摘要 将产黄青霉(Penicillium chrysogenum)来源的β-甘露聚糖酶(PcMan26A)在毕赤酵母中高效表达,经高密度发酵,发酵液酶活力达25200 U/mL。该酶属于GH26家族,与黑曲霉(Aspergillus niger)CBS 513.88来源的β-甘露聚糖酶同源性最高(67.8%),是一个新型β-甘露聚糖酶。PcMan26A的最适催化条件为pH 6.0和50℃,在pH 4.0~8.0和45℃下具有良好的稳定性。该酶对魔芋粉具有最高的比活力,为3581.0 U/mg。进一步利用该酶水解魔芋粉得到魔芋甘露寡糖,产品得率为86.2%;经分析,其主要组分为聚合度大于4的甘露寡糖。该β-甘露聚糖酶适用于生产魔芋甘露寡糖,为魔芋甘露寡糖的酶法生产提供了更多的选择。 A clonedβ-mannanase(PcMan26A)gene from Penicillium chrysogenum was successfully expressed in Penicillium chrysogenum.At the end of high cell density fermentation,the enzymatic activity of the fermentation supernatant reached 25200 U/mL.The enzyme belonged to the glycoside hydrolase family 26 and shared the highest amino acid sequence identity(67.8%)withβ-mannanase from Aspergillus niger CBS 513.88.The optimal reaction conditions for PcMan26A were pH 6.0 and 50℃,and it was stable at 45℃and within a broad pH range of 4.0–8.0.The enzyme showed the highest specific activity(3581.0 U/mg)towards konjac powder.Furthermore,PcMan26A was used for konjac powder hydrolysis,yielding konjac manno-oligosaccharide with a yield of 86.2%.The main composition of the konjac mannooligosaccharide was manno-oligosaccharides with degree of polymerization>4.The recombinantβ-mannanase provides a new option for the enzymatic production of konjac manno-oligosaccharide.
出处 《食品科学》 EI CAS CSCD 北大核心 2021年第8期98-105,共8页 Food Science
基金 国家自然科学基金青年科学基金项目(31901627) 中国博士后科学基金面上项目(2018M641539)。
关键词 产黄青霉 Β-甘露聚糖酶 毕赤酵母 魔芋粉 甘露寡糖 Penicillium chrysogenum β-mannanase Pichia pastoris konjac powder manno-oligosaccharide
分类号 Q814 [生物学—生物工程]
