Deshuai Lou, Yangyang Cao, Hongtao Duan, Jun Tan, Binyan Li, Yuanjun Zhou, Dong Wang
{"title":"一种新型恒温 7α- 羟类固醇脱氢酶的特性。","authors":"Deshuai Lou, Yangyang Cao, Hongtao Duan, Jun Tan, Binyan Li, Yuanjun Zhou, Dong Wang","doi":"10.2174/0109298665279004231229100320","DOIUrl":null,"url":null,"abstract":"<p><strong>Background: </strong>7α-Hydroxysteroid dehydrogenase (7α-HSDH) plays a pivotal role in vivo in the biotransformation of secondary bile acids and has great potential in industrial biosynthesis due to its broad substrate specificity. In this study, we expressed and characterized a novel thermostable 7α-HSDH (named Sa 7α-HSDH).</p><p><strong>Methods: </strong>The DNA sequence was derived from the black bear gut microbiome metagenomic sequencing data, and the coding sequence of Sa 7α-HSDH was chemically synthesized. The heterologous expression of the enzyme was carried out using the pGEX-6p-1 vector. Subsequently, the activity of the purified enzyme was studied by measuring the absorbance change at 340 nm. Finally, the three-dimensional structure was predicted with AlphaFold2.</p><p><strong>Results: </strong>Coenzyme screening results confirmed it to be NAD(H) dependent. Substrate specificity test revealed that Sa 7α-HSDH could catalyze taurochenodeoxycholic acid (TCDCA) with catalytic efficiency (k<sub>cat</sub>/K<sub>m</sub>) 3.81 S-1 mM-1. The optimum temperature of Sa 7α-HSDH was measured to be 75°C, confirming that it belongs to thermophilic enzymes. Additionally, its thermostability was assessed using an accelerated stability test over 32 hours. The catalytic activity of Sa 7α-HSDH remained largely unchanged for the first 24 hours and retained over 90% of its functionality after 32 hours at 50°C. Sa 7α-HSDH exhibited maximal activity at pH 10. The effect of metal ions-K<sup>+</sup>, Na<sup>+</sup>, Mg<sup>2+</sup> and Cu<sup>2+</sup>-on the enzymatic activity of Sa 7α-HSDH was investigated. Only Mg<sup>2+</sup> was observed to enhance the enzyme's activity by 27% at a concentration of 300 mM. Neither K<sup>+</sup> nor Na+ had a significant influence on activity. Only Cu<sup>2+</sup> was found to reduce enzyme activity.</p><p><strong>Conclusion: </strong>We characterized the thermostable 7α-HSDH, which provides a promising biocatalyst for bioconversion of steroids at high reaction temperatures.</p>","PeriodicalId":20736,"journal":{"name":"Protein and Peptide Letters","volume":null,"pages":null},"PeriodicalIF":1.0000,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Characterization of a Novel Thermostable 7α-Hydroxysteroid Dehydrogenase.\",\"authors\":\"Deshuai Lou, Yangyang Cao, Hongtao Duan, Jun Tan, Binyan Li, Yuanjun Zhou, Dong Wang\",\"doi\":\"10.2174/0109298665279004231229100320\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p><strong>Background: </strong>7α-Hydroxysteroid dehydrogenase (7α-HSDH) plays a pivotal role in vivo in the biotransformation of secondary bile acids and has great potential in industrial biosynthesis due to its broad substrate specificity. In this study, we expressed and characterized a novel thermostable 7α-HSDH (named Sa 7α-HSDH).</p><p><strong>Methods: </strong>The DNA sequence was derived from the black bear gut microbiome metagenomic sequencing data, and the coding sequence of Sa 7α-HSDH was chemically synthesized. The heterologous expression of the enzyme was carried out using the pGEX-6p-1 vector. Subsequently, the activity of the purified enzyme was studied by measuring the absorbance change at 340 nm. Finally, the three-dimensional structure was predicted with AlphaFold2.</p><p><strong>Results: </strong>Coenzyme screening results confirmed it to be NAD(H) dependent. Substrate specificity test revealed that Sa 7α-HSDH could catalyze taurochenodeoxycholic acid (TCDCA) with catalytic efficiency (k<sub>cat</sub>/K<sub>m</sub>) 3.81 S-1 mM-1. The optimum temperature of Sa 7α-HSDH was measured to be 75°C, confirming that it belongs to thermophilic enzymes. Additionally, its thermostability was assessed using an accelerated stability test over 32 hours. The catalytic activity of Sa 7α-HSDH remained largely unchanged for the first 24 hours and retained over 90% of its functionality after 32 hours at 50°C. Sa 7α-HSDH exhibited maximal activity at pH 10. The effect of metal ions-K<sup>+</sup>, Na<sup>+</sup>, Mg<sup>2+</sup> and Cu<sup>2+</sup>-on the enzymatic activity of Sa 7α-HSDH was investigated. Only Mg<sup>2+</sup> was observed to enhance the enzyme's activity by 27% at a concentration of 300 mM. Neither K<sup>+</sup> nor Na+ had a significant influence on activity. Only Cu<sup>2+</sup> was found to reduce enzyme activity.