spores, Fungal / Q000187:drug effects; D014443:Tyrosine / Q000031:analogs & derivatives* / Q000737:chemistry / Q000302:isolation & purification*
chemical_list: D000935:Antifungal Agents; D004220:Disulfides; D004791:Enzyme Inhibitors; D007306:Insecticides; D010940:Plant Proteins; C098378:psammaplin A; D014443:Tyrosine; D002688:Chitinases; C094255:PLC-B protein, Phytolacca americana