Structural And Functional Characterization Of Cation-Transporting Atpase Of Mycobacterium Tuberculosis CDC 1551 By In Silico Methods
C Kumar, C Anuradha, K Venkateswara Swamy, N Khan
blast, cation-transporting atpase, homology modeling, in silico, modeller, mycobacterium tuberculosis, procheck, what if
C Kumar, C Anuradha, K Venkateswara Swamy, N Khan. Structural And Functional Characterization Of Cation-Transporting Atpase Of Mycobacterium Tuberculosis CDC 1551 By In Silico Methods. The Internet Journal of Genomics and Proteomics. 2005 Volume 2 Number 1.
The three dimensional (3-D) structure of cation-transporting ATPase (ctATPase) of
With it's re-emergence, tuberculosis (TB) has become a major health problem worldwide and now a days it became a global emergency. It causes nearly 3 million deaths annually and an estimated 8.8 million new cases are reported every year.
The ctATPase of
Most functional restraints on evolutionary divergence operate at the level of tertiary structure hence 3-D structures are more conserved in evolution than sequence . The 3D structure of protein is an important source of information to better understand the function of a protein, its interactions with other compounds (ligands, proteins, DNA) and to understand phenotypical effects of mutations . A large number of techniques have been developed to predict 3-D structures of proteins among which homology modeling is one of the best . Homology modeling is historically the first  and MODELLER has been considered as most accurate method . Hence in the present study also we used homology modeling using MODELLER to generate the 3-D structure of ctATPase. The 3-D structure of ctATPase in
The predicted secondary structure of ctATPase obtained from WHAT IF server (Table 1) clearly indicated the sequence positions of different turns (79), helices (30) and sheets (28). Tentatively ctATPase structure was verified at PROCECK (Table 2) and correspondingly Ramachandran plot (Figure 2) was also constructed to validate the structure .
The function of a protein is generally determined by shape, dynamics and physiochemical properties of its solvent exposed molecular surface. Likewise functional differences among the members of the same protein family are usually a consequence of the structural differences on the protein surface [11, 12]. Hence the functional domains of ctATPase were established through Pfam server and PRODOM and the results clearly revealed three major domains namely HMA (18-79 amino acids), E1-E2-ATPase (215-436 amino acids), and hydrolase (440-667 amino acids) which are responsible for heavy metal binding, phosphorylation activity and hydrolase activity of the protein respectively (Figure 3, Figure 4 and Table 3).
Iron transport by ctATPase in
Authors are grateful to Prof. A. Sali, California Institute for Quantitative Biomedical Research, University of California, San Francisco, for permission to use MODELLER6V2. SKC thanks to UGC-New Delhi for financial support to establish computer networking Lab.