2-keto-L-gulonic acid producing strain and construction method thereof

The invention provides a construction method for a 2-keto-L-gulonic acid producing strain. The method comprises one or more of the following steps in any sequence: 1) interrupting a membrane-bound glucose dehydrogenase coding gene in a chromosome of tetramorium; 2) interrupting a glucokinase coding gene; 3) interrupting a gluconokinase coding gene; 4) interrupting a 2-ketoaldose reductase coding gene and/or isozyme coding gene thereof; 5) carrying out recombinant expression on NAD(P)+ type glucose dehydrogenase; 6) carrying out recombinant expression on the NAD(P)H type 2,5-diketo-D-gluconatereductase; 7) carrying out overexpression on the 2,5-diketo-D-gluconic acid internal transport protein ARU92990 and ARU92994; and 8) interrupting the PTS component coding gene in the cell chromosome to obtain a genetically engineered bacterium. The 2-keto-L-gulonic acid producing strain constructed by the construction method can be used for producing 2-keto-L-gulonic acid by taking glucose as a raw material through a one-