9dqf

From Proteopedia

Crystal structure of bifunctional GlmU from Staphylococcus aureus NCTC 8325 complexed with acetyl CoA and citrate

Structural highlights

9dqf is a 1 chain structure with sequence from Staphylococcus aureus subsp. aureus NCTC 8325. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Method:	X-ray diffraction, Resolution 1.9Å
Ligands:	,
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

GLMU_STAA8 Catalyzes the last two sequential reactions in the de novo biosynthetic pathway for UDP-N-acetylglucosamine (UDP-GlcNAc). The C-terminal domain catalyzes the transfer of acetyl group from acetyl coenzyme A to glucosamine-1-phosphate (GlcN-1-P) to produce N-acetylglucosamine-1-phosphate (GlcNAc-1-P), which is converted into UDP-GlcNAc by the transfer of uridine 5-monophosphate (from uridine 5-triphosphate), a reaction catalyzed by the N-terminal domain.

Publication Abstract from PubMed

The bifunctional enzyme N-acetylglucosamine 1-phosphate uridyltransferase (GlmU) is a promising antibiotic drug target, as it facilitates the biosynthesis of uridine 5'-diphospho-N-acetylglucosamine, an essential precursor of cell wall constituents. We identified that Staphylococcus aureus GlmU (SaGlmU), which was previously targeted for inhibitor development, possesses a dual-cysteine variation (C379/C404) within the acetyltransferase active site. Enzyme assays performed under reducing and non-reducing conditions revealed that the acetyltransferase activity of SaGlmU is redox-sensitive, displaying ~15-fold lower turnover and ~3-fold higher K(M) value for the acetyl CoA substrate under non-reducing conditions. This sensitivity was absent in a C379A SaGlmU mutant. Analysis of SaGlmU by mass spectrometry, x-ray crystallography, and in silico modeling support that C379 and C404 act as a reversible, redox-sensitive switch by forming a disulfide under non-reducing conditions that impedes acetyl CoA recognition and turnover. Therefore, we recommend that future in vitro screening and characterization of SaGlmU inhibitors consider both reducing and non-reducing conditions.

Functional and structural characterization of Staphylococcus aureus N-acetylglucosamine 1-phosphate uridyltransferase (GlmU) reveals a redox-sensitive acetyltransferase activity.,Pederick JL, Kumar A, Pukala TL, Bruning JB Protein Sci. 2025 Apr;34(4):e70111. doi: 10.1002/pro.70111. PMID:40143772^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

References

↑ Pederick JL, Kumar A, Pukala TL, Bruning JB. Functional and structural characterization of Staphylococcus aureus N-acetylglucosamine 1-phosphate uridyltransferase (GlmU) reveals a redox-sensitive acetyltransferase activity. Protein Sci. 2025 Apr;34(4):e70111. PMID:40143772 doi:10.1002/pro.70111