Gelation mechanism of fish proteins.

用圆二色谱、DSC和流变仪研究了α-螺旋在环境中的作用。1)用差示扫描量热法研究了几种鱼类肌球蛋白在不同环境温度下的热稳定性。荧光强度和圆二色谱2)α-螺旋含量急剧下降的温度范围与吸热峰的温度范围非常接近。3)鱼肌球蛋白的结构比兔肌球蛋白的结构更不稳定。4)几种鱼肌球蛋白在30ﾟC或40ﾟC孵育过程中α-螺旋度降低。5)不同物种降低的幅度和方式不同。6)当在30ﾟC或40ﾟC预孵化凝胶强度的下降速率与凝胶强度的上升速率作图时，这两个因素密切相关。从1)-6)，我们认为，鱼肌球蛋白α-螺旋的解离启动了SET。

Participation of the alpha-helix in setting was investigated using circular dichroism, DSC and Rheometer.1)Thermal stability of myosin from several species of fish adapted to different environmental temperatures has been studied by using differential scanning calorimetery, fluorescence intensity and circular dichroism.2)The temperature range of the sharp decrease in the alpha-helical content agreed very closely with that of the endothermic peaks.3)The structure of fish myosin was much more unstable than that of rabbit.4)The alpha-helicity of the actomyosin from several species of fish decrease during incubation at 30ﾟC or at 40ﾟC.5)The extent and pattern of decrease different among species.6)When rate of decrease was plotted vs rate of increase in strength of gel preincubated at 30ﾟC or 40ﾟC, the two factors correlated closely.From 1)-6), we propose that the unfolding of alpha-helix of fish myosin initiated setting.