A hybrid non-ribosomal peptide/polyketide synthetase containing fatty-acyl ligase (FAAL) synthesizes the β-amino fatty acid lipopeptides puwainaphycins in the Cyanobacterium Cylindrospermum alatosporum.
Bottom Line:
Bioinformatics analysis enabled sequential prediction of puwainaphycin biosynthesis; this process is initiated by the activation of a fatty acid residue via fatty acyl-AMP ligase and continued by a multidomain non-ribosomal peptide synthetase/polyketide synthetase.High-resolution mass spectrometry and nuclear magnetic resonance spectroscopy measurements proved the production of puwainaphycin F/G congeners differing in FA chain length formed by either 3-amino-2-hydroxy-4-methyl dodecanoic acid (4-methyl-Ahdoa) or 3-amino-2-hydroxy-4-methyl tetradecanoic acid (4-methyl-Ahtea).Because only one puwainaphycin operon was recovered in the genome, we suggest that the fatty acyl-AMP ligase and one of the amino acid adenylation domains (Asn/Gln) show extended substrate specificity.
View Article:
PubMed Central - PubMed
Affiliation: Institute of Microbiology AS CR, v.v.i., Department of Phototrophic Microorganisms - ALGATECH, Třeboň, Czech Republic; Biology Centre of AS CR, v.v.i., Institute of Hydrobiology, České Budějovice, Czech Republic; University of South Bohemia, Faculty of Science, Department of Botany, České Budějovice, Czech Republic.
ABSTRACT
Show MeSH
A putative operon encoding the biosynthetic pathway for the cytotoxic cyanobacterial lipopeptides puwainphycins was identified in Cylindrospermum alatosporum. Bioinformatics analysis enabled sequential prediction of puwainaphycin biosynthesis; this process is initiated by the activation of a fatty acid residue via fatty acyl-AMP ligase and continued by a multidomain non-ribosomal peptide synthetase/polyketide synthetase. High-resolution mass spectrometry and nuclear magnetic resonance spectroscopy measurements proved the production of puwainaphycin F/G congeners differing in FA chain length formed by either 3-amino-2-hydroxy-4-methyl dodecanoic acid (4-methyl-Ahdoa) or 3-amino-2-hydroxy-4-methyl tetradecanoic acid (4-methyl-Ahtea). Because only one puwainaphycin operon was recovered in the genome, we suggest that the fatty acyl-AMP ligase and one of the amino acid adenylation domains (Asn/Gln) show extended substrate specificity. Our results provide the first insight into the biosynthesis of frequently occurring β-amino fatty acid lipopeptides in cyanobacteria, which may facilitate analytical assessment and development of monitoring tools for cytotoxic cyanobacterial lipopeptides. |
![]() Related In:
Results -
Collection
License getmorefigures.php?uid=PMC4219810&req=5
pone-0111904-g001: Gene arrangement, functional annotation and domain structure of the puw gene cluster (56.7 kbp) from Cylindrospermum alatosporum CCALA 988. Mentions: After the final assembly of Illumina and Sanger sequencing data, the predicted puwainaphycin biosynthesis pathway was recovered in the middle of a ∼100-kbp long contig, with >20 kbp flanks at each side to ensure that the full pathway was sequenced. The putative biosynthetic gene cluster was 56,728 bp long and comprised 10 protein-coding ORFs. The ORFs were transcribed starting from a bi-directional promoter region, with orf2, puwA and orf1 transcribed in one direction and puwB-H in the opposite direction (Figure 1). The functional annotation of the individual enzymes and catalytic domains is summarized in Figure 1 and Table S3. |
View Article: PubMed Central - PubMed
Affiliation: Institute of Microbiology AS CR, v.v.i., Department of Phototrophic Microorganisms - ALGATECH, Třeboň, Czech Republic; Biology Centre of AS CR, v.v.i., Institute of Hydrobiology, České Budějovice, Czech Republic; University of South Bohemia, Faculty of Science, Department of Botany, České Budějovice, Czech Republic.