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Yin J, Liu Y, He D, Li P, Qiao M, Luo H, Qu X, Mei S, Wu Y, Sun Y, Gan F, Tang B, Tang XF. A TrmBL2-like transcription factor mediates the growth phase-dependent expression of halolysin SptA in a concentration-dependent manner in Natrinema gari J7-2. Appl Environ Microbiol 2024:e0074124. [PMID: 38953660 DOI: 10.1128/aem.00741-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2024] [Accepted: 06/08/2024] [Indexed: 07/04/2024] Open
Abstract
To cope with a high-salinity environment, haloarchaea generally employ the twin-arginine translocation (Tat) pathway to transport secretory proteins across the cytoplasm membrane in a folded state, including Tat-dependent extracellular subtilases (halolysins) capable of autocatalytic activation. Some halolysins, such as SptA of Natrinema gari J7-2, are produced at late-log phase to prevent premature enzyme activation and proteolytic damage of cellular proteins in haloarchaea; however, the regulation mechanism for growth phase-dependent expression of halolysins remains largely unknown. In this study, a DNA-protein pull-down assay was performed to identify the proteins binding to the 5'-flanking sequence of sptA encoding halolysin SptA in strain J7-2, revealing a TrmBL2-like transcription factor (NgTrmBL2). The ΔtrmBL2 mutant of strain J7-2 showed a sharp decrease in the production of SptA, suggesting that NgTrmBL2 positively regulates sptA expression. The purified recombinant NgTrmBL2 mainly existed as a dimer although monomeric and higher-order oligomeric forms were detected by native-PAGE analysis. The results of electrophoretic mobility shift assays (EMSAs) showed that NgTrmBL2 binds to the 5'-flanking sequence of sptA in a non-specific and concentration-dependent manner and exhibits an increased DNA-binding affinity with the increase in KCl concentration. Moreover, we found that a distal cis-regulatory element embedded in the neighboring upstream gene negatively regulates trmBL2 expression and thus participates in the growth phase-dependent biosynthesis of halolysin SptA. IMPORTANCE Extracellular proteases play important roles in nutrient metabolism, processing of functional proteins, and antagonism of haloarchaea, but no transcription factor involved in regulating the expression of haloaechaeal extracellular protease has been reported yet. Here we report that a TrmBL2-like transcription factor (NgTrmBL2) mediates the growth phase-dependent expression of an extracellular protease, halolysin SptA, of haloarchaeon Natrinema gari J7-2. In contrast to its hyperthermophilic archaeal homologs, which are generally considered to be global transcription repressors, NgTrmBL2 functions as a positive regulator for sptA expression. This study provides new clues about the transcriptional regulation mechanism of extracellular protease in haloarchaea and the functional diversity of archaeal TrmBL2.
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Affiliation(s)
- Jing Yin
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan, China
| | - Yang Liu
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan, China
| | - Dan He
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan, China
| | - Ping Li
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan, China
| | - Mengting Qiao
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan, China
| | - Hongyi Luo
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan, China
| | - Xiaoyi Qu
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan, China
| | - Sha Mei
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan, China
| | - Yi Wu
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan, China
| | - Yiqi Sun
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan, China
| | - Fei Gan
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan, China
- Cooperative Innovation Center of Industrial Fermentation (Ministry of Education & Hubei Province), Wuhan, China
| | - Bing Tang
- State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan, China
- Cooperative Innovation Center of Industrial Fermentation (Ministry of Education & Hubei Province), Wuhan, China
| | - Xiao-Feng Tang
- Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan, China
- Cooperative Innovation Center of Industrial Fermentation (Ministry of Education & Hubei Province), Wuhan, China
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Hong T, Pan R, Ke J, Luo Y, Hao Y, Chen L, Tu D, Dai Y, Chen T, Chen S. Expression, purification, and enzymatic characterization of an extracellular protease from Halococcus salifodinae. Braz J Microbiol 2023; 54:2689-2703. [PMID: 37661213 PMCID: PMC10689711 DOI: 10.1007/s42770-023-01114-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2023] [Accepted: 08/24/2023] [Indexed: 09/05/2023] Open
Abstract
