Reversion of mutations in a live mycoplasma vaccine alters its metabolism

• Published in: Vaccine 2023-05, Vol.41 (21), p.3358-3366
• Main Authors: Klose, Sara M., De Souza, David P., Disint, Jillian F., Andrews, Daniel M., Underwood, Gregory J., Morrow, Chris J., Marenda, Marc S., Noormohammadi, Amir H.
• Format: Article
• Language: English
• Subjects: Amino acids; Animals; Arginine deiminase; Bacteria; Chickens; Fitness; GAPDH; Genes; Genetic engineering; Genomes; Genomic analysis; Glyceraldehyde-3-phosphate dehydrogenase; Gram-positive bacteria; Growth kinetics; Immunization; Immunogenicity; Metabolism; Metabolites; Metabolomics; Mutagenesis; Mutation; Mycoplasma; Mycoplasma Infections - veterinary; Mycoplasma synoviae - genetics; N-Methyl-N'-nitro-N-nitrosoguanidine; Nucleotides; ObgE; OppF; Organisms; Pathogens; Peptides; Poultry; Poultry Diseases - prevention & control; Proteins; Reproductive fitness; Reversion; Sequence analysis; Single-nucleotide polymorphism; Software; Statistical analysis; Steady state; Vaccines; Vaccines, Attenuated - genetics
• ISSN: 0264-410X; 1873-2518
• DOI: 10.1016/j.vaccine.2023.04.045

•ObgE plays a role in cell proliferation of Mycoplasma synoviae.•Metabolic alterations in a live M. synoviae vaccine, MS-H, impact attenuation.•OppF is involved in amino acid and/or peptide uptake of M. synoviae.•Enzymatic function of GAPDH in glycolysis is unaffected in MS-H.•Arginine can be utilised to compensate for constrained energy production in MS-H. The live attenuated temperature sensitive vaccine strain MS-H (Vaxsafe® MS, Bioproperties Pty. Ltd., Australia) is widely used to control disease associated with M. synoviae infection in commercial poultry. MS-H was derived from a field strain (86079/7NS) through N-methyl-N'-nitro-N-nitrosoguanidine (NTG)-induced mutagenesis. Whole genomic sequence analysis of the MS-H and comparison with that of the 86079/7NS have found that MS-H contains 32 single nucleotide polymorphisms (SNPs). Three of these SNPs, found in the obgE, oppF and gapdh genes, have been shown to be prone to reversion under field condition, albeit at a low frequency. Three MS-H reisolates containing the 86079/7NS genotype in obgE (AS2), obgE and oppF (AB1), and obgE, oppF and gapdh (TS4), appeared to be more immunogenic and transmissible compared to MS-H in chickens. To investigate the influence of these reversions in the in vitro fitness of M. synoviae, the growth kinetics and steady state metabolite profiles of the MS-H reisolates, AS2, AB1 and TS4, were compared to those of the vaccine strain. Steady state metabolite profiling of the reisolates showed that changes in ObgE did not significantly influence the metabolism, while changes in OppF was associated with significant alterations in uptake of peptides and/or amino acids into the M. synoviae cell. It was also found that GAPDH plays a role in metabolism of the glycerophospholipids as well as an arginine deiminase (ADI) pathway. This study underscores the role of ObgE, OppF and GAPDH in M. synoviae metabolism, and suggests that the impaired fitness arising from variations in ObgE, OppF and GAPDH contributes to attenuation of MS-H.