Pathway · 2 proteins
Biosynthesis of various nucleotide sugars
Proteins of this group that KEGG places on its “Biosynthesis of various nucleotide sugars” map for Aquifex aeolicus.
How it works
This map covers activated sugars used on the cell surface. The proteins here make KDO and ADP-heptose, the sugars of the inner core of lipopolysaccharide, and GDP-linked sugars derived from mannose.
Grouped by KEGG pathway map. The explanation above is the atlas’s own; the map itself covers more organisms than Aquifex.
Its proteins
| Protein | EC | Reaction (UniProt) | Metal or cluster | Amino acids | Certainty |
|---|---|---|---|---|---|
| 2-dehydro-3-deoxyphosphooctonate aldolase | 2.5.1.55 | D-arabinose 5-phosphate + phosphoenolpyruvate + H2O = 3-deoxy-alpha-D-manno-2-octulosonate-8-phosphate + phosphate | — | 267 | Step named |
| 3-deoxy-manno-octulosonate cytidylyltransferase | 2.7.7.38 | 3-deoxy-alpha-D-manno-oct-2-ulosonate + CTP = CMP-3-deoxy-beta-D-manno-octulosonate + diphosphate | — | 234 | Step named |
Origins
How could the activated sugars used to build the cell surface have been made before these enzymes?
None of the books searched discusses a prebiotic route to nucleotide-activated sugars.
The cell builds surface sugars only from sugars activated on a nucleotide carrier, so making them depends on nucleotide supply as well as on sugar supply.
The wider question for this part of the cell: origins for building and maintaining the membrane.
Sources
- KEGG map aae00541 (enzymes of this organism highlighted)
Other pathways in this group: Glycerolipid assembly · Lipid A and outer envelope · Fatty-acid elongation · Substrate recognition · Terpenoid backbone biosynthesis · Fatty acid biosynthesis · Lipopolysaccharide biosynthesis · Not yet placed in a pathway