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Sharma I, Gupta P, Kango N. Synthesis and characterization of keratinase laden green synthesized silver nanoparticles for valorization of feather keratin. Sci Rep 2023; 13:11608. [PMID: 37463953 DOI: 10.1038/s41598-023-38721-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2023] [Accepted: 07/13/2023] [Indexed: 07/20/2023] Open
Abstract
This study focuses on the efficient and cost-effective synthesis of silver nanoparticles (AgNPs) using plant extracts, which have versatile and non-toxic applications. The research objectives include synthesizing AgNPs from readily available plant extracts, optimizing their production and multi scale characterization, along with exploring their use for enzyme immobilization and mitigation of poultry feather waste. Among the plant extracts tested, the flower extract of Hibiscus rosa-sinensis (HF) showed the most potential for AgNP synthesis. The synthesis of HF-mediated AgNPs was optimized using response surface methodology (RSM) for efficient and environment friendly production. Additionally, the keratinase enzyme obtained from Bacillus sp. NCIM 5802 was covalently linked to AgNPs, forming a keratinase nanocomplex (KNC) whose biochemical properties were evaluated. The KNC demonstrated optimal activity at pH 10.0 and 60 °C and it displayed remarkable stability in the presence of various inhibitors, metal ions, surfactants, and detergents. Spectroscopic techniques such as FTIR, UV-visible, and X-ray diffraction (XRD) analysis were employed to investigate the formation of biogenic HF-AgNPs and KNC, confirming the presence of capping and stabilizing agents. The morphological characteristics of the synthesized AgNPs and KNC were determined using transmission electron microscopy (TEM) and particle size analysis. The study highlighted the antimicrobial, dye scavenging, and antioxidant properties of biogenic AgNPs and KNC, demonstrating their potential for various applications. Overall, this research showcases the effectiveness of plant extract-driven green synthesis of AgNPs and the successful development of keratinase-laden nanocomplexes, opening possibilities for their use in immobilizing industrial and commercial enzymes.
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Affiliation(s)
- Isha Sharma
- Department of Microbiology, Dr. Harisingh Gour Vishwavidyalaya (A Central University), Sagar, Madhya Pradesh, 470003, India
| | - Pranshi Gupta
- Department of Microbiology, Dr. Harisingh Gour Vishwavidyalaya (A Central University), Sagar, Madhya Pradesh, 470003, India
| | - Naveen Kango
- Department of Microbiology, Dr. Harisingh Gour Vishwavidyalaya (A Central University), Sagar, Madhya Pradesh, 470003, India.
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2
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Nadal-Molero F, Campos-Lopez A, Tur-Moya J, Martin-Cuadrado AB. Microbial community on industrial salty bovine hides: From the slaughterhouse to the salting. Syst Appl Microbiol 2023; 46:126421. [PMID: 37229965 DOI: 10.1016/j.syapm.2023.126421] [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: 02/21/2023] [Revised: 04/07/2023] [Accepted: 04/17/2023] [Indexed: 05/27/2023]
Abstract
The leather-making industry is an age-old industry and desiccation with salt has been one of the most used methodologies for obtaining valuable skins. However, halophiles may proliferate and affect the integrity of the hide-collagen structure, as well as leading to undesirable red colorations or less-frequent purple stains. To understand the basis of these industrial hide contaminations, the microbial community from raw hide samples, salt-cured samples and four different industrial salts, was analyzed by 16S rRNA gene metabarcoding together with standard cultivation methods. Comparison of raw hides and correctly cured hides revealed a core microbiome that was absent from contaminated hides. In addition, archaea were missing from well-cured hides, whereas Psychrobacter and Acinetobacter were highly represented (23 % and 17.4 %, respectively). In damaged hides, only a few operational taxonomic units (OTUs), from among the hundreds detected, were able to proliferate and, remarkably, a single Halomonas OTU represented 57.66 % of the reads. Halobacteria, mainly Halovenus, Halorubrum and Halovivax, increased by up to 36.24-39.5 % in the red- and purple-affected hides. The major contaminants were isolated and hide infections, together with collagenase activity, were evaluated. The results showed that hides enriched with the non-pigmented isolate Halomonas utahensis COIN160 damaged the collagen fibers similarly to Halorubrum, and together they were considered to be one of the major causes. Putative degrading inhibitors were also identified from among the Alkalibacillus isolates. It was concluded that hide contaminations were driven by clonal outbreaks of a few specific microbes, which may have been non-pigmented collagen degraders. Acinetobacter and Alkalibacillus, members of the core microbiome of raw and well-cured salted hides, are suggested as hide contaminant inhibitors that need further analysis.
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Affiliation(s)
| | | | - Juan Tur-Moya
- Hide Consultant, Dpt. Fisiología, Genética y Microbiología, Universidad de Alicante, Spain
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3
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Kokwe L, Nnolim NE, Ezeogu LI, Sithole B, Nwodo UU. Thermoactive metallo-keratinase from Bacillus sp. NFH5: Characterization, structural elucidation, and potential application as detergent additive. Heliyon 2023; 9:e13635. [PMID: 36852054 PMCID: PMC9957710 DOI: 10.1016/j.heliyon.2023.e13635] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Revised: 02/01/2023] [Accepted: 02/06/2023] [Indexed: 02/15/2023] Open
Abstract
In recent times, robust green technological developments have advanced the goal of a circular economy by minimizing waste generation. The study was undertaken to explore the keratinolytic activity of chicken feather-degrading bacteria from South African soil. Isolates coded as SSN-01 and HSN-01 were identified as Bacillus sp. NFH5 and Bacillus sp. FHNM and their sequences were deposited in GenBank, with accession numbers MW165830.1 and MW165831.1, respectively. Extracellular enzyme production and thiol group generation by Bacillus sp. NFH5 peaked at 120 h with 1879.09 ± 88.70 U/mL and 9.49 ± 0.78 mM, respectively. Glutamic acid (4.44%), aspartic acid (3.50%), arginine (3.23%), glycine (2.61%), serine (2.08%), and proline (2.08%) were relatively higher in concentration. Keratinase (KerBAN) activity was highest at pH 8.0 and 90 °C but was inhibited by both EDTA and 1,10-phenanthroline. In addition, the keratinase-encoding gene (kerBAN) accessioned OK033360 had 362 amino acid residues, with molecular weight and theoretical isoelectric point of 39 kDa and 8.81, respectively. Findings from this study highlight the significance of Bacillus sp. NFH5 in the bio-recycling of recalcitrant keratinous wastes to protein hydrolysates - potential dietary supplements for livestock feeds. The properties of KerBAN underscore its application potential in green biotechnological processes.
