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Das S, Das A, Das N, Nath T, Langthasa M, Pandey P, Kumar V, Choure K, Kumar S, Pandey P. Harnessing the potential of microbial keratinases for bioconversion of keratin waste. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2024:10.1007/s11356-024-34233-6. [PMID: 38985428 DOI: 10.1007/s11356-024-34233-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2023] [Accepted: 06/30/2024] [Indexed: 07/11/2024]
Abstract
The increasing global consumption of poultry meat has led to the generation of a vast quantity of feather keratin waste daily, posing significant environmental challenges due to improper disposal methods. A growing focus is on utilizing keratinous polymeric waste, amounting to millions of tons annually. Keratins are biochemically rigid, fibrous, recalcitrant, physiologically insoluble, and resistant to most common proteolytic enzymes. Microbial biodegradation of feather keratin provides a viable solution for augmenting feather waste's nutritional value while mitigating environmental contamination. This approach offers an alternative to traditional physical and chemical treatments. This review focuses on the recent findings and work trends in the field of keratin degradation by microorganisms (bacteria, actinomycetes, and fungi) via keratinolytic and proteolytic enzymes, as well as the limitations and challenges encountered due to the low thermal stability of keratinase, and degradation in the complex environmental conditions. Therefore, recent biotechnological interventions such as designing novel keratinase with high keratinolytic activity, thermostability, and binding affinity have been elaborated here. Enhancing protein structural rigidity through critical engineering approaches, such as rational design, has shown promise in improving the thermal stability of proteins. Concurrently, metagenomic annotation offers insights into the genetic foundations of keratin breakdown, primarily predicting metabolic potential and identifying probable keratinases. This may extend the understanding of microbial keratinolytic mechanisms in a complex community, recognizing the significance of synergistic interactions, which could be further utilized in optimizing industrial keratin degradation processes.
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Affiliation(s)
- Sandeep Das
- Department of Microbiology, Assam University, Silchar, 788011, Assam, India
| | - Ankita Das
- Department of Microbiology, Assam University, Silchar, 788011, Assam, India
| | - Nandita Das
- Department of Microbiology, Assam University, Silchar, 788011, Assam, India
| | - Tamanna Nath
- Department of Microbiology, Assam University, Silchar, 788011, Assam, India
| | | | - Prisha Pandey
- Department of Biotechnology, Royal Global University, Guwahati, 781035, Assam, India
| | - Vijay Kumar
- Himalayan School of Biosciences, Swami Rama Himalayan University, Dehradun, India, 248016
| | - Kamlesh Choure
- Department of Biotechnology, AKS University, Satna, 485001, Madhya Pradesh, India
| | - Sanjeev Kumar
- Department of Life Sciences and Bioinformatics, Assam University, Silchar, 788011, Assam, India
| | - Piyush Pandey
- Department of Microbiology, Assam University, Silchar, 788011, Assam, India.
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Khan A, Mehmood K, Nadhman A, Khan SU, Shah AA, Shah Z. Microbial production of keratinase from Bacillus velezensis strain MAMA: A novel enzyme for eco-friendly degradation of keratin waste. Heliyon 2024; 10:e32338. [PMID: 38988557 PMCID: PMC11233875 DOI: 10.1016/j.heliyon.2024.e32338] [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: 08/24/2023] [Revised: 05/31/2024] [Accepted: 06/02/2024] [Indexed: 07/12/2024] Open
Abstract
Keratin waste has become an increasingly serious environmental and health hazard. Keratin waste is mainly composed of keratin protein, which is one of the most difficult polymers to break down in nature and is resistant to many physical, chemical, and biological agents. With physical and chemical methods being environment damaging and costly, microbial degradation of keratin using keratinase enzyme is of great significance as it is both environment friendly and cost-effective. The aim of this study was to extract and purify keratinase from bacterial species isolated from the soil. Among the organisms, an isolate of Bacillus velezensis, coded as MAMA could break down chicken feathers within 72 hours (h). The isolated strain produced significant levels of keratinase in mineral salt medium by supplying chicken feathers as the sole source of nitrogen and carbon. Feather deterioration was observed with the naked eye, and enzyme activity was evaluated using a spectrophotometric assay. Sodium dodecyl-sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and zymography results revealed that the keratinase protein produced by Bacillus velezensis had a molecular weight between 40 and 55 kilodalton (kDa).
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Affiliation(s)
- Aimon Khan
- Institute of Integrative Biosciences, CECOS University Peshawar, Pakistan
| | - Kashif Mehmood
- Institute of Integrative Biosciences, CECOS University Peshawar, Pakistan
| | - Akhtar Nadhman
- Institute of Integrative Biosciences, CECOS University Peshawar, Pakistan
| | - Sami Ullah Khan
- Department of Microbiology, Quaid-i-Azam University, Islamabad, Pakistan
| | - Aamer Ali Shah
- Department of Microbiology, Quaid-i-Azam University, Islamabad, Pakistan
| | - Ziaullah Shah
- Department of Pharmacy, CECOS University Peshawar, Pakistan
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Ablimit N, Zheng F, Wang Y, Wen J, Wang H, Deng K, Cao Y, Wang Z, Jiang W. Bacillus velezensis strain NA16 shows high poultry feather-degrading efficiency, protease and amino acid production. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2024; 278:116353. [PMID: 38691885 DOI: 10.1016/j.ecoenv.2024.116353] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Revised: 04/12/2024] [Accepted: 04/18/2024] [Indexed: 05/03/2024]
Abstract
Isolated Bacillus velezensis strain NA16, which produces proteases, amino acids and the transcription levels of different keratinolytic enzymes and disulfide reductase genes in whole gene sequencing, was evaluated during feather degradation. The result shows under optimum fermentation conditions, chicken feather fermentation showed total amino acid concentration of 7599 mg/L, degradation efficiency of 99.3% at 72 h, and protease activity of 1058 U/mL and keratinase activity of 288 U/mL at 48 h. Goose feather fermentation showed total amino acid concentration of 4918 mg/L (96 h), and degradation efficiency was 98.9% at 120 h. Chicken feather fermentation broth at 72 h showed high levels of 17 amino acids, particularly phenylalanine (1050 ± 1.90 mg/L), valine (960 ± 1.04 mg/L), and glutamic (950 ± 3.00 mg/L). Scanning electron microscopy and Fourier transform infrared analysis revealed the essential role of peptide bond cleavage in structural changes and degradation of feathers. Protein purification and zymographic analyses revealed a key role in feather degradation of the 39-kDa protein encoded by gene1031, identified as an S8 family serine peptidase. Whole genome sequencing of NA16 revealed 26 metalloproteinase genes and 22 serine protease genes. Among the proteins, S8 family serine peptidase (gene1031, gene1428) and S9 family peptidase (gene3132) were shown by transcription analysis to play major roles in chicken feather degradation. These findings revealed the transcription levels of different families of keratinolytic enzymes in the degradation of feather keratin by microorganisms, and suggested potential applications of NA16 in feather waste management and amino acid production.
