The Role of Antibodies against the COML to Combat Acinetobacter baumannii Antibiotic Resistance
Archives of Advances in Biosciences,
Vol. 17 No. 1 (2026),
28 April 2026
,
Page 1-8
https://doi.org/10.22037/aab.v17i1.52191
Abstract
Background: When treating infectious diseases, resistance to antimicrobial medications leads to significant challenges. One of the proteins involved in the transformation of a resistant plasmid is COML, a DNA's absorbent protein. Acinetobacter baumannii's outer membrane contains this protein. The immunogenicity of the COML protein and its function in absorbing plasmids resistant to antibiotics were examined in this study.
Methods: : The comL gene from A. baumannii ATCC 19606 was amplified and cloned into the pET28a expression vector, followed by expression in E. coli BL21 (DE3). Recombinant ComL protein was purified using Ni-NTA affinity chromatography and administered to BALB/c mice to induce a ComL-specific antibody response. The functional effect of immune serum on transformation and the bacterial burden in challenged mice were subsequently evaluated using selective culture and colony-forming unit (CFU) enumeration.
Results: Recombinant ComL was successfully expressed as an approximately 22-kDa protein and induced a significantly higher ComL-specific antibody response in immunized mice than in control mice (P < 0.05). In the in vitro transformation experiment, exposure to immune serum was associated with reduced recovery of antibiotic-resistant colonies under the relevant selective conditions. In the mouse experiments, animals receiving anti-ComL immune responses showed lower recovery of antibiotic-resistant bacteria from the examined tissues than the corresponding control animals.
Conclusion: Immunization with recombinant ComL induces a measurable antibody response and may interfere with ComL-associated natural transformation and the acquisition or recovery of antibiotic-resistant A. baumannii. However, the precise molecular mechanism underlying this effect requires further investigation.
- Recombinant protein
- COML protein
- A baumannii
- Antibiotic resistance
- Immunotherapy
How to Cite
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