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Affiliation(s)
- Lupho Kokwe
- SAMRC Microbial Water Quality Monitoring Centre, University of Fort Hare, Alice, Private Bag X1314, 5700, South Africa.,Applied and Environmental Microbiology Research Group (AEMREG), Department of Biochemistry and Microbiology, University of Fort Hare, Alice, 5700, South Africa
| | - Nonso E Nnolim
- SAMRC Microbial Water Quality Monitoring Centre, University of Fort Hare, Alice, Private Bag X1314, 5700, South Africa.,Applied and Environmental Microbiology Research Group (AEMREG), Department of Biochemistry and Microbiology, University of Fort Hare, Alice, 5700, South Africa
| | - Lewis I Ezeogu
- Department of Microbiology, Faculty of Biological Sciences, University of Nigeria, Nsukka, Nigeria
| | - Bruce Sithole
- The Biorefinery Industry Development Facility, Chemicals Cluster, Council for Scientific and Industrial Research, 359 Mazisi Kunene Road, 4001, Glenwood, Durban, South Africa
| | - Uchechukwu U Nwodo
- SAMRC Microbial Water Quality Monitoring Centre, University of Fort Hare, Alice, Private Bag X1314, 5700, South Africa.,Applied and Environmental Microbiology Research Group (AEMREG), Department of Biochemistry and Microbiology, University of Fort Hare, Alice, 5700, South Africa
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Zhang RX, Wu ZW, Cui HY, Chai YN, Hua CW, Wang P, Li L, Yang TY. Production of surfactant-stable keratinase from Bacillus cereus YQ15 and its application as detergent additive. BMC Biotechnol 2022; 22:26. [PMID: 36076195 PMCID: PMC9454225 DOI: 10.1186/s12896-022-00757-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2022] [Accepted: 09/01/2022] [Indexed: 11/26/2022] Open
Abstract
Background With the growing concern for the environment, there are trends that bio-utilization of keratinous waste by keratinases could ease the heavy burden of keratinous waste from the poultry processing and leather industry. Especially surfactant-stable keratinases are beneficial for the detergent industry. Therefore, the production of keratinase by Bacillus cereus YQ15 was improved; the characterization and use of keratinase in detergent were also studied. Results A novel alkaline keratinase-producing bacterium YQ15 was isolated from feather keratin-rich soil and was identified as Bacillus cereus. Based on the improvement of medium components and culture conditions, the maximum keratinase activity (925 U/mL) was obtained after 36 h of cultivation under conditions of 35 °C and 160 rpm. Moreover, it was observed that the optimal reacting temperature and pH of the keratinase are 60 °C and 10.0, respectively; the activity was severely inhibited by PMSF and EDTA. On the contrary, the keratinase showed remarkable stability in the existence of the various surfactants, including SDS, Tween 20, Tween 60, Tween 80, and Triton X-100. Especially, 5% of Tween 20 and Tween 60 increased the activity by 100% and 60%, respectively. Furtherly, the keratinase revealed high efficiency in removing blood stains. Conclusion The excellent compatibility with commercial detergents and the high washing efficiency of removing blood stains suggested its suitability for potential application as a bio-detergent additive. Supplementary Information The online version contains supplementary material available at 10.1186/s12896-022-00757-3.
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Affiliation(s)
- Rong-Xian Zhang
- School of Life Science and Technology, Henan Institute of Science and Technology, Xinxiang, 453003, People's Republic of China.
| | - Zhong-Wei Wu
- School of Life Science and Technology, Henan Institute of Science and Technology, Xinxiang, 453003, People's Republic of China
| | - Hai-Yang Cui
- School of Life Science and Technology, Henan Institute of Science and Technology, Xinxiang, 453003, People's Republic of China
| | - Ying-Nan Chai
- School of Life Science and Technology, Henan Institute of Science and Technology, Xinxiang, 453003, People's Republic of China
| | - Cheng-Wei Hua
- School of Life Science and Technology, Henan Institute of Science and Technology, Xinxiang, 453003, People's Republic of China
| | - Peng Wang
- Blood Transfusion Department, The Third Affiliated Hospital of Xinxiang Medical University, Xinxiang, 453003, People's Republic of China
| | - Lan Li
- School of Life Science and Technology, Henan Institute of Science and Technology, Xinxiang, 453003, People's Republic of China
| | - Tian-You Yang
- School of Life Science and Technology, Henan Institute of Science and Technology, Xinxiang, 453003, People's Republic of China
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Hendrick Q, Nnolim NE, Nontongana N, Nwodo UU. Sphingobacterium multivorum HNFx produced thermotolerant and chemostable keratinase on chicken feathers. Biologia (Bratisl) 2022. [DOI: 10.1007/s11756-022-01126-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Rios P, Bezus B, Cavalitto S, Cavello I. Production and characterization of a new detergent-stable keratinase expressed by Pedobacter sp. 3.14.7, a novel Antarctic psychrotolerant keratin-degrading bacterium. J Genet Eng Biotechnol 2022; 20:81. [PMID: 35612674 PMCID: PMC9133294 DOI: 10.1186/s43141-022-00356-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Accepted: 05/02/2022] [Indexed: 11/10/2022]
Abstract
BACKGROUND Antarctica is one of the harshest environments in the world. Despite this fact, it has been colonized by microorganisms, which had to develop different adaptations in order to survive. By studying their enzymes, we can harness these adaptations in order to use them in various industrial processes. Keratinases (E.C. 3.4.99.11) are characterized by their robustness in withstanding extreme conditions and, along with other enzymes, are commonly added to laundry detergents, which makes their study of industrial interest. RESULTS In this work, a novel keratinase producer, Pedobacter sp. 3.14.7 (MF 347939.1), isolated from Antarctic birds' nests, was identified. This psychrotolerant isolate displays a typical psychrotolerant growth pattern, with an optimal temperature of 20 °C (μmax=0.23 h-1). After 238 h, maximum proteolytic (22.00 ± 1.17 U ml-1) and keratinolytic (33.04 ± 1.09 U ml-1) activities were achieved with a feather sample conversion of approximately 85%. The keratinase present in crude extract was characterized as a metalloprotease with a molecular weight of 25 kDa, stable in a wide range of pH, with an optimum pH of 7.5. Optimum temperature was 55 °C. Wash performance at 20 °C using this crude extract could remove completely blood stain from cotton cloth. CONCLUSION We report a new keratinolytic bacteria from maritime Antarctica. Among its biochemical characteristics, its stability in the presence of different detergents and bleaching agents and its wash performance showed promising results regarding its potential use as a laundry detergent additive.