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Affiliation(s)
- Nuraliya Ablimit
- State Key Laboratory of Animal Biotech Breeding, College of Biological Sciences, China Agricultural University, Beijing 100193, China.
| | - Fengzhen Zheng
- College of Biological and Environmental Engineering, Zhejiang Shuren University, 36 Zhoushan E Rd, Hangzhou 310015, China.
| | - Yan Wang
- State Key Laboratory of Animal Biotech Breeding, College of Biological Sciences, China Agricultural University, Beijing 100193, China.
| | - Jiaqi Wen
- State Key Laboratory of Animal Biotech Breeding, College of Biological Sciences, China Agricultural University, Beijing 100193, China.
| | - Hui Wang
- State Key Laboratory of Animal Biotech Breeding, College of Biological Sciences, China Agricultural University, Beijing 100193, China.
| | - Kun Deng
- State Key Laboratory of Animal Biotech Breeding, College of Biological Sciences, China Agricultural University, Beijing 100193, China.
| | - Yunhe Cao
- State Key Laboratory of Animal Nutrition, China Agricultural University, Beijing 100193, China.
| | - Zengli Wang
- College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100193, China.
| | - Wei Jiang
- State Key Laboratory of Animal Biotech Breeding, College of Biological Sciences, China Agricultural University, Beijing 100193, China.
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Saeed M, Yan M, Ni Z, Hussain N, Chen H. Molecular strategies to enhance the keratinase gene expression and its potential implications in poultry feed industry. Poult Sci 2024; 103:103606. [PMID: 38479096 PMCID: PMC10951097 DOI: 10.1016/j.psj.2024.103606] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2024] [Revised: 02/18/2024] [Accepted: 02/27/2024] [Indexed: 03/24/2024] Open
Abstract
The tons of keratin waste are produced by the poultry and meat industry which is an insoluble and protein-rich material found in hair, feathers, wool, and some epidermal wastes. These waste products could be degraded and recycled to recover protein, which can save our environment. One of the potential strategy to achieve this target is use of microbial biotreatment which is more convenient, cost-effective, and environment-friendly by formulating hydrolysate complexes that could be administered as protein supplements, bioactive peptides, or animal feed ingredients. Keratin degradation shows great promise for long-term protein and amino acid recycling. According to the MEROPS database, known keratinolytic enzymes currently belong to at least 14 different protease families, including S1, S8, S9, S10, S16, M3, M4, M14, M16, M28, M32, M36, M38, and M55. In addition to exogenous attack (proteases from families S9, S10, M14, M28, M38, and M55), the various keratinolytic enzymes also function via endo-attack (proteases from families S1, S8, S16, M4, M16, and M36). Biotechnological methods have shown great promise for enhancing keratinase expression in different strains of microbes and different protein engineering techniques in genetically modified microbes such as bacteria and some fungi to enhance keratinase production and activity. Some microbes produce specific keratinolytic enzymes that can effectively degrade keratin substrates. Keratinases have been successfully used in the leather, textile, and pharmaceutical industries. However, the production and efficiency of existing enzymes need to be optimized before they can be used more widely in other processes, such as the cost-effective pretreatment of chicken waste. These can be improved more effectively by using various biotechnological applications which could serve as the best and novel approach for recycling and degrading biomass. This paper provides practical insights about molecular strategies to enhance keratinase expression to effectively utilize various poultry wastes like feathers and feed ingredients like soybean pulp. Furthermore, it describes the future implications of engineered keratinases for environment friendly utilization of wastes and crop byproducts for their better use in the poultry feed industry.
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Affiliation(s)
- Muhammad Saeed
- School of Life Sciences, Jiangsu University, Zhenjiang, 212013, China
| | - Mingchen Yan
- School of Life Sciences, Jiangsu University, Zhenjiang, 212013, China
| | - Zhong Ni
- School of Life Sciences, Jiangsu University, Zhenjiang, 212013, China
| | - Nazar Hussain
- School of Life Sciences, Jiangsu University, Zhenjiang, 212013, China
| | - Huayou Chen
- School of Life Sciences, Jiangsu University, Zhenjiang, 212013, China.
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Song C, Liu R, Yin D, Xie C, Liang Y, Yang D, Jiang M, Zhang H, Shen N. A Comparative Transcriptome Analysis Unveils the Mechanisms of Response in Feather Degradation by Pseudomonas aeruginosa Gxun-7. Microorganisms 2024; 12:841. [PMID: 38674785 PMCID: PMC11052024 DOI: 10.3390/microorganisms12040841] [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: 03/06/2024] [Revised: 04/15/2024] [Accepted: 04/17/2024] [Indexed: 04/28/2024] Open
Abstract
Microbial degradation of feathers offers potential for bioremediation, yet the microbial response mechanisms warrant additional investigation. In prior work, Pseudomonas aeruginosa Gxun-7, which demonstrated robust degradation of feathers at elevated concentrations, was isolated. However, the molecular mechanism of this degradation remains only partially understood. To investigate this, we used RNA sequencing (RNA-seq) to examine the genes that were expressed differentially in P. aeruginosa Gxun-7 when exposed to 25 g/L of feather substrate. The RNA-seq analysis identified 5571 differentially expressed genes; of these, 795 were upregulated and 603 were downregulated. Upregulated genes primarily participated in proteolysis, amino acid, and pyruvate metabolism. Genes encoding proteases, as well as those involved in sulfur metabolism, phenazine synthesis, and type VI secretion systems, were notably elevated, highlighting their crucial function in feather decomposition. Integration of Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) taxonomies, combined with a review of the literature, led us to propose that metabolic feather degradation involves environmental activation, reducing agent secretion, protease release, peptide/amino acid uptake, and metabolic processes. Sulfite has emerged as a critical activator of keratinase catalysis, while cysteine serves as a regulatory mediator. qRT-PCR assay results for 11 selected gene subset corroborated the RNA-seq findings. This study enhances our understanding of the transcriptomic responses of P. aeruginosa Gxun-7 to feather degradation and offers insights into potential degradation mechanisms, thereby aiding in the formulation of effective feather waste management strategies in poultry farming.
