The vitamin D receptor binding peptide, VDRBP, was overexpressed as a fused form with the ubiquitin molecule in Rosetta(DE3)pLysS, a protein production strain of Escherichia coli harboring an induction controller plasmid. The fusion protein was bound to the immobilized metal ions, and the denaturation and renaturation of the fusion protein were performed as a part of the purification procedure. After the elution of the fusion protein, the peptide hormone was released from its fusion partner by using yeast ubiquitin hydrolase (YUH), and subsequently purified by reverse phase chromatography. The purity of the resulting peptide fragment was checked by MALDI-TOF mass and NMR spectroscopy. The final yields of the target peptide were around 5 and 2 mg per liter of LB and minimal media, respectively. The recombinant expression and purification of this peptide will enable structural and functional studies using multidimensional NMR spectroscopy and X-ray crystallography.

中文翻译：

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维生素 D 受体结合肽的重组表达、同位素标记和纯化。

维生素 D 受体结合肽 VDRBP 在 Rosetta(DE3)pLysS（一种含有诱导控制质粒的大肠杆菌蛋白质生产菌株）中以与泛素分子的融合形式过表达。融合蛋白与固定的金属离子结合，融合蛋白的变性和复性是纯化过程的一部分。融合蛋白洗脱后，肽激素通过酵母泛素水解酶（YUH）从其融合伙伴中释放出来，随后通过反相色谱纯化。通过 MALDI-TOF 质谱和 NMR 光谱检查所得肽片段的纯度。目标肽的最终产量分别约为每升 LB 和基本培养基 5 毫克和 2 毫克。