角蛋白酶基因kerB的提取、克隆及表达

从角蛋白酶产生菌株地衣芽孢杆菌L—25中提取基因组DNA，借助特定引物通过聚合酶链反应(PCR)扩增得到kerB基因片段，扩增后的kerB片段通过分子生物学方法克隆到产酶缺陷型枯草芽孢杆菌DBl04菌株敏感细胞中进行表达。结果表明，表达成功的FD—8菌株(DBl04／pLK18)可以在羽毛培养基上生长并完全水解羽毛。  

羽毛角蛋白酶生产菌的选育及产酶条件研究

从长期堆积废羽毛的土壤中分离筛选出15株对羽毛有降解能力的细菌，然后经过摇瓶复筛得到一株对羽毛有较强降解能力的菌株，该菌内生孢子，革兰氏染色阳性，为一芽孢杆菌，摇瓶发酵的最适条件为：温度42度，pH为7．5，转速125rpm，最高酶活力达25．20U/mL，外加其他碳源或氮源对角蛋白酶的产生有一定的影响。  

枯草芽孢杆菌YYW-1蛋白酶缺陷株诱变与筛选

从羽毛废弃物中筛选出一株高效降解羽毛、产角蛋白酶和蛋白酶的革兰氏阳性芽孢杆菌,经鉴定为枯草芽孢杆菌(Bacillus sublitis),命名为B.sublitisYYW-1。利用紫外线对菌株YYW-1进行诱变,筛选蛋白酶缺陷株,获得蛋白酶活性丧失的诱变株YYW-1-5,其蛋白酶活性残余22.7%,而角蛋白酶活性残余94.7%,没有明显的变化。  

“6·18”中国福建项目交易会的思考

2003年的“6·18”中国福建项目交易会的成功举办促进了项目的对接，福建圣农集团每天有6吨鸡毛一直当废品卖，每100克5分。在交易会上与福州大学百特公司成功实现项目对接，百特的高科技——高效角蛋白酶可将每100克鸡毛水解成近  

高效降解羽毛角蛋白菌株的筛选与鉴定

以羽毛角蛋白作为唯一碳源和氮源,从长期堆积腐烂羽毛的土壤中分离出一株高效降解羽毛角蛋白的菌株.通过对该菌株形态特征观察、生理生化实验测定、16S rDNA序列分析和Biolog系统鉴定,初步鉴定为地衣芽孢杆菌(Bacillus licheniformis),且命名为地衣芽孢杆菌F4.F4在50℃条件下摇瓶发酵48 h,角蛋白酶活达到23 U/mL.该菌能够降解完整的天然羽毛,具有开发应用前景.  

Keratinase production and keratin degradation by a mutant strain of Bacillus subtilis

A new feather-degrading bacterium was isolated from a local feather waste site and identified as Bacillus subtilis based on morphological, physiochemical, and phylogenetic characteristics. Screening for mutants with elevated keratinolytic activity using N-methyl-N＇-nitro-N-nitrosoguanidine mutagenesis resulted in a mutant strain KD-N2 producing keratinolytic activity about 2.5 times that of the wild-type strain. The mutant strain produced inducible keratinase in different substrates of feathers, hair, wool and silk under submerged cultivation. Scanning electron microscopy studies showed the degradation of feathers, hair and silk by the keratinase. The optimal conditions for keratinase production include initial pH of 7.5, inoculum size of 2% （v/v）, age of inoculum of 16 h, and cultivation at 23 ℃. The maximum keratinolytic activity of KD-N2 was achieved after 30 h. Essential amino acids like threonine, valine, methionine as well as ammonia were produced when feathers were used as substrates. Strain KD-N2, therefore, shows great promise of finding potential applications in keratin hydrolysis and keratinase production.  

高效产角蛋白酶芽孢菌株JDBM-1的筛选及鉴定

为了筛选高效降解羽毛角蛋白的芽孢菌株,对菌源样品通过以羽毛粉为唯一碳氮源进行富集培养,以酪蛋白固体平板初筛,测定菌株上清液中角蛋白酶活力并进行酪氨酸含量复筛,同时观察其对完整羽毛的降解速率,筛选到10株产角蛋白酶菌株,其中菌株JDBM-1 72h可将完整羽毛成分降解,角蛋白酶活力为117.39U/mL.综合菌株形态特征、生理生化试验结果和16SrRNA基因序列分析,确定JDBM-1菌株为Bacillus subtilis.