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Quantification of Site-specific Protein Lysine Acetylation and Succinylation Stoichiometry Using Data-independent Acquisition Mass Spectrometry
Published on: April 4, 2018
Lysine requirement through the human life cycle
1INRA, AgroParisTech, UMR914 Nutrition Physiology and Ingestive Behaviour, F-75005 Paris, France. tome@agroparistech.fr
The Journal of Nutrition
|May 22, 2007
Summary
Lysine is an essential amino acid vital for protein synthesis, with significant liver metabolism. Understanding its requirement involves considering microbial contributions and dietary intake across different age groups.
Area of Science:
- Biochemistry
- Nutritional Science
- Mammalian Physiology
Background:
- Lysine is an indispensable amino acid for mammals, crucial for protein synthesis.
- Mammals cannot synthesize lysine, necessitating dietary intake.
- Lysine undergoes substantial first-pass metabolism in the liver (30-42% in humans and piglets).
Purpose of the Study:
- To explore the biological basis of lysine requirements.
- To investigate the potential role of microbial de novo synthesized amino acids in whole-body lysine fluxes.
- To review current lysine intake recommendations and dietary levels.
Main Methods:
- Literature review on lysine metabolism and requirements.
- Analysis of existing data on lysine first-pass metabolism.
- Examination of dietary intake studies and recommendations.
Main Results:
- Lysine is essential for protein synthesis and primarily metabolized in the liver.
- Significant first-pass metabolism of dietary lysine occurs in humans and piglets.
- Lysine requirements vary by age, with recommendations ranging from 30 to 64 mg/(kg·d).
- Western human diets typically provide 40-180 mg/(kg·d) of lysine, with an upper limit of 300-400 mg/(kg·d).
Conclusions:
- Lysine's indispensability and role in protein synthesis are well-established.
- Hepatic first-pass metabolism significantly impacts lysine bioavailability.
- Further research is needed to clarify the contribution of microbial amino acid synthesis to whole-body lysine homeostasis.
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