Separation, Purification Of Mung Bean Aglycin And Aglycin Gene Cloning In Several Kinds Of Legumes

Aglycin is a bioactive polypeptide which was isolated and characterized from porcineintestines by Chen et al. The molecular is3742.3Da. Aglycin is consisted of37amino acidresidues with6cysteines at3,7,15,20,22and32of chain positions. It was named asaglycin due to its N-terminal alanine, and C-terminal glycine. Analysed and compared bythe method of bioinformatics. We found that there is a bioactive polypeptide extractedfrom pea seads which shows nearly identical primary structure with Aglycin, named PA1b.PA1b has homology of67percent with leginsulin separated from soybean. Besides, bothPA1b and leginsulin can bind to7S globulin which coexist with beans and has receptorprotein property, thus play a role in the developing process of beans. Interestingly, animalinsulin and Insulin-Like Growth Factor can bind to7S globulin. So, leginsulin, PA1b andAglycin represent a same kind of protein, which has conservative structure and highhomology. They are collectively called leginsulin.Aglycin not only has significant effects in the growth and development of plant, butalso can be an effective insecticide without any known toxicity to humans and mammalswhich can kill a series of pests like cereal weevils, becoming a new bioinsecticide of cropstorage and agricultural production.Besides, Aglycin can regulate glycometabolism on acertain degree. It can decrease the fasting blood glucose of mice with diabetes, improveInsulin sensitivity, thus normalizing the sugar tolerance and without any toxic andside-effect to animals. In a word, Aglycin is a small bioactive peptide which has importantfunction and significance to both plants, insects and animals. So the research of Aglycinshows significance especially. Mung bean seeds contain many proteins and are a majorprotein source for human beings. Mung bean contains various nutrients and phytoch-emicals and shows various nutritional and health-promoting functions. But nowadaysresearch about Aglycin focus on pea and soybeans. There are only a little research aboutmung bean Aglycin. So we hope we can pufiry mung bean Aglycin and lay a goodfoundation for the further study.The main purpose of this study is to separate and purify mung bean Aglycin based onthe experience of separation, purification of pea Aglycin in early days, to support the research about different functions among different leginsulins. But in the process ofpurification, we failed to separate and purify mung bean Aglycin, Which indicates thatdifference in distribution and tissue localization among different kinds of beans may leadto the difference in the methods of Aglycin purification. So, the next step we clonedAglycin gene of several kinds of Legumes and analyze homology among these Aglycingene, thus helping the fundamental research of leginsulin.In this study, the finished workare mainly the following aspects:1. Have a try and approach about separation and purification of mung bean Aglycinbased on the experience of separation, purification of pea Aglycin in early days.2. Clone the Aglycin gene of several kinds of Legumes.3. Compare and analyze the homology of Aglycin DNA sequence and amino acidsequence among different Legumes.Our results suggested that Although Aglycin of different Legumes have highhomology in both the DNA sequence and the amino acid sequence. The differences amongthem are still outstanding. These differences may cause the differences in distribution andtissue localization of Aglycin, thus leading to the difference in the methods of Aglycinpurification. So the method of Aglycin separation and purification among differentLegumes should be further optimized.