GlmM (PA4749) is the phosphoglucosamine mutase of Pseudomonas aeruginosa, a member of the alpha-D-phosphohexomutase superfamily. It converts glucosamine-6-phosphate to glucosamine-1-phosphate, the second step of the hexosamine branch leading to UDP-N-acetylglucosamine, the common precursor of peptidoglycan and lipopolysaccharide. The P. aeruginosa gene complements an E. coli glmM mutant, restoring peptidoglycan synthesis and growth, and the purified His-tagged enzyme has phosphoglucosamine mutase activity similar to the E. coli enzyme. It also shows phosphomannomutase (about 20 percent) and phosphoglucomutase (about 2 percent) side activities, but it cannot replace the dedicated bifunctional PMM/PGM AlgC in alginate synthesis. Like other phosphohexomutases it is expected to use a phosphoserine catalytic intermediate and Mg2+.
| GO Term | Evidence | Action | Reason |
|---|---|---|---|
| GO:0000287 magnesium ion binding | IEA GO_REF:0000120 | ACCEPT | Summary: UniRule/InterPro mapping; phosphohexomutases use Mg2+ bound at the catalytic phosphoserine site. Reason: Family-wide cofactor (HAMAP GlmM rule); not assayed in this paper but consistent with the superfamily. Supporting Evidence: PMID:10913078 The product of this gene is here identified as the phosphoglucosamine mutase (GlmM) which catalyzes the conversion of glucosamine-6-phosphate to glucosamine-1-phosphate |
| GO:0004614 phosphoglucomutase activity | IDA PMID:10913078 Identification of the Pseudomonas aeruginosa glmM gene, enco... | MARK AS OVER ANNOTATED | Summary: PseudoCAP IDA row: PGM activity is about 2 percent of the GlmM activity of the purified enzyme. Reason: Real but low in vitro side activity of unknown physiological relevance; the dedicated PGM/PMM AlgC exists and GlmM does not substitute for it. Not removed because it was measured on purified enzyme. Not a PAINT seed. Supporting Evidence: PMID:10913078 Beside its phosphoglucosamine mutase activity, the P. aeruginosa enzyme is shown to exhibit phosphomannomutase and phosphoglucomutase activities, which represent about 20 and 2% of its GlmM activity, respectively. PMID:10913078 when plasmid pIT352 was introduced by triparental mating into the algC mutant strain P. aeruginosa 8858, alginate synthesis was not restored |
| GO:0004614 phosphoglucomutase activity | IEA GO_REF:0000117 | MARK AS OVER ANNOTATED | Summary: ARBA prediction of PGM activity. Reason: As for the IDA row: a 2 percent side activity, not the evolved function. Supporting Evidence: PMID:10913078 Beside its phosphoglucosamine mutase activity, the P. aeruginosa enzyme is shown to exhibit phosphomannomutase and phosphoglucomutase activities, which represent about 20 and 2% of its GlmM activity, respectively. |
| GO:0004615 phosphomannomutase activity | IBA GO_REF:0000033 | KEEP AS NON CORE | Summary: IBA from the deep phosphohexomutase node PTN001096974 (136 leaves), seeded by T. kodakarensis PGM/PMM Q68BJ6 and by this gene's PseudoCAP IDA row (self-seed). Reason: GlmM has a genuine, conserved PMM side activity (20 percent, also seen for E. coli GlmM), so the transfer is not false, but PMM is not GlmM's evolved function; AlgC is the P. aeruginosa PMM. The node also contains bona fide PMMs (ManB, RfbK, Pmm) so the node term suits the clade. Supporting Evidence: PMID:10913078 Beside its phosphoglucosamine mutase activity, the P. aeruginosa enzyme is shown to exhibit phosphomannomutase and phosphoglucomutase activities, which represent about 20 and 2% of its GlmM activity, respectively. PMID:10913078 GlmM enzymes from P. aeruginosa and E. coli exhibit additional PMM (relatively high) and PGM (low) activities |
| GO:0004615 phosphomannomutase activity | IDA PMID:10913078 Identification of the Pseudomonas aeruginosa glmM gene, enco... | KEEP AS NON CORE | Summary: PseudoCAP IDA seed of PTN001096974: purified GlmM shows PMM activity at 20 percent of its GlmM activity. Reason: Seed SOUND as a measurement (full text read): the activity was assayed on purified enzyme. It is a secondary activity; GlmM does not restore alginate synthesis in an algC mutant. Supporting Evidence: PMID:10913078 Beside its phosphoglucosamine mutase activity, the P. aeruginosa enzyme is shown to exhibit phosphomannomutase and phosphoglucomutase activities, which represent about 20 and 2% of its GlmM activity, respectively. PMID:10913078 when plasmid pIT352 was introduced by triparental mating into the algC mutant strain P. aeruginosa 8858, alginate synthesis was not restored |
| GO:0004615 phosphomannomutase activity | IEA GO_REF:0000117 | KEEP AS NON CORE | Summary: ARBA prediction of PMM activity. Reason: Consistent with the IDA and IBA rows. Supporting Evidence: PMID:10913078 Beside its phosphoglucosamine mutase activity, the P. aeruginosa enzyme is shown to exhibit phosphomannomutase and phosphoglucomutase activities, which represent about 20 and 2% of its GlmM activity, respectively. |
