GapMind for Amino acid biosynthesis


L-histidine biosynthesis in Thiomicrospira microaerophila ASL8-2

Best path

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


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

11 steps (11 with candidates)

Or see definitions of steps

Step Description Best candidate 2nd candidate
prs ribose-phosphate diphosphokinase NA59_RS02930
hisG ATP phosphoribosyltransferase NA59_RS02140
hisI phosphoribosyl-ATP pyrophosphatase NA59_RS13125 NA59_RS02135
hisE phosphoribosyl-AMP cyclohydrolase NA59_RS04590 NA59_RS02135
hisA 1-(5-phosphoribosyl)-5-[(5-phosphoribosylamino)methylideneamino]imidazole-4-carboxamide isomerase NA59_RS13115 NA59_RS13120
hisF imidazole glycerol phosphate synthase, cyclase subunit NA59_RS13120 NA59_RS13115
hisH imidazole glycerol phosphate synthase, amidotransferase subunit NA59_RS13110 NA59_RS13120
hisB imidazoleglycerol-phosphate dehydratase NA59_RS13105
hisC histidinol-phosphate aminotransferase NA59_RS00275 NA59_RS02130
hisN histidinol-phosphate phosphatase NA59_RS06220 NA59_RS13105
hisD histidinal/histidinol dehydrogenase NA59_RS02135

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 Apr 09 2024. The underlying query database was built on Apr 09 2024.



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:

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