{"title":"Heterologous expression, characterization, and application of recombinant thermostable α-amylase from Geobacillus sp. DS3 for porous starch production","authors":"","doi":"10.1016/j.bbrep.2024.101784","DOIUrl":null,"url":null,"abstract":"<div><p>Novel <em>Geobacillus</em> sp. DS3, isolated from the Sikidang Crater in Dieng, exhibits promising characteristics for industrial applications, particularly in thermostable α-amylase production. Recombinant technology was used to express thermostable α-amylase in <em>E. coli</em> BL21(DE3) to overcome high-temperature production challenges. The study aimed to express, purify, characterize, and explore potential applications of this novel enzyme. The enzyme was successfully expressed in <em>E. coli</em> BL21(DE3) at 18 °C for 20 h with 0.5 mM IPTG induction. Purification with Ni-NTA column yielded 69.23 % from the initial crude enzyme, with a 3.6-fold increase in specific activity. The enzyme has a molecular weight of ±70 kDa (±58 kDa enzyme+11 kDa SUMO protein). It exhibited activity over a wide temperature range (30–90 °C) and pH range (6–8), with optimal activity at 70 °C and pH 6 with great stability at 60 °C. Kinetic analysis revealed Km and Vmax values of 324.03 mg/ml and 36.5 U/mg, respectively, with dextrin as the preferred substrate without cofactor addition. As a metalloenzyme, it showed the best activity in the presence of Ca<sup>2+</sup>. The enzyme was used for porous starch production and successfully immobilized with chitosan, exhibiting improved thermal stability. After the fourth reuse, the immobilized enzyme maintained 62 % activity compared to the initial immobilization.</p></div>","PeriodicalId":8771,"journal":{"name":"Biochemistry and Biophysics Reports","volume":null,"pages":null},"PeriodicalIF":2.3000,"publicationDate":"2024-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S2405580824001481/pdfft?md5=76db7106b21992589630b0f9dbc7f5e8&pid=1-s2.0-S2405580824001481-main.pdf","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Biochemistry and Biophysics Reports","FirstCategoryId":"1085","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S2405580824001481","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"BIOCHEMISTRY & MOLECULAR BIOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
Novel Geobacillus sp. DS3, isolated from the Sikidang Crater in Dieng, exhibits promising characteristics for industrial applications, particularly in thermostable α-amylase production. Recombinant technology was used to express thermostable α-amylase in E. coli BL21(DE3) to overcome high-temperature production challenges. The study aimed to express, purify, characterize, and explore potential applications of this novel enzyme. The enzyme was successfully expressed in E. coli BL21(DE3) at 18 °C for 20 h with 0.5 mM IPTG induction. Purification with Ni-NTA column yielded 69.23 % from the initial crude enzyme, with a 3.6-fold increase in specific activity. The enzyme has a molecular weight of ±70 kDa (±58 kDa enzyme+11 kDa SUMO protein). It exhibited activity over a wide temperature range (30–90 °C) and pH range (6–8), with optimal activity at 70 °C and pH 6 with great stability at 60 °C. Kinetic analysis revealed Km and Vmax values of 324.03 mg/ml and 36.5 U/mg, respectively, with dextrin as the preferred substrate without cofactor addition. As a metalloenzyme, it showed the best activity in the presence of Ca2+. The enzyme was used for porous starch production and successfully immobilized with chitosan, exhibiting improved thermal stability. After the fourth reuse, the immobilized enzyme maintained 62 % activity compared to the initial immobilization.
期刊介绍:
Open access, online only, peer-reviewed international journal in the Life Sciences, established in 2014 Biochemistry and Biophysics Reports (BB Reports) publishes original research in all aspects of Biochemistry, Biophysics and related areas like Molecular and Cell Biology. BB Reports welcomes solid though more preliminary, descriptive and small scale results if they have the potential to stimulate and/or contribute to future research, leading to new insights or hypothesis. Primary criteria for acceptance is that the work is original, scientifically and technically sound and provides valuable knowledge to life sciences research. We strongly believe all results deserve to be published and documented for the advancement of science. BB Reports specifically appreciates receiving reports on: Negative results, Replication studies, Reanalysis of previous datasets.