摘要
引起水由液态变为固态的物质称为冰核或成核剂 ,冰核是多种多样的 ,可为无机物、有机物等非生物 ,也可是生物 ,目前已发现 4属 2 3种或变种的细菌、4属 11种或变种的真菌和一种病毒具成冰活性。细菌冰核是一类蛋白质 ,称冰蛋白 ,由细菌冰核基因编码 ,已有 11种冰核细菌的冰核基因被克隆并在大肠杆菌中得到表达 ,冰核基因编码的冰蛋白成冰活性比较弱 ,冰蛋白通过脂、碳水化合物等共价修饰装配成成冰活性较强的冰核。真菌冰核也可能是蛋白质 ,其与细菌冰核在特性上有许多差异。影响细菌冰核成冰活性的因素较多 ,主要有菌液浓度、培养基的组成、培养温度和 p H值等。生物冰核是引起和加重植物霜害和冻害的重要因子 ,并与弱寄生真菌引起的植物病害有重要的联系 ,通过防除冰核生物减少霜害和冻害的发生、控制病害的发展 ,在某些方面已得到显著效果。生物冰核是一类重要的资源 ,已成功地应用于人工降雪、制冷和高敏检测 。
It have been proved that 4 genera 23 species or varieties bacteria,4 genera 11 species or varieties fungi and a virus have ice nucleation activity. Bacterial ice nuclei are proteins,named ice nucleating proteins, coded by ice nucleating genes.Ice nucleating genes of 11 species bacteria have been cloned, sequenced and expressed in Escherichia coli.Ice nucleation activity of ice protein is very weak,ice protein is decorated and assembled into powerful active ice nucleation by lipids and carbohydrates. Fungal ice nuclei are possibly protein, it differs from bacterial ice nuclei in some basic characteristics. Bacterial ice nucleation activity is influenced by some factors ,such as cell consistence, growth medium composition,incubation temperature,culture age and pH value, et al.Biological ice nuclei are important factors causing and increasing plant frost and freezing injury, and inducing plant disease. Treatments that reduce the numbers or the ice nucleation activity (or both) of ice nucleation active microorganisms on plant are effective in decreasing plant frost and freezing injury, and controlling plant disease.Biological ice nuclei are significant natural resources,it have been used in man made snow, refrigeration and diagnostic. It will be also wide prospective taking advantage of biological ice nuclei in preventing insect pests by accelerating insect body freezing.
出处
《林业科学研究》
CSCD
北大核心
2001年第4期446-454,共9页
Forest Research
基金
国家自然科学基金资助项目 (395 70 5 92 )
