GlmS/FrlB, SIS domain 2 (IPR035490)

Short name: GlmS/FrlB_SIS

Overlapping homologous superfamilies


Domain relationships


This entry represents the SIS (Sugar ISomerase) domain 2 found in glucosamine 6-phosphate synthase (GlmS) and fructosamine deglycase FrlB.

GlmS contains a N-terminal glutaminase domain and C-terminal isomerase domain (consisting of two SIS domains) [PMID: 9739095] and catalyzes the first step in hexosamine metabolism, converting fructose 6-phosphate into glucosamine 6-phosphate using glutamine as nitrogen source [PMID: 20709015]. The glutaminase domain hydrolyzes glutamine to glutamate and ammonia. Ammonia is transferred through a channel to the isomerase domain for glucosamine 6-phosphate synthesis. In the absence of glutamine, GlmS catalyzes the isomerization of fructose 6-phosphate into glucose 6- phosphate [PMID: 11700065, PMID: 12044898, PMID: 10091662].

FrlB catalyses the conversion of a range of fructosamine 6-phosphates to glucose 6-phosphate and a free amino acid [PMID: 15556630].

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.