Stability of dimeric interface in banana lectin: Insight from molecular dynamics simulations

Area of Science:

• Biochemistry
• Structural Biology
• Molecular Dynamics

Background:

• Banana lectin (Banlec) is a homodimeric, non-glycosylated protein with a beta-prism I structure.
• Understanding protein stability under thermal stress is crucial in molecular biology.

Purpose of the Study:

• To investigate the thermal unfolding of Banana lectin (Banlec) using high-temperature molecular dynamics simulations.
• To elucidate the structural and conformational changes of the Banlec dimer at varying temperatures.

Main Methods:

• High-temperature molecular dynamics simulations were performed at four different temperatures.
• Analysis included radius of gyration, rms deviation, solvent accessibility, and inter/intra-subunit interactions.
• Hydrogen bonding patterns within and between subunits were examined.

Main Results:

• The Banlec dimer demonstrated high stability, primarily due to strong interfacial interactions.
• The overall conformation remained intact at 400-500 K, with increased loop region dynamics.
• At 600 K, tertiary and subsequently secondary structures were progressively lost.

Conclusions:

• Banana lectin exhibits significant intrinsic stability, largely conferred by its interfacial interactions.
• The protein's structural integrity is maintained up to 500 K, with unfolding initiated at higher temperatures.
• Hydrogen bonding patterns provide a rationale for Banlec's remarkable thermal stability.