Overview: Asparagine biosynthesis in GapMind is based on MetaCyc pathways L-asparagine biosynthesis I (link), II (link), or III (tRNA-dependent) (link). In pathways I or II, aspartate is amidated directly, with glutamine or ammonia as the nitrogen source. In pathway III, aspartate is ligated to tRNA(Asn) and then amidated to Asn-tRNA(Asn).
Or see definitions of steps
Step | Description | Best candidate | 2nd candidate |
---|---|---|---|
aspS2 | aspartyl-tRNA(Asp/Asn) synthetase | EUBREC_RS13125 | EUBREC_RS05210 |
gatA | aspartyl/glutamyl-tRNA(Asn/Gln) amidotransferase subunit A | EUBREC_RS05220 | |
gatB | aspartyl/glutamyl-tRNA(Asn/Gln) amidotransferase subunit B | EUBREC_RS05225 | |
gatC | aspartyl/glutamyl-tRNA(Asn/Gln) amidotransferase subunit C | EUBREC_RS18280 | |
Alternative steps: | |||
asnA | aspartate--ammonia ligase | EUBREC_RS06015 | |
asnB | asparagine synthase (glutamine-hydrolysing) | EUBREC_RS00660 |
Confidence: high confidence medium confidence low confidence
? – known gap: despite the lack of a good candidate for this step, this organism (or a related organism) performs the pathway
This GapMind analysis is from Aug 01 2024. The underlying query database was built on Jul 25 2024.
Each pathway is defined by a set of rules based on individual steps or genes. Candidates for each step are identified by using ublast (a fast alternative to protein BLAST) against a database of manually-curated proteins (most of which are experimentally characterized) or by using HMMer with enzyme models (usually from TIGRFam). Ublast hits may be split across two different proteins.
A candidate for a step is "high confidence" if either:
Otherwise, a candidate is "medium confidence" if either:
Other blast hits with at least 50% coverage are "low confidence."
Steps with no high- or medium-confidence candidates may be considered "gaps." For the typical bacterium that can make all 20 amino acids, there are 1-2 gaps in amino acid biosynthesis pathways. For diverse bacteria and archaea that can utilize a carbon source, there is a complete high-confidence catabolic pathway (including a transporter) just 38% of the time, and there is a complete medium-confidence pathway 63% of the time. Gaps may be due to:
GapMind relies on the predicted proteins in the genome and does not search the six-frame translation. In most cases, you can search the six-frame translation by clicking on links to Curated BLAST for each step definition (in the per-step page).
For more information, see:
If you notice any errors or omissions in the step descriptions, or any questionable results, please let us know
by Morgan Price, Arkin group, Lawrence Berkeley National Laboratory