《高产木聚糖酶菌株的选育的》-毕业论文.doc

PAGE i 毕 业 设 计（论 文） 题 目 高产木聚糖酶菌株的选育 姓 名 王贵娥 学 号 0910511238 所在学院 轻工学部 专业班级 2009 级生物工程2班 指导教师 蔡俊教授 日 期 2013 年6月6日 毕业设计（论文）专用纸 PAGE 6 摘 要 本课题以自制木聚糖样品为唯一碳源，透明圈平板筛选法初筛，摇瓶发酵复筛，从土壤中筛选出五株产木聚糖酶的菌株，其中株菌Q2酶活最高，其酶活为5.858IU/ml。以Q2菌株为出发菌株，酶活力为评价指标，采用单因素的方法对培养条件进行优化，得出最优培养条件为：温度37℃，接种量为6%，种龄16h，初始 pH值8.0。然后以Q2菌株为出发菌株，进行紫外诱变，透明圈平板筛选法初筛，摇瓶发酵复筛，获得突变株T3，酶活达7.54IU/mL，较出发菌株Q2提高了 1.32倍。经遗传稳定性试验，该性状具有一定的遗传稳定性。 关键词：菌种筛选，木聚糖酶，酶活力，紫外诱变 Abstract The topics to sample homemade xylan as sole carbon source, transparent circle plate screening screening, rescreening fermentation, screened from soil xylanase five strains, including strains Q2 highest activity, its enzymatic activity for the 5.858IU/ml. Q2 strain was starting to strain, activity indicators for the evaluation, the use of single-factor approach to culture conditions were optimized, and the optimal culture conditions: temperature 37 ℃, inoculation of 6%, seed age 16h, initial pH 8.0 . Then Q2 strain as the starting strain by UV mutagenesis, transparent circle plate screening screening, rescreening fermentation obtained mutant T3, activity reached 7.54IU/mL, compared with the starting strain Q2 increased 1.32 times. Warp genetic stability test, the trait has a certain genetic stability. Keywords: strain selection, the xylanase enzyme , enzyme activity, IUV mIUtagenesis 目录 TOC \o 1-3 \h \z \u HYPERLINK \l _Toc357618223 摘 要 PAGEREF _Toc357618223 \h I HYPERLINK \l _Toc357618224 Abstract PAGEREF _Toc357618224 \h II HYPERLINK \l _Toc357618225 1 前言 PAGEREF _Toc357618225 \h 1 HYPERLINK \l _Toc357618226 1.1 木聚糖及木聚糖酶的简介 PAGEREF _Toc357618226 \h 1 HYPERLINK \l _Toc357618227 1.1.1 木聚糖的结构及其木聚糖酶的分类 PAGEREF _Toc357618227 \h 1 HYPERLINK \l _Toc357618228 1.1.2 木聚糖酶的分子结构 PAGEREF _Toc357618228 \h 1 HYPERLINK \l _Toc357618229 1.1.3 木聚糖酶的理化性质 PAGEREF _Toc357618229 \h 1 HYPERLINK \l _Toc357618230 1.1.4 木聚糖酶的催化机制 PAGEREF _Toc357618230 \h 2 HYPER