For a general linear supergroup G = GL(m|n), we consider a natural isomorphism φ : G → U − × Gev × U + , where Gev is the even subsupergroup of G, and U − , U + are appropriate odd unipotent subsupergroups of G. We compute the action of odd superderivations on the images φ * (x ij ) of the generators of K[G], extending results established in [8] and [7].We describe a specific ordering of the dominant weights X(T ) + of GL(m|n) for which there exists a Donkin-Koppinen filtration of the coordinate algebra K[G]. Let Γ be a finitely generated ideal Γ of X(T ) + and O Γ (K[G]) be the largest Γ-subsupermodule of K[G] having simple composition factors of highest weights λ ∈ Γ. We apply combinatorial techniques, using generalized bideterminants, to determine a basis of G-superbimodules appearing in Donkin-Koppinen filtration of O Γ (K[G]), considered initially in [9].