Mycobacterium tuberculosis tlyA E59Q is Stable Compared to the Native Protein

The causative agent of human tuberculosis disease, mycobacterium tuberculosis (Mtb), infects one-third of the world population. Mycobacterium tuberculosis tlyA is an important protein and the mutation can cause resistance to antibiotics. Understanding the structure-function of mycobacterium tuberculosis tlyA is essential for preventing antibiotic resistance. Structure of Mycobacterium tuberculosis CTD of tlyA structure was solved, whereas its biological functions are not fully understood. Here, we studied tlyA protein by mutational analysis and molecular modelling studies. Further, purified tlyA is found to be very stable compared to the native tlyA and retained its three dimensional structure. In the absence of full length tlyA structure, molecular model was generated by I-Tasser server using tlyA CTD crystal structure as a template. Generated model showed 90% of residues in the allowed region, 7% in additional allowed region and 3% residues in disallowed region. These results reveal Mtb-tlyA NTD is important for its structure and function and E59Q is a critical residue for retaining the N-terminus.