N-Acyl homoserine lactone
N-Acyl homoserine lactones (Abbreviated as AHLs or N-AHLs) are a class of signaling molecules involved in bacterial quorum sensing. Quorum sensing is a method of communication between bacteria that enables the coordination of group-based behavior based on population density. They signal changes in gene expression, such as switching between the flagella gene and the gene for pili for the development of a biofilm.
Formation
It arises by the reaction of acyl carrier proteins react with S-adenosylmethionine. The latter donates the equivalent of 4-aminobutyrolactone. Methylthioadenosine is a coproduct.[1]
Homoserine lactone is also a product of the proteolytic reaction of cyanogen bromide (CNBr) with a methionine residue. This reaction is important for chemical sequencing of proteins.
Signalling
In bacterial signalling, N-AHLs are produced within the bacterial cell and released into the environment. N-AHLs produced by different bacteria differ in the length of the R-group side-chain. Chain lengths vary from 4 to 18 carbon atoms and in the substitution of a carbonyl at the third carbon.[2]
See also
- Lactonase
Further reading
- Eberhard, A.; Burlingame, A. L.; Eberhard, C.; Kenyon, G. L.; Nealson, K. H.; Oppenheimer, N. J. (1981). "Structural identification of autoinducer of Photobacterium fischeri luciferase". Biochemistry. 20 (9): 2444–2449. doi:10.1021/bi00512a013. PMID 7236614. (discovery of homoserine lactone)
Notes
- ↑ Parveen, Nikhat; Cornell, Kenneth A. (2011). "Methylthioadenosine/S-adenosylhomocysteine nucleosidase, a critical enzyme for bacterial metabolism". Molecular Microbiology. 79 (1): 7–20. doi:10.1111/j.1365-2958.2010.07455.x. PMC 3057356. PMID 21166890.
- ↑ Kumari, A.; Pasini, P.; Deo, S. K.; Flomenhoft, D.; Shashidhar, S.; Daunert, S. (2006). "Biosensing Systems for the Detection of Bacterial Quorum Signaling Molecules". Analytical Chemistry. 78 (22): 7603–7609. doi:10.1021/ac061421n. PMID 17105149.