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Affiliation(s)
- Chaodong Song
- Guangxi Key Laboratory of Polysaccharide Materials and Modification, School of Marine Sciences and Biotechnology, Guangxi Minzu University, Nanning 530000, China; (C.S.); (R.L.); (D.Y.); (C.X.); (Y.L.); (M.J.)
| | - Rui Liu
- Guangxi Key Laboratory of Polysaccharide Materials and Modification, School of Marine Sciences and Biotechnology, Guangxi Minzu University, Nanning 530000, China; (C.S.); (R.L.); (D.Y.); (C.X.); (Y.L.); (M.J.)
| | - Doudou Yin
- Guangxi Key Laboratory of Polysaccharide Materials and Modification, School of Marine Sciences and Biotechnology, Guangxi Minzu University, Nanning 530000, China; (C.S.); (R.L.); (D.Y.); (C.X.); (Y.L.); (M.J.)
| | - Chenjie Xie
- Guangxi Key Laboratory of Polysaccharide Materials and Modification, School of Marine Sciences and Biotechnology, Guangxi Minzu University, Nanning 530000, China; (C.S.); (R.L.); (D.Y.); (C.X.); (Y.L.); (M.J.)
| | - Ying Liang
- Guangxi Key Laboratory of Polysaccharide Materials and Modification, School of Marine Sciences and Biotechnology, Guangxi Minzu University, Nanning 530000, China; (C.S.); (R.L.); (D.Y.); (C.X.); (Y.L.); (M.J.)
| | - Dengfeng Yang
- Guangxi Key Laboratory of Marine Natural Products and Combinatorial Biosynthesis Chemistry, Guangxi Beibu Gulf Marine Research Center, Guangxi Academy of Sciences, No. 98, Daxue Road, Nanning 530007, China;
| | - Mingguo Jiang
- Guangxi Key Laboratory of Polysaccharide Materials and Modification, School of Marine Sciences and Biotechnology, Guangxi Minzu University, Nanning 530000, China; (C.S.); (R.L.); (D.Y.); (C.X.); (Y.L.); (M.J.)
| | - Hongyan Zhang
- Guangxi Key Laboratory of Polysaccharide Materials and Modification, School of Marine Sciences and Biotechnology, Guangxi Minzu University, Nanning 530000, China; (C.S.); (R.L.); (D.Y.); (C.X.); (Y.L.); (M.J.)
| | - Naikun Shen
- Guangxi Key Laboratory of Polysaccharide Materials and Modification, School of Marine Sciences and Biotechnology, Guangxi Minzu University, Nanning 530000, China; (C.S.); (R.L.); (D.Y.); (C.X.); (Y.L.); (M.J.)
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Park G, Lee KM, Lee YS, Kim Y, Jeon CM, Lee OM, Kim YJ, Son HJ. Biodegradation and valorization of feather waste using the keratinase-producing bacteria and their application in environmentally hazardous industrial processes. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 346:118986. [PMID: 37714086 DOI: 10.1016/j.jenvman.2023.118986] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2023] [Revised: 08/21/2023] [Accepted: 09/09/2023] [Indexed: 09/17/2023]
Abstract
Poultry feathers are widely discarded as waste worldwide and are considered an environmental pollutant and a reservoir of pathogenic bacteria. Therefore, developing sustainable and environmentally friendly methods for managing feather waste is one of the important environmental protection requirements. In this study, we investigated a rapid and eco-friendly method for the degradation and valorization of feather waste using keratinase-producing Pseudomonas geniculata H10, and evaluated the applicability of keratinase in environmentally hazardous chemical processes. Strain H10 completely degraded chicken feathers within 48 h by producing keratinase using them as sources of carbon, nitrogen, and sulfur. The culture contained a total of 402.8 μM amino acids, including 8 essential amino acids, which was higher than the chemical treatment. Keratinase was a serine-type metalloprotease with optimal temperature and pH of 30 °C and 9, respectively, and showed relatively high stability at 10-40 °C and pH 3-10. Keratinase was also able to degrade various insoluble keratins such as duck feathers, wool, human hair, and nails. Furthermore, keratinase exhibited more efficient depilation and wool modification than chemical treatment, as well as novel functionalities such as nematicidal and exfoliating activities. This suggests that strain H10 is a promising candidate for the efficient degradation and valorization of feather waste, as well as the improvement of current industrial processes that use hazardous chemicals.
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Affiliation(s)
- Gyulim Park
- Department of Life Science and Environmental Biochemistry/Life and Industry Convergence Research Institute, Pusan National University, Miryang, 50463, Republic of Korea
| | - Kwang Min Lee
- Department of Life Science and Environmental Biochemistry/Life and Industry Convergence Research Institute, Pusan National University, Miryang, 50463, Republic of Korea
| | - Young Seok Lee
- Department of Life Science and Environmental Biochemistry/Life and Industry Convergence Research Institute, Pusan National University, Miryang, 50463, Republic of Korea
| | - Yedam Kim
- Department of Life Science and Environmental Biochemistry/Life and Industry Convergence Research Institute, Pusan National University, Miryang, 50463, Republic of Korea
| | - Chae Min Jeon
- Department of Life Science and Environmental Biochemistry/Life and Industry Convergence Research Institute, Pusan National University, Miryang, 50463, Republic of Korea
| | - O-Mi Lee
- Avian Disease Division, Animal and Plant Quarantine Agency, Gimcheon, 39660, Republic of Korea
| | - Yu-Jin Kim
- Department of Life Science and Environmental Biochemistry/Life and Industry Convergence Research Institute, Pusan National University, Miryang, 50463, Republic of Korea
| | - Hong-Joo Son
- Department of Life Science and Environmental Biochemistry/Life and Industry Convergence Research Institute, Pusan National University, Miryang, 50463, Republic of Korea.
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de Menezes CLA, Boscolo M, da Silva R, Gomes E, da Silva RR. The degradation of chicken feathers by Ochrobactrum intermedium results in antioxidant and metal chelating hydrolysates and proteolytic enzymes for staphylococcal biofilm dispersion. 3 Biotech 2023; 13:202. [PMID: 37220603 PMCID: PMC10199982 DOI: 10.1007/s13205-023-03619-7] [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: 11/18/2022] [Accepted: 05/06/2023] [Indexed: 05/25/2023] Open
Abstract
The increase in the generation of chicken feathers, due to the large production of the poultry industry, has created the need to search for ecologically safer ways to manage these residues. As a sustainable alternative for recycling keratin waste, we investigated the ability of the bacterium Ochrobactrum intermedium to hydrolyze chicken feathers and the valorization of the resulting enzymes and protein hydrolysate. In submerged fermentation with three different inoculum sizes (2.5, 5.0, and 10.0 mg of bacterial cells per 50 mL of medium), the fastest degradation of feathers was achieved with 5.0 mg cells, in which a complete decomposition of the substrate (96 h) and earlier peaks of keratinolytic and caseinolytic activities were detected. In the resulting protein hydrolysate, we noticed antioxidant and Fe2+ and Cu2+ chelating activities. ABTS scavenging, Fe3+-reducing ability and metal chelating activities of the fermentative samples followed the same trend of feather degradation; as feather mass decreased in the media, these activities increased. Furthermore, we noticed about 47% and 60% dispersion of established 7-day biofilms formed by S. aureus after enzymatic treatment for 5 h and 24 h, respectively. These findings highlight the potential use of this bacterium as an environmentally friendly alternative to treat this poultry waste and offer valuable products.
