In the CRISPR Cas9 system for gene knockout and targeted insertion in microorganisms, including E. coli, the sacB gene in the Cas9 plasmid helps eliminate the plasmid post-recombination.

Schafer A, et al. Small mobilizable multi-purpose cloning vectors derived from the Escherichia coli plasmids pK18 and pK19: selection of defined deletions in the chromosome of Corynebacterium glutamicum. Gene 145: 69-73, 1994. PubMed: 8045426. xa0Frozen E. coli containing the plasmid. 获得菌株后，原则上应尽早进行活化和保存。 若不能立即活化，应按照说明书放入相应的环境中进行保存。

（1） 以苜蓿中华根瘤菌 Rm1021 基因组 DNA 为模板，通过 PCR 分别扩增出 SmdesA 基因的上下游片段 (Up， Down)，重叠 PCR 将 SmdesA 基因上下游片段连接起来扩增得到 SmdesA (UpDn)，连接到 pMD19-T，送测序。 （2） SmdesA (UpDn) 用限制性内切酶 EcoR Ⅰ和 Hind Ⅲ消化 DNA 片段后，连接到用相应限制性内切酶消化的 pK18mobsacB 载体上，得到 pK18mobsacB-SmdesAUpDn。

pK18mobSacB载体价格1500元，pK18mobSacB载体质粒图谱 (Vector map),载体序列 (Sequence)见下文，载体大小为5.6kb，载体抗性为Kanamycin。 pK18mobSacB是芽孢杆菌基因敲除载体。

克隆载体，允许动员到广泛的革兰氏和革兰氏+细菌。 pK18mob载体价格3800元，pK18mob载体质粒图谱 (Vector map)，载体序列 (Sequence)见下文，载体质粒抗性为卡那，质粒大小为3.8 kb。 pK18mob载体是质粒。

Cloning vector allowing mobilization into a wide range of GramandGram+ bacteria. Aftermobilization, the plasmid can be maintained by integration into the host chromosome viahomologous recombination.

Small mobilizable multi-purpose cloning vectors derived from the Escherichia coli plasmids pK18 and pK19: selection of defined deletions in the chromosome of Corynebacterium glutamicum. Gene 145, 69–73. doi:10.1016/0378-1119 (94)90324-7. These plasmids were created by …

pK18msB载体价格质粒购买价格是1200元，pK18msB载体质粒图谱 (Vector map)，pK18msB (addgene 177839)载体序列 (Sequence)见下文，载体质粒抗性为Kanamyci，质粒大小为3.2 kb，测序引物见下文。 pK18msB载体是细菌表达载体质粒。

New and versatile cloning vectors with kanamycin-resistance marker // Gene. – 1987. – V. 56. – No. 2-3. – P. 309-312. See also pK18mob. A plasmid for cloning of small DNA fragments in E. coli. Sequence verification of the inserted fragment can be performed using M13 sequencing primers. Reference: (PMID: 3315864) Pridmore R. D.

(1) 克隆菌株:DH5α、TOP10、XL1-Blue等均可。 (2) 原核抗性:Kan+ ,工作浓度建议为25ug/ml。 (3) 培养温度:37°C。