Katanosins

Katanosins are a group of antibiotics (also known as lysobactins). They are natural products with strong antibacterial potency.^[1] So far, katanosin A and katanosin B (lysobactin) have been described.

Additional recommended knowledge

Correct Test Weight Handling Guide: 12 Practical Tips

Guide to balance cleaning: 8 simple steps

How to quickly check pipettes?

Sources

Katanosins have been isolated from the fermentation broth of microorganisms, such as Cytophaga^[2] or the Gram-negative bacterium Lysobacter sp.^[3].

Structure

Katanosins are cyclic depsipeptides (acylcyclodepsipeptides). These proteinogenic structures are not regular proteins from primary metabolism. They origin from the bacterial secondary metabolism. Accordingly, various non-proteinogenic (non-ribosomal) amino acids are found in katanosins, such as 3-hydroxyleucine, 3-hydroxyasparagine, allo-threonine and 3-hydroxyphenylalanine. All katanosins have a cyclic and a linear segment (“lariat structure”). The peptidic ring is closed with an ester bond (lactone). Katanosin A and B differ in the amino acid position 7. The minor metabolite Katanosin A has a valin in this position, whereas the main metabolite katanosin B carries an isoleucine.

Biological Activity

Katanosin antibiotics target the bacterial cell wall biosynthesis. They are highly potent against problematic Gram-positive hospital pathogens such as staphylococci and enterococci. Their promising biological activity attracted various biological and chemical research groups. Their in-vitro potency is comparable with the current “last defence” antibiotic vancomycin.

Chemical Synthesis

The first total syntheses of katanosin B (lysobactin) have been described in 2007.^[4][5]

References

1. ^ D. P. Bonner, J. O´Sullivan, S. K. Tanaka, J. M. Clark, R. R. Whitney, J. Antibiot. 1988, 41, 1745–1751 PMID 3209466
2. ^ J. O´Sullivan, J. E. McCullough, A. A. Tymiak, D. R. Kirsch, W. H. Trejo, P. A. Prinicipe, J. Antibiot. 1988, 41, 1740–1744 PMID 3209465
3. ^ J. I. Shoji, H. Hinoo, K. Matsumoto, T. Hattori, T. Yoshida, S. Matsuura, E. Kondo, J. Antibiot. 1988, 41, 713–718 PMID 3403364
4. ^ F. von Nussbaum, S. Anlauf, J. Benet-Buchholz, D. Häbich, J. Köbberling, L. Musza, J. Telser, H. Rübsamen-Waigmann, N. A. Brunner Angew. Chem. 2007, 119, 2085–2088; Angew. Chem. Int. Ed. 2007, 46, 2039–2042 PMID 17211904
5. ^ A. Guzman-Martinez, R. Lamer, M. S. VanNieuwenhze, J. Am. Chem. Soc. 2007, 129, 6017–6021 PMID 17432854