Cloning and characterization of the genes coding for antigen 85A, 85B and 85C of Mycobacterium avium subsp....

Area of Science:

• Microbiology
• Molecular Biology
• Genetics

Background:

• The antigen 85 complex is a group of secreted proteins in mycobacteria.
• These proteins play roles in cell wall synthesis and immune response.
• Understanding these proteins in Mycobacterium avium subsp. paratuberculosis is crucial for diagnostics and therapeutics.

Purpose of the Study:

• To clone, sequence, and analyze three antigen 85 genes (A, B, and C) from Mycobacterium avium subsp. paratuberculosis.
• To compare these sequences with those from other mycobacterial species.
• To investigate conserved regions potentially involved in fibronectin binding.

Main Methods:

• Gene cloning and DNA sequencing of antigen 85-A, B, and C.
• Bioinformatic analysis including multiple sequence alignment and homology analysis.
• Identification of conserved protein regions.

Main Results:

• The complete sequences of the three antigen 85 proteins from M. avium subsp. paratuberculosis were determined.
• These sequences exhibited 99% homology with M. avium 85-complex proteins and high similarity to other mycobacterial species.
• Variations were localized to specific amino acid positions across different mycobacterial 85-complex proteins.
• Three conserved regions, known for fibronectin binding in other mycobacteria, were identified in the N-terminal regions of M. avium subsp. paratuberculosis 85A, B, and C.

Conclusions:

• The antigen 85 proteins of M. avium subsp. paratuberculosis share significant sequence homology with their counterparts in other mycobacteria.
• The identified conserved N-terminal regions suggest a conserved function in fibronectin binding across species.
• These findings contribute to understanding the molecular characteristics of M. avium subsp. paratuberculosis and potential targets for intervention.