Functional mechanism of C-terminal tail in the enzymatic role of porcine testicular carbonyl reductase: a combined experiment and molecular dynamics simulation study of the C-terminal tail in the enzymatic role of PTCR

PLoS One. 2014 Mar 19;9(3):e90712. doi: 10.1371/journal.pone.0090712. eCollection 2014.

Abstract

Porcine testicular carbonyl reductase, PTCR which is one of the short chain dehydrogenases/reductases (SDR) superfamily catalyzes the NADPH-dependent reduction of carbonyl compounds including steroids and prostaglandins. Previously we reported C-terminal tail of PTCR was deleted due to a nonsynonymous single nucleotide variation (nsSNV). Here we identified from kinetic studies that the enzymatic properties for 5α-dihydrotestosterone (5α-DHT) were different between wild-type and C-terminal-deleted PTCRs. Compared to wild-type PTCR, C-terminal-deleted PTCR has much higher reduction rate. To investigate structural difference between wild-type and C-terminal-deleted PTCRs upon 5α-DHT binding, we performed molecular dynamics simulations for two complexes. Using trajectories, molecular interactions including hydrogen bonding patterns, distance between 5α-DHT and catalytic Tyr193, and interaction energies are analyzed and compared. During the MD simulation time, the dynamic behavior of C-terminal tail in wild-type PTCR is also examined using essential dynamics analysis. The results of our simulations reveal that the binding conformation of 5α-DHT in C-terminal-deleted PTCR is more favorable for reduction reaction in PTCR, which shows strong agreement with kinetic data. These structural findings provide valuable information to understand substrate specificity of PTCR and further kinetic properties of enzymes belonging to the SDR superfamily.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aldehyde Reductase / chemistry*
  • Aldehyde Reductase / genetics
  • Aldo-Keto Reductases
  • Animals
  • Biocatalysis
  • Catalytic Domain
  • Dihydrotestosterone / chemistry*
  • Escherichia coli / genetics
  • Escherichia coli / metabolism
  • Gene Expression
  • Kinetics
  • Male
  • Molecular Docking Simulation
  • Molecular Dynamics Simulation
  • NADP / chemistry*
  • Oxidation-Reduction
  • Protein Binding
  • Protein Structure, Tertiary
  • Recombinant Fusion Proteins / chemistry*
  • Recombinant Fusion Proteins / genetics
  • Substrate Specificity
  • Swine
  • Testis / chemistry
  • Testis / enzymology
  • Thermodynamics

Substances

  • Recombinant Fusion Proteins
  • Dihydrotestosterone
  • NADP
  • Aldo-Keto Reductases
  • Aldehyde Reductase

Grants and funding

This research was supported by Management of Climate Change Program (2010-0029084), Basic Science Research Program (2011-0024925), and Priority Research Centers Program (2011-0022965) through the National Research Foundation of Korea (NRF) funded by the Ministry of Education of Republic of Korea. And this work was also supported by the Next-Generation BioGreen 21 Program (PJ009486) from Rural Development Administration (RDA) of Republic of Korea. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.