Analysis of salt-bridges in prolyl oligopeptidase from Pyrococcus furiosus and Homo sapiens.

ABSTRACT: Hyper thermophilic archaea not only tolerate high temperature but also operate its biochemical machineries, normally under these conditions. However, the structural signatures in proteins that answer for the hyper thermo-stability relative to its mesophilic homologue remains poorly understood. We present comparative analyses of sequences, structures and salt-bridges of prolyl-oligopeptidase from Pyrococcus furiosus (pfPOP - PDB ID: 5T88) and human (huPOP - PDB ID: 3DDU). A similar level of hydrophobic and hydrophilic residues in pfPOP and huPOP is observed. A low level of interactions between shell-waters and atom-types in pfPOP indicated hyper thermophilic features are negligible. Salt-bridge-forming-residues (sbfrs) are high in pfPOP's core and surface (pfPOP). Increased sbfrs largely indicate specific-electrostatic is important for thermo stability in pfPOP. Four classes of sbfrs are found namely positionally non-conservative (PNCS), conservative (PCS), unchanged (PU) and interchanged (PIC) type of substitutions. PNCS-sbfrs constitutes 28% and it is associated with the topology of pfPOP at high temperature. PCS helps to increase the salt-bridge population. It is also found that PU maintains similar salt-bridges at the active site and other binding sites while PIC abolishes mesophilic patterns.

SUBMITTER: Bandyopadhyay AK 

PROVIDER: S-EPMC6637400 | biostudies-literature | 2019

REPOSITORIES: biostudies-literature