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Affiliation(s)
- P Rios
- Centro de Investigación y Desarrollo en Fermentaciones Industriales, Facultad de Ciencias Exactas (CINDEFI, CCT La Plata-CONICET, UNLP), Universidad Nacional de la Plata, Calle 47 y 115, (B1900ASH), 1900, La Plata, Argentina
| | - B Bezus
- Centro de Investigación y Desarrollo en Fermentaciones Industriales, Facultad de Ciencias Exactas (CINDEFI, CCT La Plata-CONICET, UNLP), Universidad Nacional de la Plata, Calle 47 y 115, (B1900ASH), 1900, La Plata, Argentina
| | - S Cavalitto
- Centro de Investigación y Desarrollo en Fermentaciones Industriales, Facultad de Ciencias Exactas (CINDEFI, CCT La Plata-CONICET, UNLP), Universidad Nacional de la Plata, Calle 47 y 115, (B1900ASH), 1900, La Plata, Argentina
| | - I Cavello
- Centro de Investigación y Desarrollo en Fermentaciones Industriales, Facultad de Ciencias Exactas (CINDEFI, CCT La Plata-CONICET, UNLP), Universidad Nacional de la Plata, Calle 47 y 115, (B1900ASH), 1900, La Plata, Argentina.
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Zhang J, Su C, Kong XL, Gong JS, Liu YL, Li H, Qin J, Xu ZH, Shi JS. Directed evolution driving the generation of an efficient keratinase variant to facilitate the feather degradation. BIORESOUR BIOPROCESS 2022; 9:38. [PMID: 38647843 PMCID: PMC10992214 DOI: 10.1186/s40643-022-00524-4] [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: 01/23/2022] [Accepted: 03/12/2022] [Indexed: 11/10/2022] Open
Abstract
Keratinases can specifically degrade keratins, which widely exist in hair, horns, claws and human skin. There is a great interest in developing keratinase to manage keratin waste generated by the poultry industry and reusing keratin products in agriculture, medical treatment and feed industries. Degradation of keratin waste by keratinase is more environmentally friendly and more sustainable compared with chemical and physical methods. However, the wild-type keratinase-producing strains usually cannot meet the requirements of industrial production, and some are pathogenic, limiting their development and utilization. The main purpose of this study is to improve the catalytic performance of keratinase via directed evolution technology for the degradation of feathers. We first constructed a mutant library through error-prone PCR and screened variants with enhanced enzyme activity. The keratinase activity was further improved through fermentation conditions optimization and fed-batch strategies in a 7-L bioreactor. As a result, nine mutants with enhanced activity were identified and the highest enzyme activity was improved from 1150 to 8448 U/mL finally. The mutant achieved efficient biodegradation of feathers, increasing the degradation rate from 49 to 88%. Moreover, a large number of amino acids and soluble peptides were obtained as degradation products, which were excellent protein resources to feed. Therefore, the study provided a keratinase mutant with application potential in the management of feather waste and preparation of protein feed additive.
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Affiliation(s)
- Jing Zhang
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Life Sciences and Health Engineering, Jiangnan University, Lihu Avenue No. 1800, Wuxi, 214122, People's Republic of China
- National Engineering Research Center for Cereal Fermentation and Food Biomanufacturing, School of Biotechnology, Jiangnan University, Wuxi, 214122, People's Republic of China
- Jiangsu Provincial Engineering Research Center for Bioactive Product Processing, Jiangnan University, Wuxi, 214122, People's Republic of China
| | - Chang Su
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Life Sciences and Health Engineering, Jiangnan University, Lihu Avenue No. 1800, Wuxi, 214122, People's Republic of China
| | - Xiao-Li Kong
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Life Sciences and Health Engineering, Jiangnan University, Lihu Avenue No. 1800, Wuxi, 214122, People's Republic of China
| | - Jin-Song Gong
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Life Sciences and Health Engineering, Jiangnan University, Lihu Avenue No. 1800, Wuxi, 214122, People's Republic of China.
| | - Yan-Lin Liu
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Life Sciences and Health Engineering, Jiangnan University, Lihu Avenue No. 1800, Wuxi, 214122, People's Republic of China
| | - Heng Li
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Life Sciences and Health Engineering, Jiangnan University, Lihu Avenue No. 1800, Wuxi, 214122, People's Republic of China
| | - Jiufu Qin
- Science Center for Future Foods, Jiangnan University, Wuxi, 214122, People's Republic of China
| | - Zheng-Hong Xu
- National Engineering Research Center for Cereal Fermentation and Food Biomanufacturing, School of Biotechnology, Jiangnan University, Wuxi, 214122, People's Republic of China
- Jiangsu Provincial Engineering Research Center for Bioactive Product Processing, Jiangnan University, Wuxi, 214122, People's Republic of China
| | - Jin-Song Shi
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Life Sciences and Health Engineering, Jiangnan University, Lihu Avenue No. 1800, Wuxi, 214122, People's Republic of China.