| GO:0005829 cytosol | IBA GO_REF:0000033 | ACCEPT | Summary: IBA from PTN000501735 seeded by E. coli GlmM. Reason: Soluble cytoplasmic enzyme; overproduced P. aeruginosa GlmM is mostly soluble. Supporting Evidence: PMID:10913078 most of it (about 90%) was recovered in the soluble fraction |
| GO:0005975 carbohydrate metabolic process | IEA GO_REF:0000002 | MODIFY | Summary: InterPro phosphohexomutase mapping to carbohydrate metabolic process. Reason: Correct but general; the specific process is GO:0006048 UDP-N-acetylglucosamine biosynthetic process, accepted here (GO:0006048 is not an is_a descendant of GO:0005975, so MODIFY rather than TOO_GENERAL). Proposed replacements: UDP-N-acetylglucosamine biosynthetic process Supporting Evidence: PMID:10913078 the first step in the biosynthetic pathway leading to the formation of UDP- N -acetylglucosamine |
| GO:0006048 UDP-N-acetylglucosamine biosynthetic process | IBA GO_REF:0000033 | ACCEPT | Summary: IBA from PTN000501735 seeded by E. coli GlmM. Reason: GlcN-6-P to GlcN-1-P is a step of UDP-GlcNAc synthesis; supported by this gene's activity data. Supporting Evidence: PMID:10913078 The product of this gene is here identified as the phosphoglucosamine mutase (GlmM) which catalyzes the conversion of glucosamine-6-phosphate to glucosamine-1-phosphate PMID:10913078 the first step in the biosynthetic pathway leading to the formation of UDP- N -acetylglucosamine |
| GO:0008966 phosphoglucosamine mutase activity | IBA GO_REF:0000033 | ACCEPT | Summary: IBA from PTN000501735 seeded by E. coli GlmM and this gene (self-seed). Reason: Core function; IBD stands on E. coli GlmM. Supporting Evidence: PMID:10913078 The product of this gene is here identified as the phosphoglucosamine mutase (GlmM) which catalyzes the conversion of glucosamine-6-phosphate to glucosamine-1-phosphate |
| GO:0008966 phosphoglucosamine mutase activity | IDA PMID:10913078 Identification of the Pseudomonas aeruginosa glmM gene, enco... | ACCEPT | Summary: PseudoCAP IDA seed of PTN000501735: purified enzyme has phosphoglucosamine mutase activity. Reason: Seed SOUND (full text read). Core molecular function. Supporting Evidence: PMID:10913078 The product of this gene is here identified as the phosphoglucosamine mutase (GlmM) which catalyzes the conversion of glucosamine-6-phosphate to glucosamine-1-phosphate PMID:10913078 shown to restore normal peptidoglycan biosynthesis and cell growth of a glmM Escherichia coli mutant strain |
| GO:0008966 phosphoglucosamine mutase activity | IEA GO_REF:0000120 | ACCEPT | Summary: UniRule/EC/Rhea mapping; agrees with the IDA. Reason: Same claim as the IDA row. Supporting Evidence: PMID:10913078 The product of this gene is here identified as the phosphoglucosamine mutase (GlmM) which catalyzes the conversion of glucosamine-6-phosphate to glucosamine-1-phosphate |
| GO:0009252 peptidoglycan biosynthetic process | IBA GO_REF:0000033 | ACCEPT | Summary: IBA from PTN000501735 seeded by E. coli GlmM and this gene. Reason: GlmM supplies a step of the peptidoglycan precursor pathway; IBD stands on E. coli GlmM. Supporting Evidence: PMID:10913078 shown to restore normal peptidoglycan biosynthesis and cell growth of a glmM Escherichia coli mutant strain |
| GO:0009252 peptidoglycan biosynthetic process | IDA PMID:10913078 Identification of the Pseudomonas aeruginosa glmM gene, enco... | ACCEPT | Summary: PseudoCAP IDA seed of PTN000501735: the gene restores peptidoglycan synthesis in an E. coli glmM mutant (strictly complementation, nearer IGI than IDA). Reason: Seed SOUND (full text read): the enzyme catalyses a step of the precursor pathway, so it takes part in the process. Supporting Evidence: PMID:10913078 shown to restore normal peptidoglycan biosynthesis and cell growth of a glmM Escherichia coli mutant strain |
| GO:0009252 peptidoglycan biosynthetic process | IEA GO_REF:0000117 | ACCEPT | Summary: ARBA prediction; agrees with the IDA. Reason: Same claim as the IDA row. Supporting Evidence: PMID:10913078 shown to restore normal peptidoglycan biosynthesis and cell growth of a glmM Escherichia coli mutant strain |
| GO:0016868 intramolecular phosphotransferase activity | IEA GO_REF:0000002 | TOO GENERAL | Summary: InterPro mapping to intramolecular phosphotransferase activity. Reason: Entailed by GO:0008966 phosphoglucosamine mutase activity, accepted here. |
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Download this section (compressed HTML)Q: Should the PMM IBD at PTN001096974 sit on a lower node that excludes the bacterial GlmM subclade, given that GlmM's PMM is a side activity? Note that UniProt now assigns the other seed, Q68BJ6, to PANTHER PTHR43771 rather than PTHR42946.
Experiment: Measure kcat/Km of purified GlmM for GlcN-6-P, Man-1-P and Glc-1-P to quantify the side activities, and test glmM overexpression in an algC deletion for LPS core synthesis.
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