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Affiliation(s)
- Cíntia Lionela Ambrosio de Menezes
- Instituto de Biociências, Letras e Ciências Exatas, Universidade Estadual Paulista “Júlio de Mesquita Filho”, R/ Cristóvão Colombo, 2265. Jd Nazareth, Ibilce-Unesp, São José do Rio Preto, São Paulo Brazil
| | - Maurício Boscolo
- Instituto de Biociências, Letras e Ciências Exatas, Universidade Estadual Paulista “Júlio de Mesquita Filho”, R/ Cristóvão Colombo, 2265. Jd Nazareth, Ibilce-Unesp, São José do Rio Preto, São Paulo Brazil
| | - Roberto da Silva
- Instituto de Biociências, Letras e Ciências Exatas, Universidade Estadual Paulista “Júlio de Mesquita Filho”, R/ Cristóvão Colombo, 2265. Jd Nazareth, Ibilce-Unesp, São José do Rio Preto, São Paulo Brazil
| | - Eleni Gomes
- Instituto de Biociências, Letras e Ciências Exatas, Universidade Estadual Paulista “Júlio de Mesquita Filho”, R/ Cristóvão Colombo, 2265. Jd Nazareth, Ibilce-Unesp, São José do Rio Preto, São Paulo Brazil
| | - Ronivaldo Rodrigues da Silva
- Instituto de Biociências, Letras e Ciências Exatas, Universidade Estadual Paulista “Júlio de Mesquita Filho”, R/ Cristóvão Colombo, 2265. Jd Nazareth, Ibilce-Unesp, São José do Rio Preto, São Paulo Brazil
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Lai Y, Wu X, Zheng X, Li W, Wang L. Insights into the keratin efficient degradation mechanism mediated by Bacillus sp. CN2 based on integrating functional degradomics. BIOTECHNOLOGY FOR BIOFUELS AND BIOPRODUCTS 2023; 16:59. [PMID: 37016453 PMCID: PMC10071666 DOI: 10.1186/s13068-023-02308-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Accepted: 03/24/2023] [Indexed: 04/06/2023]
Abstract
BACKGROUND Keratin, the main component of chicken feather, is the third most abundant material after cellulose and chitin. Keratin can be converted into high-value compounds and is considered a potential high-quality protein supplement; However, its recalcitrance makes its breakdown a challenge, and the mechanisms of action of keratinolytic proteases-mediated keratinous substrates degradation are not yet fully elucidated. Bacillus sp. CN2, having many protease-coding genes, is a dominant species in keratin-rich materials environments. To explore the degradation patterns of feather keratin, in this study, we investigated the characteristics of feather degradation by strain CN2 based on the functional-degradomics technology. RESULTS Bacillus sp. CN2 showed strong feather keratin degradation activities, which could degrade native feathers efficiently resulting in 86.70% weight loss in 24 h, along with the production of 195.05 ± 6.65 U/mL keratinases at 48 h, and the release of 0.40 mg/mL soluble proteins at 60 h. The extracellular protease consortium had wide substrate specificity and exhibited excellent biodegradability toward soluble and insoluble proteins. Importantly, analysis of the extracellular proteome revealed the presence of a highly-efficient keratin degradation system. Firstly, T3 γ-glutamyltransferase provides a reductive force to break the dense disulfide bond structure of keratin. Then S8B serine endopeptidases first hydrolyze keratin to expose more cleavage sites. Finally, keratin is degraded into small peptides under the synergistic action of proteases such as M4, S8C, and S8A. Consistent with this, high-performance liquid chromatography (HPLC) and amino acid analysis showed that the feather keratin hydrolysate contained a large number of soluble peptides and essential amino acids. CONCLUSIONS The specific expression of γ-glutamyltransferase and co-secretion of endopeptidase and exopeptidase by the Bacillus sp. CN2 play an important role in feather keratin degradation. This insight increases our understanding of the keratinous substrate degradation and may inspire the design of the optimal enzyme cocktails for more efficient exploration of protein resources in industrial applications.
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Affiliation(s)
- Yuhong Lai
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, 72 Binhai Road, Qingdao, 266237, Shandong, China
| | - Xiuyun Wu
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, 72 Binhai Road, Qingdao, 266237, Shandong, China
| | | | - Weiguang Li
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, 72 Binhai Road, Qingdao, 266237, Shandong, China
| | - Lushan Wang
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, 72 Binhai Road, Qingdao, 266237, Shandong, China.
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Kanagaraj J, Panda RC, Prasanna R, Tamilselvi A. An efficient dehairing system supported by oxidative-enzymatic auxiliary towards sustainability. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:43817-43832. [PMID: 36662437 DOI: 10.1007/s11356-023-25380-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Accepted: 01/13/2023] [Indexed: 06/17/2023]
Abstract
A method of dehairing of goat skins using oxidative chemicals and protease enzymes has been attempted. The dehairing process is one of the important and essential steps in leather making, where hair is removed by lime and sodium sulphide in the conventional process. This conventional dehairing system generates a higher amount of pollution problem as compared to the other unit operations and unit processes. In this work, dehairing of the goat skins through oxidative agents namely magnesium peroxide and protease enzyme has been attempted. For this, protease has been produced from Bacillus sp. at the laboratory level and the activity was found. The dehairing of goat skins takes place for the duration of 14-16 h. The leather produced with the experimental sample showed comparable organoleptic and strength properties with the conventional sample. This method paved the way for the reduction of pollution loads especially BOD, COD, and TDS to the level of 59, 27, and 77%, respectively, in comparison with the control sample. The reaction kinetics for the formation of the ligand-macromolecular complex is found in the isothermal titration calorimetry (ITC) experiment and a mathematical model has been formulated. The dyed crust leather showed comparable colour properties. In addition to that, there is a reduction in processing time for leather making through skipping reliming and deliming processes which are said to be another advantage of this method. The physical strength properties of the experimental leather were also comparable with conventionally produced leather.
