C-terminal lysine conjugated immunoglobulins

A conjugated immunoglobulin comprising an immunoglobulin and an acyl donor substrate, wherein

• a1) the immunoglobulin comprises one amino acid residue or two amino acid residues after Lysine 447 (K447) on a heavy chain constant region of the immunoglobulin, wherein the amino acid residues are numbered according to the EU numbering system, and wherein, when the immunoglobulin comprises one amino acid residue after K447, the one amino acid residue after the K447 is selected from the group consisting of glycine, alanine, valine, leucine, isoleucine, methionine, phenylalanine, tyrosine, tryptophan, serine, threonine, cysteine, asparagine, glutamine, and histidine;
• and when the immunoglobulin comprises two amino acid residues after K447, the first amino acid residue after the K447 is selected from the group consisting of phenylalanine, leucine, isoleucine, methionine, valine, serine, threonine, alanine, tyrosine, histidine, glutamine, asparagine, lysine, cysteine, tryptophan, arginine, serine, and glycine and the second amino acid residue after the K447 is selected from the group consisting of phenylalanine, leucine, isoleucine, methionine, valine, serine, proline, threonine, alanine, tyrosine, histidine, glutamine, asparagine, aspartic acid, glutamic acid, cysteine, tryptophan and glycine, and
• b1) the acyl donor substrate comprises a glutamine residue and a therapeutic or a diagnostic agent, wherein the K447 of the immunoglobulin is conjugated to the glutamine residue of the acyl donor substrate, wherein the acyl donor substrate is according to one of Formulae (I) or (II):
• (Z)m-Gln-(L)n-(Y) (I)
• (Y)-(L)n-Gln-(Z)m (II)
• wherein
• Z is a carboxylbenzyloxy (CBZ) group or an amino acid residue;
• Gln is a glutamine amino acid residue;
• each L is independently a straight or branched linker from 1 to 20 carbon atoms, wherein one or more of the carbon atoms is optionally and independently replaced with a nitrogen, oxygen or sulfur atom, and wherein each carbon and nitrogen atom is optionally substituted;
• or each L is optionally and independently an amino acid residue;
• m is an integer from 0 to 5;
• n is an integer from 0 to 5;
• and
• Y is a therapeutic or a diagnostic agent;
• or wherein:
• a2) the immunoglobulin comprises at one amino acid residue or two amino acid residues after Lysine 447 (K447) on a heavy chain of the constant region of the immunoglobulin, wherein the amino acid residues are numbered according to the EU numbering system, and wherein, when the immunoglobulin comprises one amino acid residue after K447, the one amino acid residue after the K447 is selected from the group consisting of glycine, alanine, valine, leucine, isoleucine, methionine, phenylalanine, tyrosine, tryptophan, serine, threonine, cysteine, asparagine, glutamine, and histidine;
• and when the immunoglobulin comprises two amino acid residue after K447, the first amino acid residue after the K447 is selected from the group consisting of phenylalanine, leucine, isoleucine, methionine, valine, serine, threonine, alanine, tyrosine, histidine, glutamine, asparagine, lysine, cysteine, tryptophan, arginine, serine, and glycine and the second amino acid residue after the K447 is selected from the group consisting of phenylalanine, leucine, isoleucine, methionine, valine, serine, proline, threonine, alanine, tyrosine, histidine, glutamine, asparagine, aspartic acid, glutamic acid, cysteine, tryptophan and glycine,
• b2) the K447 of the immunoglobulin is conjugated to a glutamine residue on an acyl donor substrate, wherein the acyl donor substrate further comprises a reactive group, wherein the acyl donor substrate is according to one of Formulae (III) or (IV):
• (Z)m-Gln-(L)n-(X) (III)
• (X)-(L)n-Gln-(Z)m (IV)
• wherein
• Z is a carboxylbenzyloxy (CBZ) group or an amino acid residue;
• Gln is a glutamine amino acid residue;
• each L is independently a straight or branched linker from 1 to 20 carbon atoms, wherein one or more of the carbon atoms is optionally and independently replaced with a nitrogen, oxygen or sulfur atom, and wherein each carbon and nitrogen atom is optionally substituted;
• or each L is optionally and independently an amino acid residue;
• m is an integer from 0 to 5;
• n is an integer from 0 to 5;
• and
• X is a reactive group;
• and
• c2) the reactive group is conjugated to a therapeutic agent or a diagnostic agent.