AVS 57th International Symposium & Exhibition
    Marine Biofouling Topical Conference Monday Sessions
       Session MB+BI+AS-MoA

Paper MB+BI+AS-MoA10
Solid State Circular Dichroism of Insoluble Bioadhesive Films: Determining Protein Secondary Structure by Concentration Independent Analysis

Monday, October 18, 2010, 5:00 pm, Room Navajo

Session: Preventing & Characterizing Marine Biofouling
Presenter: D.E. Barlow, U.S. Naval Research Laboratory
Authors: D.E. Barlow, U.S. Naval Research Laboratory
J.L. Kulp, U.S. Naval Research Laboratory
K.J. Wahl, U.S. Naval Research Laboratory
Correspondent: Click to Email

Far-UV circular dichroism (CD) is a valuable method for estimating protein structure components. Analysis of protein CD spectra typically requires deconvolution to resolve overlapping bands and standard methods require that the concentration and pathlength of the sample are accurately known. While this is usually not an issue for the solution state, it is sometimes desirable or a necessity to analyze samples as solid films, complicating deconvolution. Barnacle cement is one example of a proteinaceous bioadhesive that is insoluble by standard biochemical methods and of inconsistent thickness in the native state. To analyze such samples by CD, we have applied g-factor analysis,1 where the CD spectra are normalized by absorption spectra. This has been demonstrated as a valid, concentration independent deconvolution method, but so far has not been widely used. We will present protein secondary structure estimation results of barnacle cement films as determined by g-factor analysis and show how these results compare with those obtained by infrared spectroscopy. Potential issues and further applicability of solid state CD for bioadhesion studies will be discussed.

1 McPhie, P. Anal. Biochem. 2001, 293, 109.