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Affiliation(s)
- James Kanagaraj
- Department of Leather Processing Technology, CSIR-Central Leather Research Institute, Adyar, Chennai, 20, India.
| | - Rames Chandra Panda
- Department of Chemical Engineering, CSIR-CLRI, Adyar, Chennai, 600020, India
| | - Ramakrishna Prasanna
- Department of Leather Processing Technology, CSIR-Central Leather Research Institute, Adyar, Chennai, 20, India
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Dume B, Hanc A, Svehla P, Michal P, Solcova O, Chane AD, Nigussie A. Nutrient recovery and changes in enzyme activity during vermicomposting of hydrolysed chicken feather residue. ENVIRONMENTAL TECHNOLOGY 2022:1-15. [PMID: 36368925 DOI: 10.1080/09593330.2022.2147451] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Accepted: 11/05/2022] [Indexed: 06/16/2023]
Abstract
Chicken feathers are hazardous to the environment because of their poor digestibility and potential as a source of environmental contaminants. However, this waste contains valuable plant nutrients that can be recovered and used to improve soil fertility and agricultural productivity. The objectives of this study were to evaluate how effective vermicomposting is at recovering nutrients and changes in enzymatic activity during vermicomposting of hydrolysed chicken feather residues (HCFR). The study included four treatments with three replications at different HCFR and pelletized wheat straw (PWS) mixing proportions: (T1) 25% HCFR+75% PWS with earthworms, (T2) 25% HCFR+75% PWS without earthworms, (T3) 50% HCFR+50% PWS with earthworms, and (T4) 50% HCFR+50% PWS (w/w) without earthworms. Eisenia andrei was used in the experiment for 120 days. Earthworm treatments recovered more available plant nutrients than non-earthworm treatments by 14% N - NO 3 - (T1); 50% K (T3); 47% Mg (T3); 75% P (T3); 55% B (T3); 34% Cu (T3); 40% Fe (T1); 46% Mn (T3); 11% Zn (T1). However, N - NH 4 + was significantly reduced by -80% (T1). Acid phosphatase, arylsulphatase, alanine aminopeptidase, and leucine aminopeptidase were more active in the treatments with earthworms and positively correlated with P and C: N ratio. Alanine aminopeptidase (3752 µmol AMCA.g-1.h-1) and leucine aminopeptidase (4252 µmol AMCL.g-1.h-1) had higher activities in T3 on day 60 of vermicomposting. As a result, the earthworm treatment recovers more plant nutrients than the non-earthworm treatments, and it can be recommended as a better vermicomposting approach for nutrient recovery from HCFR.
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Affiliation(s)
- Bayu Dume
- Faculty of Agrobiology, Food, and Natural Resources, Department of Agro-Environmental Chemistry and Plant Nutrition, Czech University of Life Sciences, Prague, Czech Republic
| | - Ales Hanc
- Faculty of Agrobiology, Food, and Natural Resources, Department of Agro-Environmental Chemistry and Plant Nutrition, Czech University of Life Sciences, Prague, Czech Republic
| | - Pavel Svehla
- Faculty of Agrobiology, Food, and Natural Resources, Department of Agro-Environmental Chemistry and Plant Nutrition, Czech University of Life Sciences, Prague, Czech Republic
| | - Pavel Michal
- Faculty of Agrobiology, Food, and Natural Resources, Department of Agro-Environmental Chemistry and Plant Nutrition, Czech University of Life Sciences, Prague, Czech Republic
| | - Olga Solcova
- Institute of Chemical Process Fundamentals, Czech Academy of Sciences, Prague 6, Czech Republic
| | - Abraham Demelash Chane
- Faculty of Agrobiology, Food, and Natural Resources, Department of Agro-Environmental Chemistry and Plant Nutrition, Czech University of Life Sciences, Prague, Czech Republic
| | - Abebe Nigussie
- Jimma University, College of Agriculture, Jimma, Ethiopia
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11
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Ismail SA, Abou Taleb M, Emran MA, Mowafi S, Hashem AM, El-Sayed H. Benign Felt-proofing of Wool Fibers Using a Keratinolytic Thermophilic Alkaline Protease. JOURNAL OF NATURAL FIBERS 2022; 19:3697-3709. [DOI: 10.1080/15440478.2020.1848721] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/01/2023]
Affiliation(s)
- Shaymaa A. Ismail
- Department of Chemistry of Natural and Microbial Products, Pharmaceutical and Drug Industries Research Division, National Research Centre, Dokki, Cairo, Egypt
| | - Marwa Abou Taleb
- Proteinic and Man-made Fibres Department, Textile Industries Research Division, National Research Centre, Dokki, Cairo, Egypt
| | - Mohamed A. Emran
- Department of Chemistry of Natural and Microbial Products, Pharmaceutical and Drug Industries Research Division, National Research Centre, Dokki, Cairo, Egypt
| | - Salwa Mowafi
- Proteinic and Man-made Fibres Department, Textile Industries Research Division, National Research Centre, Dokki, Cairo, Egypt
| | - Amal M. Hashem
- Department of Chemistry of Natural and Microbial Products, Pharmaceutical and Drug Industries Research Division, National Research Centre, Dokki, Cairo, Egypt
| | - Hosam El-Sayed
- Proteinic and Man-made Fibres Department, Textile Industries Research Division, National Research Centre, Dokki, Cairo, Egypt
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12
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Genome-wide analysis of Keratinibaculum paraultunense strain KD-1 T and its key genes and metabolic pathways involved in the anaerobic degradation of feather keratin. Arch Microbiol 2022; 204:634. [PMID: 36127480 DOI: 10.1007/s00203-022-03226-9] [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: 10/21/2021] [Revised: 08/29/2022] [Accepted: 08/29/2022] [Indexed: 11/02/2022]
Abstract
Keratinibaculum paraultunense strain KD-1 T (= JCM 18769 T = DSM 26752 T) is a strictly anaerobic rod-shaped bacterium. Under optimal conditions, feather keratin can be completely degraded by strain KD-1 within 24 h. Genomic sequencing showed that the genome was a single circular chromosome consisting of 2,307,997 base pairs (bp), with an average G + C content of 29.8% and no plasmids. A total of 2308 genes were annotated, accounting for 88.87% of the genomic sequence, and 1495 genes were functionally annotated. Among these, genes Kpa0144, Kpa0540, and Kpa0541 encoding the thioredoxin family members were identified, and may encode the potential disulfide reductases, with redox activity for protein disulfide bonds. Two potential keratinase-encoding genes, Kpa1675 and Kpa2139, were also identified, and corresponded to the ability of strain KD-1 to hydrolyze keratin. Strain KD-1 encoded genes involved in the heterotrophic metabolic pathways of 14 amino acids and various carbohydrates. The metabolic pathways for amino acid and carbohydrate metabolism were mapped in strain KD-1 based on KEGG annotations. The complete genome of strain KD-1 provided fundamental data for the further investigation of its physiology and genetics.
