Galactose mutarotase

Function

Galactose mutarotase (GalM) reversibly converts α-lactose to β-lactose. GalM catalyzes the first step in galactose metabolism^[1].

Structural highlights

From extensive study of mutations in Lactococcus lactis GalM complexes with various sugars it was found that residues H170 and E304 are critical for the active site binding. .

3D structures of galactose mutarotase

Updated on 03-March-2016

1l7j – LlGalM – Lactococcus lactis

1l7k, 1ns0, 1ns2, 1ns8, 1nsu, 1nsx – LlGalM (mutant) + α-D-galactose
1mmu, 1ns4, 1ns7, 1nsr, 1nss, 1nsv – LlGalM (mutant) + β-D-glucose
1nsz – LlGalM (mutant) + α-D-glucose
1mmx – LlGalM (mutant) + α-L-fuccose
1mmy – LlGalM (mutant) + D-quinovose
1mmz – LlGalM (mutant) + β-L-arabinose
1mn0 – LlGalM (mutant) + D-xylose
1nsm – LlGalM (mutant) + α-D-galactose + β-D-galactose
1lur – GalM – Caenorhabditis elegans
1snz – hGalM – human
1so0 - hGalM (mutant) + α-D-galactose
3mwx - GalM – Bacillus subtilis
3nre – GalM – Escherichia coli

References

1. ↑ Thoden JB, Kim J, Raushel FM, Holden HM. The catalytic mechanism of galactose mutarotase. Protein Sci. 2003 May;12(5):1051-9. PMID:12717027