title: Direct cloning and transplanting of large DNA fragments from Escherichia coli chromosome.
abstract: We applied a resistance split-fusion strategy to increase the in vivo direct cloning efficiency mediated by Red recombination. The cat cassette was divided into two parts: cma (which has a homologous sequence with cmb) and cmb, each of which has no resistance separately unless the two parts are fused together. The cmb sequence was integrated into one flank of a target cloning region in the chromosome, and a linear vector containing the cma sequence was electroporated into the cells to directly capture the target region. Based on this strategy, we successfully cloned an approximately 48 kb DNA fragment from the E. coli DH1-Z chromosome with a positive frequency of approximately 80%. Combined with double-strand breakage-stimulated homologous recombination, we applied this strategy to successfully replace the corresponding region of the E. coli DH36 chromosome and knock out four non-essential genomic regions in one step. This strategy could provide a powerful tool for the heterologous expression of microbial natural product biosynthetic pathways for genome assembly and for the functional study of DNA sequences dozens of kilobases in length.
authors.affiliation: Institute of Biotechnology, Academy of Military Medical Sciences, Beijing, 100071, China.|Institute of Life Science and technology, China Pharmaceutical University, Nanjing, 210009, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Zhu
authors.affiliation: Institute of Biotechnology, Academy of Military Medical Sciences, Beijing, 100071, China.|Institute of Life Science and technology, China Pharmaceutical University, Nanjing, 210009, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Yang
authors.affiliation: Institute of Biotechnology, Academy of Military Medical Sciences, Beijing, 100071, China.|Institute of Health Sciences, Anhui University, Hefei, 230039, China.
authors.forename: Pingping
authors.initials: P
authors.lastname: Den
authors.affiliation: Institute of Microbiology and Epidemiology, Academy of Military Medical Sciences, Beijing, 100071, China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Huang
authors.affiliation: Institute of Life Science and technology, China Pharmaceutical University, Nanjing, 210009, China. Nimx_2000@aliyun.com.
authors.forename: Mengxiang
authors.initials: M
authors.lastname: Ni
authors.affiliation: Institute of Biotechnology, Academy of Military Medical Sciences, Beijing, 100071, China. fanghongqing@vip.sina.com.|Institute of Health Sciences, Anhui University, Hefei, 230039, China. fanghongqing@vip.sina.com.
authors.forename: Hongqing
authors.initials: H
authors.lastname: Fang
mesh_terms: D053898:Biosynthetic Pathways / Q000235:genetics; D002876:Chromosomes, Bacterial / Q000235:genetics*; D003001:Cloning, Molecular / Q000379:methods*; D004269:DNA, Bacterial / Q000235:genetics*; D018274:Electroporation; D004926:Escherichia coli / Q000145:classification / Q000235:genetics*; D005818:Genetic Engineering / Q000379:methods; D016680:Genome, Bacterial / Q000235:genetics; D059765:Homologous Recombination; D008957:Models, Genetic; D010957:Plasmids / Q000235:genetics; D015203:Reproducibility of Results; D013045:Species Specificity; D014170:Transformation, Genetic
chemical_list: D004269:DNA, Bacterial
keywords: Red homologous recombination; resistance split-fusion; target cloning; transferring