COMPARATIVE-STUDY ON THE STRUCTURE OF THE LIGHT-CHAINS OF HUMAN-IMMUNOGLOBULINS .2. ASSIGNMENT OF A NEW SUBGROUP

The primary structure of the variable region of the human λtype Bence Jones protein NIG-48 was determined by analysis of the N-terminal sequence of the completely reduced and amino-ethylated protein, as well as of five cyanogen bromide fragments. The variable region of NIG-48 contains 112 amino acid residues.The protein NIG-48, having a unique sequence of the variable region, a low degree of homology (about 50%) with λchains of the five other subgroups and the addition of two residues around 65, may represent a new subgroup, namely VλVL. © 1979, by the Japanese Biochemical Society.