New cyanopeptolins with potential medical applications !

Abstract from a recent paper by Hanna Mazur-Marzec et al., published in Marine Drugs:

“Cyanopeptolins (CPs) are one of the most frequently occurring cyanobacterial peptides, many of which are inhibitors of serine proteases. Some CP variants are also acutely toxic to aquatic organisms, especially small crustaceans. In this study, thirteen CPs, including twelve new variants, were detected in the cyanobacterium Nostoc edaphicum CCNP1411 isolated from the Gulf of Gdańsk (southern Baltic Sea). Structural elucidation was performed by tandem mass spectrometry with verification by NMR for CP962 and CP985. Trypsin and chymotrypsin inhibition assays confirmed the significance of the residue adjacent to 3-amino-6-hydroxy-2-piperidone (Ahp) for the activity of the peptides. Arginine-containing CPs (CPs-Arg2) inhibited trypsin at low IC50 values (0.24–0.26 µM) and showed mild activity against chymotrypsin (IC50 3.1–3.8 µM), while tyrosine-containing CPs (CPs-Tyr2) were selectively and potently active against chymotrypsin (IC50 0.26 µM). No degradation of the peptides was observed during the enzyme assays. Neither of the CPs were active against thrombin, elastase or protein phosphatase 1. Two CPs (CP962 and CP985) had no cytotoxic effects on MCF-7 breast cancer cells. Strong and selective activity of the new cyanopeptolin variants makes them potential candidates for the development of drugs against metabolic disorders and other diseases.”

The work was carried out by researchers of  the University of Gdansk (Poland) and Robert Gordon University (Scotland, UK) and acknowledges CYANOCOST.

Reference (open access):

Mazur-Marzec, Hanna; Fidor, Anna; Cegłowska, Marta; Wieczerzak, Ewa; Kropidłowska, Magdalena; Goua, Marie; Macaskill, Jenny; Edwards, Christine (2018).  Cyanopeptolins with Trypsin and Chymotrypsin Inhibitory Activity from the Cyanobacterium Nostoc edaphicum CCNP1411. Marine Drugs 16(7)


Specific Chemical and Genetic Markers Revealed a Thousands-Year Presence of Toxic Nodularia spumigena in the Baltic Sea

From the abstract of a Cegłowska et al. (2018) paper in Marine Drugs:

In the Baltic Sea, diazotrophic cyanobacteria have been present for thousands of years, over the whole brackish water phase of the ecosystem. However, our knowledge about the species composition of the cyanobacterial community is limited to the last several decades. In the current study, the presence of species-specific chemical and genetic markers in deep sediments were analyzed to increase the existing knowledge on the history of toxic Nodularia spumigena blooms in the Baltic Sea. As chemical markers, three cyclic nonribosomal peptides were applied: the hepatotoxic nodularin, which in the sea was detected solely in N. spumigena, and two anabaenopeptins (AP827 and AP883a) characteristic of two different chemotypes of this species. From the same sediment samples, DNA was isolated and the gene involved in biosynthesis of nodularin, as well as the phycocyanin intergenic spacer region (PC-IGS), were amplified. The results of chemical and genetic analyses proved for the first time the thousands-year presence of toxic N. spumigena in the Baltic Sea. They also indicated that through all this time, the same two sub-populations of the species co-existed.


Cegłowska, M.; Toruńska-Sitarz, A.; Kowalewska, G.; Mazur-Marzec, H. Specific Chemical and Genetic Markers Revealed a Thousands-Year Presence of Toxic Nodularia spumigena in the Baltic Sea. Mar. Drugs 2018, 16, 116.