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Wang H, Cai C, Gan L, Tian Y. New application of SptA protease: A cleaner and potential water-conserving approach to dehairing of skin. BIOCATAL BIOTRANSFOR 2021. [DOI: 10.1080/10242422.2021.2003788] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
- Hongbin Wang
- College of Biomass Science and Engineering, Sichuan University, Chengdu, PR China
- Key Laboratory of Leather Chemistry and Engineering (Sichuan University), Ministry of Education, Chengdu, PR China
| | - Chufan Cai
- College of Biomass Science and Engineering, Sichuan University, Chengdu, PR China
- Key Laboratory of Leather Chemistry and Engineering (Sichuan University), Ministry of Education, Chengdu, PR China
| | - Longzhan Gan
- College of Biomass Science and Engineering, Sichuan University, Chengdu, PR China
- Key Laboratory of Leather Chemistry and Engineering (Sichuan University), Ministry of Education, Chengdu, PR China
| | - Yongqiang Tian
- College of Biomass Science and Engineering, Sichuan University, Chengdu, PR China
- Key Laboratory of Leather Chemistry and Engineering (Sichuan University), Ministry of Education, Chengdu, PR China
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He F, Chao J, Yang D, Zhang X, Yang C, Xu Z, Jiewei T, Yongqiang T. Optimization of fermentation conditions for production of neutral metalloprotease by Bacillus subtilis SCK6 and its application in goatskin-dehairing. Prep Biochem Biotechnol 2021; 52:789-799. [PMID: 34747342 DOI: 10.1080/10826068.2021.1995413] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
In this study, a high protease-producing strain was screened by spread plate method and identified by molecular biology and morphological identification. It was identified as Bacillus sp. LCB14. A neutral protease gene was cloned and heterologous expressed by B. subtilis SCK6. Then, the recombinant protease was used to dehair the goat skins. The fermentation conditions of neutral protease production by B. subtilis SCK6 were optimized. The single factor experiments, Plackett-Burma experiment, and response surface method were conducted to determine fermentation medium and culture conditions. The optimized medium contained corn meal 49 g/L, soluble starch 28 g/L, soybean meal 17 g/L, corn steep liquor powder 8 g/L, yeast extract 10 g/L, Na2HPO4 2.3 g/L, KH2PO4 1.9 g/L, MgSO4 0.5 g/L, MnCl2 0.1 g/L and ZnSO4 0.05 g/L. The optimized culture conditions were 35 °C and pH 7.0. Under the optimum conditions, the recombinant strain reached 33467.28 U/mL after 72 hr ferment. Moreover, by fed batch in 30 L fermenters, neutral protease production reached 39,440.78 U/mL and shortened fermentation time from 72 hr to 46 hr. Finally, the crude enzyme was utilized to replace sodium sulfide for dehairing of goatskins. The enzymatic dehaired pelts were white, smooth, and soft; the grain side of enzymatic dehaired pelts were clear; there was no obvious damage to the grain side of enzymatic dehaired pelts by visual observation and tactile test. Furthermore, there were no hair roots, hair follicles and other glands in enzymatic dehaired belts, and the collagen fibers of enzymatic dehaired belt were dispersed well by histological analysis.
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Affiliation(s)
- Fuming He
- Chambroad Chemical Industry Research Institute Co., Ltd, Binzhou, China
| | - Jin Chao
- Chambroad Chemical Industry Research Institute Co., Ltd, Binzhou, China
| | - Dandan Yang
- Chambroad Chemical Industry Research Institute Co., Ltd, Binzhou, China
| | - Xinqing Zhang
- Chambroad Chemical Industry Research Institute Co., Ltd, Binzhou, China
| | - Chuanlun Yang
- Chambroad Chemical Industry Research Institute Co., Ltd, Binzhou, China
| | - Zeping Xu
- Chambroad Chemical Industry Research Institute Co., Ltd, Binzhou, China
| | - Tian Jiewei
- Chambroad Chemical Industry Research Institute Co., Ltd, Binzhou, China.,Shan Dong Chambroad Holding Group Co., Ltd, Binzhou, China.,Key Laboratory of Leather Chemistry and Engineering, Ministry of Education and College of Light Industry, Textile and Food Engineering, Sichuan University, Chengdu, China
| | - Tian Yongqiang
- Key Laboratory of Leather Chemistry and Engineering, Ministry of Education and College of Light Industry, Textile and Food Engineering, Sichuan University, Chengdu, China
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Bokveld A, Nnolim NE, Nwodo UU. Chryseobacterium aquifrigidense FANN1 Produced Detergent-Stable Metallokeratinase and Amino Acids Through the Abasement of Chicken Feathers. Front Bioeng Biotechnol 2021; 9:720176. [PMID: 34422784 PMCID: PMC8377754 DOI: 10.3389/fbioe.2021.720176] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Accepted: 07/29/2021] [Indexed: 11/15/2022] Open
Abstract
Microbial keratinases’ versatility in the beneficiation of keratinous waste biomass into high-value products prompts their application in diverse spheres hence, advancing green technology and the bioeconomy. Consequently, a feather-degrading Chryseobacterium aquifrigidense FANN1 (NCBI: MW169027) was used to produce keratinase, and its biochemical properties were determined. The optimization of physicochemical parameters and analysis of the free amino acid constituents of the feather hydrolysate were also carried out. FANN1 showed a maximum keratinase yield of 1,664.55 ± 42.43 U/mL after 72 h, at optimal process conditions that included initial medium pH, incubation temperature, inoculum size, and chicken feather concentration of 8, 30°C, 4% (v/v), and 15 (g/L), respectively. Analysis of degradation product showed 50.32% and 23.25% as the protein value and total free amino acids, respectively, with a relatively high abundance of arginine (2.25%) and serine (2.03%). FANN1 keratinase was optimally active at pH 8.0 and relatively moderate to high temperature (40–50°C). EDTA and 1,10-phenanthroline inhibited the keratinase activity, and that suggests a metallo-keratinase. The enzyme showed remarkable stability in the presence of chemical agents, with residual activity 141 ± 10.38%, 98 ± 0.43%, 111 ± 1.73%, 124 ± 0.87%, 104 ± 3.89%, 107 ± 7.79%, and 112 ± 0.86% against DTT, H2O2, DMSO, acetonitrile, triton X-100, tween-80, and SDS, respectively. The residual activity of FANN1 keratinase was enhanced by Sunlight (129%), Ariel (116%), MAQ (151%), and Surf (143%) compared to the control after 60 min preincubation. Likewise, the enzyme was remarkably stable in the presence Fe3+ (120 ± 5.06%), Ca2+ (100 ± 10.33%), Na+ (122 ± 2.95%), Al3+ (106 ± 10.33%); while Co2+ (68 ± 8.22%) and Fe2+ (51 ± 8.43%) elicited the most repressive effect on keratinase activity. The findings suggest that C. aquifrigidense FANN1 is a potential candidate for keratinous wastes bio-recycling, and the associated keratinase has a good prospect for application in detergent formulation.
