방아깨비(Acrida cinerea)의 혈림프에 존재하는 색소결합단백질인 biliverdin-binding protein들 (BP-1, BP-2)을 확인하였으며, 발생에 따른 변화상, 물리화학적 특성을 조사하였다. Biliverdin-binding protein들의 전기영동 상에서 함량은 BP-2에 비해 BP-1이 높았으며, 모두 발생과정 중 암컷에서는 큰 함량변화가 없었고 수컷에서는 점차감소되었다. ion exchange chromatography, gel filtration 및 electroelution을 통해 정제한 BP들의 전기영동 및 조직화 학적 분석 결과, 이들은 모두 분자량 약 51kDa와 58kDa의 두 subunit로 구성되었으며, BP-1은 약 580kDa, BP-2는 470 kDa의 단백질인 것으로 확인되었다. 두 biliverdin-binding protein (BP-1, BP-2)의 pI값은 모두 약 6.0으로서 구성아미노산의 조성에서 aspartic acid와 proline이 특징적으로 높았으며 다른 곤충류의 색소단백질들과 마찬가지로 aromatic amino acid들(tyrosine, phenylalanine)도 비교적 높게 검출되었다. BP-1은 6$0^{circ}C$, BP-2는 $65^{circ}C$의 온도에 이르기까지 열에 대해 비교적 안정한 단백질인 것으로 확인되었으며, biliverdin의 absorption spectrum상에서 약 375 nm와 650 nm에서 peak가 기록되어 전형적인 biliverdin 결합단백질로서의 특성을 나타내었다.
Biliverdin-binding proteins (BP-1, BP-2) were confirmed, and their physicochemical characteristics were investigated in Acrida cinerea. In the content on electropherogram, BP-1 was higher than BP-2, and their levels were all constant during nymphal and adult development in female, but gradually decreased in male. As the results from electrophoretic and histochemical analysis of purified BPs through electroelution, gel filtration and ion exchange chromatography, they were all confirmed to be protein of M.W. 580 kDa (BP-1) and 470 kDa (BP-2) composed of two common subunits of 51 kDa and 58 kDa. Isoelectric point of the two BPs were about 6.0, respectively. The high contents of proline and aspartic acid were characteristic commonly to these proteins, and also somewhat high aromatic amino acid (tyrosine, phenylalanine) composition was shown similarity to the biliverdin-binding proteins from other insects. These biliverdin-binding proteins were stable to relatively high temperature (BP-1; 6$0^{circ}C$, BP-2; $65^{circ}C$) and all exhibited the peaks at ≒ 375 nm and ≒ 650 nm in the absorption spectra, showing the typical characteristics as biliverdin-binding protein.
