Method for preparing haemophilus influenza quasi-human-derived carbohydrate chain based on skelemin Fn3

The invention belongs to the field of biotechnology and relates to a method for preparing haemophilus influenza Gal beta 1-4GlcNAc beta 1-3Gal beta 1-3GlcNAc quasi-human-derived carbohydrate chain based on human skelemin Fn3. The method comprises the steps of establishing a recombinant vector suitable for expression of escherichia coli K-12 series strain by comprehensively utilizing a haemophilus influenza lsg gene cluster lipopolysaccharide synthesis mechanism, a campylobacter jejuni pgl gene cluster N-carbohydrate chain synthesis mechanism, an escherichia coli in-vivo O antigen carbohydrate chain synthesis mechanism and a prokaryote transcriptional control mechanism; displaying the quasi-human-derived carbohydrate chain in escherichia coli by means of human-derived skelemin Fn3. The method has the advantages that fusion protein with the quasi-human-derived carbohydrate chain can be prepared easily, quickly and efficiently, and a foundation is provided for efficient low-cost large-scale preparation of quasi-