Amino Acid Synthesis

59 enzymes

CO2 and H2O

17 enzymes

Glucose

Cysteine

Vitamin B6

Cysteine

Liver failure

Intracellular protection against oxidative stress

Inflammation/Infection

The theory implies that essential amino acids are more important for survival, as they are expensive to synthesize and the body needs to rely on obtaining them from the diet. This prioritization ensures that the body maintains the capacity to synthesize essential amino acids, which are crucial for survival.

De novo synthesis refers to the process of synthesizing complex molecules from simple precursors. In amino acid metabolism, de novo synthesis plays a crucial role in producing non-essential amino acids from precursor molecules, ensuring a constant supply of these amino acids for various biological functions.

The process involves using a tracer that is infused and mixes in the precursor pool. By measuring the incorporation of the label from the tracer into individual proteins over several hours, the synthesis of different proteins for different special products can be assessed. This allows for the determination of the rates of synthesis for specific proteins in the body.

High flux rates and de novo synthesis are significant in providing a high proportion of dispensable amino acids, with up to 8% of the basal metabolic rate being accounted for by synthesis. The ultimate precursor for this synthesis is glucose, contributing to the availability of these amino acids.

The S in cysteine is derived from methionine through demethylation. This relationship highlights the interconnectedness of amino acid synthesis and the utilization of precursor amino acids.

B vitamins, including B6, folate, B12, riboflavin, and niacin, play important roles in various aspects of amino acid catabolism and energy metabolism. For example, B6 is required for transamination reactions, folate and B12 are involved in methyl group transfers, and riboflavin and niacin contribute to important metabolic processes.

Glutathione, composed of γ-glutamyl-cysteinyl-glycine, serves as an intracellular protector against oxidative stress and functions as an antioxidant. It plays a crucial role in conjugating with electrophiles, removing reactive oxygen species, glutathionylating proteins, and supporting various cellular functions.

Healthy liver function is essential for proper sulfur amino acid metabolism, as some vitamin deficiencies, such as B6, can significantly impact the synthesis and stability of sulfur amino acids. Liver failure and vitamin deficiencies can disrupt the metabolic pathways and lead to imbalances in amino acid production.

Glutathione depletion can have detrimental effects on various cellular functions, particularly in situations such as burns, AIDS, and inflammation/infection. Correcting glutathione depletion often involves additional protein intake to support the synthesis and maintenance of glutathione levels.

Short-term fasting and protein deficiency can lead to reduced synthesis of dispensable amino acids, impacting overall amino acid availability. These conditions can affect metabolic processes and contribute to imbalances in amino acid levels.