Recombinant Mycoplasma agalactiae Elongation factor Tu (tuf)
Description
Definition and Biological Role
Recombinant Mycoplasma agalactiae Elongation Factor Tu (EF-Tu) is a genetically engineered version of the EF-Tu protein derived from the tuf gene of M. agalactiae, a pathogenic mycoplasma causing contagious agalactia in small ruminants . EF-Tu is a highly conserved GTPase essential for protein synthesis, facilitating the binding of aminoacyl-tRNA to the ribosome . Beyond its canonical role, EF-Tu exhibits moonlighting functions on bacterial surfaces, including adhesion to host cells and immune modulation .
Recombinant EF-Tu is typically expressed in Escherichia coli systems, enabling large-scale production for research. Studies on related mycoplasmas (e.g., Mycoplasma ovipneumoniae) demonstrate that recombinant EF-Tu:
-
Elicits strong IgG and cytokine responses (e.g., IFN-γ, IL-12) in animal models .
-
Serves as a vaccine candidate due to surface exposure and immunogenicity .
For M. agalactiae, EF-Tu’s role in adhesion to host cells (e.g., mammary epithelial cells) has been inferred from knockout mutant studies showing growth deficiencies in cell-culture assays .
Table 2: Growth Deficiency of M. agalactiae EF-Tu Knockout Mutants5
| Host Cell Type | Mutants with Growth Deficiency (%) |
|---|---|
| Goat mammary epithelial | 0.7% |
| Goat embryonic fibroblast | 4.4% |
| HeLa cells | 7.0% |
Diagnostic and Therapeutic Potential
-
Diagnostics: EF-Tu’s high sequence conservation makes it a target for genus-specific PCR primers. For example, tuf-based assays achieve 98–99% specificity in streptococci , a strategy adaptable to M. agalactiae.
-
Therapeutics: In Mycoplasma pneumoniae, EF-Tu binds plasminogen, enabling tissue invasion via plasmin activation . Inhibiting this interaction could mitigate pathogenicity.
Research Gaps and Future Directions
Product Specs
Target Background
KEGG: maa:MAG3200
