{"title":"酿酒酵母转化酶动力学性质的生化研究","authors":"K. A. Salhen","doi":"10.37375/sjfssu.v2i2.75","DOIUrl":null,"url":null,"abstract":"Invertases are enzymes that hydrolyze sucrose to produce an equimolar mixture of glucose and fructose, which is of interest for various industrial applications. The present study aimed to produce invertase by Saccharomyces cerevisiae isolated from Baker’s yeast and grape samples using the standardize technique. The enzyme activity was characterized with some parameters like pH, temperature, metal ions, kinetic parameters and inhibitors (fructose, glucose and copper (II) sulfate). Spectrophotometric methods were used to study enzyme kinetics and to determine the factors affecting enzyme activity. The optimum activity was recorded at 55˚C for both invertases. The optimum activity was at pH 6.0 for Baker’s yeast invertase and at pH 10 for grape invertase. From Lineweaver-Burk Plot, Vmax was found to be 24.39 ± 2.44 nmol/min/mg protein and the Km approximately 0.860 ± 0.04 mM for Baker's yeast invertase but in case of grape invertase, Vmax was 23.25 ± 3.14 nmol/min/mg protein and the Km approximately1.243 ± 0.07 mM. Enzyme activity was increased in the presence of 5 mM Ca+2 ions for Baker’s yeast, whereas showed the maximum activity at 5 mM Mg+2 ions in case of grape fruit invertase. Using sucrose as substrate, the Kcat, Kcat/Km and Ks values were 0.28 ± 0.02 min-1, 0.325 ± 0.03 mM-1 min-1 and 27.03 ± 5.24 ml/min/mg protein for Baker’s yeast invertase activity, whereas were 0.56 ± 0.008 min-1, 0.045 ± 0.003 mM-1 min-1 and 24.39 ± 7.11 ml/min/mg protein for grape invertase values. In conclusion, the S. cerevisiae isolated from grape fruits was more potent for invertase production in comparable with that isolated from Baker’s yeast.","PeriodicalId":135432,"journal":{"name":"Scientific Journal for the Faculty of Science-Sirte University","volume":null,"pages":null},"PeriodicalIF":0.0000,"publicationDate":"2022-10-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Biochemical Study on the Kinetic Properties of the Invertase Produced by Saccharomyces Cerevisiae\",\"authors\":\"K. A. Salhen\",\"doi\":\"10.37375/sjfssu.v2i2.75\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"Invertases are enzymes that hydrolyze sucrose to produce an equimolar mixture of glucose and fructose, which is of interest for various industrial applications. The present study aimed to produce invertase by Saccharomyces cerevisiae isolated from Baker’s yeast and grape samples using the standardize technique. The enzyme activity was characterized with some parameters like pH, temperature, metal ions, kinetic parameters and inhibitors (fructose, glucose and copper (II) sulfate). Spectrophotometric methods were used to study enzyme kinetics and to determine the factors affecting enzyme activity. The optimum activity was recorded at 55˚C for both invertases. The optimum activity was at pH 6.0 for Baker’s yeast invertase and at pH 10 for grape invertase. From Lineweaver-Burk Plot, Vmax was found to be 24.39 ± 2.44 nmol/min/mg protein and the Km approximately 0.860 ± 0.04 mM for Baker's yeast invertase but in case of grape invertase, Vmax was 23.25 ± 3.14 nmol/min/mg protein and the Km approximately1.243 ± 0.07 mM. Enzyme activity was increased in the presence of 5 mM Ca+2 ions for Baker’s yeast, whereas showed the maximum activity at 5 mM Mg+2 ions in case of grape fruit invertase. Using sucrose as substrate, the Kcat, Kcat/Km and Ks values were 0.28 ± 0.02 min-1, 0.325 ± 0.03 mM-1 min-1 and 27.03 ± 5.24 ml/min/mg protein for Baker’s yeast invertase activity, whereas were 0.56 ± 0.008 min-1, 0.045 ± 0.003 mM-1 min-1 and 24.39 ± 7.11 ml/min/mg protein for grape invertase values. In conclusion, the S. cerevisiae isolated from grape fruits was more potent for invertase production in comparable with that isolated from Baker’s yeast.