| Aug.
26, 2005
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Detecting
Anthrax Proteins at Ultralow Concentrations
A
new laboratory
method for quickly detecting active anthrax proteins within
an infected blood sample at extremely low levels has been developed
by researchers at the National Institute of Standards and Technology
(NIST), the U.S. Army Medical Research Institute of Infectious
Diseases and the National Cancer Institute.
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A
computer model shows side and top views of two different
proteins produced by anthrax bacteria. The green molecule
is "protective antigen" (PA), which spontaneously
forms pores that penetrate organic membranes such as cell
walls. The yellow molecule is "lethal factor (LF)."
When a voltage is applied across a membrane studded with
PA pores, both positive and negative ions flow through.
Once LF binds to the pore, however, current only flows
in one direction.
Image
credit: T. Nguyen, National Cancer Institute
Click
on image for a high resolution version.
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Current
detection methods rely on injecting live animals or cell cultures
with samples for analysis and require up to several days before
results are available. Described* in an upcoming issue of the
Journal of Biological Chemistry, the new method produces
unambiguous results in about an hour. The researchers hope the
system will ultimately be useful in developing fast, reliable
ways to diagnose anthrax infections or to quickly screen large
numbers of drugs as possible therapies for blocking the bacteria's
toxic effects.
The method
works by detecting changes in current flow when anthrax proteins
are present in a solution. An anthrax protein ironically called
"protective antigen" spontaneously forms nanometer-scale
pores that penetrate the surface of an organic membrane. When
a voltage is applied across the membrane, positively charged ions flow freely in both directions through the pore.
When additional anthrax proteins called lethal factor (LF) or
edema factor (EF) are present, however, the proteins bind to
the outside of the pore and shut down the flow of ions in one
direction. This change in current flow depends on the concentration
of the proteins in the solution and can detect amounts as low
as 10 picomolar (10 trillionths of a mole per liter).
"We
hope this system will lead to a method for rapidly screening
agents that inhibit the binding of LF or EF to these pores,"
says NIST's lead investigator John Kasianowicz.
Live anthrax antibodies seem to do exactly that. When antibodies
were present in the test solution and then LF was added, the
current flow remained unchanged, indicating that the anthrax
proteins were unable to bind properly. The long-term goal would
be to find drugs with few side effects that also interfere with
this binding process.
* K.M.
Halverson, R.G. Panchal, T. Nguyen, R. Gussio, S.F. Little,
M. Misakian, S. Bavari and J.J. Kasianowicz, "Anthrax Biosensor:
Protective Antigen Ion Channel Asymmetric Blockade," Journal
of Biological Chemistry, slated for a November issue, posted
online Aug. 8, 2005.
Improving
Security of Handheld IT Devices
Handheld
devices such as personal digital assistants are becoming
indispensable tools for today’s highly mobile workforce.
Small and relatively inexpensive, these devices can be used
for many functions, including sending and receiving e-mail,
storing documents, delivering presentations and remotely
accessing data.
While
their small size can be an advantage, it also can be a disadvantage
since handheld devices can be easier to misplace or to steal
than a desktop or notebook computer. If they do fall into
the wrong hands, gaining access to the information they
store can be relatively easy. The National Institute of
Standards and Technology (NIST) has recently issued two
reports aimed at making it harder for unauthorized users
to access information from these devices.
Proximity
Beacons and Mobile Device Authentication (NISTIR 7200)
describes how two different kinds of location-based authentication
mechanisms that use signals from wireless beacons can be
used to authenticate handheld device users. If the user
is in an unauthorized location or a location outside a defined
boundary, access will be denied or an additional authentication
mechanism must be satisfied before gaining access.
While
many organizations use smart cards for security, they require
a card reader that can be nearly as large as the handheld
device. Smart Cards and Mobile Device Authentication
(NISTIR 7206) describes two types of smart cards that use
standard interfaces supported by handheld devices, avoiding
the use of more cumbersome, standard-size smart card readers.
Both
reports describe these innovative authentication mechanisms
and provide details on their design and implementation.
The reports are available at http://csrc.nist.gov/publications/nistir/index.html.
Media
Contact:
Jan
Kosko, janice.kosko@nist.gov,
(301) 975-2767
NIST
Develops 'Toolbox' for Manufacturing Systems
Ask
any handyman what’s the most important thing he needs
to get the job done and he’ll probably say his toolbox.
