Complete mRNA sequence of transferrin from Galleria mellonella was obtained, and compared with those of other species. Until now, two types of insect transferrin were reported. Transferrins in cockroach and termite have two iron binding sites while those in most other insect groups, studied for the protein, have only one. It was suggested that the presence of two types of transferrin was related with transferrin evolution, because vertebrate transferrins have two iron binding sites, called N and C terminal lobe. It was shown that G. mellonella transferrin also has only one iron binding site (N terminal lobe), and the deduced amino acid sequence was most similar to those of Manduca sexta and Bombyx mori.

The Gryllus bimaculatus ferritin was purified from the haemolymph by a consecutive four‐step procedures consisting of 50% ammonium sulfate fractionation, anion exchange column chromatography using HiTrapTM Q column (1.6 x 4 cm, Amersham Bioscience), 70°C heat treatment for 10 min, acid treatment of 0.1 M sodium acetate buffer (pH 6.0), and gel filtration column chromatography using G4000SW column (0.75 x 60 cm, Tosoh, Japan) connected on FPLC system. The purified ferritin was found to have two major subunits of 32 and 30 kDa and three minor subunits of 28, 27, and 25 kDa by 2D electrophoresis analysis. Amino acid composition analysis showed that there are high contents of Asp, Glu, Met, Leu, and Lys residues in ferritin while low contents of Cys, Tyr, and Trp residues in the protein. G. bimaculatus haemolymph ferritin could be classified as a methionine‐rich protein.

Two blue-pigment binding proteins, BP1 and BP2, are present in larval and pupal haemolymph of cabbage white butterfly, Pieris rapae, and fluctuate in expression during development. Both BP1 and BP2 are found in pupal haemolymph in varying proportions as well as in adult haemolymph, while only small amounts of BP2 are found in larval haemolymph. BPs are separated by 75% ammonium sulfate, and then purified effectively by ion exchange column chromatography and preparative gel electrophoresis. It was shown that BP1 and BP2 have molecular masses of 20,244 and 19,878 Da, and isoelectric points of 7.0 and 6.8, respectively. Considering their amino acid compositions and N-terminal amino acid sequences, the two proteins are almost identical except the first N-terminal amino acid. The first amino acid of BP1 is asparagine, whereas the initial residue of BP2 is aspartic acid. Anti-BP1 cross-reacts with BP2, indicating that they have immunological homogeneity. Western blotting analyses revealed that only BP1 was present in the larval tissues such as fat body, integument, muscle, and hindgut. However, BP1 was not found in midgut, Malphigian tubules, and silk gland. BP1 was also present in the protein bodies, and both cuticle and hemocoel sides of larval epidermis cells by the transmission electron microscopic observation. The information in this report will facilitate studies on the molecular biology and biological significance of insect BPs.