Role of the Mycoplasma bovis deoC gene in nucleoside catabolism and host cell survival

ABSTRACT A putative deoC gene (MBOVPG45₀300) is critical for the survival of the important bovine pathogen Mycoplasma bovis in co-culture with Madin-Darby bovine kidney (MDBK) cells. To investigate the function of this gene, combined metabolomic analyses were performed to compare the polar metabolite profiles of a mutant strain with a transposon insertion into the MBOVPG45₀300 gene (∆MBOVPG45₀300) with those of the parent strain PG45. Steady-state metabolomic analysis showed that the ∆MBOVPG45₀300 mutant had significantly lower abundances of metabolites in nucleoside metabolism and significantly higher abundances of intermediates in the pentose phosphate pathway. An isotope labeling study using 13 C 5 -thymidine revealed that deoxyribonucleoside catabolism was disrupted in ∆MBOVPG45₀300 and that the production of acetyl-coenzyme A was affected. Metabolomic footprinting suggested that the disruption of MBOVPG45₀300 resulted in a compensatory increase in uptake of pyruvate. These different metabolomic analyses of the metabolic changes associated with disruption of MBOVPG45₀300 suggested that this gene played a critical role in the catabolism of deoxyribonucleosides in M. bovis. IMPORTANCE Mycoplasmas are reliant on host cells for the acquisition of nutrients, and their metabolic functions are vital for both survival and virulence. Metabolomic analysis can be used to determine the metabolic functions of genes in mycoplasmas by examining the metabolic changes in mutants with gene disruptions. We combined different metabolomic techniques to study the metabolic changes in the important bovine pathogen Mycoplasma bovis caused by the disruption of the putative deoC gene, which is essential for the survival of this organism in association with host cells. Our results suggest the product of the gene plays a role in the catabolism of deoxyribonucleosides and that this metabolic pathway is critically important in the interactions of M. bovis with host cells.