Extracellular proteases from halophilic archaea displays increased enzymatic activities in hypersaline environment. In this study, an extracellular protease-coding gene, hly34, from the haloarchaeal strain Halococcus salifodinae PRR34, was obtained through homologous search. The protease activity produced by this strain at 20% NaCl, 42 °C, and pH 7.0 was 32.5 ± 0.5 (U·mL-1). The codon-optimized hly34 which is specific for Escherichia coli can be expressed in E. coli instead of native hly34. It exhibits proteolytic activity under a wide range of low- or high-salt concentrations, slightly acidic or alkaline conditions, and slightly higher temperatures. The Hly34 presented the highest proteolytic activity at 50 °C, pH 9.0, and 0-1 M NaCl. It was found that the Hly34 showed a higher enzyme activity under low-salt conditions. Hly34 has good stability at different NaCl concentrations (1-4 M) and pH (6.0-10.0), as well as good tolerance to some metal ions. However, at 60 °C, the stability is reduced. It has a good tolerance to some metal ions. The proteolytic activity was completely inhibited by phenylmethanesulfonyl fluoride, suggesting that the Hly34 is a serine protease. This study further deepens our understanding of haloarchaeal extracellular protease, most of which found in halophilic archaea are classified as serine proteases. These proteases exhibit a certain level of alkaline resistance and moderate heat resistance, and they may emerge with higher activity under low-salt conditions than high-salt conditions. The protease Hly34 is capable of degrading a number of proteins, including substrate proteins, such as azocasein, whey protein and casein. It has promising applications in industrial production.
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Affiliation(s)
- Tao Hong
- College of Life Sciences, Anhui Normal University, Wuhu, 241000, China
| | - Ruru Pan
- College of Life Sciences, Anhui Normal University, Wuhu, 241000, China
| | - Juntao Ke
- College of Life Sciences, Anhui Normal University, Wuhu, 241000, China
| | - Yuqing Luo
- College of Life Sciences, Anhui Normal University, Wuhu, 241000, China
| | - Yuling Hao
- College of Life Sciences, Anhui Normal University, Wuhu, 241000, China
| | - Liangzhong Chen
- College of Life Sciences, Anhui Normal University, Wuhu, 241000, China
| | - Demei Tu
- College of Life Sciences, Anhui Normal University, Wuhu, 241000, China
| | - Yongpei Dai
- College of Life Sciences, Anhui Normal University, Wuhu, 241000, China
| | - Tingting Chen
- College of Life Sciences, Anhui Normal University, Wuhu, 241000, China
| | - Shaoxing Chen
- College of Life Sciences, Anhui Normal University, Wuhu, 241000, China.
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 10010, China.
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Yao H, Liu S, Liu T, Ren D, Zhou Z, Yang Q, Mao J. Microbial-derived salt-tolerant proteases and their applications in high-salt traditional soybean fermented foods: a review. BIORESOUR BIOPROCESS 2023; 10:82. [PMID: 38647906 PMCID: PMC10992980 DOI: 10.1186/s40643-023-00704-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2023] [Accepted: 10/31/2023] [Indexed: 04/25/2024] Open
Abstract
Different microorganisms can produce different proteases, which can adapt to different industrial requirements such as pH, temperature, and pressure. Salt-tolerant proteases (STPs) from microorganisms exhibit higher salt tolerance, wider adaptability, and more efficient catalytic ability under extreme conditions compared to conventional proteases. These unique enzymes hold great promise for applications in various industries including food, medicine, environmental protection, agriculture, detergents, dyes, and others. Scientific studies on microbial-derived STPs have been widely reported, but there has been little systematic review of microbial-derived STPs and their application in high-salt conventional soybean fermentable foods. This review presents the STP-producing microbial species and their selection methods, and summarizes and analyzes the salt tolerance mechanisms of the microorganisms. It also outlines various techniques for the isolation and purification of STPs from microorganisms and discusses the salt tolerance mechanisms of STPs. Furthermore, this review demonstrates the contribution of modern biotechnology in the screening of novel microbial-derived STPs and their improvement in salt tolerance. It highlights the potential applications and commercial value of salt-tolerant microorganisms and STPs in high-salt traditional soy fermented foods. The review ends with concluding remarks on the challenges and future directions for microbial-derived STPs. This review provides valuable insights into the separation, purification, performance enhancement, and application of microbial-derived STPs in traditional fermented foods.
