Abstract:
Maize lethal necrosis (MLN) is a maize disease caused by the maize chlorotic mottle virus (MCMV), a potyvirus which causes yield losses of
30–100%. The present study aimed to isolate nanobodies against the
MCMV coat protein (CP) for the diagnosis of MLN. MCMV CP
expressed in Escherichia coli was used for llama immunization. VHH (i.e.
variable heavy domain of heavy chain) gene fragments were prepared from
blood drawn from the immunized llama and used to generate a library in
E. coli TG1 cells. MCMV specific nanobodies were selected by three
rounds of phage display and panning against MCMV CP. The selected
nanobodies were finally expressed in E. coli WK6 cells and purified. Eleven
MCMV-specific nanobodies were identified and shown to detect MCMV in
infected maize plants. Thus, our results show that nanobodies isolated
from llama immunized with MCMV CP can distinguish infected and
healthy maize plants, potentially enabling development of affordable
MCMV detection protocols.
