Table 5.
Comparison of known essential human nutrients with corresponding biosynthetic pathways in MetaCyc and in HumanCyc
| Essential nutrient in humans | Biosynthetic pathway in MetaCyc? | Biosynthetic pathway inferred in humans? |
| Amino acids | ||
| Arginine | Y | N |
| Histidine | Y | N |
| Isoleucine | Y | N |
| Leucine | Y | N |
| Lysine | Y | N |
| Methionine | Y | N |
| Phenylalanine | Y | N |
| Threonine | Y | N |
| Valine | Y | N |
| Vitamins | ||
| Ascorbic acid (Vitamin C) | Y | N |
| Biotin (Vitamin H) | Y | N |
| Folic acid (Vitamin M) | Y | N |
| Niacin (Vitamin B3) | N | N |
| Pantothenic acid | Y | Y |
| Pyridoxine (Vitamin B6) | N | N |
| Riboflavin (Vitamin B2) | Y | N |
| Thiamine (Vitamin B1) | Y | N |
| Cobalamin (Vitamin B12) | Y | N |
| Retinol (Vitamin A) | N | N |
| Vitamin D | N | N |
| Tocopherol (Vitamin E) | N | N |
| Vitamin K | N | N |
Note that a pathway cannot be predicted in HumanCyc if it does not exist in MetaCyc.