Gas phase characterization of the noncovalent quaternary structure of cholera toxin and the cholera toxin B subunit pentamer

Jonathan P. Williams, Daniel C. Smith, Brian N. Green, Brian D. Marsden, Keith R. Jennings, Lynne M. Roberts, James Scrivens

Research output: Contribution to journalArticleResearchpeer-review

5 Citations (Scopus)

Abstract

Cholera toxin (CTx) is an AB5 cytotonic protein that has medical relevance in cholera and as a novel mucosal adjuvant. Here, we report an analysis of the noncovalent homopentameric complex of CTx B chain (CTx B5) using electrospray ionization triple quadrupole mass spectrometry and tandem mass spectrometry and the analysis of the noncovalent hexameric holotoxin usingelectrospray ionization time-of-flight mass spectrometry over a range of pH values that correlate with those encountered by this toxin after cellular uptake. We show that noncovalent interactions within the toxin assemblies were maintained under both acidic and neutral conditions in the gas phase. However, unlike the related Escherichia coli Shiga-like toxin B5 pentamer (SLTx B), the CTx B5 pentamer was stable at low pH, indicating that additional interactions must be present within the latter. Structural comparison of the CTx B monomer interface reveals an additional a-helix that is absent in the SLTx B monomer. In silico energy calculations support interactions between this helix and the adjacent monomer. These data provide insight into the apparent stabilization of CTx B relative to SLTx B.

Original languageEnglish
Pages (from-to)3246-3254
Number of pages9
JournalBiophysical Journal
Volume90
Issue number9
DOIs
Publication statusPublished - 1 Jan 2006

Fingerprint

Cholera Toxin
Gases
Shiga Toxins
Tandem Mass Spectrometry
Cholera
Computer Simulation
Mass Spectrometry
Escherichia coli
Proteins

Cite this

Williams, Jonathan P. ; Smith, Daniel C. ; Green, Brian N. ; Marsden, Brian D. ; Jennings, Keith R. ; Roberts, Lynne M. ; Scrivens, James . / Gas phase characterization of the noncovalent quaternary structure of cholera toxin and the cholera toxin B subunit pentamer. In: Biophysical Journal. 2006 ; Vol. 90, No. 9. pp. 3246-3254.
@article{a6454511e2c04c998db3b2e616be9382,
title = "Gas phase characterization of the noncovalent quaternary structure of cholera toxin and the cholera toxin B subunit pentamer",
abstract = "Cholera toxin (CTx) is an AB5 cytotonic protein that has medical relevance in cholera and as a novel mucosal adjuvant. Here, we report an analysis of the noncovalent homopentameric complex of CTx B chain (CTx B5) using electrospray ionization triple quadrupole mass spectrometry and tandem mass spectrometry and the analysis of the noncovalent hexameric holotoxin usingelectrospray ionization time-of-flight mass spectrometry over a range of pH values that correlate with those encountered by this toxin after cellular uptake. We show that noncovalent interactions within the toxin assemblies were maintained under both acidic and neutral conditions in the gas phase. However, unlike the related Escherichia coli Shiga-like toxin B5 pentamer (SLTx B), the CTx B5 pentamer was stable at low pH, indicating that additional interactions must be present within the latter. Structural comparison of the CTx B monomer interface reveals an additional a-helix that is absent in the SLTx B monomer. In silico energy calculations support interactions between this helix and the adjacent monomer. These data provide insight into the apparent stabilization of CTx B relative to SLTx B.",
author = "Williams, {Jonathan P.} and Smith, {Daniel C.} and Green, {Brian N.} and Marsden, {Brian D.} and Jennings, {Keith R.} and Roberts, {Lynne M.} and James Scrivens",
year = "2006",
month = "1",
day = "1",
doi = "10.1529/biophysj.105.076455",
language = "English",
volume = "90",
pages = "3246--3254",
journal = "Biophysical Journal",
issn = "0006-3495",
publisher = "Biophysical Society",
number = "9",

}

Gas phase characterization of the noncovalent quaternary structure of cholera toxin and the cholera toxin B subunit pentamer. / Williams, Jonathan P.; Smith, Daniel C.; Green, Brian N.; Marsden, Brian D.; Jennings, Keith R.; Roberts, Lynne M.; Scrivens, James .

In: Biophysical Journal, Vol. 90, No. 9, 01.01.2006, p. 3246-3254.

Research output: Contribution to journalArticleResearchpeer-review

TY - JOUR

T1 - Gas phase characterization of the noncovalent quaternary structure of cholera toxin and the cholera toxin B subunit pentamer

AU - Williams, Jonathan P.

AU - Smith, Daniel C.

AU - Green, Brian N.

AU - Marsden, Brian D.

AU - Jennings, Keith R.

AU - Roberts, Lynne M.

AU - Scrivens, James

PY - 2006/1/1

Y1 - 2006/1/1

N2 - Cholera toxin (CTx) is an AB5 cytotonic protein that has medical relevance in cholera and as a novel mucosal adjuvant. Here, we report an analysis of the noncovalent homopentameric complex of CTx B chain (CTx B5) using electrospray ionization triple quadrupole mass spectrometry and tandem mass spectrometry and the analysis of the noncovalent hexameric holotoxin usingelectrospray ionization time-of-flight mass spectrometry over a range of pH values that correlate with those encountered by this toxin after cellular uptake. We show that noncovalent interactions within the toxin assemblies were maintained under both acidic and neutral conditions in the gas phase. However, unlike the related Escherichia coli Shiga-like toxin B5 pentamer (SLTx B), the CTx B5 pentamer was stable at low pH, indicating that additional interactions must be present within the latter. Structural comparison of the CTx B monomer interface reveals an additional a-helix that is absent in the SLTx B monomer. In silico energy calculations support interactions between this helix and the adjacent monomer. These data provide insight into the apparent stabilization of CTx B relative to SLTx B.

AB - Cholera toxin (CTx) is an AB5 cytotonic protein that has medical relevance in cholera and as a novel mucosal adjuvant. Here, we report an analysis of the noncovalent homopentameric complex of CTx B chain (CTx B5) using electrospray ionization triple quadrupole mass spectrometry and tandem mass spectrometry and the analysis of the noncovalent hexameric holotoxin usingelectrospray ionization time-of-flight mass spectrometry over a range of pH values that correlate with those encountered by this toxin after cellular uptake. We show that noncovalent interactions within the toxin assemblies were maintained under both acidic and neutral conditions in the gas phase. However, unlike the related Escherichia coli Shiga-like toxin B5 pentamer (SLTx B), the CTx B5 pentamer was stable at low pH, indicating that additional interactions must be present within the latter. Structural comparison of the CTx B monomer interface reveals an additional a-helix that is absent in the SLTx B monomer. In silico energy calculations support interactions between this helix and the adjacent monomer. These data provide insight into the apparent stabilization of CTx B relative to SLTx B.

UR - http://www.scopus.com/inward/record.url?scp=33646157075&partnerID=8YFLogxK

U2 - 10.1529/biophysj.105.076455

DO - 10.1529/biophysj.105.076455

M3 - Article

VL - 90

SP - 3246

EP - 3254

JO - Biophysical Journal

JF - Biophysical Journal

SN - 0006-3495

IS - 9

ER -