Qualitative effects of Botrytis cinerea infection on a must protein fractio
n were studied by comparing the electrophoretic patterns of musts obtained
from healthy grapes or from grapes highly infected by B. cinerea. Evidence
was obtained that proteins secreted by B. cinerea can degrade grape protein
s. Most of the proteins present in the healthy must, between 20 and 30 kDa
and a major glycoprotein at 62/64 kDa, disappeared in the infected must. Mo
reover an immunochemical technique, using polyclonal antibodies raised agai
nst B. cinerea-secreted proteins, was developed to specifically detect prot
eins originating from B. cinerea in the infected must. This is of particula
r interest when considering that some of the grape proteins participate in
the foaming properties of Champagne wines.