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Highly diverse cyanobactins in strains of the genus Anabaena.

ABSTRACT: Cyanobactins are small, cyclic peptides recently found in cyanobacteria. They are formed through proteolytic cleavage and posttranslational modification of short precursor proteins and exhibit antitumor, cytotoxic, or multi-drug-reversing activities. Using genome project data, bioinformatics, stable isotope labeling, and mass spectrometry, we discovered novel cyclic peptides, anacyclamides, in 27 Anabaena strains. The lengths of the anacylamides varied greatly, from 7 to 20 amino acids. Pronounced sequence variation was also detected, and only one amino acid, proline, was present in all anacyclamides. The anacyclamides identified included unmodified proteinogenic or prenylated amino acids. We identified an 11-kb gene cluster in the genome of Anabaena sp. 90, and heterologous expression in Escherichia coli confirmed that this cluster was responsible for anacyclamide production. The discovery of anacyclamides greatly increases the structural diversity of cyanobactins.

SUBMITTER: Leikoski N

PROVIDER: S-EPMC2813007 | biostudies-literature | 2010 Feb

REPOSITORIES: biostudies-literature

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Highly diverse cyanobactins in strains of the genus Anabaena.

Leikoski Niina N Fewer David P DP Jokela Jouni J Wahlsten Matti M Rouhiainen Leo L Sivonen Kaarina K

Applied and environmental microbiology 20091211 3

Cyanobactins are small, cyclic peptides recently found in cyanobacteria. They are formed through proteolytic cleavage and posttranslational modification of short precursor proteins and exhibit antitumor, cytotoxic, or multi-drug-reversing activities. Using genome project data, bioinformatics, stable isotope labeling, and mass spectrometry, we discovered novel cyclic peptides, anacyclamides, in 27 Anabaena strains. The lengths of the anacylamides varied greatly, from 7 to 20 amino acids. Pronounc ...[more]

PMID: 20008171

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Dataset Information

Highly diverse cyanobactins in strains of the genus Anabaena.

Publications

Highly diverse cyanobactins in strains of the genus Anabaena.

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