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Affiliation(s)
- Hongli Yao
- National Engineering Research Center of Cereal Fermentation and Food Biomanufacturing, School of Food Science and Technology, Jiangnan University, Wuxi, 214122, Jiangsu, China
- Jiangsu Provincial Engineering Research Center for Bioactive Product Processing Technology, Jiangnan University, Wuxi, 214122, Jiangsu, China
- Department of Biology and Food Engineering, Bozhou University, Bozhou, 236800, Anhui, China
| | - Shuangping Liu
- National Engineering Research Center of Cereal Fermentation and Food Biomanufacturing, School of Food Science and Technology, Jiangnan University, Wuxi, 214122, Jiangsu, China
- Southern Marine Science and Engineering Guangdong Laboratory, Guangzhou, 511458, Guangdong, China
- Jiangsu Provincial Engineering Research Center for Bioactive Product Processing Technology, Jiangnan University, Wuxi, 214122, Jiangsu, China
- Jiangnan University (Shaoxing) Industrial Technology Research Institute, Shaoxing, 31200, Zhejiang, China
- National Engineering Research Center of Huangjiu, Zhejiang Guyuelongshan Shaoxing Wine CO., LTD, Shaoxing, 646000, Zhejiang, China
| | - Tiantian Liu
- National Engineering Research Center of Cereal Fermentation and Food Biomanufacturing, School of Food Science and Technology, Jiangnan University, Wuxi, 214122, Jiangsu, China
- Jiangsu Provincial Engineering Research Center for Bioactive Product Processing Technology, Jiangnan University, Wuxi, 214122, Jiangsu, China
- Jiangnan University (Shaoxing) Industrial Technology Research Institute, Shaoxing, 31200, Zhejiang, China
- National Engineering Research Center of Huangjiu, Zhejiang Guyuelongshan Shaoxing Wine CO., LTD, Shaoxing, 646000, Zhejiang, China
| | - Dongliang Ren
- National Engineering Research Center of Cereal Fermentation and Food Biomanufacturing, School of Food Science and Technology, Jiangnan University, Wuxi, 214122, Jiangsu, China
- Jiangsu Provincial Engineering Research Center for Bioactive Product Processing Technology, Jiangnan University, Wuxi, 214122, Jiangsu, China
| | - Zhilei Zhou
- National Engineering Research Center of Cereal Fermentation and Food Biomanufacturing, School of Food Science and Technology, Jiangnan University, Wuxi, 214122, Jiangsu, China
- Southern Marine Science and Engineering Guangdong Laboratory, Guangzhou, 511458, Guangdong, China
- Jiangsu Provincial Engineering Research Center for Bioactive Product Processing Technology, Jiangnan University, Wuxi, 214122, Jiangsu, China
- Jiangnan University (Shaoxing) Industrial Technology Research Institute, Shaoxing, 31200, Zhejiang, China
- National Engineering Research Center of Huangjiu, Zhejiang Guyuelongshan Shaoxing Wine CO., LTD, Shaoxing, 646000, Zhejiang, China
| | - Qilin Yang
- National Engineering Research Center of Cereal Fermentation and Food Biomanufacturing, School of Food Science and Technology, Jiangnan University, Wuxi, 214122, Jiangsu, China
- Jiangsu Provincial Engineering Research Center for Bioactive Product Processing Technology, Jiangnan University, Wuxi, 214122, Jiangsu, China
| | - Jian Mao
- National Engineering Research Center of Cereal Fermentation and Food Biomanufacturing, School of Food Science and Technology, Jiangnan University, Wuxi, 214122, Jiangsu, China.
