Pyrimidine Biosynthesis

Structural diagram of the reactions for the synthesis of Dihydroorotate from glutamine and bicarbonate

 

Structural diagram of the reaction catalysed by dihydroorotate DH

 

Structural diagram of the reactions of Orotate phosphorybosyl transferase and OMP decarboxylase

 

Structural diagram of the reaction onverting UTP to CTP

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Regulation of Pyrimidine Biosynthesis

Flow diagram for pyrimidine biosynthesis with feedback control loops for mammals

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Structural diagram of the reactions of teh Purine Nucleotide Cycle

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Purine Degredation Pathway with Structural diagrams of Intermediates and notes showing products

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Metabolic Integration

Stages of Catabolism

Diagram of teh Stages of Metabolism

Note major branch point at pyruvate and the decision point when making acetyl-CoA.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Diagram of the Relationship of Glycolysis to Gluconeogenesis

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Structural Diagram of the Pentose Phosphate Pathway

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Diagram of teh reactions of the Pyruvate-Malate Cycle

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Structural Diagram of the Fatty Acid Synthase Reactions

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Table 1: Average Fuel Storage in a "Normal" 65 kg Man*
Tissue Total amount of fuel Estimated duration of fuel reserve hours (days)
  g kJ Starvation walking running (long distance)
 Liver glycogen 90 1500

3.6

(0.15)

1.2

(0.05)

0.31

(0.013)

 Extracellular glucose 20 320

0.72

(0.03)

0.24

(0.01)

0.07

(0.003)

 Adipose fat 9,000 337,000

816

(34)

259

(10.8)

67

(2.79)

 Protein 8,800 150,000

288

(15)

115

(4.8)

31

(1.3)

Muscle glycogen 350 6,000

1.44

(0.6)

4.8

(0.20)

1.2

(0.05)

* Assuming 12% of body weight is fat for normal men (normal women are about 26%)

Data from E. A. Newsholme & A. R. Leach (1983) Biochemistry for the Medical Sciences, John Wiley, NY. p 337.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Table 2: Tissue Fuel Usage in Fed and Fasting States in Humans

 Tissue

Fed 

Fasting
 used released used released
Liver Glucose (stored as glycogen), Amino acids, Fatty acids Fats, Glucose Amino acids, Lactate, Fatty acids, Glycerol Glucose, Ketone bodies
 Kidney  Glucose   Amino acids, Lactate, Fatty acids, Glycerol   Glucose
 Intestine  Glucose, Aspartate & Glutamate, Asparagine & Glutamine Fatty acids, Amino acids other than asx & glx, Carbohydrates     
 Adipose  Glucose     Fatty acids, glycerol 
 Muscle  Glucose (some stored as glycogen), Branched chain amino acids  Lactate, Alanine & Glutamine  Fatty acids, Ketone bodies, Branched chain amino acids  Amino acids other than branched chain, Lactate
 Brain  Glucose  -  Glucose & Ketone bodies  -

© R. Paselk 2008

Last modified 18 February 2008