Construction of Monophosphoryl Lipid A Producing Escherichia coli Mutants and Comparison of Immuno-Stimulatory Activities of Their Lipopolysaccharides

Marine Drugs

Yaning Han²  Ye Li²  Jiuzhou Chen²  Yanzhen Tan²  Feng Guan¹ 

[1] Key Laboratory of Carbohydrate Chemistry and Biotechnology of Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China; E-Mail:;State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China; E-Mails:

关键词: lipopolysaccharide;    lipid A;    MPLA;    endotoxin;    vaccineadjuvant;    Escherichia coli;    murine macrophage;   

DOI  :  10.3390/md11020363

来源: mdpi

【 摘 要 】

The lipid A moiety of Escherichia coli lipopolysaccharide is a hexaacylated disaccharide of glucosamine phosphorylated at the 1- and 4′-positions. It can be recognized by the TLR4/MD-2 complex of mammalian immune cells, leading to release of proinflammatory cytokines. The toxicity of lipid A depends on its structure. In this study, two E. coli mutants, HW001 and HW002, were constructed by deleting or integrating key genes related to lipid A biosynthesis in the chromosome of E. coli W3110. HW001 was constructed by deleting lacI and replacing lacZ with the Francisellanovicida lpxE gene in the chromosome and only synthesizes monophosphoryl lipid A. HW002 was constructed by deleting lpxM in HW001 and synthesizes only the pentaacylated monophosphoryl lipid A. The structures of lipid A made in HW001 and HW002 were confirmed by thin layer chromatography and electrospray ionization mass spectrometry. HW001 and HW002 grew as well as the wild-type W3110. LPS purified from HW001 or HW002 was used to stimulate murine macrophage RAW264.7 cells, and less TNF-α were released. This study provides a feasible way to produce interesting lipid A species in E. coli.

【 授权许可】

CC BY   
© 2013 by the authors; licensee MDPI, Basel, Switzerland.