- Southern Marine Science and Engineering Guangdong Laboratory, Guangzhou, 511458, Guangdong, China.
- Jiangsu Provincial Engineering Research Center for Bioactive Product Processing Technology, Jiangnan University, Wuxi, 214122, Jiangsu, China.
- Jiangnan University (Shaoxing) Industrial Technology Research Institute, Shaoxing, 31200, Zhejiang, China.
- National Engineering Research Center of Huangjiu, Zhejiang Guyuelongshan Shaoxing Wine CO., LTD, Shaoxing, 646000, Zhejiang, China.
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Nwankwo C, Hou J, Cui HL. Extracellular proteases from halophiles: diversity and application challenges. Appl Microbiol Biotechnol 2023; 107:5923-5934. [PMID: 37566160 DOI: 10.1007/s00253-023-12721-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2023] [Revised: 07/26/2023] [Accepted: 08/01/2023] [Indexed: 08/12/2023]
Abstract
Halophilic extracellular proteases offer promising application in various fields. Information on these prominent proteins including the synthesizing organisms, biochemical properties, domain organisation, purification, and application challenges has never been covered in recent reviews. Although extracellular proteases from bacteria pioneered the study of proteases in halophiles, progress is being made in proteases from halophilic archaea. Recent advances in extracellular proteases from archaea revealed that archaeal proteases are more robust and applicable. Extracellular proteases are composed of domains that determine their mechanisms of action. The intriguing domain structure of halophilic extracellular proteases consists of N-terminal domain, catalytic domain, and C-terminal extension. The role of C-terminal domains varies among different organisms. A high diversity of C-terminal domains would endow the proteases with diverse functions. With the development of genomics, culture-independent methods involving heterologous expression, affinity chromatography, and in vitro refolding are deployed with few challenges on purification and presenting novel research opportunities. Halophilic extracellular proteases have demonstrated remarkable potentials in industries such as detergent, leather, peptide synthesis, and biodegradation, with desirable properties and ability to withstand harsh industrial processes. KEY POINTS: • Halophilic extracellular proteases have robust properties suitable for applications. • A high diversity of C-terminal domains may endow proteases with diverse properties. • Novel protease extraction methods present novel application opportunities.
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Affiliation(s)
- Chidiebele Nwankwo
- School of Food and Biological Engineering, Jiangsu University, 301 Xuefu Road, Jingkou District, Zhenjiang, 212013, Jiangsu, People's Republic of China
- Natural Sciences Unit, School of General Studies, University of Nigeria, Nsukka, 410002, Enugu State, Nigeria
- Department of Microbiology, Faculty of Biological Sciences, University of Nigeria, Nsukka, 410002, Enugu State, Nigeria
| | - Jing Hou
- School of Food and Biological Engineering, Jiangsu University, 301 Xuefu Road, Jingkou District, Zhenjiang, 212013, Jiangsu, People's Republic of China.
| | - Heng-Lin Cui
- School of Food and Biological Engineering, Jiangsu University, 301 Xuefu Road, Jingkou District, Zhenjiang, 212013, Jiangsu, People's Republic of China.
