title: Glyceraldehyde-3-phosphate dehydrogenase is required for efficient repair of cytotoxic DNA lesions in Escherichia coli.
abstract: Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) is a multifunctional protein with diverse biological functions in human cells. In bacteria, moonlighting GAPDH functions have only been described for the secreted protein in pathogens or probiotics. At the intracellular level, we previously reported the interaction of Escherichia coli GAPDH with phosphoglycolate phosphatase, a protein involved in the metabolism of the DNA repair product 2-phosphoglycolate, thus suggesting a putative role of GAPDH in DNA repair processes. Here, we provide evidence that GAPDH is required for the efficient repair of DNA lesions in E. coli. We show that GAPDH-deficient cells are more sensitive to bleomycin or methyl methanesulfonate. In cells challenged with these genotoxic agents, GAPDH deficiency results in reduced cell viability and filamentous growth. In addition, the gapA knockout mutant accumulates a higher number of spontaneous abasic sites and displays higher spontaneous mutation frequencies than the parental strain. Pull-down experiments in different genetic backgrounds show interaction between GAPDH and enzymes of the base excision repair pathway, namely the AP-endonuclease Endo IV and uracil DNA glycosylase. This finding suggests that GAPDH is a component of a protein complex dedicated to the maintenance of genomic DNA integrity. Our results also show interaction of GAPDH with the single-stranded DNA binding protein. This interaction may recruit GAPDH to the repair sites and implicates GAPDH in DNA repair pathways activated by profuse DNA damage, such as homologous recombination or the SOS response.
authors.affiliation: Departament de Bioquímica i Biología Molecular, Institut de Biomedicina de la Universitat de Barcelona, Facultat de Farmàcia, Universitat de Barcelona, E-08028 Barcelona, Spain.
authors.forename: Elaine
authors.initials: E
authors.lastname: Ferreira
authors.affiliation: Departament de Bioquímica i Biología Molecular, Institut de Biomedicina de la Universitat de Barcelona, Facultat de Farmàcia, Universitat de Barcelona, E-08028 Barcelona, Spain.
authors.forename: Rosa
authors.initials: R
authors.lastname: Giménez
authors.affiliation: Departament de Bioquímica i Biología Molecular, Institut de Biomedicina de la Universitat de Barcelona, Facultat de Farmàcia, Universitat de Barcelona, E-08028 Barcelona, Spain.
authors.forename: María Alexandra
authors.initials: MA
authors.lastname: Cañas
authors.affiliation: Departament de Bioquímica i Biología Molecular, Institut de Biomedicina de la Universitat de Barcelona, Facultat de Farmàcia, Universitat de Barcelona, E-08028 Barcelona, Spain.
authors.forename: Laura
authors.initials: L
authors.lastname: Aguilera
authors.affiliation: Departament de Bioquímica i Biología Molecular, Institut de Biomedicina de la Universitat de Barcelona, Facultat de Farmàcia, Universitat de Barcelona, E-08028 Barcelona, Spain.
authors.forename: Juan
authors.initials: J
authors.lastname: Aguilar
authors.affiliation: Departament de Bioquímica i Biología Molecular, Institut de Biomedicina de la Universitat de Barcelona, Facultat de Farmàcia, Universitat de Barcelona, E-08028 Barcelona, Spain.
authors.forename: Josefa
authors.initials: J
authors.lastname: Badia
authors.affiliation: Departament de Bioquímica i Biología Molecular, Institut de Biomedicina de la Universitat de Barcelona, Facultat de Farmàcia, Universitat de Barcelona, E-08028 Barcelona, Spain. Electronic address: lbaldoma@ub.edu.
authors.forename: Laura
authors.initials: L
authors.lastname: Baldomà
mesh_terms: D004260:DNA Repair / Q000235:genetics / Q000502:physiology; D004926:Escherichia coli / Q000201:enzymology* / Q000235:genetics*; D029968:Escherichia coli Proteins / Q000235:genetics / Q000378:metabolism*; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases / Q000235:genetics / Q000378:metabolism*; D051981:Uracil-DNA Glycosidase / Q000235:genetics / Q000378:metabolism
chemical_list: D029968:Escherichia coli Proteins; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases; D051981:Uracil-DNA Glycosidase
keywords: DNA repair; Endonuclease IV; Glyceraldehyde-3-phosphte dehydrogenase; Single-stranded DNA binding protein; Uracil DNA glycosylase