Investigating Molecular Recognition and Biological Function at Interfaces Using Antimicrobial Peptides.
EMSL Project ID
10595a
Abstract
This research proposal features fundamental principles underlying biological function and mechanisms of action of peptides active at interfaces. The strategy for this project, which we initiated last summer, has been to use complementary solid-state Nuclear Magnetic Resonance (ssNMR) techniques on site-specific isotopically labeled peptides. A number of circular dichroism (CD) and solution NMR experiments have also been planned to help guide the ssNMR work. Syntheses, purification, and identification of the key peptides as well as their preparation for NMR experiments can and have been performed at Pacific Lutheran University (PLU, Tacoma, WA, http://www.plu.edu/). In order to permit progress towards the ssNMR-related goals of this proposal, we are applying for blocks of time on the EMSL 500 WB Varian Unity+ and 600 NB Varian Unity NMR spectrometers. Note that our work, which started in the summer of 2003 with the use of Magic Angle Spinning techniques (REDOR< see below) to obtain distance restraints, is now ready to phase in a complementary technique based on the use of oriented samples to get orientational restraints. It is therefore an exciting time for this project. I would also like to mention that our results collected at the EMSL were featured in a talk, which I was invited to give at an American Chemical Society Symposium on solid-state NMR (Great Lakes Regional Meeting, Peoria, October 2004). So, if the core of our proposal has retained many of its original features, we have clearly made significant progress in achieving our initial goals and the future work proposed here is promising.As part of our plans, the mechanisms of action of piscidins, antimicrobial peptides from mast cells of fish, have been studied through the investigation of structure/dynamics/function relationships. These topics are addressed by a combination of robust ssNMR techniques, which I extensively used in my graduate and post-doctoral research. More precisely, we have performed REDOR distance measurements (13C to 15N) on labeled peptides interacting with hydrated lipid bilayers. Our very next step is to pursue REDOR measurements while varying sample conditions (pH, hydration, freeze-thaw cycles). In addition, two flat coil probes needed to obtain orientational constraints from oriented samples have been purchased through funds recently received from the Research Corporation. Such probes are not available at the EMSL at this point in time and we are very enthusiastic at the idea of testing them at the EMSL during our next scheduled period, which is at the end of March 2005. For the scheduling period of April-October 2005, we anticipate that we will be ready to investigate oriented peptide-lipid samples.
Understanding molecular recognition at interfaces as proposed here can provide some important knowledge needed to fight many diseases and design new drugs, including broad-spectrum ones. Beyond this scientific motivation, a paramount goal of this project is also to provide an environment in which undergraduate students can integrate learning and advanced research. Also, I am applying as the "primary author" but I would like two to three PLU students to be considered access too.
Access to the state of the art facility at EMSL would be pivotal to achieving my pursuits, both from research and educational standpoints. Thank you for your consideration.
Project Details
Project type
Capability Research
Start Date
2005-07-13
End Date
2005-09-30
Status
Closed
Released Data Link
Team
Principal Investigator
Team Members