Aerucyclamides A and B: isolation and synthesis of toxic ribosomal heterocyclic peptides from the cyanobacterium Microcystis aeruginosa PCC 7806.
Two new modified hexacyclopeptides, aerucyclamides A and B, were isolated from the toxic freshwater cyanobacterium Microcystis aeruginosa PCC 7806. The constitution was assigned by spectroscopic methods, and the configuration determined by chemical degradation and analysis by Marfey's method combined with chemical synthesis. Synthetic aerucyclamide B was obtained through oxidation of aerucyclamide A (MnO2, benzene). The aerucyclamides were found to be toxic to the freshwater crustacean Thamnocephalus platyurus, exhibiting LC50 values for congeners A and B of 30.5 and 33.8 microM, respectively.
Portmann
Cyril
C
Chemical Synthesis Laboratory, SB-ISIC-LSYNC, Swiss Federal Institute of Technology, EPFL, CH-1015 Lausanne, Switzerland.
Blom
Judith F
JF
Gademann
Karl
K
Jüttner
Friedrich
F
D000818:Animals; D003445:Crustacea / Q000187:drug effects*; D005618:Fresh Water / Q000382:microbiology; D046931:Microcystis / Q000737:chemistry*; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular; D010456:Peptides, Cyclic / Q000138:chemical synthesis / Q000737:chemistry / Q000302:isolation & purification / Q000633:toxicity
D010456:Peptides, Cyclic; C531482:aerucyclamide A; C531483:aerucyclamide B