Recognition tags for TGase-mediated conjugation

1. An antibody lacking an Fc domain selected from the group consisting of a scFv, an affibody, a V H domain, a V L domain, a V-NAR domain and a V H H domain, comprising a TGase recognition tag comprising a functionalized acceptor glutamine residue (Q) of Formula IV, below,

(Q)-NH—(C) n —X-L-(V—(Y-(M) z ) q ) r   Formula IV

where:

Q is glutamine residue present in the TGase recognition tag;

(C) n is a substituted or unsubstituted alkyl or heteroalkyl chain, optionally wherein any carbon of the chain is substituted with an alkoxy, hydroxyl, alkylcarbonyloxy, alkyl-S—, thiol, alkyl-C(O)S—, amine, alkylamine, amide, or alkylamide;

n is an integer selected from among the range of 2 to 20;

X is NH, O, S, absent, or a bond;

L is independently absent, a bond or a continuation of a bond, or a carbon comprising framework of 5 to 200 atoms substituted at one or more atoms, optionally, wherein the carbon comprising framework comprises a linear framework of 5 to 30 carbon atoms optionally substituted at one or more atoms, optionally wherein the carbon comprising framework is a linear hydrocarbon, a symmetrically or asymmetrically branched hydrocarbon, monosaccharide, disaccharide, linear or branched oligosaccharide (asymmetrically branched or symmetrically branched), other natural linear or branched oligomers (asymmetrically branched or symmetrically branched), or a dimer, trimer, or higher oligomer (linear, asymmetrically branched or symmetrically branched) resulting from any chain-growth or step-growth polymerization process;

r is an integer selected from among 1, 2, 3 or 4;

q is an integer selected from among 1, 2, 3 or 4;

z is an integer selected from among 1, 2, 3 or 4; and

V is independently absent, a non-cleavable moiety or a conditionally-cleavable moiety;

Y is independently absent, a bond or a continuation of a bond, or a spacer system which is comprised of 1 or more spacers;

M is ((RR′)-L′-(V′—(Y′—(Z) z ′) q ′) r ′),

wherein Z is a moiety-of-interest, optionally a moiety that improves the pharmacokinetic properties, or a therapeutic moiety or a diagnostic moiety,

wherein each of L′, V′, Y′, z′, q′, and r′ are as defined as L, V, Y, z, q and r, and

wherein RR′ is an addition product between a reactive moiety R and a complementary reactive moiety R′, wherein R and R′ are moieties capable of undergoing a Huisgen 1,3-cycloaddition reaction, wherein one of the R and R′ is an azide and the other is a strained cycloalkyene.

2. The antibody of claim 1 , wherein Z is an organic compound, having a molecular weight of at least 300 g/mol, 400 g/mol, 500 g/mol, 600 g/mol, 700 g/mol, 800 g/mol, 900 g/mol, 1,000 g/mol or 2,000 g/mol.

3. The antibody of claim 1 , wherein Z is a cytotoxic agent.

4. The antibody of claim 1 , wherein the TGase recognition tag comprises an amino acid sequence of SEQ ID NO: 1 or a variant thereof comprising 1, 2, 3, 4, 5 or 6 amino acid modifications.

5. The antibody of claim 1 , wherein the antibody is selected from an scFv, an affibody, a V H domain, a V L domain, a V-NAR domain and a V H H domain, fused at its N- or C-terminus to a TGase recognition tag comprising an amino acid sequence of SEQ ID NO: 1 or a variant thereof comprising 1, 2, 3, 4, 5 or 6 amino acid modifications.

6. A kit comprising a library of at least 100 antibodies of claim 4 .

7. The kit of claim 6 , wherein the library is produced from a phage display library.

8. The antibody of claim 1 , wherein Z is chemical compound displaying hydrophobic properties.