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Enterocin T, a novel class IIa bacteriocin produced by Enterococcus sp. 812
Yi-Sheng Chen1, Chi-Rong Yu, Si-Hua Ji
1Department of Biotechnology, Ming Chuan University, No. 5 De-Ming Rd., Gui-Shan Township, Taoyuan, 333, Taiwan. yisheng@mail.mcu.edu.tw
Archives of Microbiology
|August 6, 2013
Summary
A novel bacteriocin, enterocin T, was identified from Enterococcus sp. 812 isolated from broccoli. This bacteriocin exhibits activity against Gram-positive bacteria, including Listeria monocytogenes.
Area of Science:
- Microbiology
- Food Science
- Biochemistry
Background:
- Enterococcus sp. 812, isolated from fresh broccoli, produces a bacteriocin with activity against Gram-positive bacteria.
- This bacteriocin shows partial resistance to autoclaving but is inactivated by protease K.
Purpose of the Study:
- To characterize the novel bacteriocin produced by Enterococcus sp. 812.
- To determine the bacteriocin's mass, N-terminal amino acid sequence, and potential classification.
Main Methods:
- Mass spectrometry was used to determine the bacteriocin's molecular mass.
- Edman degradation was employed for N-terminal amino acid sequencing.
- Sequence homology analysis was performed against known bacteriocins.
Main Results:
- The bacteriocin has a mass of approximately 4,521.34 Da.
- A partial N-terminal sequence (NH2-ATYYGNGVYXDKKKXWVEWGQA) was obtained, containing the YGNGV motif characteristic of class IIa bacteriocins.
- The sequence showed homology to enterococcal bacteriocins but was identified as a novel peptide.
Conclusions:
- Enterococcus sp. 812 produces a novel class IIa bacteriocin, designated enterocin T.
- Enterocin T represents a new addition to the family of bacteriocins with potential applications in food preservation and combating bacterial pathogens.
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