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Affiliation(s)
- Amahle Bokveld
- SAMRC Microbial Water Quality Monitoring Centre, University of Fort Hare, Alice, South Africa.,Applied and Environmental Microbiology Research Group (AEMREG), Department of Biochemistry and Microbiology, University of Fort Hare, Alice, South Africa
| | - Nonso E Nnolim
- SAMRC Microbial Water Quality Monitoring Centre, University of Fort Hare, Alice, South Africa.,Applied and Environmental Microbiology Research Group (AEMREG), Department of Biochemistry and Microbiology, University of Fort Hare, Alice, South Africa
| | - Uchechukwu U Nwodo
- SAMRC Microbial Water Quality Monitoring Centre, University of Fort Hare, Alice, South Africa.,Applied and Environmental Microbiology Research Group (AEMREG), Department of Biochemistry and Microbiology, University of Fort Hare, Alice, South Africa
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Recombinant Production and Characterization of an Extracellular Subtilisin-Like Serine Protease from Acinetobacter baumannii of Fermented Food Origin. Protein J 2021; 40:419-435. [PMID: 33870461 PMCID: PMC8053418 DOI: 10.1007/s10930-021-09986-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/05/2021] [Indexed: 12/20/2022]
Abstract
Acinetobacter baumannii is a ubiquitous bacteria that is increasingly becoming a formidable nosocomial pathogen. Due to its clinical relevance, studies on the bacteria's secretory molecules especially extracellular proteases are of interest primarily in relation to the enzyme's role in virulence. Besides, favorable properties that extracellular proteases possess may be exploited for commercial use thus there is a need to investigate extracellular proteases from Acinetobacter baumannii to gain insights into their catalytic properties. In this study, an extracellular subtilisin-like serine protease from Acinetobacter baumannii designated as SPSFQ that was isolated from fermented food was recombinantly expressed and characterized. The mature catalytically active form of SPSFQ shared a high percentage sequence identity of 99% to extracellular proteases from clinical isolates of Acinetobacter baumannii and Klebsiella pneumoniae as well as a moderately high percentage identity to other bacterial proteases with known keratinolytic and collagenolytic activity. The homology model of mature SPSFQ revealed its structure is composed of 10 β-strands, 8 α-helices, and connecting loops resembling a typical architecture of subtilisin-like α/β motif. SPSFQ is catalytically active at an optimum temperature of 40 °C and pH 9. Its activity is stimulated in the presence of Ca2+ and severely inhibited in the presence of PMSF. SPSFQ also displayed the ability to degrade several tissue-associated protein substrates such as keratin, collagen, and fibrin. Accordingly, our study shed light on the catalytic properties of a previously uncharacterized extracellular serine protease from Acinetobacter baumannii that warrants further investigations into its potential role as a virulence factor in pathogenicity and commercial applications.
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Nnolim NE, Nwodo UU. Bacillus sp. CSK2 produced thermostable alkaline keratinase using agro-wastes: keratinolytic enzyme characterization. BMC Biotechnol 2020; 20:65. [PMID: 33317483 PMCID: PMC7734832 DOI: 10.1186/s12896-020-00659-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Accepted: 11/26/2020] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND Chicken feathers are the most abundant agro-wastes emanating from the poultry processing farms and present major concerns to environmentalists. Bioutilization of intractable feather wastes for the production of critical proteolytic enzymes is highly attractive from both ecological and biotechnological perspectives. Consequently, physicochemical conditions influencing keratinase production by Bacillus sp. CSK2 on chicken feathers formulation was optimized, and the keratinase was characterized. RESULTS The highest enzyme activity of 1539.09 ± 68.14 U/mL was obtained after 48 h of incubation with optimized conditions consisting of chicken feathers (7.5 g/L), maltose (2.0 g/L), initial fermentation pH (5.0), incubation temperature (30 °C), and agitation speed (200 rpm). The keratinase showed optimal catalytic efficiency at pH 8.0 and a temperature range of 60 °C - 80 °C. The keratinase thermostability was remarkable with a half-life of above 120 min at 70 °C. Keratinase catalytic efficiency was halted by ethylenediaminetetraacetic acid and 1,10-phenanthroline. However, keratinase activity was enhanced by 2-mercaptoethanol, dimethyl sulfoxide, tween-80, but was strongly inhibited by Al3+ and Fe3+. Upon treatment with laundry detergents, the following keratinase residual activities were achieved: 85.19 ± 1.33% (Sunlight), 90.33 ± 5.95% (Surf), 80.16 ± 2.99% (Omo), 99.49 ± 3.11% (Ariel), and 87.19 ± 0.26% (Maq). CONCLUSION The remarkable stability of the keratinase with an admixture of organic solvents or laundry detergents portends the industrial and biotechnological significance of the biocatalyst.
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Affiliation(s)
- Nonso E Nnolim
- SAMRC Microbial Water Quality Monitoring Centre, University of Fort Hare, Alice, 5700, South Africa.,Applied and Environmental Microbiology Research Group (AEMREG), Department of Biochemistry and Microbiology, University of Fort Hare, Private Bag X1314, Alice, 5700, South Africa
| | - Uchechukwu U Nwodo
- SAMRC Microbial Water Quality Monitoring Centre, University of Fort Hare, Alice, 5700, South Africa. .,Applied and Environmental Microbiology Research Group (AEMREG), Department of Biochemistry and Microbiology, University of Fort Hare, Private Bag X1314, Alice, 5700, South Africa.
