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将啤酒酵母ＮＭＴ基因以Ｎ端融合６个组氨酸的形式（Ｈｉｓ６－ｒＮＭＴ）在Ｅ．ｃｏｌｉＢＬ２１（ＤＥ３）中进行了ＩＰＴＧ诱导的表达研究。ＳＤＳ－ＰＡＧＥ分析确定有与Ｈｉｓ６－ｒＮＭＴ理论分子量一致的诱导表达条带，其表达量占全菌蛋白的１０％左右；表达产物性质分析表明Ｈｉｓ６－ｒＮ－ＭＴ主要以可溶形式存在。在此基础上，利用固定化金属离子（Ｎｉ２＋）配体亲和层析一步纯化目的蛋白，纯度可达９５％以上。体外标记实验证明所得Ｈｉｓ６－ｒＮＭＴ具有与成熟ＮＭＴ相当的酶活力，说明在ＮＭＴ的Ｎ端融合６个组氨酸不影响原酶活性。Ｎ端Ｈｉｓ６的存在使ＮＭＴ能被方便地固定化于Ｎｉ２＋－ＩＤＡＳｅｐｈａｒｏｓｅ６Ｂ树脂上，为从Ｐｈａｇｅｄｉｓｐｌａｙ随机肽库中筛选ＮＭＴ抑制剂打下基础。
The S. cerevisiae NMT gene is fused to N at its 6 histidine form (His6-rNMT). IPTG induced expression in E. coli BL21 (DE3). SDS-PAGE analysis confirmed that His6-rNMT has the same molecular weight as that of His6-rNMT. The expression of His6-rN-MT mainly exists in soluble form. On this basis, the target protein was purified by affinity chromatography using immobilized metal ion (Ni2 +) ligand with the purity of more than 95%. In vitro labeling experiments showed that the resulting His6-rNMT had comparable enzyme activity to mature NMT, indicating that the fusion of 6 histidines at the N-terminus of NMT did not affect the activity of the original enzyme. The presence of N-terminal His6 allows NMT to be conveniently immobilized on Ni2 + -IDASepharose6B resin, laying the foundation for the screening of NMT inhibitors from the phagedisplay random peptide library.