Pseudomonas syringae로부터 빙핵활성을 갖는 단백질을 분리 정제하였다. 빙핵활성단백질은 균주로부터 분리한 세포외막에 비변성 계면활성제로 추출하고, Sephacryl S-400 크로마토그래피와 전기영동 용출법으로 정제하였다. 빙핵활성단백질은 분자량이 전기영동상에서 150,000 dalton 이었다. 빙핵활성의 측정은 모세관측정법을 사용하였고 정제된 단백질은 $-8^{circ}C$에서 빙핵활성을 나타냈다.
The protein responsible for ice-nucleation activity by Pseudomonas syringae AL (KCTC 1832) has been purified. The protein was purified from the outer membrane fraction of the cell by methods including extraction with non-denaturing detergents octyl-${eta}$-D-thioglucopyranoside, gel filtration chromatography on Sephacryl S-400 and gel electroelution. The molecular weight of the ice-nucleating protein is estimated to be about 150,000 dalton by SDS-PAGE. Ice-nucleation activity was measured by the micro-pipette method. Ice-nucleation activity of the purified protein was about $-8{sim}-9^{circ}C$, whereas the freezing point of supercooled water is $-17^{circ}C$.