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Gaonkar SK, Alvares JJ, Furtado IJ. Recent advances in the production, properties and applications of haloextremozymes protease and lipase from haloarchaea. World J Microbiol Biotechnol 2023; 39:322. [PMID: 37755613 DOI: 10.1007/s11274-023-03779-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2023] [Accepted: 09/22/2023] [Indexed: 09/28/2023]
Abstract
Proteases and lipases are significant groups of enzymes for commercialization at the global level. Earlier, the industries depended on mesophilic proteases and lipases, which remain nonfunctional under extreme conditions. The discovery of extremophilic microorganisms, especially those belonging to haloarchaea, paved a new reserve of industrially competent extremozymes. Haloarchaea or halophilic archaea are polyextremophiles of domain Archaea that grow at high salinity, elevated temperature, pH range (pH 6-12), and low aw. Interestingly, haloarchaeal proteolytic and lipolytic enzymes also perform their catalytic function in the presence of 4-5 M NaCl in vivo and in vitro. Also, they are of great interest to study due to their capacity to function and are active at elevated temperatures, tolerance to pH extremes, and in non-aqueous media. In recent years, advances have been achieved in various aspects of genomic/molecular expression methods involving homologous and heterologous processes for the overproduction of these extremozymes and their characterization from haloarchaea. A few protease and lipase extremozymes have been successfully expressed in prokaryotic systems, especially E.coli, and enzyme modification techniques have improved the catalytic properties of the recombinant enzymes. Further, in-silico methods are currently applied to elucidate the structural and functional features of salt-stable protease and lipase in haloarchaea. In this review, the production and purification methods, catalytic and biochemical properties and biotechnological applications of haloextremozymes proteases and lipases are summarized along with recent advancements in overproduction and characterization of these enzymes, concluding with the directions for further in-depth research on proteases and lipases from haloarchaea.
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Affiliation(s)
- Sanket K Gaonkar
- Microbiology Programme, School of Biological Sciences and Biotechnology, Goa University, Taleigao Plateau, Goa, 403206, India.
- Department of Microbiology, P.E.S's R.S.N College of Arts and Science, Farmagudi, Ponda-Goa, 403401, India.
| | - Jyothi Judith Alvares
- Microbiology Programme, School of Biological Sciences and Biotechnology, Goa University, Taleigao Plateau, Goa, 403206, India
| | - Irene J Furtado
- Microbiology Programme, School of Biological Sciences and Biotechnology, Goa University, Taleigao Plateau, Goa, 403206, India
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6
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Leng W, Wu X, Qi X, Liu H, Yuan L, Gao R. Systematic functional analysis and potential application of a serine protease from cold-adapted Planococcus bacterium. FOOD SCIENCE AND HUMAN WELLNESS 2023. [DOI: 10.1016/j.fshw.2023.02.025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/28/2023]
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Zhang S, Chen F, Ke J, Hao Y, Pan R, Hong T, Dai Y, Chen S. Hly176B, a low-salt tolerant halolysin from the haloarchaeon Haloarchaeobius sp. FL176. World J Microbiol Biotechnol 2023; 39:189. [PMID: 37157004 DOI: 10.1007/s11274-023-03632-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Accepted: 04/26/2023] [Indexed: 05/10/2023]
Abstract
Extracellular proteases of haloarchaea can adapt to high concentrations of NaCl and can find useful applications in industrial or biotechnology processes where hypersaline conditions are desired. The diversity of extracellular proteases produced by haloarchaea is largely unknown though the genomes of many species have been sequenced and are publicly available. In this study, a gene encoding the extracellular protease Hly176B from the haloarchaeon Haloarchaeobius sp. FL176 was cloned and expressed in Escherichia coli. A related gene homolog to hly176B, hly176A, from the same strain was also expressed in E.coli, but did not show any proteinase activity after the same renaturation process. Therefore, we focus on the enzymatic properties of the Hly176B. The catalytic triad Asp-His-Ser was confirmed via site-directed mutagenesis, indicating that Hly176B belongs to the class of serine proteases (halolysin). Unlike previously reported extracellular proteases from haloarchaea, the Hly176B remained active for a relatively long time in an almost salt-free solution. In addition, the Hly176B displayed prominent tolerance to some metal ions, surfactants and organic solvents, and exerts its highest enzyme activity at 40 °C, pH 8.0 and 0.5 M NaCl. Therefore, this study enriches our knowledge of extracellular proteases and expands their applications for various industrial uses.
