Inhibition of a bacterial O-GlcNAcase homologue by lactone and lactam derivatives: structural, kinetic and thermodynamic analyses

TY - JOUR

T1 - Inhibition of a bacterial O-GlcNAcase homologue by lactone and lactam derivatives: structural, kinetic and thermodynamic analyses

AU - He, Yuan

AU - Bubb, Abigail K.

AU - Stubbs, Keith A.

AU - Gloster, Tracey M.

AU - Davies, Gideon J.

PY - 2011/3

Y1 - 2011/3

N2 - The dynamic, intracellular, O-GlcNAc modification is of continuing interest and one whose study through targeted "chemical genetics" approaches is set to increase. Of particular importance is the inhibition of the O-GlcNAc hydrolase, O-GlcNAcase (OGA), since this provides a route to elevate cellular O-GlcNAc levels, and subsequent phenotypic evaluation. Such a small molecule approach complements other methods and potentially avoids changes in protein-protein interactions that manifest themselves in molecular biological approaches to O-GlcNAc transferase knockout or over-expression. Here we describe the kinetic, thermodynamic and three-dimensional structural analysis of a bacterial OGA analogue from Bacteroides thetaiotaomicron, BtGH84, in complex with a lactone oxime (LOGNAc) and a lactam form of N-acetylglucosamine and compare their binding signatures with that of the more potent inhibitor O-(2-acetamido-2-deoxy-d-glucopyranosylidene)amino N-phenyl carbamate (PUGNAc). We show that both LOGNAc and the N-acetyl gluconolactam are significantly poorer inhibitors than PUGNAc, which may reflect poorer mimicry of transition state geometry and steric clashes with the enzyme upon binding; drawbacks that the phenyl carbamate adornment of PUGNAc helps mitigate. Implications for the design of future generations of inhibitors are discussed.

AB - The dynamic, intracellular, O-GlcNAc modification is of continuing interest and one whose study through targeted "chemical genetics" approaches is set to increase. Of particular importance is the inhibition of the O-GlcNAc hydrolase, O-GlcNAcase (OGA), since this provides a route to elevate cellular O-GlcNAc levels, and subsequent phenotypic evaluation. Such a small molecule approach complements other methods and potentially avoids changes in protein-protein interactions that manifest themselves in molecular biological approaches to O-GlcNAc transferase knockout or over-expression. Here we describe the kinetic, thermodynamic and three-dimensional structural analysis of a bacterial OGA analogue from Bacteroides thetaiotaomicron, BtGH84, in complex with a lactone oxime (LOGNAc) and a lactam form of N-acetylglucosamine and compare their binding signatures with that of the more potent inhibitor O-(2-acetamido-2-deoxy-d-glucopyranosylidene)amino N-phenyl carbamate (PUGNAc). We show that both LOGNAc and the N-acetyl gluconolactam are significantly poorer inhibitors than PUGNAc, which may reflect poorer mimicry of transition state geometry and steric clashes with the enzyme upon binding; drawbacks that the phenyl carbamate adornment of PUGNAc helps mitigate. Implications for the design of future generations of inhibitors are discussed.

KW - Carbohydrate

KW - Enzyme

KW - X-ray structure

KW - O-GlcNAc

KW - Diabetes

KW - Neurodegeneration

KW - BETA-N-ACETYLGLUCOSAMINIDASE

KW - TRANSITION-STATE MIMICS

KW - INSULIN-RESISTANCE

KW - ALZHEIMERS-DISEASE

KW - SELECTIVE-INHIBITION

KW - 3T3-L1 ADIPOCYTES

KW - D-GLUCOSAMINIDASE

KW - LINKED GLCNAC

KW - MECHANISM

KW - GLYCOSYLATION

UR - http://www.scopus.com/inward/record.url?scp=79954439629&partnerID=8YFLogxK

U2 - 10.1007/s00726-010-0700-6

DO - 10.1007/s00726-010-0700-6

M3 - Article

SN - 0939-4451

VL - 40

SP - 829

EP - 839

JO - AMINO ACIDS

JF - AMINO ACIDS

IS - 3

ER -