英语翻译ReviewEnzymatic protein hydrolysis plays a major role in

英语翻译
Review
Enzymatic protein hydrolysis plays a major role in various physiological processes,including digestion,and is regulated by proteinase inhibitors.Inhibitors in foods and food ingredients can reduce the absorption of free amino acids,and can impair protein hydrolysis in industrial processes.However,inhibitors can be useful tools in pest control,in the prevention and treatment of diseases such as cancers and AIDS,and in the elimination of unwanted proteinase activity in food processes.Proteinase inhibitors are also useful biochemical tools for studying proteinase classes and specificities.This article discusses how proteinase inhibition is involved in some processes of current interest to food scientists and technologists.
Enzymatic protein hydrolysis is a major concern for biological scientists.The hydrolysis of proteins is catalyzed by peptide-bond-splitting enzymes (Box 1).Proteinases and peptidases are involved in the hydrolysis of protein during digestion,and have important roles in physiology and pathology.Enzymatic protein hydrolysis is controlled in several ways,including by the use of specific inhibitors (Box 2).Proteinase inhibition is a common process in nature.Proteinase-inhibitor interactions are involved in protein digestion,various physiological processes (e.g.blood coagulation,fibrinolysis,complement
activation and phagocytosis),pathological processes (e.g.cancers and hypertension) and infection
Another natural method of controlling proteinase activity is the synthesis of an inactive form of the enzyme,the zymogen.Zymogens are activated,usually by the action of another
proteinase,in the digestive system and also during regulatory physiological processes.When an enzyme is
in its active form,proteinase inhibition is an exquisite means of enzyme control in physiological processes,
which is achieved by highly specific inhibitors.The importance of the control of proteolytic activity by inhibitors in physiological processes is demonstrated by the fact that inhibitor molecules exceed 10% of the total protein in human plasma.
The fact that the control of proteolysis by inhibitors is so specific makes it a valuable tool in medicine,agriculture and food technology.The human immune deficiency virus proteinase,the digestive systems of crop pests,and fish muscle proteases are some examples of targets for study.Most organisms produce proteinase inhibitors as a means to control proteolytic processes.Some organisms store huge amounts of inhibitors,for example legume seeds and some leaves.This seems to be an evolutionary response to predation.
Inhibitors for digestive proteinases in food and feed
Some food ingredients contain so-called antinutritive factors:lectins,phenols,and other factors,including certain proteins that inhibit proteinases.The presence of proteinase inhibitors in living tissues seems to be a natural
regulatory process

综述
蛋白质的酶促水解在包括消化在内的众多生理学过程中扮演着重要的的角色,同时受蛋白酶抑制剂控制.在食物和食物成分中存在的抑制剂能减少对自由含氨基的酸的吸收,并且能妨害工业过程中的蛋白质水解.然而,在控制害虫,预防和治疗癌症及爱滋病等疾病以及限制食物程序中不希望的蛋白酶活性方面,抑制剂却可能是有用的工具.在研究蛋白酶的类别和特征上,蛋白酶抑制剂也是有用的生物化学工具.本文讨论了蛋白酶抑制剂是如何参与到当下食品科学家和工艺学家感兴趣的一些程序中的.
酶促蛋白质水解是生物学家主要关心的内容.蛋白质的水解由肽键裂解酶催化(表1).蛋白质酶和肽酶在消化过程中参与蛋白质的水解,而且具有重要的生理学和病理学作用.蛋白质酶促水解被几种途径控制,包括使用特殊的抑制剂(表2).蛋白酶的抑制是自然界中的一个寻常过程.蛋白酶-抑制剂相互作用参与着蛋白质的消化,各种生理学过程(例如：血液凝结,纤维蛋白溶解,补偿活动和噬菌作用),(例如：癌症和高血压) 和传染.自然界中另一个控制蛋白酶活性的方法是合成出酶的一种非活性形式,即酶原.在消化系统中和生理学控制过程中,酶原通常被另一种蛋白酶激活.当酶以它的活性形式存在时,蛋白酶抑制剂是生理学过程中一个酵控制的精细方法,可以通过具有高特异性的抑制剂实现.通过抑制剂控制生理学过程中蛋白质活性的重要性可以被如下事实证明：在人体血浆中,抑制剂分子超过蛋白质总量的10％.
事实表明,蛋白质水解的抑制剂控制是如此特异,这使它成为药物,农业和食品技术中一个有价值的工具.人类免疫缺乏病毒蛋白酶,农作物害虫的消化系统和鱼类肌肉蛋白酶就是研究目标的一些例子.大多数有机体生产蛋白酶抑制剂作为控制蛋白质水解过程的一个方法.一些有机体储存极大量的抑制剂,例如豆类种子和一些叶子.这似乎是对捕食的一个进化回应.
食物和饲养中水解蛋白酶抑制剂
一些食品成分中含有被称为反营养因子的物质:外源凝集素,酚及其他因子,包括抑制蛋白酶的特定蛋白质.蛋白酶抑制剂在活体组织中的存在似乎是一个自然控制过程.