Mery S Waheeb, Walid F Elkhatib, Mahmoud A Yassien, Nadia A Hassouna
{"title":"优化热粘链霉菌株的恒温纤维素酶的生产和特性。","authors":"Mery S Waheeb, Walid F Elkhatib, Mahmoud A Yassien, Nadia A Hassouna","doi":"10.1186/s13568-024-01787-0","DOIUrl":null,"url":null,"abstract":"<p><p>A high cellulase-producing bacterial isolate TS4 was recovered from an Egyptian soil sample and identified using 16S rRNA gene sequencing as Streptomyces thermodiastaticus. One-factor-at-a-time (OFAT) preliminary studies were carried out to determine the key factors affecting cellulase production by S. thermodiastaticus and their optimum ranges. The initial pH of the medium, carboxymethyl cellulose (CMC), tryptone, and NaCl concentrations were further optimized using a response surface Central Composite design. Fermentation under optimized variables of initial pH 6.0, presence of CMC, tryptone, and NaCl at concentrations of 2%, 0.03%, and 0.12%, respectively, resulted in 3.24 fold increase in cellulase productivity (2023 U/L) as compared to that under basal conditions (625 U/L). Cellulase production was also improved with a 4 Kilogray (KGy) dosage of gamma radiation. In comparison to the wild-type strain under basal circumstances, S. thermodiastaticus produced 5.1 fold more cellulase after a combination of model-based optimization and gamma radiation mutation. Cellulase was partially purified using ammonium sulfate precipitation followed by dialysis. The resulting cellulase was 1.74 times purified and its specific activity was 4.21 U/mg. The molecular weight of cellulase is 63 kDa as indicated by SDS-PAGE and zymogram. Its maximum activity was achieved at 60 °C and pH 5.0. In addition, it showed outstanding thermo-tolerance as it could retain its full activity after a 12-h incubation at 90 °C.</p>","PeriodicalId":7537,"journal":{"name":"AMB Express","volume":"14 1","pages":"129"},"PeriodicalIF":3.5000,"publicationDate":"2024-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11582227/pdf/","citationCount":"0","resultStr":"{\"title\":\"Optimized production and characterization of a thermostable cellulase from Streptomyces thermodiastaticus strain.\",\"authors\":\"Mery S Waheeb, Walid F Elkhatib, Mahmoud A Yassien, Nadia A Hassouna\",\"doi\":\"10.1186/s13568-024-01787-0\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p><p>A high cellulase-producing bacterial isolate TS4 was recovered from an Egyptian soil sample and identified using 16S rRNA gene sequencing as Streptomyces thermodiastaticus. One-factor-at-a-time (OFAT) preliminary studies were carried out to determine the key factors affecting cellulase production by S. thermodiastaticus and their optimum ranges. The initial pH of the medium, carboxymethyl cellulose (CMC), tryptone, and NaCl concentrations were further optimized using a response surface Central Composite design. Fermentation under optimized variables of initial pH 6.0, presence of CMC, tryptone, and NaCl at concentrations of 2%, 0.03%, and 0.12%, respectively, resulted in 3.24 fold increase in cellulase productivity (2023 U/L) as compared to that under basal conditions (625 U/L). Cellulase production was also improved with a 4 Kilogray (KGy) dosage of gamma radiation. In comparison to the wild-type strain under basal circumstances, S. thermodiastaticus produced 5.1 fold more cellulase after a combination of model-based optimization and gamma radiation mutation. Cellulase was partially purified using ammonium sulfate precipitation followed by dialysis. The resulting cellulase was 1.74 times purified and its specific activity was 4.21 U/mg. The molecular weight of cellulase is 63 kDa as indicated by SDS-PAGE and zymogram. Its maximum activity was achieved at 60 °C and pH 5.0. In addition, it showed outstanding thermo-tolerance as it could retain its full activity after a 12-h incubation at 90 °C.</p>\",\"PeriodicalId\":7537,\"journal\":{\"name\":\"AMB Express\",\"volume\":\"14 1\",\"pages\":\"129\"},\"PeriodicalIF\":3.5000,\"publicationDate\":\"2024-11-21\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11582227/pdf/\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"AMB Express\",\"FirstCategoryId\":\"5\",\"ListUrlMain\":\"https://doi.org/10.1186/s13568-024-01787-0\",\"RegionNum\":3,\"RegionCategory\":\"生物学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q2\",\"JCRName\":\"BIOTECHNOLOGY & APPLIED MICROBIOLOGY\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"AMB Express","FirstCategoryId":"5","ListUrlMain":"https://doi.org/10.1186/s13568-024-01787-0","RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"BIOTECHNOLOGY & APPLIED MICROBIOLOGY","Score":null,"Total":0}
Optimized production and characterization of a thermostable cellulase from Streptomyces thermodiastaticus strain.
A high cellulase-producing bacterial isolate TS4 was recovered from an Egyptian soil sample and identified using 16S rRNA gene sequencing as Streptomyces thermodiastaticus. One-factor-at-a-time (OFAT) preliminary studies were carried out to determine the key factors affecting cellulase production by S. thermodiastaticus and their optimum ranges. The initial pH of the medium, carboxymethyl cellulose (CMC), tryptone, and NaCl concentrations were further optimized using a response surface Central Composite design. Fermentation under optimized variables of initial pH 6.0, presence of CMC, tryptone, and NaCl at concentrations of 2%, 0.03%, and 0.12%, respectively, resulted in 3.24 fold increase in cellulase productivity (2023 U/L) as compared to that under basal conditions (625 U/L). Cellulase production was also improved with a 4 Kilogray (KGy) dosage of gamma radiation. In comparison to the wild-type strain under basal circumstances, S. thermodiastaticus produced 5.1 fold more cellulase after a combination of model-based optimization and gamma radiation mutation. Cellulase was partially purified using ammonium sulfate precipitation followed by dialysis. The resulting cellulase was 1.74 times purified and its specific activity was 4.21 U/mg. The molecular weight of cellulase is 63 kDa as indicated by SDS-PAGE and zymogram. Its maximum activity was achieved at 60 °C and pH 5.0. In addition, it showed outstanding thermo-tolerance as it could retain its full activity after a 12-h incubation at 90 °C.
期刊介绍:
AMB Express is a high quality journal that brings together research in the area of Applied and Industrial Microbiology with a particular interest in ''White Biotechnology'' and ''Red Biotechnology''. The emphasis is on processes employing microorganisms, eukaryotic cell cultures or enzymes for the biosynthesis, transformation and degradation of compounds. This includes fine and bulk chemicals, polymeric compounds and enzymes or other proteins. Downstream processes are also considered. Integrated processes combining biochemical and chemical processes are also published.