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Affiliation(s)
- Shenao Zhang
- College of Life Sciences, Anhui Normal University, Wuhu, 241000, China
| | - Feilong Chen
- College of Life Sciences, Anhui Normal University, Wuhu, 241000, China
- Anhui Jiaotianxiang Biological Technology Co., Ltd, Xuancheng, 242000, China
| | - Juntao Ke
- College of Life Sciences, Anhui Normal University, Wuhu, 241000, China
| | - Yuling Hao
- College of Life Sciences, Anhui Normal University, Wuhu, 241000, China
| | - Ruru Pan
- College of Life Sciences, Anhui Normal University, Wuhu, 241000, China
| | - Tao Hong
- College of Life Sciences, Anhui Normal University, Wuhu, 241000, China
| | - Yongpei Dai
- College of Life Sciences, Anhui Normal University, Wuhu, 241000, China
| | - Shaoxing Chen
- College of Life Sciences, Anhui Normal University, Wuhu, 241000, China.
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 10010, China.
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Comparison of Reduced-Salt Fish Sauces Produced Under Pressurized Carbon Dioxide Treatment From Sardinops melanostictus, Trachurus japonicus, Konosirus punctatus, Odontamblyopus lacepedii, and Their Mixture. FOOD BIOPROCESS TECH 2022. [DOI: 10.1007/s11947-022-02920-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Hou J, Li SY, Zhao YJ, Cui HL. A novel halolysin without C-terminal extension from an extremely halophilic archaeon. Appl Microbiol Biotechnol 2022; 106:3009-3019. [PMID: 35435453 DOI: 10.1007/s00253-022-11903-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Revised: 03/28/2022] [Accepted: 03/29/2022] [Indexed: 11/29/2022]
Abstract
Halolysins are extracellular proteases secreted by halophilic archaea for nutritional purposes. They bear great application potentials in various industries. Yet the diversity of halolysins remains underexplored. In this study, a halolysin from the extremely halophilic archaeon Haladaptatus sp. DYF46 (HlyHap) was identified to be a novel type of halolysin without C-terminal extension (CTE). Addition of the CTE of a halolysin from Halococcus salifodinae to HlyHap did not significantly affect its extracellular proteolytic activity. Mature HlyHap was generated from recombinant HlyHap precursor by high-affinity column refolding. HlyHap displayed optimal activity at 0.25-0.50 M NaCl, 45 °C and pH 8.5-9.0. Interestingly, HlyHap preferred a low salinity and was stable in a broad range of salinity, albeit from an extremely halophilic archaeon. Ca2+ and Mg2+ significantly promoted HlyHap activity. HlyHap activity was stable with organic solvents and detergents. The Km and Vmax values of HlyHap against azocasein were 0.018 mM and 7,179 U/mg, and those against succinyl-Ala-Ala-Pro-Phe-pNA were 0.32 mM and 3×106 μmol/min/μg, respectively. The unusual traits of HlyHap, a novel type of halolysin without CTE, may endow it with strong potential for various industrial uses, such as biocatalysis in fluctuating salinities and aqueous-organic solvent. KEY POINTS: • This is the first report of a novel type of halolysin without C-terminal extension • HlyHap was obtained by heterologous expression and high-affinity column refolding • HlyHap exhibited good salinity tolerance.
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Affiliation(s)
- Jing Hou
- School of Food and Biological Engineering, Jiangsu University, 301 Xuefu Road, Jingkou District, Zhenjiang, 212013, Jiangsu, People's Republic of China
| | - Si-Ya Li
- School of Food and Biological Engineering, Jiangsu University, 301 Xuefu Road, Jingkou District, Zhenjiang, 212013, Jiangsu, People's Republic of China
| | - Yang-Jie Zhao
- School of Food and Biological Engineering, Jiangsu University, 301 Xuefu Road, Jingkou District, Zhenjiang, 212013, Jiangsu, People's Republic of China
| | - Heng-Lin Cui
- School of Food and Biological Engineering, Jiangsu University, 301 Xuefu Road, Jingkou District, Zhenjiang, 212013, Jiangsu, People's Republic of China.
