In this work we are proposing Homology modeled structures of Mycobacterium leprae 18kDa heat shock
protein and its mutant. The more closely related structure of the small heat shock protein (sHSP) belonging to the eukaryotic
species from wheat sHSP16.9 and 16.3kDa ACR1 protein from Mycobacterium tuberculosis were used as template
structures. Each model contains an N-terminal domain, alpha-crystalline domain and a C-terminal tail. The models showed that a
single point mutation from serine to proline at 52nd position causes structural changes. The structural changes are
observed in N-terminal region and alpha-crystalline domains. Serine in 52nd position is observed in β4 strand
and Proline in 52nd position is observed in loop. The number of residues contributing α helix at N-terminal
region varies in both models. In 18S more number of residues is present in α helix when compared to 18P. The loop
regions between β3 and β4 strands of both models vary in number of residues present in it. Number of residues
contributing β4 strand in both models vary. β6 strand is absent in both models. Major functional peptide region
of alpha crystalline domains of both models varies. These differences observed in secondary structures support their distinct
functional roles. It also emphasizes that a point mutation can cause structural variation