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13
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Su C, Gong JS, Qin J, Li H, Li H, Xu ZH, Shi JS. The tale of a versatile enzyme: Molecular insights into keratinase for its industrial dissemination. Biotechnol Adv 2020; 45:107655. [PMID: 33186607 DOI: 10.1016/j.biotechadv.2020.107655] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2020] [Revised: 10/30/2020] [Accepted: 11/02/2020] [Indexed: 01/02/2023]
Abstract
Keratinases are unique among proteolytic enzymes for their ability to degrade recalcitrant insoluble proteins, and they are of critical importance in keratin waste management. Over the past few decades, researchers have focused on discovering keratinase producers, as well as producing and characterizing keratinases. The application potential of keratinases has been investigated in the feed, fertilizer, leathering, detergent, cosmetic, and medical industries. However, the commercial availability of keratinases is still limited due to poor productivity and properties, such as thermostability, storage stability and resistance to organic reagents. Advances in molecular biotechnology have provided powerful tools for enhancing the production and functional properties of keratinase. This critical review systematically summarizes the application potential of keratinase, and in particular certain newly discovered catalytic capabilities. Furthermore, we provide comprehensive insight into mechanistic and molecular aspects of keratinases including analysis of gene sequences and protein structures. In addition, development and current advances in protein engineering of keratinases are summarized and discussed, revealing that the engineering of protein domains such as signal peptides and pro-peptides has become an important strategy to increase production of keratinases. Finally, prospects for further development are also proposed, indicating that advanced protein engineering technologies will lead to improved and additional commercial keratinases for various industrial applications.
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Affiliation(s)
- Chang Su
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Pharmaceutical Sciences, Jiangnan University, Wuxi 214122, PR China
| | - Jin-Song Gong
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Pharmaceutical Sciences, Jiangnan University, Wuxi 214122, PR China.
| | - Jiufu Qin
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark
| | - Heng Li
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Pharmaceutical Sciences, Jiangnan University, Wuxi 214122, PR China
| | - Hui Li
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Pharmaceutical Sciences, Jiangnan University, Wuxi 214122, PR China
| | - Zheng-Hong Xu
- National Engineering Laboratory for Cereal Fermentation Technology, School of Biotechnology, Jiangnan University, Wuxi 214122, PR China; Jiangsu Provincial Research Center for Bioactive Product Processing Technology, Jiangnan University, Wuxi 214122, PR China
| | - Jin-Song Shi
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Pharmaceutical Sciences, Jiangnan University, Wuxi 214122, PR China.
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14
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Sharma I, Kango N. Production and characterization of keratinase by Ochrobactrum intermedium for feather keratin utilization. Int J Biol Macromol 2020; 166:1046-1056. [PMID: 33157140 DOI: 10.1016/j.ijbiomac.2020.10.260] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Accepted: 10/31/2020] [Indexed: 11/29/2022]
Abstract
A newly isolated bacterium producing 55.5 U/mL keratinase on feather meal minimal medium was identified as Ochrobactrum intermedium. Optimization of process parameters by one-variable-at-a-time (OVAT) approach (substrate concentration 0.5% w/v, inoculum size 5% w/v, pH 7.0, 200 rpm for 96 h at 40 °C) resulted in 2.1-fold increase in keratinase secretion (117 U/mL). Keratinase was optimally active at pH 9.0 and 40 °C and was stable at pH 9.0 and 60 °C for 120 min. Calcium ions enhanced keratinase activity (158%) significantly, while it was strongly inhibited by both PMSF and EDTA, indicating it to be a metallo-serine protease. Keratinase degraded native chicken feathers efficiently resulting in 97.9% weight loss along with release of 745.5 μg/mL soluble proteins and 4196.69 μg/mL amino acids. Feather hydrolysate generated by NKIS 1 exhibited significant anti-oxidant and free-radical scavenging activity (90.46%). The present study revealed that O. intermedium NKIS 1 has potential applications in the biodegradation of chicken feathers and the value-addition of poultry waste.
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Affiliation(s)
- Isha Sharma
- Department of Microbiology, Dr. Harisingh Gour Vishwavidyalaya (A Central University), Sagar, M.P. 470003, India
| | - Naveen Kango
- Department of Microbiology, Dr. Harisingh Gour Vishwavidyalaya (A Central University), Sagar, M.P. 470003, India.
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15
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Gonzalo M, Espersen R, Al‐Soud WA, Cristiano Falco F, Hägglund P, Sørensen SJ, Svensson B, Jacquiod S. Azo dying of α-keratin material improves microbial keratinase screening and standardization. Microb Biotechnol 2020; 13:984-996. [PMID: 32110845 PMCID: PMC7264887 DOI: 10.1111/1751-7915.13541] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2019] [Revised: 01/17/2020] [Accepted: 01/17/2020] [Indexed: 11/30/2022] Open
Abstract
Microbial conversion through enzymatic reactions has received a lot of attention as a cost-effective and environmentally friendly way to recover amino acids and short peptides from keratin materials. However, accurate assessment of microbial keratinase activity is not straightforward, and current available methods lack sensitivity and standardization. Here, we suggest an optimized Azokeratin assay, with substrate generated directly from azo-dyed raw keratin material. We introduced supernatant filtration in the protocol for optimal stopping of keratinase reactions instead of the widely used trichloroacetic acid (TCA), as it generated biases and impacted the sensitivity. We furthermore suggest a method for standardization of keratinase activity signals using proteinase K, a well-known keratinase, as a reference enabling reproducibility between studies. Lastly, we evaluated our developed method with several bacterial isolates through benchmarking against a commercial assay (Keratin Azure). Under different setups, the Azokeratin method was more sensitive than commonly used Keratin Azure-based assays (3-fold). We argue that this method could be applied with any type of keratin substrate, enabling more robust and sensitive results which can be used for further comparison with other studies, thus representing an important progress within the field of microbial keratin degradation.