</p><p><strong>Conclusion: </strong>We characterized the thermostable 7α-HSDH, which provides a promising biocatalyst for bioconversion of steroids at high reaction temperatures.</p>\",\"PeriodicalId\":20736,\"journal\":{\"name\":\"Protein and Peptide Letters\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":1.0000,\"publicationDate\":\"2024-01-01\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Protein and Peptide Letters\",\"FirstCategoryId\":\"99\",\"ListUrlMain\":\"https://doi.org/10.2174/0109298665279004231229100320\",\"RegionNum\":4,\"RegionCategory\":\"生物学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q4\",\"JCRName\":\"BIOCHEMISTRY & MOLECULAR BIOLOGY\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Protein and Peptide Letters","FirstCategoryId":"99","ListUrlMain":"https://doi.org/10.2174/0109298665279004231229100320","RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q4","JCRName":"BIOCHEMISTRY & MOLECULAR BIOLOGY","Score":null,"Total":0}
Characterization of a Novel Thermostable 7α-Hydroxysteroid Dehydrogenase.
Background: 7α-Hydroxysteroid dehydrogenase (7α-HSDH) plays a pivotal role in vivo in the biotransformation of secondary bile acids and has great potential in industrial biosynthesis due to its broad substrate specificity. In this study, we expressed and characterized a novel thermostable 7α-HSDH (named Sa 7α-HSDH).
Methods: The DNA sequence was derived from the black bear gut microbiome metagenomic sequencing data, and the coding sequence of Sa 7α-HSDH was chemically synthesized. The heterologous expression of the enzyme was carried out using the pGEX-6p-1 vector. Subsequently, the activity of the purified enzyme was studied by measuring the absorbance change at 340 nm. Finally, the three-dimensional structure was predicted with AlphaFold2.
Results: Coenzyme screening results confirmed it to be NAD(H) dependent. Substrate specificity test revealed that Sa 7α-HSDH could catalyze taurochenodeoxycholic acid (TCDCA) with catalytic efficiency (kcat/Km) 3.81 S-1 mM-1. The optimum temperature of Sa 7α-HSDH was measured to be 75°C, confirming that it belongs to thermophilic enzymes. Additionally, its thermostability was assessed using an accelerated stability test over 32 hours. The catalytic activity of Sa 7α-HSDH remained largely unchanged for the first 24 hours and retained over 90% of its functionality after 32 hours at 50°C. Sa 7α-HSDH exhibited maximal activity at pH 10. The effect of metal ions-K+, Na+, Mg2+ and Cu2+-on the enzymatic activity of Sa 7α-HSDH was investigated. Only Mg2+ was observed to enhance the enzyme's activity by 27% at a concentration of 300 mM. Neither K+ nor Na+ had a significant influence on activity. Only Cu2+ was found to reduce enzyme activity.
Conclusion: We characterized the thermostable 7α-HSDH, which provides a promising biocatalyst for bioconversion of steroids at high reaction temperatures.
期刊介绍:
Protein & Peptide Letters publishes letters, original research papers, mini-reviews and guest edited issues in all important aspects of protein and peptide research, including structural studies, advances in recombinant expression, function, synthesis, enzymology, immunology, molecular modeling, and drug design. Manuscripts must have a significant element of novelty, timeliness and urgency that merit rapid publication. Reports of crystallization and preliminary structure determination of biologically important proteins are considered only if they include significant new approaches or deal with proteins of immediate importance, and preliminary structure determinations of biologically important proteins. Purely theoretical/review papers should provide new insight into the principles of protein/peptide structure and function. Manuscripts describing computational work should include some experimental data to provide confirmation of the results of calculations.
Protein & Peptide Letters focuses on:
Structure Studies
Advances in Recombinant Expression
Drug Design
Chemical Synthesis
Function
Pharmacology
Enzymology
Conformational Analysis
Immunology
Biotechnology
Protein Engineering
Protein Folding
Sequencing
Molecular Recognition
Purification and Analysis