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Macromolecule Crystallization Screening Results Analysis

Award Information
Agency: Department of Health and Human Services
Branch: National Institutes of Health
Contract: 2R42GM116283-02
Agency Tracking Number: R42GM116283
Amount: $958,278.00
Phase: Phase II
Program: STTR
Solicitation Topic Code: 100
Solicitation Number: PA15-270
Timeline
Solicitation Year: 2015
Award Year: 2016
Award Start Date (Proposal Award Date): 2016-09-16
Award End Date (Contract End Date): 2019-05-31
Small Business Information
601 GENOME WAY
Huntsville, AL 35806-2908
United States
DUNS: 614372535
HUBZone Owned: No
Woman Owned: No
Socially and Economically Disadvantaged: No
Principal Investigator
 MARC PUSEY
 (256) 859-4896
 mlpusey@bellsouth.net
Business Contact
 DIANA TOH
Phone: (256) 426-2777
Email: diana.toh@ixpressgenes.com
Research Institution
 UNIVERSITY OF ALABAMA IN HUNTSVILLE
 
301 SPARKMAN DRIVE, SKH 229
HUNTSVILLE, AL 35899-0001
United States

 Nonprofit college or university
Abstract

Project Summary
Crystallization followed by subsequent structure determination is a major step in understanding the
structure function relationship of macromolecules Understanding macromolecule structure has become a key
part in the development of new pharmaceuticals and is a major area of NIH research Crystallization however
is also the rate limiting step despite technological efforts to automate the set up and crystallization data
acquisition processes
Macromolecule crystallization conditions are arrived at by screening experiments where the target
material is typically subjected to hundreds or even thousands of different chemical cocktails In most cases
screening experiments fail as they do not result in a crystal We propose that screening experiments contain
useful information about the target proteins behavior in response to the tested solution conditions No screen
or group of screens can systematically cover the combinatorial chemical space for protein crystallization and
we hypothesize that in the absence of clear positive hits scored results can be analyzed to determine these
factors The analysis method developed is called the Associated Experimental Design AED approach The
analysis identified the most significant factors and a condition screen based on those factors is prepared for
each protein and set up In the ongoing Phase I effort the AED software is being progressively evolved
adding functions for aiding in prioritizing the screen factors employed for likely success in crystallization The
software is written to not duplicate input conditions for a given protein in the output i e all output conditions
are new combinations of high probability factors as determined from the analysis The software has been
tested with proteins to date Of the proteins that did not give crystals upon initial screening gave
crystals from screens developed on the basis of the AED analysis Of the remaining proteins gave as
many or more crystals in the single AED based screen than were obtained in the x condition screens
One of these proteins was the RrP RrP archaeal exosome catalytic core complex
Based on the Phase I results the AED method shows considerable promise A major advantage of this
approach is that it fits into existing practice making use of existing materials methods and data routinely
generated in crystallization screening The AED software can be used with any imaging system that gives a
scored assessment of the results for each trial including manual scoring by a user with a simple low power
microscope The Phase I results also showed that it can be used with a reduced more granular scoring scale
Success with this approach will increase the number of hits generated and greatly reduce the time and effort
required for macromolecule crystallization The proposed Phase II effort is to build upon the successful
approach developed in Phase I and further develop the analytical methods employed Successful crystallization and X ray data analysis provides important three dimensional information on the
macromolecules structure function relationship important to the design of pharmaceuticals Screening
experiments to identify crystallization conditions typically return non crystalline results This proposal is to
further develop and test software for the analysis of screening data scores to identify likely significant
crystallization factors providing an analytical basis for subsequent experiments and thereby increasing the
chances of success

* Information listed above is at the time of submission. *

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