  We compute the one-loop correction to the probe D3-brane action in AdS5 x S5
expanded around the classical Drukker-Fiol solution ending on a circle at the
boundary. It is given essentially by the logarithm of the one-loop partition
function of an Abelian ${\cal N}=4$ vector multiplet in AdS2 x S2 geometry.
This one-loop correction is expected to describe the subleading 1/N term in the
expectation value of circular Wilson loop in the totally symmetric rank k
representation in SU(N) SYM theory at strong coupling. In the limit k << N when
the circular Wilson loop expectation values for the symmetric representation
and for the product of k fundamental representations are expected to match we
find that this one-loop D3-brane correction agrees with the gauge theory result
for the k-fundamental case.