\",\"PeriodicalId\":135432,\"journal\":{\"name\":\"Scientific Journal for the Faculty of Science-Sirte University\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":0.0000,\"publicationDate\":\"2022-10-27\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Scientific Journal for the Faculty of Science-Sirte University\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://doi.org/10.37375/sjfssu.v2i2.75\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"\",\"JCRName\":\"\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Scientific Journal for the Faculty of Science-Sirte University","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.37375/sjfssu.v2i2.75","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 0
摘要
转化酶是一种酶,它可以水解蔗糖以产生葡萄糖和果糖的等摩尔混合物,这是各种工业应用的兴趣。本研究旨在利用标准化技术,从贝克酵母和葡萄样品中分离得到酿酒酵母生产转化酶。用pH、温度、金属离子、动力学参数和抑制剂(果糖、葡萄糖和硫酸铜)对酶活性进行了表征。采用分光光度法研究酶动力学,确定影响酶活性的因素。两种转化酶的最佳活性均在55℃。贝克酵母转化酶和葡萄转化酶的最佳活性分别为pH 6.0和pH 10。从lineweaverburk图中,贝克酵母转化酶的Vmax为24.39±2.44 nmol/min/mg蛋白,Km约为0.860±0.04 mM,而葡萄转化酶的Vmax为23.25±3.14 nmol/min/mg蛋白,Km约为1.243±0.07 mM。贝克酵母的酶活性在5 mM Ca+2离子存在时增加,而葡萄果实转化酶在5 mM mg +2离子存在时活性最大。以蔗糖为底物,贝克酵母转化酶活性的Kcat、Kcat/Km和Ks值分别为0.28±0.02 min-1、0.325±0.03 mM-1 min-1和27.03±5.24 ml/min/mg蛋白,而葡萄转化酶的Kcat、Kcat/Km和Ks值分别为0.56±0.008 min-1、0.045±0.003 mM-1 min-1和24.39±7.11 ml/min/mg蛋白。综上所述,从葡萄果实中分离出的酿酒葡萄球菌比从贝克酵母中分离出的酿酒葡萄球菌更能产生转化酶。
Biochemical Study on the Kinetic Properties of the Invertase Produced by Saccharomyces Cerevisiae
Invertases are enzymes that hydrolyze sucrose to produce an equimolar mixture of glucose and fructose, which is of interest for various industrial applications. The present study aimed to produce invertase by Saccharomyces cerevisiae isolated from Baker’s yeast and grape samples using the standardize technique. The enzyme activity was characterized with some parameters like pH, temperature, metal ions, kinetic parameters and inhibitors (fructose, glucose and copper (II) sulfate). Spectrophotometric methods were used to study enzyme kinetics and to determine the factors affecting enzyme activity. The optimum activity was recorded at 55˚C for both invertases. The optimum activity was at pH 6.0 for Baker’s yeast invertase and at pH 10 for grape invertase. From Lineweaver-Burk Plot, Vmax was found to be 24.39 ± 2.44 nmol/min/mg protein and the Km approximately 0.860 ± 0.04 mM for Baker's yeast invertase but in case of grape invertase, Vmax was 23.25 ± 3.14 nmol/min/mg protein and the Km approximately1.243 ± 0.07 mM. Enzyme activity was increased in the presence of 5 mM Ca+2 ions for Baker’s yeast, whereas showed the maximum activity at 5 mM Mg+2 ions in case of grape fruit invertase. Using sucrose as substrate, the Kcat, Kcat/Km and Ks values were 0.28 ± 0.02 min-1, 0.325 ± 0.03 mM-1 min-1 and 27.03 ± 5.24 ml/min/mg protein for Baker’s yeast invertase activity, whereas were 0.56 ± 0.008 min-1, 0.045 ± 0.003 mM-1 min-1 and 24.39 ± 7.11 ml/min/mg protein for grape invertase values. In conclusion, the S. cerevisiae isolated from grape fruits was more potent for invertase production in comparable with that isolated from Baker’s yeast.