Short neuroprotective peptides, ADNF9 and NAP, are structurally disordered and monomeric in PBS.
Activity-dependent neurotrophic factor 9 (ADNF9) and NAP are nine and eight amino acid peptides, which exhibit neuroprotective activity at femtomolar concentrations against cell toxic agents. We have here characterized their structures and interactions with dodecylphosphocholine (DPC) in phosphate-buffered saline (PBS). Circular dichroism analysis showed that ADNF9 and NAP are structurally disordered in PBS independent of peptide concentration and temperature, but appear to assume different secondary structure at increasing temperature. Sedimentation equilibrium analysis showed that both ADNF9 and NAP are monomeric at 37 degrees C, suggesting no self-association under physiological conditions. No secondary structure changes were observed in the presence of DPC, suggesting that ADNF9 and NAP do not interact with lipids.
Arakawa
Tsutomu
T
Alliance Protein Laboratories, 3957 Corte Cancion, Thousand Oaks, CA 91360, USA. Tarakawa2@aol.com
Niikura
Takako
T
Arisaka
Fumio
F
Kita
Yoshiko
Y
D002942:Circular Dichroism; D008970:Molecular Weight; D009414:Nerve Growth Factors / Q000737:chemistry* / Q000302:isolation & purification; D018696:Neuroprotective Agents / Q000737:chemistry* / Q000302:isolation & purification; D009842:Oligopeptides / Q000737:chemistry* / Q000302:isolation & purification; D010767:Phosphorylcholine / Q000031:analogs & derivatives / Q000737:chemistry; D013696:Temperature; D014461:Ultracentrifugation
D009414:Nerve Growth Factors; D018696:Neuroprotective Agents; D009842:Oligopeptides; C410622:activity-dependent neurotrophic factor; D010767:Phosphorylcholine; C028810:dodecylphosphocholine; C425904:davunetide