title: The Role of the ydiB Gene, Which Encodes Quinate/Shikimate Dehydrogenase, in the Production of Quinic, Dehydroshikimic and Shikimic Acids in a PTS- Strain of Escherichia coli.
abstract: The culture of engineered Escherichia coli for shikimic acid (SA) production results in the synthesis of quinic acid (QA) and dehydroshikimic acid (DHS), reducing SA yield and impairing downstream processes. The synthesis of QA by quinate/shikimate dehydrogenase (YdiB, ydiB) has been previously proposed; however, the precise role for this enzyme in the production of QA in engineered strains of E. coli for SA production remains unclear. We report the effect of the inactivation or the overexpression of ydiB in E. coli strain PB12.SA22 on SA, QA, and DHS production in batch fermentor cultures. The results showed that the inactivation of ydiB resulted in a 75% decrease in the molar yield of QA and a 6.17% reduction in the yield of QA (mol/mol) relative to SA with respect to the parental strain. The overexpression of ydiB caused a 500% increase in the molar yield of QA and resulted in a 152% increase in QA (mol/mol) relative to SA, with a sharp decrease in SA production. Production of SA, QA, and DHS in parental and derivative ydiB strains suggests that the synthesis of QA results from the reduction of 3-dehydroquinate by YdiB before its conversion to DHS.
authors.affiliation: Departamento de Ingeniería Celular y Biocatálisis, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, Mexico.
authors.forename: Sofía
authors.initials: S
authors.lastname: García
authors.forename: Noemí
authors.initials: N
authors.lastname: Flores
authors.forename: Ramón
authors.initials: R
authors.lastname: De Anda
authors.forename: Georgina
authors.initials: G
authors.lastname: Hernández
authors.forename: Guillermo
authors.initials: G
authors.lastname: Gosset
authors.forename: Francisco
authors.initials: F
authors.lastname: Bolívar
authors.forename: Adelfo
authors.initials: A
authors.lastname: Escalante
mesh_terms: D000429:Alcohol Oxidoreductases / Q000235:genetics / Q000378:metabolism*; D004926:Escherichia coli / Q000201:enzymology* / Q000235:genetics / Q000378:metabolism*; D015870:Gene Expression; D055786:Gene Knockout Techniques; D060847:Metabolic Engineering; D053858:Metabolic Networks and Pathways / Q000235:genetics; D011801:Quinic Acid / Q000378:metabolism*; D012765:Shikimic Acid / Q000031:analogs & derivatives* / Q000378:metabolism*
chemical_list: D011801:Quinic Acid; C096387:3-dehydroshikimate; D012765:Shikimic Acid; D000429:Alcohol Oxidoreductases; C022641:Shikimate dehydrogenase