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Affiliation(s)
- Milena Gonzalo
- Section of MicrobiologyUniversity of CopenhagenDK‐2100CopenhagenDenmark
- Present address:
Interactions Arbres/Micro‐organismesINRA/Univ. de LorraineChampenouxFrance
| | - Roall Espersen
- Department of Biotechnology and BiomedicineTechnical University of DenmarkDK‐2800LyngbyDenmark
| | - Waleed A. Al‐Soud
- Section of MicrobiologyUniversity of CopenhagenDK‐2100CopenhagenDenmark
| | - Francesco Cristiano Falco
- Department of Chemical and Biochemical EngineeringTechnical University of DenmarkDK‐2800LyngbyDenmark
| | - Per Hägglund
- Department of Biotechnology and BiomedicineTechnical University of DenmarkDK‐2800LyngbyDenmark
- Present address:
Department of Biomedical SciencesPanum Institute 12.6University of CopenhagenCopenhagenDenmark
| | - Søren J. Sørensen
- Section of MicrobiologyUniversity of CopenhagenDK‐2100CopenhagenDenmark
| | - Birte Svensson
- Department of Biotechnology and BiomedicineTechnical University of DenmarkDK‐2800LyngbyDenmark
| | - Samuel Jacquiod
- Section of MicrobiologyUniversity of CopenhagenDK‐2100CopenhagenDenmark
- Present address:
AgroécologieAgroSup DijonINRAEUniv. BourgogneUniv. Bourgogne Franche‐ComtéF‐21000DijonFrance
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Biochemical characterisation and application of keratinase from Bacillus thuringiensis MT1 to enable valorisation of hair wastes through biosynthesis of vitamin B-complex. Int J Biol Macromol 2020; 153:561-572. [PMID: 32151720 DOI: 10.1016/j.ijbiomac.2020.03.032] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Revised: 03/03/2020] [Accepted: 03/05/2020] [Indexed: 01/22/2023]
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17
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Wang Z, Li X, Tian J, Chu Y, Tian Y. Cloning, heterologous expression and characterization of a novel streptomyces trypsin in Bacillus subtilis SCK6. Int J Biol Macromol 2020; 147:890-897. [PMID: 31739056 DOI: 10.1016/j.ijbiomac.2019.09.248] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2019] [Revised: 08/21/2019] [Accepted: 09/24/2019] [Indexed: 01/10/2023]
Abstract
A novel streptomyces trypsin GM2938 was selected as the object of study. The active GM2938 contains 223 amino acid residues. Constructing recombinant plasmid and transforming Bacillus subtilis SCK6, the heterogenous expression of GM2938 was achieved. Through optimization of fermentation conditions, the expression level of GM2938 reached 1622.2 U/mL (esterase activity) and 33.8 U/mL (amidase activity). The recombinant trypsin was purified and measured: the specific activity of esterase was 5.6 × 103 U/mg, and the specific activity of amidase was 1.1 × 103 U/mg. Furthermore, the enzymatic properties of GM2938 were explore: the optimal reaction temperature and pH were 50 °C and 9.0, respectively; the recombinant enzyme show high stability at 25 °C and range of pH 5.0-9.0; Ca2+, K+, Mg2+, EDTA, DTT, DMSO, methanol, glycerin and ethanediol could promote the esterase and amidase activities at the investigated concentrations, while Fe2+, SDS, tritonx-100, acetone, chloroform and n-hexane inhibited the trypsin activities. Kinetic parameters of GM2938 were calculated: the Km of BAEE was 3.15 × 10-5 mol·L-1, Vmax value was 2.87 × 10-4 mol·L-1·min-1; the Km of BAPAN was 2.20 × 10-4 mol·L-1, the Vmax was 2.40 × 10-4 mol·L-1·min-1. These properties give trypsin GM2938 a potential application prospect.
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Affiliation(s)
- Zhikuan Wang
- Key Laboratory of Leather Chemistry and Engineering, Ministry of Education and College of Biomass Science & Engineering, Sichuan University, Chengdu 610065, PR China
| | - Xiaoguang Li
- Key Laboratory of Leather Chemistry and Engineering, Ministry of Education and College of Biomass Science & Engineering, Sichuan University, Chengdu 610065, PR China
| | - Jiewei Tian
- Key Laboratory of Leather Chemistry and Engineering, Ministry of Education and College of Biomass Science & Engineering, Sichuan University, Chengdu 610065, PR China
| | - Yiwen Chu
- Sichuan Industrial Institute of Antibiotics, Chengdu University, Chengdu 610052, PR China.
| | - Yongqiang Tian
- Key Laboratory of Leather Chemistry and Engineering, Ministry of Education and College of Biomass Science & Engineering, Sichuan University, Chengdu 610065, PR China.
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18
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Yong B, Fei X, Shao H, Xu P, Hu Y, Ni W, Xiao Q, Tao X, He X, Feng H. Recombinant expression and biochemical characterization of a novel keratinase BsKER71 from feather degrading bacterium Bacillus subtilis S1-4. AMB Express 2020; 10:9. [PMID: 31940098 PMCID: PMC6962420 DOI: 10.1186/s13568-019-0939-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2019] [Accepted: 12/20/2019] [Indexed: 01/30/2023] Open
Abstract
Bacillus subtilis S1-4, isolated from chicken feather could efficiently degrade feathers by secreting several extracellular proteases. In order to get insight into the individual protease involved in keratin hydrolysis, a keratinase designed as BsKER71 was cloned and expressed in Bacillus subtilis WB600. In silico analysis revealed that BsKER71 protein contained a mature protein of 36.1 kDa. Further, purified BsKER71 could hydrolyze a variety of natural proteins, such as fibrous protein, collagen protein, casein, keratin and bovine serum albumin. In addition, this keratinase exhibited high enzyme activity in a wide range of pH and optimal pH of 10.0 and 9.0 in the hydrolysis of casein and keratin, respectively. Similarly, the optimal temperature was 55 °C and 50 °C for the hydrolysis of above two substrates, respectively. The hydrolytic activity was significantly inhibited by phenylmethanesulfonyl fluoride (PMSF), indicating the presence of serine residue in the active site. Moreover, ethylenediaminetetraacetic acid (EDTA) and phenanthroline moderately inhibited the hydrolytic activity. The catalytic activity was stimulated by Mg2+ and Ca2+, but greatly inhibited by Cu2+. Furthermore, several chemicals exhibited different effects on the hydrolysis of casein and keratin by BsKER71. These results provided a better understanding of BsKER71 from feather degrading bacterium B. subtilis S1-4.
