一种新型IIa类细菌素的克隆表达和活性鉴定

Expression and characterization of a new class IIa bacteriocin

摘要:

NB-C1为一种潜在的IIa类细菌素基因，为实现其在大肠杆菌中的高效可溶表达，首先构建了NB-C1蛋白与绿色荧光蛋白 (GFP) 的融合表达载体pIVEX 2.4d-GFP-NB-C1，然后将构建的表达载体转化大肠杆菌BL21(DE3) pLysS，经诱导表达后，重组蛋白GFP-NB-C1以可溶的形式存在于细胞内。经Ni-NTA亲和层析柱分离纯化后，重组融合蛋白的纯度大于95％，产量达36.1 mg/L。抑菌试验表明，纯化后的重组蛋白对单核细胞增生李斯特氏菌具有明显的抑制作用。

Abstract:

NB-C1 gene is a potential class IIa bacteriocin gene. To obtain its soluble expression, NB-C1 was fused with the green fluorescent protein (GFP) gene and a recombinant expression vector pIVEX 2.4d-GFP-NB-C1 was constructed, which was transformed into Escherichia coli BL21(DE3) pLysS. The expressed fusion protein GFP-NB-C1 was purified by Ni-NTA affinity chromatography and the bioactivity was examined using Listeria monocytogenes as the indicator bacteria. The results showed that the expressed fusion protein GFP-NB-C1 was soluble and the final concentration of the purified fusion protein was 36.1 mg/L E. coli culture and had the purity above 95%. The antimicrobial assay of GFP-NB-C1 was analyzed and showed its high activity against Listeria monocytogenes.