Streptococcal Protein G Enhances Antibody Binding to Platinum Sensor Surfaces

Michael E. Stephens^1,2, Terri N. Ellis², Jay S. Huebner³, Erica M. Kelly³, Doria F. Bowers^2*

¹Department of Molecular and Cell Biology, University of Connecticut, Storrs, USA.
²Department of Biology, University of North Florida, Jacksonville, USA.
³Department of Physics, University of North Florida, Jacksonville, USA.

DOI: 10.4236/jst.2015.51001                

Abstract

Photo-Electric Microbe Sensor is a patented biotechnology that detects microbes in aqueous solution by measuring the change in photo-voltage in response to UV light stimulation of a platinum (Pt) disk surface on an electrode before and after immunoprecipitation of microbes. This study aimed to increase the sensitivity of microbe detection by pre-adsorbing recombinant Streptococcal Protein G (PG), to the Pt sensor surface. Streptococcal PG binds the Fc region of mammalian IgG molecules and we investigated the association of PG to Pt and the resulting ability to tether antibodies to the Pt-PG surface. An ELISA protocol was optimized to detect the presence of mouse monoclonal antibodies tethered to Pt immunoaffinity disks, and to determine the recommended blocking solution and reagent concentrations. Our results demonstrate that PG binds to bare Pt, increases IgG affinity to the Pt surface following Superblock Buffer application, and together offers design-options for Pt-based sensor technologies.

Keywords

Platinum Sensor Surface, Microbe, Photo-Voltages, Immunoaffinity

Conflicts of Interest

The authors declare no conflicts of interest.

References

[1]	Huebner, J.S., Mejia, E.N. and Bowers, D.F. (2011) Sensing Device and Method for Rapidly Determining Concentrations of Microbial Organisms Using Interfacial Photo-Voltages. The US Patent Office Issued Patent Number 7892495.
[2]	Cosman, N.P. and Roscoe, S.G. (2004) Electrochemical Quartz Crystal Nanobalance (EQCN) Studies of Protein Interfacial Behavior at Pt. Langmuir, 20, 1711-1720. http://dx.doi.org/10.1021/la035154h
[3]	Myhre, E.B. and Kronvall, G. (1977) Heterogeneity of Nonimmune Immunoglobulin Fc Reactivity among Gram-Positive Cocci: Descriptions of Three Major Types of Receptors for Human Immunoglobulin G. Infection and Immunity, 17, 475-482.
[4]	Bjorck, I. and Kronvall, G. (1984) Purification and Some Properties of Streptococcal Protein G, a Novel IgG-Binding Reagent. J. Immunol., 133, 969-974.
[5]	Sauer-Eriksson, A.E., Klewegt, F.J., Uhlen, M. and Jones, T.A. (1995) Crystal Structure of the C2 Fragment of Streptococcal Protein G in Complex with the Fc Domain of Human IgG. Structure, 3, 265-278. http://dx.doi.org/10.1016/S0969-2126(01)00157-5
[6]	Gronenborn, A., Filpula, D., Essig, N., Achari, A., Whitlow, M., Wingfield, P. and Clore, G. (1991) A Novel, Highly Stable Fold of the Immunoglobulin Binding Domain of Streptococcal Protein G. Science, 253, 657-661. http://dx.doi.org/10.1126/science.1871600
[7]	Nordenfelt, P., Waldemarson, S., Linder, A., Morgelin, M., Karlsson, C., Malmstrom, J. and Bjorck, L. (2012) Antibody Orientation at Bacterial Surfaces Is Related to Invasion Infection. Journal of Experimental Medicine, 209, 2367-2381. http://dx.doi.org/10.1084/jem.20120325
[8]	Camarero, J.A. (2007) Recent Developments in the Site-Specific Immobilization of Proteins onto Solid Supports. Biopolymers (Peptide Sci.), 90, 450-458.
[9]	Rusmini, F., Zhong, Z. and Feijen, J. (2007) Protein Immobilization Strategies for Protein Biochips. Biomacromolecules, 8, 1775-1789. http://dx.doi.org/10.1021/bm061197b
[10]	Niu, Y., Matos, A.I., Abrantes, L.M., Viana, A.S. and Jin, G. (2012) Antibody Orientated Immobilization on Gold Using the Reaction between Carbon Disulfide and Amine Groups and Its Application in Immunosensing. Langmuir, 28, 17718-17725. http://dx.doi.org/10.1021/la303032f
[11]	Nuebert, H., Jacoby, E.,Bansai, S., Lies, R., Cowan, D. and Kicman, A. (2002) Enhanced Affinity Capture MALDI- TOF MS: Orientation of an Immunoglobulin G Using Recombinant Protein G. Analytical Chemistry, 74, 3677-3683. http://dx.doi.org/10.1021/ac025558z
[12]	Wanabe, H., Kanazake, K., Nakanishi, T., Shiotsuka, H., Hatakeyama, H., Kaieda, H., Imamura, T., Umetsu, M. and Kumagai, I. (2011) Biomimetic Engineering of Modular Bispecific Antibodies for Biomolecule Immobilization. Langmuir, 16, 9656-9661. http://dx.doi.org/10.1021/la2006259
[13]	Zhang J., Sun, Y., Xu, B., Zhang, H., Gao, Y., Zhang, H. and Song, D. (2013) A Novel Surface Plasmon Resonance Biosensor Based on Grapheme Oxide Decorated with Gold Nanorod-Antibody Conjugates for Determination of Transferrin. Biosensors and Bioelectronics, 45, 230-236. http://dx.doi.org/10.1016/j.bios.2013.02.008
[14]	Hedberg, Y., Wang, X., Hedberg, J., Lundin, M., Blomberg, E. and Wallinder, I.O. (2013) Surface-Protein Interactions on Different Stainless Steel Grades: Effects of Protein Adsorption, Surface Changes and Metal Release. Journal of Materials Science: Materials in Medicine, 24, 1015-1033. http://dx.doi.org/10.1007/s10856-013-4859-8