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A novel unhairing enzyme produced by heterologous expression of keratinase gene (kerT) in Bacillus subtilis. World J Microbiol Biotechnol 2019; 35:122. [DOI: 10.1007/s11274-019-2701-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2019] [Accepted: 07/22/2019] [Indexed: 01/24/2023]
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20
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K. V. A. KERATINOLYTIC ENZYMES: PRODUCERS, PHYSICAL AND CHEMICAL PROPERTIES. APPLICATION FOR BIOTECHNOLOGY. BIOTECHNOLOGIA ACTA 2019. [DOI: 10.15407/biotech12.02.027] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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21
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Su C, Gong JS, Sun YX, Qin J, Zhai S, Li H, Li H, Lu ZM, Xu ZH, Shi JS. Combining Pro-peptide Engineering and Multisite Saturation Mutagenesis To Improve the Catalytic Potential of Keratinase. ACS Synth Biol 2019; 8:425-433. [PMID: 30668109 DOI: 10.1021/acssynbio.8b00442] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Keratinases are becoming biotechnologically important since they have shown potential in hydrolysis of recalcitrant keratins with highly rigid and strongly cross-linked structures. However, the large-scale application of keratinases has been limited by the inefficient expression level and low enzyme activity. In this work, we employed pro-peptide engineering and saturation mutagenesis to construct excellent keratinase variants with improved activities. It turned out that amino acid substitutions at the pro-peptide cleavage site (P1) could accelerate the release of active mature enzymes, resulting in a 3-fold activity increase. Eighteen sites of the pro-peptide area were targeted for codon mutagenesis, and a multisite saturation mutagenesis library of the six potential sites was generated, achieving a significant improvement of keratinase activity from 179 to 1114 units/mL. Also, the mutants exhibited alterant catalytic properties. Finally, fermentation for keratinase production in a 15 L fermenter was carried out, and the enzyme activity reached up to over 3000 units/mL. Our results demonstrated that pro-peptide engineering played a crucial role in high expression and engineering of proteases. This study provides a universal route toward improvement of industrial enzymes that were first synthesized as precursors in the form of pre-pro-protein.
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Affiliation(s)
- Chang Su
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Pharmaceutical Sciences, Jiangnan University, Wuxi 214122, P. R. China
| | - Jin-Song Gong
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Pharmaceutical Sciences, Jiangnan University, Wuxi 214122, P. R. China
| | - Yu-Xin Sun
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Pharmaceutical Sciences, Jiangnan University, Wuxi 214122, P. R. China
| | - Jiufu Qin
- Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, DK-2800 Kongens Lyngby, Denmark
| | - Shen Zhai
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Pharmaceutical Sciences, Jiangnan University, Wuxi 214122, P. R. China
| | - Heng Li
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Pharmaceutical Sciences, Jiangnan University, Wuxi 214122, P. R. China
| | - Hui Li
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Pharmaceutical Sciences, Jiangnan University, Wuxi 214122, P. R. China
| | - Zhen-Ming Lu
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Pharmaceutical Sciences, Jiangnan University, Wuxi 214122, P. R. China
- National Engineering Laboratory for Cereal Fermentation Technology, School of Biotechnology, Jiangnan University, Wuxi 214122, P. R. China
| | - Zheng-Hong Xu
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Pharmaceutical Sciences, Jiangnan University, Wuxi 214122, P. R. China
- National Engineering Laboratory for Cereal Fermentation Technology, School of Biotechnology, Jiangnan University, Wuxi 214122, P. R. China
| | - Jin-Song Shi
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Pharmaceutical Sciences, Jiangnan University, Wuxi 214122, P. R. China
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Adelere IA, Lateef A. Degradation of Keratin Biomass by Different Microorganisms. KERATIN AS A PROTEIN BIOPOLYMER 2019. [DOI: 10.1007/978-3-030-02901-2_5] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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23
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Vidmar B, Vodovnik M. Microbial Keratinases: Enzymes with Promising Biotechnological Applications. Food Technol Biotechnol 2018; 56:312-328. [PMID: 30510475 PMCID: PMC6233012 DOI: 10.17113/ftb.56.03.18.5658] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Keratin is a complex and structurally stable protein found in human and animal hard tissues, such as feathers, wool, hair, hoof and nails. Some of these, like feathers and wool, represent one of the main sources of protein-rich waste with significant potential to be transformed into value-added products such as feed, fertilizers or bioenergy. A major limitation impeding valorization of keratinous substrates is their recalcitrant structure and resistance to hydrolysis by common proteases. However, specialized keratinolytic enzymes produced by some microorganisms can efficiently degrade these substrates. Keratinases have already found a purpose in pharmaceutical, textile and leather industries. However, their wider implementation in other processes, such as cost-effective (pre)treatment of poultry waste, still requires optimization of production and performance of the available enzymes. Here we present a comprehensive review covering molecular properties and characteristics of keratinases, their classification, traditional and novel approaches in discovery of novel enzymes, production, characterization, improvement and biotechnological applications.
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Affiliation(s)
- Beti Vidmar
- Chair of Microbiology and Microbial Biotechnology, Department of Animal Science, Biotechnical Faculty, University of Ljubljana, Groblje 3,
SI-1230 Domžale, Slovenia
| | - Maša Vodovnik
- Chair of Microbiology and Microbial Biotechnology, Department of Animal Science, Biotechnical Faculty, University of Ljubljana, Groblje 3,
SI-1230 Domžale, Slovenia
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Biochemical characterization of a novel surfactant-stable serine keratinase with no collagenase activity from Brevibacillus parabrevis CGMCC 10798. Int J Biol Macromol 2016; 93:843-851. [PMID: 27651275 DOI: 10.1016/j.ijbiomac.2016.09.063] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Revised: 09/14/2016] [Accepted: 09/15/2016] [Indexed: 11/22/2022]
Abstract
Dehairing is a high pollution process in leather industry. Conventionally, the lime-sulfide mediated chemical process for dehairing would lead to the discharge of pollutants and corrosion of industrial equipment. Concerning these problems, keratinase has become a promising candidate for dehairing process in recent years. In this study, a keratinase-producing bacterium was isolated from sheepfold soil and identified as Brevibacillus parabrevis CGMCC 10798 based on the biochemical characteristics and molecular identification. The keratinase was purified to electrophoretic homogeneity with 17.19% of recovery, 13.18 folds of purification and an estimated molecular weight of 28kDa. The enzyme exhibited high keratinase activity and no collagenase activity. Besides, the keratinase showed optimal activity at 60°C and pH 8.0. The enzyme activity could be significantly increased in the presence of Na+ and Ca2+. And it was inhibited by EDTA, and PMSF, which indicated that the keratinase belongs to serine-metallo protease. The enzyme could remain stable in the presence of surfactants. Especially, 5mM Tween 40 and Triton 100 could improve the activity by 11% and 30%, respectively. Moreover, B. parabrevis keratinase could completely dehair goat wool within 7h, which indicated its application potential in leather industry.
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