Thanks to the National Institute of Standards and Technology
(NIST), there’s now a toolbox to help those involved in
the development, validation and implementation of international
standards for manufacturing systems. This toolbox is a Web site
that contains links to databases, software packages, test suites
and other information technology support products and tools
that have been developed in recent years by NIST’s Manufacturing
Systems Integration Division.
For example,
one of the tools in the testing and evaluation support section
contains a “naming assister” that provides guidance
with consistent naming conventions for elements and types based
on ISO 11179 (the international metadata standard). A tool in
the semantic technology support section lets users try their
hand at a “20 Questions” exercise to capture exactly
how their own applications represent processes and activities
in terms of the Process Specification Language. (PSL is a neutral
language that helps manufacturers exchange process information
among different applications in their company.) The third part
of the toolbox—application support—features Expect,
NIST’s software used to glue together different computer
applications and automate the result. Finally, the standards
development section supplies tools for dealing with various
aspects of the STandard for Exchange of Product model data (STEP,
formally known as ISO 10303), which provides a neutral format
that enables the exchange of data between proprietary systems.
To access
the NIST MSID Products and Tools Web site, go to http://www.mel.nist.gov/msid/msidprod.htm.
Consortium
Seeks Comment on Gene Expression Roadmap
The
External RNA Controls Consortium (ERCC) has issued for comment
a draft plan for the selection and qualification of candidate
RNA sequences, to be used as controls for assessing the
performance of gene expression experiments. The ERCC is
an ad hoc group of about 50 companies, universities and
federal laboratories joined to develop materials and tools
that will be used to establish the performance of DNA microarrays
and other quantitative experiments that measure gene expression.
The National Institute of Standards and Technology (NIST)
is a founding member and host of the consortium.
Gene
expression—how and under what conditions specific
genes produce which proteins, and why—is one of the
most important frontiers in bioscience today, promising
a better understanding of fundamental life processes and
the discovery of important biomarkers for early disease
diagnosis. The field was advanced enormously by the development
of powerful technologies such as quantitative, real-time
reverse transcriptase polymerase chain reaction (QRT-PCR)
and the DNA microarray. Both techniques for analyzing gene
expression, however, are complex, involve multiple steps,
various detection technologies and many potential sources
of error. At present, it is difficult to establish the quality
of any particular experiment.
The
ERCC proposes to develop consistent, well-characterized
RNA samples that can be added into gene expression assays
as a check on the performance of the measurement system.
These proposed “external RNA controls”—approximately
100 are envisioned—would be chosen to deliver comparable
results across the range of available microarray and QRT-PCR
systems.
Because
selecting a set of RNA controls that perform consistently
is essential to the success of the project, the ERCC is
planning extensive experimental qualification of the set.
They are publishing for public comment a draft specification
of its proposed methods for testing and selecting the final
set of external RNA controls. The document, “Proposed
Methods for Testing and Selecting the ERCC External RNA
Controls,” is available on-line at www.cstl.nist.gov/biotech/Cell&TissueMeasurements/GeneExpression/ERCC.htm.
Comments can be forwarded via e-mail to ercc@NIST.gov.
The
ERCC will hold a workshop on Oct. 4-5, 2005, at the Lister
Hill Center Auditorium at the National Institutes of Health
in Bethesda, Md., to discuss the draft protocol and review
comments. For further information send e-mail to ercc@nist.gov.
Media
Contact:
Michael
Baum, michael.baum@nist.gov,
(301) 975-2763
IT
Program Hopes to Foster Better Security Checklists
Widespread
electronic attacks on computer systems have become
commonplace with threats ranging from remotely launched
attacks on network services to malicious code spread
through e-mails. To make matters worse, vulnerabilities
in IT products such as operating systems are discovered
almost daily. But, securing today’s complex
systems and products can be very complicated, arduous
and time-consuming for even the most experienced
system administrator.
While
the solutions to IT security are complex, one basic,
yet effective tool is the security configuration
checklist, sometimes called a lockdown or hardening
guide. Basically, a checklist is a series of instructions
for configuring an information technology (IT) product
to a baseline or benchmark level of security.
The
National Institute of Standards and Technology (NIST),
with sponsorship from the Department of Homeland
Security (DHS), has developed a program to facilitate
the development and sharing of security configuration
checklists. The program helps developers make checklists
that conform to common operational environments;
provides guidelines for making better documented
and more usable checklists; provides a managed process
for reviewing, updating and maintaining checklists;
and includes an easy-to-use repository of checklists.
