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Updated: Jun 26, 2025
05:57
Author Spotlight: In Silico Creation and Impact of Carbonylated Amino Acids on Protein Structure and Function
Published on: April 26, 2024
371
Reactive Force Field Molecular Dynamics Investigation of NH3 Generation Mechanism during Protein Pyrolysis Process.
Shuai Guo1,2, Yu Wang1, Shujun Zhu2
1School of Energy and Power Engineering, Northeast Electric Power University, Jilin 132012, China.
Molecules (Basel, Switzerland)
|May 11, 2024
Summary
Ammonia (NH3) is the main product of protein pyrolysis, but its yield decreases at high temperatures. Proteins yield less NH3 than assembled amino acids due to structural differences affecting nitrogen release.
Area of Science:
- Biomass Pyrolysis
- Chemical Engineering
- Computational Chemistry
Background:
- The mechanism of ammonia formation during biomass pyrolysis is not fully understood.
- Proteins are key nitrogen sources in biomass, influencing pyrolysis product distribution.
Purpose of the Study:
- To elucidate the nitrogen transformation and ammonia (NH3) generation mechanisms during protein pyrolysis.
- To compare ammonia formation from actual proteins versus assembled amino acids.
Main Methods:
- Utilized AMS 2023.104 software for model compound selection.
- Performed ReaxFF molecular dynamics simulations.
- Investigated nitrogen transformation in char, tar, and gas phases.
Main Results:
- Ammonia (NH3) is the primary nitrogen product in both protein and amino acid pyrolysis.
- At higher temperatures (2000-2500 K), NH3 decomposes into HCN and N2.
- Pyrolysis of assembled amino acids yielded twice the NH3 compared to actual proteins at 2000 K.
Conclusions:
- Structural differences between proteins and amino acids significantly impact NH3 formation pathways.
- Proteins' shielded nitrogen structures require more energy for NH3 release compared to amino acids' deamination.
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