A new engineering strain, Bacillus pumilus c172-14 (pBX 96), was obtained by introducing the pBX 96 plasmid, which carries the α-amylase amy gene, into the host strain of alkalophilic Bacillus pumilus c172 via transformation. The newly constructed strain was found to express the amy gene and could use starch instead of glucose or starch hydrolysate as carbon source for its fermentation of alkaline protease. The pBX 96 plasmid in the new host was found to be segregationally and structurally stable. The expression of amy gene did not affect the host strain's resistance to bacteriophages. Moreover, the level of alkaline protease was improved significantly compared with the parent strain. The constructed strain gave a maximum alkaline protease activity of 14, 014U/ml in shaking flask after 48h cultivation when growing in a medium containing 6% corn meal, 4% soybean flour, 0.4% Na2HPO4, 0.03% KH2PO4, 0.02% MgCl2, 0.3% CaCl2, 0.25% Na2CO3, 0.1% glucose, and 20μg/ml kanamycin (pH 7.0). The optimal pH value and temperature of the alkaline protease were 11.0 and 40℃, respectively. This enzyme was stable over a pH range of 8-11. Its residual activity remained at 100% when treated under a temperature of less than 45℃ for 30min. The corresponding residual activity reduced to 65% of its optimal value at 60℃ for 30min. The alkaline protease was a kind of serine protease, which was demonstrated by the complete inactivation by PMSF (1mM). This newly constructed strain will be useful in the alkaline protease industry.

以5, 5'-二硫硝基苯甲酸（DTNB）为柱前衍生试剂对酶促反应液进行衍生化，用C18色谱柱在室温下采用二元梯度洗脱，于330nm波长下检测，同时以2-巯基乙醇和二硫苏糖醇（DTT）为对照，对L-半胱氨酸的分离峰进行确认，并对酶促反应液中的L-半胱氨酸进行分离测定。L-半胱氨酸浓度为5～950μmol/L时，其浓度与峰面积呈显著的线性关系。高、中、低浓度水平的L-半胱氨酸加标回收率为99.7%～100.5%，相对标准偏差小于1.3%，检测限为0.8μmol/L。方法简便、快速、可靠。用于样品分析，结果令人满意。

地衣芽孢杆菌（Bacillus licheniformis）NK-27菌株发酵产生的β-甘露聚糖酶（β-mannanase）经硫酸铵盐析沉淀，两次DEAE纤维素和Sephadex G-100离子交换柱层析以及制备PAGE等步骤，获得了凝胶电泳均一的样品。用SDS-凝胶电泳测得纯化后的β-甘露聚糖酶分子量为26kD，用凝胶聚焦电泳测得等电点PI为5.0。酶反应的最适pH为9.0，最适温度为60℃，稳定pH为6.0-9.0，稳定温度为40℃。金属离子中Mg2+、Ca2+、Fe2+、Fe2+、Ni2+对该酶有一定的激活作用；而Sn2+、Zn2+、Al3+、Ag+和Hg2+对该酶有强烈的抑制作用。NK-27菌株的β-甘露聚糖酶对魔芋葡萄甘露聚糖和角豆胶半乳甘露聚糖的Km值分别为7.14和5.56mg·ml-1；Vmax分别为200.53和157.45μmol·mg-1·min-1。

从土样中分离筛选出产β-甘露聚糖酶的地衣芽孢杆菌，经紫外线诱变处理后（15W，30cm照射10s）获得高酶活力NK-27菌珠，在以魔芋粉、豆饼粉为碳、氮原添加无机盐的发酵培养基中，β-甘露聚糖酶活力达110.49μ/ml。初始pH值、装液量、培养温度和培养时间对产酶有一定影响。

自70年代开始，国内曾筛选出短小芽孢杆菌（Bacillus pumilus）289、209两株产碱性蛋白酶的菌株。由于这两个菌株以葡萄糖为速效碳源，菌株产碱性蛋白酶的能力受培养基中总糖的制约，且两株菌易受短小芽孢杆菌烈性噬菌体PP1-PP10的感染，因而不利于作为碱性蛋白酶制剂生产用菌。作者已从制革厂毛泥池中分离得到一株碱性蛋白酶产生菌——短小芽孢杆菌c172，该菌株对PP1-PP10噬菌体不敏感，对地衣芽孢杆菌pL1噬菌体亦无交叉感染，是野生型的噬菌体抗性菌株[1]。c172菌无淀粉酶基因，仍以葡萄糖为碳源。为解除培养基中总糖含量对c172菌株产碱性蛋白酶的不利影响，采用原生质体转化手段将带有淀粉酶（Amy）、卡那霉素抗性（Kmr）和氯霉素抗性（Cmr）基因的pBX 96质粒导入c172菌株中，获得了c172（pBX 96）转化子。该转化子能够以玉米粉为碳源，经Amy基因编码的糖化型α-淀粉酶水解玉米粉后，水解物可为菌体生长和生产碱性蛋白酶持续提供碳源。本文报道c172（pBX 96）转化子碱性蛋白酶发酵条件的研究结果。