Acta Phys. -Chim. Sin. ›› 2015, Vol. 31 ›› Issue (2): 384-392.doi: 10.3866/PKU.WHXB201412161

• BIOPHYSICAL CHEMISTRY • Previous Articles    

Conformational Change Characteristics in the Intrinsically Disordered FlgM Protein from a Hyperthermophile at Two Different Temperatures

ZHU Yu-Feng1,2,3, CAO Zan-Xia2,3, ZHAO Li-Ling2,3, WANG Ji-Hua2,3   

  1. 1. Department of Physics and Electronic Science, Shandong Normal University, Jinan 250014, P. R. China;
    2. Shandong Province Key Laboratory of Biophysics for Functional Macromolecules, Dezhou 253023, Shandong Province, P. R. China;
    3. Institute of Biophysics, Dezhou University, Dezhou 253023, Shandong Province, P. R. China
  • Received:2014-09-15 Revised:2014-12-16 Published:2015-01-26
  • Contact: WANG Ji-Hua E-mail:jhw25336@126.com
  • Supported by:

    The project was supported by the National Natural Science Foundation of China (61271378, 31000324).

Abstract:

The aim of this work was to compare the structural characteristics of the FlgM protein from the thermophile aquifex aeolicus at room temperature (293 K) and at the physiological temperature (358 K) using molecular dynamics simulations. Two independent long-time molecular dynamics simulations were performed using the GROMACS software package at 293 and 358 K, respectively. The OPLS-AA force field and the TIP3P water model were used. Each simulation was run for 1500 ns. We mainly analyzed the secondary structural characteristics, the overall conformation variation, the conformational characteristics of a semi-disordered region and the structured region of the FlgM protein at two different temperatures. The results indicate that the helix structure of the N terminal increased at room temperature. The FlgM protein had the following characteristics at the physiological temperature: the structure loosed, the helix structure reduced in size, the conformational stability weakened, the H1 helix spread, the conformational flexibility increased, and the degree of instability increased. In summary, the semi-disordered region (N terminal) formed a helical structure in the unbound state and its stability decreased with an increase in temperature. The FlgM protein adapts to temperature by increasing the degree of disorder, creating a more flexible structure by improving the binding rate.

Key words: FlgM protein, Intrinsically disordered protein, Molecular dynamics simulation, Temperature adapting, Structure characteristic

MSC2000: 

  • O643