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• BamA, a two-domain OMP with a 16-stranded barrel, harbor L4 as the longest loop. • The designed antigen consisted of 478 aa showed antigen probability of 0.7793. • The novel antigen could elicit protective antibodies against BamA, OmpA and Omp34. • No identical peptides were found in the human proteome for the novel antigen. • The designed construct was safe in regard to allergenicity and toxicity. Acinetobacter baumannii , is among the highest priority bacteria according to the WHO categorization which necessitate the exploration of alternative strategies such as vaccination. OmpA, BamA, and Omp34 are assigned as appropriate antigens to serve in vaccine development against this pathogen. Experimentally validated exposed epitopes of OmpA and Omp34 along with selected exposed epitopes predicted by an integrative in silico approach were represented by the barrel domain of BamA as a scaffold. Among the 8 external loops of BamA, 5 loops were replaced with selected loops of OmpA and Omp34. The designed antigen was analyzed regarding the physicochemical properties, antigenicity, epitope retrieval, topology, structure, and safety. BamA is a two-domain OMP with a 16-stranded barrel in which L4, L6, and L7 were the longest loops of BamA in order. The designed antigen consisted of 478 amino acids with antigen probability of 0.7793. The novel antigen was a 16-stranded barrel. No identical 8-meric peptides were found in the human proteome against the designed antigen sequence. The designed construct was safe regarding the allergenicity, toxicity, and human proteome reactivity. The designed antigen could develop higher protection against A. baumannii in comparison to either OmpA, BamA, or Omp34 alone. [ABSTRACT FROM AUTHOR]

Background and Objectives: Immunization is a promising strategy to combat against the life-threatening infections by Multi Drug Resistance Acinetobacter baumannii. In this study, we directed to design and evaluate the efficacy of a recombinant multi-epitope protein against this pathogen. Materials and Methods: Epitopes prediction was performed for candidate proteins OmpA and BAM complex (BamA, BamB, BamC, BamD, BamE) from A. baumannii, using immune-informatics tools with high affinity for the human HLA alleles. After expression and purification of the recombinant protein, its functional activity was confirmed by interaction with positive sera. Results: Cloning and expression of the desired multi-epitopes protein were verified. Circular Dichroism study showed the secondary structure and proper refolding of the recombinant protein was achieved and matched with computational prediction. There was a significant interaction between designed protein with antibodies presented in ICU patients' and staff's sera. Conclusion: The interaction of the recombinant protein with patients' sera antibodies suggests that it may be a promising determinant protein for immunization against of MDR A. baumannii. [ABSTRACT FROM AUTHOR]

The article presents a study which evaluates the concordance of cervical and rectal Chlamydia trachomatis outer membrane protein (OmpA) genotypes that infects women in Birmingham, Alabama. It states that 22 infected women were the subjects of the study, in which genital specimens were collected. The study shows that majority of the subjects with rectal chlamydial infection had concomitant cervical chlamydial infection and the discordance in rectal and cervical C. trachomatis OmpA was common.