Selection and expression of recombinant single domain antibodies (VHHs) against a low molecular weight hapten

AGRO 52

Shokouh Makvandi-Nejad, smakvand@uoguelph.ca1, C. Roger MacKenzie, Roger.MacKenzie@nrc-cnrc.gc.ca2, and J. Christopher Hall, jchall@uoguelph.ca1. (1) Department of Environmental Biology, University of Guelph, Guelph, ON N1G 2W1, Canada, (2) Institute for Biological Sciences, National Research Council of Canada, Ottawa, ON K1A 0R6, Canada
Few recombinant single domain antibodies VHH against low molecular weight haptens have been developed. Therefore, a VHH phage displayed library was constructed by isolating the VHH-coding genes from the lymphocytes collected from a Llama glama immunized with the strobilurin fungicide, azoxystrobin (403 MW), conjugated to bovine serum albumin (BSA). Six rounds of panning were performed against azoxystrobin conjugated to rabbit serum albumin (RSA) to enrich clones containing VHH specific to the hapten. After screening 95 clones, five VHH antibodies with different amino acid sequences were identified, expressed in soluble format in Escherichia coli HB2151, and purified using nickel-immobilized metal affinity chromatography. Competition enzyme-linked immunosorbent assay (ELISA), using free azoxystrobin, azoxystrobin-RSA and RSA, showed all five VHHs were azoxystrobin binders. The IC50 of these VHHs were ca. 10 µM.
 

New Developments and Issues in Agrochemical Sciences
8:00 AM-11:00 AM, Monday, August 20, 2007 BCEC -- Exhibit Hall - B2, Poster

Division of Agrochemicals

The 234th ACS National Meeting, Boston, MA, August 19-23, 2007