Abstract: The food-grade 1398 neutral protease (1398 NprE), produced through fermentation using Bacillus subtilis AS1398, is widely used in food processing industry. However, the quality of present 1398 NprE is rather disfavored, brought by its dark color, unpleasant odors or contamination problem. With the  purpose of development of 1398 NprE liquid products that better meets strict standard of food processing industry, we attempted to purify the protease using sepharose FF column and macroporous resin chromatography, and analysed the target protein with Maldi-Tof spectrometry; DNA and peptide sequences of 1398 NprE were further revealed and characterized by multiple alignment analysis, which laid a solid ground for further studies of strain development for production of better recombinant neutral proteases through genetic engineering biotechnologies.

Key words: 1398 neutral protease, Bacillus subtilis, purification, column chromatography

摘要： 1398食品级蛋白酶是一种由枯草芽胞杆菌1398发酵产生的用于食品加工处理的中性蛋白酶。目前国内生产工艺制取的固体酶制剂存在菌体未分离、产品颜色深、酸臭味大等缺点。本文以开发无色无臭的液体蛋白酶制剂为目的，对蛋白酶的发酵后提取、纯化工艺等进行了深入研究，分别考察了离子交换树脂层析和工业级大孔树脂对发酵液中1398中性蛋白酶的分离纯化效果，对纯化后的蛋白酶进行了Maldi-Tof质谱分析，并对编码该蛋白酶的基因进行了测序和序列分析，为进一步利用基因工程重组技术生产该蛋白酶奠定了研究基础。

关键词: 1398中性蛋白酶, 枯草芽胞杆菌, 蛋白质纯化, 柱层析