Exocellular peptides from Antarctic psychrophile Pseudoalteromonas Haloplanktis.
Maya Mitova, Maria Luisa Tutino, Giuseppe Infusini, Gennaro Marino, Salvatore De Rosa
Mar Biotechnol (NY) | Published : 2005
A novel diketopiperazine, named cyclo-(D-pipecolinyl-L-isoleucine) (DKP 1), and 7 known diketopiperazines were isolated from the cell-free culture supernatant of the Antarctic psychrophilic bacterium Pseudoalteromonas haloplanktis TAC125. Two diketopiperazines containing pipecolinyl moiety were isolated for the first time from a natural source. Two new linear peptides, stable to bacterial proteolytic enzymes, were also characterized. The structures of the isolated compounds were elucidated by means of spectroscopic data (1D-, 2D-NMR, EIMS, FABMS, and ESIMS/MS) and chiral high-performance liquid chromatography. The potential antioxidant activity of the isolated compounds was evaluated by a DP..View full abstract