Preliminary crystallographic data on the human λIII Bence Jones protein dimer Cle

A complete human λ Bence Jones protein dimer (Cle) has been isolated and crystallized. Protein Cle was characterized immunochemically and chemically as having a variable region amino acid sequence associated with light chains of the λ chain subgroup, λIII, and a constant region sequence characteristic of “non-Mcg” type λ chains. Bence Jones protein Cle contains two covalently bound intact monomers, each having a molecular weight of ~23,000. Crystals of Bence Jones protein Cle, obtained from ammonium sulfate solutions, diffract to 2.6 Å resolution and have the orthorhombic space group P2 12 12 1 with cell dimensions a = 113.0 A ̊ , b = 72.3 A ̊ , and c = 48.9 A ̊ . The asymmetric unit consists of a dimer with a molecular weight of ~ 46,000.