A
new NIST report, Security Configuration Checklists
Program for IT Products—Guidance for Checklists
Users and Developers (NIST Special Publication
800-70) gives an overview of the NIST Checklist
Program, explains how to retrieve checklists from
NIST's repository and provides general information
about threats and baseline technical security policies
for associated operational environments. It also
describes the policies, procedures and general requirements
for checklist developers to participate in the program.
The report and other information is available at
http://checklists.nist.gov.
Media
Contact:
Jan
Kosko, janice.kosko@nist.gov,
(301) 975-2767
Quick
Links
Evaluation
Gauges Results from Machine Translation
The
National Institute of Stanards and Technology has
posted at www.nist.gov/speech/tests/mt
the results of the NIST 2005 Machine Translation
Evaluation (MT-05), part of an ongoing series assessing
the effectiveness of the technologies underlying computerized
text language translation systems. NIST conducts these
evaluations in order to support machine translation
(MT) research and help advance the state of the art
in MT technology. MT-05 consisted of two tasks where
each task required performing translation of text
from a given source language into the target language.
The source languages were Arabic and Chinese, and
the target language was English. Research algorithms
and translation system output—not the systems
themselves—were studied in MT-05. These tests
should not be considered a product-testing exercise.
Therefore,
MT-05 results are not to be construed or represented
as endorsements of any participant's system or commercial
product, or taken as official findings on the part
of NIST or the U.S. government.
Conference
to Highlight New Biometric Technologies
The
Biometrics Consortium Conference 2005 will address
the latest trends in research, development, testing
and application of biometric technologies, especially
in the area of homeland security. Slated for Sept.
19-21, 2005, in Arlington, Va., the conference is
sponsored by the National Institute of Standards and
Technology (NIST), along with seven other federal,
state and non-profit agencies. Topics covered will
include advances in biometric technologies such as
fingerprinting, iris scans, facial and multimodal
biometrics; methods for measuring biometric effectiveness;
biometric standards and adoption; countermeasures
and spoofing; and societal and political implications.
Government programs, large scale implementations,
security of biometrics, and biometrics and physical
access control will be addressed.
More
than 100 speakers will represent the biometrics industry,
universities and federal agencies such as NIST, the
National Security Agency and the Department of Homeland
Security. More than 70 organizations also will provide
exhibits and information on biometric technology.
For more information and to register online, go to
http://www.nist.gov/bc2005.
Reporters
who plan to cover the conference should send an e-mail
to Jan Kosko (kosko@nist.gov)
by close of business Wednesday, Sept. 14, and must
show credentials (a news media badge with a photo
or a photo ID with a business card) to gain admission
to the conference.
Industrial
Physics Forum: Innovation Infrastructure
Industry
executives, research managers, academics and science
policy decision makers are invited to attend The Industrial
Physics Forum on Nov. 6-8, 2005, at the National Institute
of Standards and Technology (NIST) campus in Gaithersburg,
Md. The forum is sponsored annually by the American
Institute of Physics to keep participants current
on the themes and issues affecting the physics community.
This year's theme is Advancing Infrastructure for
Innovation. The first day of the forum will focus
on the latest research at NIST in areas such as public
safety and security, nanotechnology, and biosystems
and health, and will include laboratory tours. The
second day will focus on policy issues and current
trends affecting the physics industry, as well as
a "Frontiers in Physics" session exploring
hot topics such as quantum information and evolution.
For further information and to register, see http://www.aip.org/ca/2005/05mtg.html.
Practice
Guide Describes Engineering Standards
The National Institute of Standards and Technology
(NIST), in cooperation with the ASM International
Surface Engineering Committee, has issued a guide
to published standards for the measurement and characterization
of inorganic material surfaces. NIST Recommended
Practice Guide: Surface Engineering Measurement Standards
for Inorganic Materials (NIST Special Publication
960-9) directs the user to appropriate standards based
on material type, property of interest, and measurement
or characterization method. Each summary includes
a general description of the standard, the intended
application, specimen requirements, type of data produced
and the limits of the method. NIST SP 960-9 may be
downloaded in Adobe Acrobat format at www.msel.nist.gov/practiceguides/SP960_9.pdf (.pdf;
download Acrobat Reader).
A free print copy may be obtained by contacting Joyce
Harris, (301) 975-6045, joyce.harris@nist.gov.
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