Active-Site Flexibility and Substrate Specificity in a Bacterial Virulence Factor: Crystallographic Snapshots of an Epoxide Hydrolase

Kelli L. Hvorecny, Christopher D. Bahl, Seiya Kitamura, Kin Sing Stephen Lee, Bruce D. Hammock, Christophe Morisseau, Dean R. Madden

Research output: Contribution to journalArticle

4 Citations (Scopus)

Abstract

Pseudomonas aeruginosa secretes an epoxide hydrolase with catalytic activity that triggers degradation of the cystic fibrosis transmembrane conductance regulator (CFTR) and perturbs other host defense networks. Targets of this CFTR inhibitory factor (Cif) are largely unknown, but include an epoxy-fatty acid. In this class of signaling molecules, chirality can be an important determinant of physiological output and potency. Here we explore the active-site chemistry of this two-step α/β-hydrolase and its implications for an emerging class of virulence enzymes. In combination with hydrolysis data, crystal structures of 15 trapped hydroxyalkyl-enzyme intermediates reveal the stereochemical basis of Cif's substrate specificity, as well as its regioisomeric and enantiomeric preferences. The structures also reveal distinct sets of conformational changes that enable the active site to expand dramatically in two directions, accommodating a surprising array of potential physiological epoxide targets. These new substrates may contribute to Cif's diverse effects in vivo, and thus to the success of P. aeruginosa and other pathogens during infection. Hvorecny et al. crystallized covalent intermediates of the epoxide hydrolase virulence factor Cif. The structures collectively illuminate Cif's stereospecificity and uncover a new set of fatty acid substrates. Cif can thus target key host immune signals, exacerbating the damage caused by opportunistic pathogens such as P. aeruginosa.

Original languageEnglish (US)
JournalStructure
DOIs
StateAccepted/In press - Dec 21 2016

Fingerprint

Epoxide Hydrolases
Virulence Factors
Substrate Specificity
Pseudomonas aeruginosa
Cystic Fibrosis Transmembrane Conductance Regulator
Catalytic Domain
Fatty Acids
Epoxy Compounds
Hydrolases
Enzymes
Virulence
Hydrolysis
Infection

Keywords

  • Enzyme stereospecificity
  • Epoxide hydrolase
  • Epoxy-fatty acids
  • Hydroxyalkyl-enzyme intermediate
  • Pseudomonas aeruginosa
  • Structure-function relationships
  • Virulence factor
  • X-ray crystallography

ASJC Scopus subject areas

  • Structural Biology
  • Molecular Biology

Cite this

Hvorecny, K. L., Bahl, C. D., Kitamura, S., Lee, K. S. S., Hammock, B. D., Morisseau, C., & Madden, D. R. (Accepted/In press). Active-Site Flexibility and Substrate Specificity in a Bacterial Virulence Factor: Crystallographic Snapshots of an Epoxide Hydrolase. Structure. https://doi.org/10.1016/j.str.2017.03.002

Active-Site Flexibility and Substrate Specificity in a Bacterial Virulence Factor : Crystallographic Snapshots of an Epoxide Hydrolase. / Hvorecny, Kelli L.; Bahl, Christopher D.; Kitamura, Seiya; Lee, Kin Sing Stephen; Hammock, Bruce D.; Morisseau, Christophe; Madden, Dean R.

In: Structure, 21.12.2016.

Research output: Contribution to journalArticle

Hvorecny, Kelli L. ; Bahl, Christopher D. ; Kitamura, Seiya ; Lee, Kin Sing Stephen ; Hammock, Bruce D. ; Morisseau, Christophe ; Madden, Dean R. / Active-Site Flexibility and Substrate Specificity in a Bacterial Virulence Factor : Crystallographic Snapshots of an Epoxide Hydrolase. In: Structure. 2016.
@article{831d5048ca484fca88f9fa02eb0590e2,
title = "Active-Site Flexibility and Substrate Specificity in a Bacterial Virulence Factor: Crystallographic Snapshots of an Epoxide Hydrolase",
abstract = "Pseudomonas aeruginosa secretes an epoxide hydrolase with catalytic activity that triggers degradation of the cystic fibrosis transmembrane conductance regulator (CFTR) and perturbs other host defense networks. Targets of this CFTR inhibitory factor (Cif) are largely unknown, but include an epoxy-fatty acid. In this class of signaling molecules, chirality can be an important determinant of physiological output and potency. Here we explore the active-site chemistry of this two-step α/β-hydrolase and its implications for an emerging class of virulence enzymes. In combination with hydrolysis data, crystal structures of 15 trapped hydroxyalkyl-enzyme intermediates reveal the stereochemical basis of Cif's substrate specificity, as well as its regioisomeric and enantiomeric preferences. The structures also reveal distinct sets of conformational changes that enable the active site to expand dramatically in two directions, accommodating a surprising array of potential physiological epoxide targets. These new substrates may contribute to Cif's diverse effects in vivo, and thus to the success of P. aeruginosa and other pathogens during infection. Hvorecny et al. crystallized covalent intermediates of the epoxide hydrolase virulence factor Cif. The structures collectively illuminate Cif's stereospecificity and uncover a new set of fatty acid substrates. Cif can thus target key host immune signals, exacerbating the damage caused by opportunistic pathogens such as P. aeruginosa.",
keywords = "Enzyme stereospecificity, Epoxide hydrolase, Epoxy-fatty acids, Hydroxyalkyl-enzyme intermediate, Pseudomonas aeruginosa, Structure-function relationships, Virulence factor, X-ray crystallography",
author = "Hvorecny, {Kelli L.} and Bahl, {Christopher D.} and Seiya Kitamura and Lee, {Kin Sing Stephen} and Hammock, {Bruce D.} and Christophe Morisseau and Madden, {Dean R.}",
year = "2016",
month = "12",
day = "21",
doi = "10.1016/j.str.2017.03.002",
language = "English (US)",
journal = "Structure with Folding & design",
issn = "0969-2126",
publisher = "Cell Press",

