FunctionNisin is a polycylic antibacterial peptide, with 34 amino acid residues used as a food preservative. Nisin is produced by fermentation using the bacterium Lactococcus lactis. While in general most bacteriocins inhibit only closely related species, nisin is a rare example of a "broad-spectrum" bacteriocin effective against many Gram-positive organisms, including lactic acid bacteria (commonly associated with spoilage), Listeria monocytogenes (a known pathogen), Staphylococcus aureus, Bacillus cereus, Clostridium botulinum, etc. It is also particularly effective against spores. Gram-negative bacteria are protected by their outer membrane but may become susceptible to nisin action after a heat shock or when this is coupled with the chelator EDTA. Nisin is soluble in water and can be effective at levels nearing the parts-per-billion range[1]. RelevanceIn the food industry, it is obtained from the culturing of L. lactis on natural substrates, such as milk or dextrose, and is not chemically synthesized. Nisin is studied as a novel antibiotic due to its antimicrobial activity and as a therapeutic against neck and head squamous cell carcinoma[2]. Structural highlightsThis is a sample scene created with SAT to color by Group, and another to make a transparent representation of the protein. You can make your own scenes on SAT starting from scratch or loading and editing one of these sample scenes. the structure of nisin that is available here is complex of nisin with lipid II. The origin of this structure is from lactococcus lactis. Basic structure of nisin is presented here. You can see the chain fron N (blue) to C (red). Here you can see the peptid in a spacefill presentation.
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5xhb - LlNisin - Lactococcus lactis
1wco - LlNisin + lipid - NMR
2n32 - LlNisin N-terminal - NMR
2n2e - LlNisin C-terminal - NMR
This page was last modified 09:45, 22 November 2021.