Copsin

Copsin is a fungal defensin that acts as an antimicrobial polypeptide secreted from the inky cap mushroom, first reported at the end of 2014. The fungal defensin acts against gram positive bacteria.

History

A group of young common ink cap mushrooms

In October 2014, a collaboration of the Swiss Federal Institute of Technology, Switzerland and the University of Bonn, Germany reported, that they had identified a new antimicrobial peptide, excreted from the inky cap mushroom (Coprinopsis cinereacopsin) grown on horse dung.^[1]

Biosynthesis

Horse manure

The polypeptide was recombinantly produced in a yeast named Pichia pastoris^[1] which grew over five days. the peptide has an extremely compact three-dimensional structure on NMR spectroscopy.^[2]

Mechanism of action

Copsin is an inhibitor of cell wall synthesis by binding to Lipid II.^[3] It was reported to be potent in the petri dish against Gram positive bacteria which have a cell wall, including Enterococcus faecium and Listeria monocytogenes. It is not active against bacteria with an outer membrane, such as gram negative bacteria.^[1]

Potential use

The "exceptionally stable protein", can be boiled at 100 degrees Celsius, can be mixed in strong acid for hours, and can also survive very aggressive enzymes, " remaining completely active". It is considered for use in the food industry for food preservation.^[1]

References

^ ^a ^b ^c ^d Essig A, Hofmann D, Münch D, et al. (12 December 2014). "Copsin, a novel peptide-based fungal antibiotic interfering with the peptidoglycan synthesis". J Biol Chem. 289 (50): 34953–64. doi:10.1074/jbc.M114.599878. PMC 4263892. PMID 25342741.
^ "Copsin antibiotic found in mushroom that grows on horse dung". CBC News. Thomson Reuters. 12 December 2014. Retrieved 17 March 2015.
^ Franzoi, Marco; van Heuvel, Yasemin; Thomann, Susanne; Schürch, Nadia; Kallio, Pauli T.; Venier, Paola; Essig, Andreas (2017-09-19). "Structural Insights into the Mode of Action of the Peptide Antibiotic Copsin". Biochemistry. 56 (37): 4992–5001. doi:10.1021/acs.biochem.7b00697. ISSN 0006-2960. PMID 28825809.

[essig-1] Essig A, Hofmann D, Münch D, et al. (12 December 2014). "Copsin, a novel peptide-based fungal antibiotic interfering with the peptidoglycan synthesis". J Biol Chem. 289 (50): 34953–64. doi:10.1074/jbc.M114.599878. PMC 4263892. PMID 25342741.

[cbc-2] "Copsin antibiotic found in mushroom that grows on horse dung". CBC News. Thomson Reuters. 12 December 2014. Retrieved 17 March 2015.

[3] Franzoi, Marco; van Heuvel, Yasemin; Thomann, Susanne; Schürch, Nadia; Kallio, Pauli T.; Venier, Paola; Essig, Andreas (2017-09-19). "Structural Insights into the Mode of Action of the Peptide Antibiotic Copsin". Biochemistry. 56 (37): 4992–5001. doi:10.1021/acs.biochem.7b00697. ISSN 0006-2960. PMID 28825809.

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