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13
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Sharma C, Timorshina S, Osmolovskiy A, Misri J, Singh R. Chicken Feather Waste Valorization Into Nutritive Protein Hydrolysate: Role of Novel Thermostable Keratinase From Bacillus pacificus RSA27. Front Microbiol 2022; 13:882902. [PMID: 35547122 PMCID: PMC9083118 DOI: 10.3389/fmicb.2022.882902] [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: 02/24/2022] [Accepted: 03/14/2022] [Indexed: 11/24/2022] Open
Abstract
Microbial keratinases exhibit a momentous role in converting keratin biowastes into exceedingly valuable protein supplements. This study reports a novel, highly stable keratinase from Bacillus pacificus RSA27 for the production of pure peptides rich in essential amino acids from chicken feathers. Purified keratinase showed a specific activity of 38.73 U/mg, 2.58-fold purification, and molecular weight of 36 kDa. Kinetic studies using a chicken feather as substrate report Km and Vmax values of 5.69 mg/ml and 142.40 μg/ml/min, respectively, suggesting significant enzyme-substrate affinity/biocatalysis. Identification and in silico structural-functional analysis of keratinase discovered the presence of distinct amino acid residues and their positions. Besides, keratinase possesses a high-affinity calcium-binding site (Asp128, Leu162, Asn164, Ile166, and Val168) and a catalytic triad of Asp119, His151, and Ser308, known attributes of serine protease (subtilisin family). Furthermore, a scale-up to 5 L fermenter revealed complete feather hydrolysis (94.5%) within 24 h with high activity (789 U/ml) and total amino acid of 153.97 μmol/ml. Finally, cytotoxicity evaluation of protein hydrolysate resulted in negligible cytotoxic effects (1.02%) on the mammalian hepatoblastoma cell line, signifying its potential biotechnological applications.
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Affiliation(s)
- Chhavi Sharma
- Amity Institute of Microbial Technology, Amity University, Noida, India
| | - Svetlana Timorshina
- Department of Microbiology, Faculty of Biology, Lomonosov Moscow State University, Moscow, Russia
| | - Alexander Osmolovskiy
- Department of Microbiology, Faculty of Biology, Lomonosov Moscow State University, Moscow, Russia
| | - Jyoti Misri
- Division of Animal Science, Indian Council of Agricultural Research, New Delhi, India
| | - Rajni Singh
- Amity Institute of Microbial Technology, Amity University, Noida, India
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14
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Ma Q, Zhang YN, Zheng X, Luan F, Han P, Zhang X, Yin Y, Wang X, Gao X. A Newly Isolated Strain Lysobacter brunescens YQ20 and Its Performance on Wool Waste Biodegradation. Front Microbiol 2022; 13:794738. [PMID: 35359724 PMCID: PMC8964289 DOI: 10.3389/fmicb.2022.794738] [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: 10/21/2021] [Accepted: 02/17/2022] [Indexed: 11/30/2022] Open
Abstract
Wool keratin is difficult to degrade as comparing to feathers because of its tough secondary structure. In order to develop an approach for high-value utilization of wool fiber waste by keratinolytic microorganisms, which is produced from shearing, weaving, and industrial processing of wool, screening of wool-degrading bacterium with high degradation efficiency were performed in this study. To this end, Lysobacter brunescens YQ20 was identified and characterized. The optimized conditions for wool degradation were pH 9.0 and 37°C with 20% liquid volume of Erlenmeyer flask. After fermentation, 15 essential amino acids were detected when wool fiber waste was fermented. The total amino acids produced from 1% wool per hour were 13.7 mg/L. The concentration was 8.6-fold higher than that produced by the strain Stenotrophomonas maltophilia BBE11-1, which had previously been reported to have the highest wool-degrading capacity. Our study reports the first Lysobacter strain that exhibits efficient wool degradation and yields higher concentrations of amino acids than previously reported strains. Whole-genome sequencing indicated that there were 18 keratinase-like genes in the genome of YQ20, which exhibited a long evolutionary distance from those of Bacillus. Therefore, L. brunescens YQ20 may have applications in the environmentally friendly management of wool waste as fertilizer in agriculture.
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Affiliation(s)
- Qinyuan Ma
- School of Life Sciences and Medicine, Shandong University of Technology, Zibo, China
| | - Ya Ning Zhang
- School of Life Sciences and Medicine, Shandong University of Technology, Zibo, China
| | - Xue Zheng
- School of Life Sciences and Medicine, Shandong University of Technology, Zibo, China
| | - Fang Luan
- School of Life Sciences and Medicine, Shandong University of Technology, Zibo, China
| | - Ping Han
- School of Life Sciences and Medicine, Shandong University of Technology, Zibo, China
| | - Xianghe Zhang
- School of Life Sciences and Medicine, Shandong University of Technology, Zibo, China
| | - Yanmiao Yin
- School of Life Sciences and Medicine, Shandong University of Technology, Zibo, China
| | - Xiaoxiao Wang
- School of Life Sciences and Medicine, Shandong University of Technology, Zibo, China
| | - Xiuzhen Gao
- School of Life Sciences and Medicine, Shandong University of Technology, Zibo, China
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15
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Anbesaw MS. Bioconversion of Keratin Wastes Using Keratinolytic Microorganisms to Generate Value-Added Products. Int J Biomater 2022; 2022:2048031. [PMID: 37251738 PMCID: PMC10212687 DOI: 10.1155/2022/2048031] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Accepted: 11/29/2021] [Indexed: 12/13/2023] Open
Abstract
The management of keratinous wastes generated from different industries is becoming a major concern across the world. In each year, more than a billion tons of keratin waste is released into the environment. Despite some trials that have been performed and utilize this waste into valuable products, still a huge amount of keratin waste from different sources is a less explored biomaterial for making valuable products. This indicates that the huge amount of keratin waste is neither disposed properly nor converted into usable products rather thrown away to the environment that causes environmental pollution. Due to the introduction of this waste associated with different pathogenic organisms into soil and water bodies, human beings and other small and large animals are affected by different diseases. Therefore, there is a need for modern and ecofriendly approaches to dispose and convert this waste into usable products. Hence, the objective of this review is to give a concise overview regarding the degradation of keratin waste by biological approaches using keratinase producing microorganisms. The review also focuses on the practical use of keratinases and the economical importance of bioconverted products of keratinous wastes for different applications. Various researches have been studied about the source, disposal mechanisms, techniques of hydrolysis, potential use, and physical and chemical properties of keratin wastes. However, there is negligible information with regard to the use of keratin wastes as media supplements for the growth of keratinolytic microorganisms and silver retrieval from photographic and used X-ray films. Hence, this review differs from other similar reviews in the literature in that it discusses these neglected concerns.
