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Can Mass Spectrometry Detect Viral Infectivity? EffJ&fcjJng TechnoJogl&s

Jody A. Shoemaker1 Jody M.Talley2, Dan Dahling1, G. Shay Fout1 • 'Office of Research and Development, National Exposure

Research Laboratory, Microbiology and Chemical Exposure Assessment Research Division, Cincinnati, OH, 2OakRidge Postdoctoral Fellow

Enviromnental Issue

Viral contamination of drinking water is a
problem.

Viruses (e.g., coxsackie) are now listed on the
U. S. EPA 1998 Contaminant Candidate List as
needing additional research on analytical
methods, occurrence, treatment and health
effects.

Coxsackievirus causes diarrhea and fever and
can cause more severe complications such as
diabetes mellitus and myocarditis.

C oxg ackievir us

Components of Coxsackieviruses

•	Ribonucleic acid surrounded by a capsid

•	Capsids contain multiple copies of 4 proteins: VP I ,VP2,
VP3, and VP4

Coxsackieviruses B3, B5, B6 and A20 strains were studied
by Mass Spectrometry

Electron Microscope
picture of Coxsackievirus B3

from http://www.neubert.netl
BUCKmins.html

Mass Spectrometries (MS) Approach

Purified Virus

Capsid Proteins
Released

if*

y*

*

excess MALDI

matrix (acid) added

o o o o
_ SDOton voooo

^-JVJ MALEH O O O O

o

$
%

Laser

o
o

o
o

The combination of the
laser and the matrix
(acid) ionizes the viral
capsid proteins. These
ions are then detected
by MS as mass-to-
charge (m/z) ratios.

Matrix

Mass Separation

% : # -

Simulated Mass Spectrum

The MS produces a
mass fingerprint of the
4 capsid proteins. This
fingerprint is
characteristic of the
coxsackievirus.

VP4









VP3 VP2

1 1

VP1

m/z

Results

Viral Protein 4 (VP4)

~	Observed MW

~	Predicted MW

Coxsackievirus Strain
B3	B5	B6

B3 and B5 implicated No amino
in diseases such as	acid losses

diabetes mellitus

A ^

Amino acid losses

may play a role in
these disease
processes

t

nple

simpu
gastrointestinal
symptoms

Mass Spectrum of Coxsackievirus B5

Myristate is a long fatty
acid chain that is attached to
VP4 in infectious
coxsackieviruses

VP4 + myristate = infectious virus

6900 7400 7900 8400

Impact of Research

Mass spectrometry is an emerging tool in the study of viruses

•	First time a biomarker of infectivity has been tentatively
identified by MS

•	MS can provide information regarding specific proteins contained
within infective/viable microorganisms

This information can be used to develop more rapid, sensitive
methods for microorganisms in drinking water

Partnering to Protect Human Health and the Environment

The study of proteins using mass spectrometry is an emerging technique
that can provide valuable information about the proteins/peptides
present in microbiological organisms.

Matrix assisted laser desorption ionization-
mass spectrometry (MALDI-MS) is used to
create characteristic mass fingerprints of
the viral capsid proteins.

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