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[Expression and characterization of a new class IIa bacteriocin]
Yan Xie1, Haiqin Chen, Qiuxiang Zhang
1School of Food Science and Technology, Jiangnan University, Wuxi 214122, China.
Sheng Wu Gong Cheng Xue Bao = Chinese Journal of Biotechnology
|October 25, 2011
Summary
Researchers successfully expressed a soluble fusion protein, GFP-NB-C1, from the NB-Cl bacteriocin gene. This purified protein demonstrated high antimicrobial activity against Listeria monocytogenes.
Area of Science:
- Microbiology
- Molecular Biology
- Biochemistry
Background:
- The NB-Cl gene is identified as a potential class IIa bacteriocin, known for its antimicrobial properties.
- Achieving soluble expression of bacteriocin genes can be challenging, hindering their practical application.
Purpose of the Study:
- To achieve soluble expression of the NB-Cl gene.
- To purify and characterize the expressed NB-Cl protein.
- To evaluate the antimicrobial activity of the expressed NB-Cl protein against pathogenic bacteria.
Main Methods:
- Constructed a recombinant expression vector (pIVEX 2.4d-GFP-NB-C1) fusing NB-Cl with Green Fluorescent Protein (GFP).
- Transformed the vector into Escherichia coli BL21(DE3) pLysS for protein expression.
- Purified the soluble fusion protein (GFP-NB-C1) using Ni-NTA affinity chromatography.
- Assessed antimicrobial activity using Listeria monocytogenes as an indicator strain.
Main Results:
- Successfully obtained soluble expression of the GFP-NB-C1 fusion protein.
- Achieved a final purified protein concentration of 36.1 mg/L with purity exceeding 95%.
- Demonstrated significant antimicrobial activity of GFP-NB-C1 against Listeria monocytogenes.
Conclusions:
- The fusion strategy with GFP enables soluble expression of the NB-Cl bacteriocin.
- The purified GFP-NB-C1 fusion protein exhibits potent antimicrobial activity against Listeria monocytogenes.
- This approach facilitates the study and potential application of NB-Cl bacteriocins.
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