}

TY - JOUR

T1 - Active-Site Flexibility and Substrate Specificity in a Bacterial Virulence Factor

T2 - Crystallographic Snapshots of an Epoxide Hydrolase

AU - Hvorecny, Kelli L.

AU - Bahl, Christopher D.

AU - Kitamura, Seiya

AU - Lee, Kin Sing Stephen

AU - Hammock, Bruce D.

AU - Morisseau, Christophe

AU - Madden, Dean R.

PY - 2016/12/21

Y1 - 2016/12/21

N2 - Pseudomonas aeruginosa secretes an epoxide hydrolase with catalytic activity that triggers degradation of the cystic fibrosis transmembrane conductance regulator (CFTR) and perturbs other host defense networks. Targets of this CFTR inhibitory factor (Cif) are largely unknown, but include an epoxy-fatty acid. In this class of signaling molecules, chirality can be an important determinant of physiological output and potency. Here we explore the active-site chemistry of this two-step α/β-hydrolase and its implications for an emerging class of virulence enzymes. In combination with hydrolysis data, crystal structures of 15 trapped hydroxyalkyl-enzyme intermediates reveal the stereochemical basis of Cif's substrate specificity, as well as its regioisomeric and enantiomeric preferences. The structures also reveal distinct sets of conformational changes that enable the active site to expand dramatically in two directions, accommodating a surprising array of potential physiological epoxide targets. These new substrates may contribute to Cif's diverse effects in vivo, and thus to the success of P. aeruginosa and other pathogens during infection. Hvorecny et al. crystallized covalent intermediates of the epoxide hydrolase virulence factor Cif. The structures collectively illuminate Cif's stereospecificity and uncover a new set of fatty acid substrates. Cif can thus target key host immune signals, exacerbating the damage caused by opportunistic pathogens such as P. aeruginosa.

AB - Pseudomonas aeruginosa secretes an epoxide hydrolase with catalytic activity that triggers degradation of the cystic fibrosis transmembrane conductance regulator (CFTR) and perturbs other host defense networks. Targets of this CFTR inhibitory factor (Cif) are largely unknown, but include an epoxy-fatty acid. In this class of signaling molecules, chirality can be an important determinant of physiological output and potency. Here we explore the active-site chemistry of this two-step α/β-hydrolase and its implications for an emerging class of virulence enzymes. In combination with hydrolysis data, crystal structures of 15 trapped hydroxyalkyl-enzyme intermediates reveal the stereochemical basis of Cif's substrate specificity, as well as its regioisomeric and enantiomeric preferences. The structures also reveal distinct sets of conformational changes that enable the active site to expand dramatically in two directions, accommodating a surprising array of potential physiological epoxide targets. These new substrates may contribute to Cif's diverse effects in vivo, and thus to the success of P. aeruginosa and other pathogens during infection. Hvorecny et al. crystallized covalent intermediates of the epoxide hydrolase virulence factor Cif. The structures collectively illuminate Cif's stereospecificity and uncover a new set of fatty acid substrates. Cif can thus target key host immune signals, exacerbating the damage caused by opportunistic pathogens such as P. aeruginosa.

KW - Enzyme stereospecificity

KW - Epoxide hydrolase

KW - Epoxy-fatty acids

KW - Hydroxyalkyl-enzyme intermediate

KW - Pseudomonas aeruginosa

KW - Structure-function relationships

KW - Virulence factor

KW - X-ray crystallography

UR - http://www.scopus.com/inward/record.url?scp=85017104673&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85017104673&partnerID=8YFLogxK

U2 - 10.1016/j.str.2017.03.002

DO - 10.1016/j.str.2017.03.002

M3 - Article

AN - SCOPUS:85017104673

JO - Structure with Folding & design

JF - Structure with Folding & design

SN - 0969-2126

ER -