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Affiliation(s)
- Muhammed Seid Anbesaw
- Wollo University, School of Bio-Science and Technology, Department of Biotechnology, Dessie, Ethiopia
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16
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Li X, Zhang Q, Gan L, Jiang G, Tian Y, Shi B. Exoproduction and Biochemical Characterization of a Novel Serine Protease from Ornithinibacillus caprae L9 T with Hide-Dehairing Activity. J Microbiol Biotechnol 2022; 32:99-109. [PMID: 34818664 PMCID: PMC9628834 DOI: 10.4014/jmb.2108.08037] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 11/18/2021] [Accepted: 11/18/2021] [Indexed: 12/15/2022]
Abstract
This study is the first report on production and characterization of the enzyme from an Ornithinibacillus species. A 4.2-fold increase in the extracellular protease (called L9T) production from Ornithinibacillus caprae L9T was achieved through the one-factor-at-a-time approach and response surface methodological optimization. L9T protease exhibited a unique protein band with a mass of 25.9 kDa upon sodium dodecyl sulfate-polyacrylamide gel electrophoresis. This novel protease was active over a range of pH (4-13), temperatures (30-80°C) and salt concentrations (0-220 g/l), with the maximal activity observed at pH 7, 70°C and 20 g/l NaCl. Proteolytic activity was upgraded in the presence of Ag+, Ca2+ and Sr2+, but was totally suppressed by 5 mM phenylmethylsulfonyl fluoride, which suggests that this enzyme belongs to the serine protease family. L9T protease was resistant to certain common organic solvents and surfactants; particularly, 5 mM Tween 20 and Tween 80 improved the activity by 63 and 15%, respectively. More importantly, L9T protease was found to be effective in dehairing of goatskins, cowhides and rabbit-skins without damaging the collagen fibers. These properties confirm the feasibility of L9T protease in industrial applications, especially in leather processing.
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Affiliation(s)
- Xiaoguang Li
- Key Laboratory of Leather Chemistry and Engineering, Ministry of Education and College of Biomass Science and Engineering, Sichuan University, Chengdu 610065, P.R. China
| | - Qian Zhang
- Key Laboratory of Bio-Resources and Eco-Environment, Ministry of Education and College of Life Sciences, Sichuan University, Chengdu 610065, P.R. China
| | - Longzhan Gan
- Key Laboratory of Leather Chemistry and Engineering, Ministry of Education and College of Biomass Science and Engineering, Sichuan University, Chengdu 610065, P.R. China
| | - Guangyang Jiang
- Key Laboratory of Leather Chemistry and Engineering, Ministry of Education and College of Biomass Science and Engineering, Sichuan University, Chengdu 610065, P.R. China
| | - Yongqiang Tian
- Key Laboratory of Leather Chemistry and Engineering, Ministry of Education and College of Biomass Science and Engineering, Sichuan University, Chengdu 610065, P.R. China,Corresponding authors Y. Tian Phone: +86-28-85405237 Fax: +86-28-85405237 E-mail:
| | - Bi Shi
- Key Laboratory of Leather Chemistry and Engineering, Ministry of Education and College of Biomass Science and Engineering, Sichuan University, Chengdu 610065, P.R. China,
B. Shi E-mail:
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17
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Devi S, Chauhan A, Bishist R, Sankhyan N, Rana K, Sharma N. Production, partial purification and efficacy of keratinase from Bacillus halotolerans L2EN1 isolated from the poultry farm of Himachal Pradesh as a potential laundry additive. BIOCATAL BIOTRANSFOR 2022. [DOI: 10.1080/10242422.2022.2029851] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Affiliation(s)
- Sunita Devi
- Department of Basic Sciences, Dr YS Parmar University of Horticulture and Forestry Nauni, Solan, India
| | - Aishwarya Chauhan
- Department of Basic Sciences, Dr YS Parmar University of Horticulture and Forestry Nauni, Solan, India
| | - Rohit Bishist
- Department of Silviculture and Agroforestry, College of Forestry, Dr Y S Parmar University of Horticulture and Forestry, Nauni, Solan, India
| | - Neeraj Sankhyan
- Department of Basic Sciences, Dr YS Parmar University of Horticulture and Forestry Nauni, Solan, India
| | - Kavita Rana
- Department of Basic Sciences, Dr YS Parmar University of Horticulture and Forestry Nauni, Solan, India
| | - Nisha Sharma
- Department of Basic Sciences, Dr YS Parmar University of Horticulture and Forestry Nauni, Solan, India
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18
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Li X, Guo Z, Li J, Yang M, Yao S. Swelling and microwave-assisted hydrolysis of animal keratin in ionic liquids. J Mol Liq 2021. [DOI: 10.1016/j.molliq.2021.117306] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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19
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Exploring the Diversity and Biotechnological Potential of Cultured and Uncultured Coral-Associated Bacteria. Microorganisms 2021; 9:microorganisms9112235. [PMID: 34835361 PMCID: PMC8622030 DOI: 10.3390/microorganisms9112235] [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: 10/05/2021] [Revised: 10/20/2021] [Accepted: 10/24/2021] [Indexed: 11/17/2022] Open
Abstract
Coral-associated microbes are crucial for the biology of their hosts, contributing to nutrient cycling, adaptation, mitigation of toxic compounds, and biological control of pathogens. Natural products from coral-associated micro-organisms (CAM) may possess unique traits. Despite this, the use of CAM for biotechnological purposes has not yet been adequately explored. Here, we investigated the production of commercially important enzymes by 37 strains of bacteria isolated from the coral species Mussismilia braziliensis, Millepora alcicornis, and Porites astreoides. In-vitro enzymatic assays showed that up to 56% of the isolates produced at least one of the seven enzymes screened (lipase, caseinase, keratinase, cellulase, chitinase, amylase, and gelatinase); one strain, identified as Bacillus amyloliquefaciens produced all these enzymes. Additionally, coral species-specific cultured and uncultured microbial communities were identified. The phylum Firmicutes predominated among the isolates, including the genera Exiguobacterium, Bacillus, and Halomonas, among others. Next-generation sequencing and bacteria culturing produced similar but also complementary data, with certain genera detected only by one or the other method. Our results demonstrate the importance of exploring different coral species as sources of specific micro-organisms of biotechnological and industrial interest, at the same time reinforcing the economic and ecological importance of coral reefs as reservoirs of such diversity.
