Open AccessStructural characterization of toxic cyclic peptides from blue-green algae by tandem mass spectrometry.
Author(s) -
Thaiya Krishnamurthy,
Linda L. Szafraniec,
Donald F. Hunt,
Jeffrey Shabanowitz,
John R. Yates,
Christoph Hauer,
Wayne W. Carmichael,
Olav M. Skulberg,
Geoffrey A. Codd,
Stephen R. Missler
Publication year - 1989
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.011
H-Index - 771
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.86.3.770
Subject(s) - dehydroalanine , cyclic peptide , chemistry , blue green algae , tandem mass spectrometry , amino acid , residue (chemistry) , derivatization , mass spectrometry , peptide , stereochemistry , algae , structural motif , peptide sequence , cyanobacteria , biochemistry , chromatography , bacteria , biology , botany , genetics , gene
Combined use of chemical degradation, derivatization, and tandem mass spectrometry for rapid structural characterization of toxic cyclic peptides from blue-green algae at the nanomole level is described. Previously, all blue-green algal toxins were thought to belong to a family of seven-residue cyclic peptides, having the general structure cyclo-D-Ala-L-Xaa-erythro-beta-methyl-D-isoaspartic acid-L-Yaa-Adda-D-isoglutamic acid-N-methyldehydroalanine, where Xaa and Yaa represent variable amino acids of the L configuration and Adda is 3-amino-9-methoxy-2,6,8-trimethyl-10-phenyl-deca-4,6-dienoic acid. Structural characterization of two additional toxins indicates that further variability can exist within this family of naturally occurring toxic cyclic peptides. Isoaspartic acid and dehydroalanine can substitute for beta-methylisoaspartic acid and N-methyldehydroalanine, respectively.