Detection and Localization of Terrestrial and Extraterrestrial Biomarkers
Using Immunological Techniques Combined with Chemical Force Microscopy

Lead Investigator: Recep Avci, Montana State University
Co-Lead Investigators: Mary Schweitzer, Andrew Steele and Seth Pincus, Montana State University

A chemical force microscope (CFM) acting like nano-velcro allows the detection and localization of individual antibody-antigen (Ab-Ag) interactions with nanometer resolution, hence allowing the combination of bio- and nano-technologies. Our program will develop this technique with an emphasis on detecting traces of extinct or extant life within terrestrial and extraterrestrial materials. The work will be conducted in close collaboration with NASA's Mars Immunoassay Life Detection Instrument (MILDI) project team headed by Dr. David McKay of the Johnson Space Center in Houston. The research has the following objectives: (1) to develop the technique of chemical force microscopy utilizing antibodies in a well-defined experimental system by mapping the antigenic surfaces of a highly characterized biological system, (2) to develop or purchase commercially available antibodies to biomolecules including proteins, DNA, individual amino acids, porphyrins, heme, and to use these antibodies in CFM, (3) to cross-check these results with more accepted techniques such as immunohistochemical staining, immunoblotting and ELISA, (4) to assay a suite of samples which includes bacterial fossils from the Enspel and Messel formations, and meteorites that are known to be contaminated by terrestrial organisms such as ALH84001, Nakhla, Allende and Murchison, and (5) to apply the technique to advanced sample curation issues by assaying lunar materials, and to MILDI for verification during its development. In situ immunohistochemical localization of antibody binding on rock and fossilized bacteria will be done on ultrathin sections of parent rock as well as on fresh fracture faces. For each extraterrestrial sample to be studied, a portion is to be retained for immunohistochemical verification studies. The ability of CFM to identify biological interactions with nanometer resolution offers great potential for the detection of terrestrial and extraterrestrial life, terrestrial contamination, prebiotic chemicals and organic pollutants. Once verified this technique could be further developed as a flight instrument for Ab-Ag studies on robotic or manned missions.

A correlation between the site of antibody binding and the morphological features of an organism or a cell would have important implications in practice. Some biotechnology companies who utilize antibody technologies for studying pathogenic microbes have expressed a great interest in the outcome of the proposed research. Major part of the Ab-Ag preparations will be carried out in the Microbiology Department at MSU though some will be subcontracted to other institutions or will be purchased commercially, and the chemical force microscopy experiments will be carried out in the Image and Chemical Analysis Laboratory at MSU.

Mail:	Recep Avci	E-mail:	avci@physics.montana.edu
	Department of Physics	Phone:	(406) 994-6164
	Montana State University	FAX:	(406) 994-6165
	Bozeman, MT 59717-3840	Website:	Image and Chemical Analysis Laboratory

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