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Sec-Dependent Secretion of Subtilase SptE in Haloarchaea Facilitates Its Proper Folding and Heterocatalytic Processing by Halolysin SptA Extracellularly. Appl Environ Microbiol 2022; 88:e0024622. [PMID: 35348390 DOI: 10.1128/aem.00246-22] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
In response to high-salt conditions, haloarchaea export most secretory proteins through the Tat pathway in folded states; however, it is unclear why some haloarchaeal proteins are still routed to the Sec pathway. SptE is an extracellular subtilase of Natrinema sp. strain J7-2. Here, we found that SptE precursor comprises a Sec signal peptide, an N-terminal propeptide, a catalytic domain, and a long C-terminal extension (CTE) containing seven domains (C1 to C7). SptE is produced extracellularly as a mature form (M180) in strain J7-2 and a proform (ΔS) in the ΔsptA mutant strain, indicating that halolysin SptA mediates the conversion of the secreted proform into M180. The proper folding of ΔS is more efficient in the presence of NaCl than KCl. ΔS requires SptA for cleavage of the N-terminal propeptide and C-terminal C6 and C7 domains to generate M180, accompanied by the appearance of autoprocessing product M120 lacking C5. At lower salinities or elevated temperatures, M180 and M120 could be autoprocessed into M90, which comprises the catalytic and C1 domains and has a higher activity than M180. When produced in Haloferax volcanii, SptE could be secreted as a properly folded proform, but its variant (TSptE) with a Tat signal peptide does not fold properly and suffers from severe proteolysis extracellularly; meanwhile, TSptE is more inclined to aggregate intracellularly than SptE. Systematic domain deletion analysis reveals that the long CTE is an important determinant for secretion of SptE via the Sec rather than Tat pathway to prevent enzyme aggregation before secretion. IMPORTANCE While Tat-dependent haloarchaeal subtilases (halolysins) have been extensively studied, the information about Sec-dependent subtilases of haloarchaea is limited. Our results demonstrate that proper maturation of Sec-dependent subtilase SptE of Natrinema sp. strain J7-2 depends on the action of halolysin SptA from the same strain, yielding multiple hetero- and autocatalytic mature forms. Moreover, we found that the different extra- and intracellular salt types (NaCl versus KCl) of haloarchaea and the long CTE are extrinsic and intrinsic factors crucial for routing SptE to the Sec rather than Tat pathway. This study provides new clues about the secretion and adaptation mechanisms of Sec substrates in haloarchaea.
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11
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Leng W, Gao R, Wu X, Zhou J, Sun Q, Yuan L. Genome sequencing of cold-adapted Planococcus bacterium isolated from traditional shrimp paste and protease identification. JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE 2021; 101:3225-3236. [PMID: 33222174 DOI: 10.1002/jsfa.10952] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2020] [Revised: 11/17/2020] [Accepted: 11/22/2020] [Indexed: 06/11/2023]
Abstract
BACKGROUND Psychrophiles have evolved to adapt to freezing environments, and cold-adapted enzymes from these organisms can maintain high catalytic activity at low temperature. The use of cold-adapted enzymes has great potential for the revolution of food and molecular biology industries. RESULTS In this study, four different strains producing protease were isolated from traditional fermented shrimp paste, one of which, named Planococcus maritimus XJ11 by 16S rRNA nucleotide sequence analysis, exhibited the largest protein hydrolysis clear zone surrounding the colonies. Meanwhile, the strain P. maritimus XJ11 was selected for further investigation because of its great adaptation to low temperature, low salinity and alkaline environment. The enzyme activity assay of P. maritimus XJ11 indicated that the optimum conditions for catalytic activity were pH 10.0 and 40 °C. Moreover, the enzyme also showed an increasing activity with temperatures from 10 to 40 °C and retained more than 67% activity of the maximum over a broad range of salinity (50-150 g L-1 ). Genome sequencing analysis revealed that strain XJ11 possessed one circular chromosome of 3 282 604 bp and one circular plasmid of 67 339 bp, with a total number of 3293 open reading frames (ORFs). Besides, 21 genes encoding protease, including three serine proteases, were identified through the NR database. CONCLUSION Cold-adapted bacterium P. maritimus XJ11 was capable of producing alkaline proteases with high catalytic efficiency at low or moderate temperatures. Furthermore, the favorable psychrophilic and enzymatic characters of strain P. maritimus XJ11 seem to have a promising potential for industrial application. © 2020 Society of Chemical Industry.
