Human blood group antigen P1 pentasaccharide synthesis method

Abstract

The invention discloses a human blood group antigen P1 pentasaccharide synthesis method. The method includes steps: adopting a one-pot multienzyme system for coupling galactose to trisaccharide as shown in a formula (III) through a beta1-4 glucosidic bond to synthesize tetrasaccharide as shown in a formula (IV); adopting the one-pot multienzyme system for coupling galactose to the tetrasaccharide as shown in the formula (IV) through an alpha1-4 glucosidic bond to synthesize pentasaccharide as shown in a formula (I), wherein in the formula (I), the formula (III) and the formula (IV), R1 refers to hydroxyl, azide substituted alkyl, alkynyl substituted alkyl, sulfydryl substituted alkyl, alpha- or beta- configuration substituted alkyl, alpha- or beta- configuration serine residue and alpha- or beta- configuration threonine residue. By integration of high regioselectivity and high efficiency of enzymatic synthesis, P1 antigen pentasaccharide is synthesized for the first time. Glycosyltransferase, glucose nucleoside generating enzymes and glucokinse adopted in the synthesis method are all derived from prokaryotes, and high protein expression quantity, high substrate adaptability and high catalytic efficiency are realized.

Description

technical field [0001] The invention relates to a synthesis method of carbohydrate substances, in particular to a synthesis method of human blood group antigen P1 pentasaccharide. Background technique [0002] At present, 30 blood group systems have been discovered and recognized by the International Society of Blood Transfusion, and the common blood group systems are ABO blood group system and Rh blood group system. In 1927, Landsteiner and Levine discovered the P Blood Group System (P Blood Group System), and subsequent studies by Morgan and Watkins revealed that its antigenic determinant was the trisaccharide structure Galα(l-4)Galβ(l-4)GlcNAc (such as figure 1 shown). In 1974, scientists such as Naiki and Marcus found that P, P K (Such as figure 2 shown) and P1 antigen exist in human red blood cells and other cells in the form of glycolipids, and the complete structure of P1 antigen is analyzed as pentasaccharide Galα(l-4)Galβ(l-4)GlcNAcβ(l-3)Galβ( l-4) Glc (such as...

AI Technical Summary

Problems solved by technology

For chemical synthesis, due to the inherently active polyhydroxy structure of the P1 antigen pentasaccharide itself, cumbersome protection and deprotection steps are required to ensure regio and stereoselectivity during the synthesis process, resulting in many reaction steps and low overall yield. Low

[0007] The classic method of synthesizing complex oligosaccharides with a one-pot multi-enzyme system can overcome the shortcomings of chemical synthesis methods. However, from the perspective of the source of enzymes and practical applications, the enzymes used to synthesize oligosaccharide chains are mainly divided into two categories: one The first is glycosidase, which has low catalytic synthesis efficiency and wide substrate adaptability; the second is glycosyltransferase, which has high catalytic efficiency and strict substrate selectivity

Glycosidases have been used in industry due to their abundant sources, stable performance, simple reaction, and strong substrate adaptability. However, the yield of oligosaccharide synthesis catalyzed by this type of enzyme is not good.

In addition, due to the low regioselectivity of the transglycosylation reaction catalyzed by glycosidase, and the competition of hydrolysis reaction in the synthesis reaction, the product is uneven- and difficult to separate and purify, which limits its wide application.

There are also many limiting factors in the use of natural glycosyltransferases: the source of enzymes is limited; the instability and complexity of enzymes lead to difficulties in separation and purification; the glycosylation reaction catalyzed by enzymes requires expensive nucleoside activated sugars as glycosyl Donor; enzymes have strict substrate specificity and are less tolerant to unnatural or unusual substrates

The above shortcomings greatly limit the application of glycosidases and glycosyltransferases in the synthesis of complex oligosaccharides in a one-pot multi-enzyme system

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