KBr 밀도구배 초원심분리와 gel filtration chromatography, preparative electrophoersis을 이용하여 매미나방의 종령 유충 혈림프로부터 biliverdin 결합단백질을 분리, 정제하였다. 정제된 BP는 SDS-PAGE로 소단위 분자량이 약 80kDa, FPLC gel filtration을 사용한 전체분자량은 480 kDa인 것으로 확인되었다. 중성지질로서 triacylglycerol과 diacylglycerol이 BP에 결합되었고, monoacylglycerol은 존재하지 않았다. BP의 아미노산 조성은 glutamic acid 와 aspartic acid가 상대적으로 높은 비율로 존재하였으나 methionine과 tyrosine는 낮은 함량을 보였고 tryptophane은 존재하지 않았다. 또한 BP는 유충시기는 물론 용시기와 성충시기의 혈림프에서도 발견되었다.
Biliverdin-binding protein (BP) was isolated from the last instar larval haemolymph of the gypsy moth, Lymantria dispar and its physicochemical properties were characterized. To purifiy BP from the larva, the haemolymph was subjected to KBr density gradient ultracentrifugation, gel filtration, and preparative electrophoresis. Molecular mass of BP subunits was estimated to be approximately 80 kDa, and native molecular mass found to be 480 kDa by FPLC gel filtration, indicating that BP is a hexamer. BP contains triacylglycerol and diacylglycerol but not monoacylgycerol. Amino acid analysis of BP revealed that this protein is rich in Asp/Asn and Glu/Gln and deficient in Met and Tyr and none of Trp. BP is present in adult haemolymph as well as in larval and pupal haemolymph, but its titre was gradually decreased during postembryonic development.