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Affiliation(s)
- Weijun Leng
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang, China
| | - Ruichang Gao
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang, China
| | - Xiaoyun Wu
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang, China
| | - Jing Zhou
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang, China
| | - Quancai Sun
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang, China
| | - Li Yuan
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang, China
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Hou J, Yin XM, Li Y, Han D, Lü B, Zhang JY, Cui HL. Biochemical characterization of a low salt-adapted extracellular protease from the extremely halophilic archaeon Halococcus salifodinae. Int J Biol Macromol 2021; 176:253-259. [PMID: 33592265 DOI: 10.1016/j.ijbiomac.2021.02.081] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Revised: 02/09/2021] [Accepted: 02/11/2021] [Indexed: 12/30/2022]
Abstract
Extracellular proteases from haloarchaea can expand the application fields of proteases. Exploring novel robust proteases is of great importance. An extracellular protease HlyA from Halococcus salifodinae was obtained by heterologous expression, affinity chromatography, in vitro refolding and gel filtration chromatography. Its activity was optimal at 45 °C, pH 9.0 and 1.5-2 M NaCl. Interestingly, although HlyA was from an extremely halophilic archaeon, it retained >75% of maximal activity in a broad NaCl concentration of 0.5-4 M. It displayed relatively stable activities over a wide range of temperature, pH and salinity. Thus, HlyA exhibited good temperature, pH and especially, salinity tolerance. Ca2+, Mg2+ and Sr2+ significantly enhanced the protease activity. HlyA activity was completely inhibited by phenylmethanesulfonyl fluoride (PMSF), suggesting it is a serine protease. HlyA showed good tolerance to some surfactants and organic solvents. The Km and Vmax values of HlyA for azocasein were calculated to be 0.72 mM and 21.98 U/μg, respectively. HlyA was able to effectively degrade several protein substrates, including bovine hemoglobin, casein and azocasein. Generally, HlyA from the extremely halophilic archaeon Hcc. salifodinae is an alkaliphilic and low salt-adapted halolysin with high activity, thus representing an attractive candidate for various industrial uses.
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Affiliation(s)
- Jing Hou
- School of Food and Biological Engineering, Jiangsu University, 301 Xuefu Road, Jingkou District, Zhenjiang 212013, Jiangsu, People's Republic of China
| | - Xue-Meng Yin
- School of Food and Biological Engineering, Jiangsu University, 301 Xuefu Road, Jingkou District, Zhenjiang 212013, Jiangsu, People's Republic of China
| | - Yang Li
- School of Food and Biological Engineering, Jiangsu University, 301 Xuefu Road, Jingkou District, Zhenjiang 212013, Jiangsu, People's Republic of China
| | - Dong Han
- School of Food and Biological Engineering, Jiangsu University, 301 Xuefu Road, Jingkou District, Zhenjiang 212013, Jiangsu, People's Republic of China
| | - Bu Lü
- School of Food and Biological Engineering, Jiangsu University, 301 Xuefu Road, Jingkou District, Zhenjiang 212013, Jiangsu, People's Republic of China
| | - Jia-Yi Zhang
- School of Food and Biological Engineering, Jiangsu University, 301 Xuefu Road, Jingkou District, Zhenjiang 212013, Jiangsu, People's Republic of China
| | - Heng-Lin Cui
- School of Food and Biological Engineering, Jiangsu University, 301 Xuefu Road, Jingkou District, Zhenjiang 212013, Jiangsu, People's Republic of China.
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