Characterization of anticholinesterase-active 3-alkylpyridinium polymers from the marine sponge Reniera sarai in aqueous solutions.
From the marine sponge Reniera sarai 3-alkylpyridinium oligomers and polymers have been isolated. 3-Alkylpyridinium polymers are potent anticholinesterase agents; in addition, they show hemolytic and cytotoxic activities. Oligomers with a molecular weight lower than 3000 Da do not possess any significant activity. We report structural characterization of 3-alkylpyridinium polymers and their behavior in aqueous solutions. We found that biologically active polymers are composed of head-to-tail 3-alkylpyridinium units. According to MALDI-TOF spectrometry two species of polymers exist, the smaller with a molecular weight of 5520 Da and the larger with a molecular weight of 18,900 Da. Both polymers are soluble only in water, while low molecular oligomers are readily soluble in organic solvents. Polymers form large water-dissolved supramolecular structures with an average hydrodynamic radius of 23 +/- 2 nm and, therefore, cannot be separated with size-exclusion chromatography.
Sepcić
K
K
Department of Biology, Biotechnical Faculty, University of Ljubljana, Slovenia.
Guella
G
G
Mancini
I
I
Pietra
F
F
Serra
M D
MD
Menestrina
G
G
Tubbs
K
K
Macek
P
P
Turk
T
T
D000818:Animals; D002800:Cholinesterase Inhibitors / Q000302:isolation & purification / Q000494:pharmacology*; D002850:Chromatography, Gel; D002851:Chromatography, High Pressure Liquid; D008027:Light; D008970:Molecular Weight; D011161:Porifera / Q000737:chemistry*; D011726:Pyridinium Compounds / Q000302:isolation & purification / Q000494:pharmacology*; D012542:Scattering, Radiation; D012996:Solutions; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D013056:Spectrophotometry, Ultraviolet; D014462:Ultrafiltration
D002800:Cholinesterase Inhibitors; D011726:Pyridinium Compounds; D012996:Solutions