GapMind for Amino acid biosynthesis


L-histidine biosynthesis in Azospirillum brasilense Sp245

Best path

prs, hisG, hisI, hisE, hisA, hisF, hisH, hisB, hisC, hisN, hisD?

Also see fitness data for the top candidates


Overview: Histidine biosynthesis in GapMind is based on the MetaCyc pathway (link).

11 steps (10 with candidates)

Or see definitions of steps

Step Description Best candidate 2nd candidate Class of gap
prs ribose-phosphate diphosphokinase AZOBR_RS31185 AZOBR_RS06995  
hisG ATP phosphoribosyltransferase AZOBR_RS19500  
hisI phosphoribosyl-ATP pyrophosphatase AZOBR_RS01690 AZOBR_RS14500  
hisE phosphoribosyl-AMP cyclohydrolase AZOBR_RS08645  
hisA isomerase HisA AZOBR_RS01680 AZOBR_RS01685  
hisF IGP synthase, cyclase subunit AZOBR_RS01685 AZOBR_RS01680  
hisH IGP synthase, amidotransferase subunit AZOBR_RS01670  
hisB IGP dehydratase AZOBR_RS01665  
hisC histidinol-phosphate aminotransferase AZOBR_RS20485 AZOBR_RS08675  
hisN histidinol-phosphate phosphatase AZOBR_RS03845 AZOBR_RS01665  
hisD? histidinol dehydrogenase spurious

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 03 2021. The underlying query database was built on Aug 03 2021.



Related tools

About GapMind

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:

where "other" refers to the best ublast hit to a sequence that is not annotated as performing this step (and is not "ignored").

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 the paper from 2019 on GapMind for amino acid biosynthesis, the paper from 2022 on GapMind for carbon sources, or view the source code, or see changes to Amino acid biosynthesis since the publication.

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