Metabolic engineering of non-pathogenic Escherichia coli strains for the controlled production of low molecular weight heparosan and size-specific heparosan oligosaccharides

Pharmacology of Heparin and Related Drugs: An Update

“…The heparosan starting material is available as a capsular polysaccharide of bacteria, the best known of which is E. coli K5, though other bacteria such as Pasteurella multocida have also been investigated (Na et al, 2020). The bacterial source may itself also be engineered to modify the yield (Nehru et al, 2021) and/or the molecular weight of the resulting heparosan (Roy et al, 2021). It has even been possible to engineer a strain of E. coli to produce both heparosan (secreted) and N-deactylase/N-sulfotransferase (intracellular) simultaneously (Li et al, 2021c).…”

Heparin mimetics as potential intervention for COVID-19 and their bio-manufacturing

“…By up-regulating a single precursor pathway gene UDP and expressing kfiC and kfiA glycosyltransferase genes from E. coli K5, the maximum concentration of heparosan produced by engineering B. megaterium in the bioreactor increased to 394 mg/L, further through fed-batch fermentation, the heparosan titer was increased to 1.32 g/L [ 113 ]. The non-pathogenic E. coli BL21 was also used to express heparosan; by inducing the four essential heparosan biosynthesis genes pKfiA - pKfiD in it and optimizing the cultivation process, heparosan titer reached 1.88 g/L [ 109 ], and when co-express the eliminase gene elmA , heparosan polysaccharide (about 60–100 kDa) can be cleaved into smaller oligosaccharide [ 114 ]. The most effective chassis may be B. subtilis (a recognized safe strain for industrial production), with heparosan titers reaching 5.82 g/L through up-regulation of the tauD gene (encoding the UDPGDH enzyme) and fermentation optimization [ 110 , 115 ].…”

Bacterial glycobiotechnology: A biosynthetic route for the production of biopharmaceutical glycans

“…Low molecular weight heparosan was transferred and cloned into three non-pathogenic E. coli strains: BL21 (DE3), HT115 (DE3), and Shuffle T7 (DE3), by carefully analyzing each host bacteria's growth parameters, such as culture media composition, culture times, and cloning orders. The research team regulated the heparosan chain length range from 150 KDa to 5 KDa (Roy et al, 2021). Thereby, they successfully engineered E.…”