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20
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Orlien V, Aalaei K, Poojary MM, Nielsen DS, Ahrné L, Carrascal JR. Effect of processing on in vitro digestibility (IVPD) of food proteins. Crit Rev Food Sci Nutr 2021; 63:2790-2839. [PMID: 34590513 DOI: 10.1080/10408398.2021.1980763] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Proteins are important macronutrients for the human body to grow and function throughout life. Although proteins are found in most foods, their very dissimilar digestibility must be taking into consideration when addressing the nutritional composition of a diet. This review presents a comprehensive summary of the in vitro digestibility of proteins from plants, milk, muscle, and egg. It is evident from this work that protein digestibility greatly varies among foods, this variability being dependent not only upon the protein source, but also the food matrix and the molecular interactions between proteins and other food components (food formulation), as well as the conditions during food processing and storage. Different approaches have been applied to assess in vitro protein digestibility (IVPD), varying in both the enzyme assay and quantification method used. In general, animal proteins tend to show higher IVPD. Harsh technological treatments tend to reduce IVPD, except for plant proteins, in which thermal degradation of anti-nutritional compounds results in improved IVPD. However, in order to improve the current knowledge about protein digestibility there is a vital need for understanding dependency on a protein source, molecular interaction, processing and formulation and relationships between. Such knowledge can be used to develop new food products with enhanced protein bioaccessibility.
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Affiliation(s)
- Vibeke Orlien
- Department of Food Science, University of Copenhagen, Frederiksberg C, Denmark
| | - Kataneh Aalaei
- Department of Food Science, University of Copenhagen, Frederiksberg C, Denmark
| | - Mahesha M Poojary
- Department of Food Science, University of Copenhagen, Frederiksberg C, Denmark
| | - Dennis S Nielsen
- Department of Food Science, University of Copenhagen, Frederiksberg C, Denmark
| | - Lilia Ahrné
- Department of Food Science, University of Copenhagen, Frederiksberg C, Denmark
| | - Jorge Ruiz Carrascal
- Research Institute of Meat and Meat Products (IproCar), University of Extremadura, Cáceres, Spain
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21
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Effective bioconversion of feather-waste Keratin by Thermo-Surfactant Stable Alkaline Keratinase produced from Aspergillus sp. DHE7 with promising biotechnological application in detergent formulations. BIOCATALYSIS AND AGRICULTURAL BIOTECHNOLOGY 2021. [DOI: 10.1016/j.bcab.2021.102052] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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22
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Goda DA, Bassiouny AR, Abdel Monem NM, Soliman NA, Abdel-Fattah YR. Feather protein lysate optimization and feather meal formation using YNDH protease with keratinolytic activity afterward enzyme partial purification and characterization. Sci Rep 2021; 11:14543. [PMID: 34267231 PMCID: PMC8282803 DOI: 10.1038/s41598-021-93279-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Accepted: 06/21/2021] [Indexed: 11/30/2022] Open
Abstract
Incubation parameters used for the creation of a protein lysate from enzymatically degraded waste feathers using crude keratinase produced by the Laceyella sacchari strain YNDH were optimized using the Response Surface Methodology (RSM); amino acids quantification was also estimated. The optimization elevated the total protein to 2089.5 µg/ml through the application of the following optimal conditions: a time of 20.2 h, a feather concentration (conc.) of 3 g%, a keratinase activity of 24.5 U/100 ml, a pH of 10, and a cultivation temperature of 50 °C. The produced Feather Protein Lysate (FPL) was found to be enriched with essential and rare amino acids. Additionally, this YNDH enzyme group was partially purified, and some of its characteristics were studied. Crude enzymes were first concentrated with an Amicon Ultra 10-k centrifugal filter, and then concentrated proteins were applied to a "Q FF" strong anion column chromatography. The partially purified enzyme has an estimated molecular masses ranging from 6 to 10 kDa. The maximum enzyme activity was observed at 70 °C and for a pH of 10.4. Most characteristics of this protease/keratinase group were found to be nearly the same when the activity was measured with both casein and keratin-azure as substrates, suggesting that these three protein bands work together in order to degrade the keratin macromolecule. Interestingly, the keratinolytic activity of this group was not inhibited by ethylenediamine tetraacetic acid (EDTA), phenylmethanesulfonyl fluoride (PMSF), or iron-caused activation, indicating the presence of a mixed serine-metallo enzyme type.
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Affiliation(s)
- Doaa A Goda
- Bioprocess Development Department, Genetic Engineering and Biotechnology Research Institute (GEBRI), City of Scientific Research and Technological Applications (SRTA-City), New Burg El-Arab City, Universities and Research Institutes Zone, Alexandria, 21934, Egypt.
| | - Ahmad R Bassiouny
- Biochemistry Department, Faculty of Science, Alexandria University, Alexandria, Egypt
| | - Nihad M Abdel Monem
- Biochemistry Department, Faculty of Science, Alexandria University, Alexandria, Egypt
| | - Nadia A Soliman
- Bioprocess Development Department, Genetic Engineering and Biotechnology Research Institute (GEBRI), City of Scientific Research and Technological Applications (SRTA-City), New Burg El-Arab City, Universities and Research Institutes Zone, Alexandria, 21934, Egypt
| | - Yasser R Abdel-Fattah
- Bioprocess Development Department, Genetic Engineering and Biotechnology Research Institute (GEBRI), City of Scientific Research and Technological Applications (SRTA-City), New Burg El-Arab City, Universities and Research Institutes Zone, Alexandria, 21934, Egypt
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23
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Unveiling the keratinolytic transcriptome of the black carpet beetle (Attagenus unicolor) for sustainable poultry feather recycling. Appl Microbiol Biotechnol 2021; 105:5577-5587. [PMID: 34226961 DOI: 10.1007/s00253-021-11427-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Revised: 06/10/2021] [Accepted: 06/12/2021] [Indexed: 01/14/2023]
Abstract
The black carpet beetle (BCB) is a household pest unique in its ability to digest complex proteins such as keratin that makes up the majority of feather structure. Despite voluminous yield and high protein content ( > 85%), feathers are poorly digested by most known organisms and are thereby rendered an environmental hazard. Furthermore, keratinolytic microbial strains are typically thermophilic and therefore economically and environmentally unsustainable. Given the BCB's ability to digest wool, feathers, and other keratin-rich materials, we assembled a de novo transcriptome of larvae fed on either feathers or standard chow. All proteolytic enzymes were identified via homology to the MEROPS database and subsequently annotated for a complete overview of enzymatic activity and distribution of peptidase clans in the transcriptome. Both differential expression and sequence homology screening were then used to identify potentially keratinolytic candidates from the assembly to be used in future expression experiments. The BCB transcriptome showed a high proportion of serine (22.6%) and cysteine (18.9%) proteases as well as metallopeptidases (25.5%) compared with other insect species. Regarding differential expression, serine and metalloproteases represented a large proportion of upregulated genes in the feather-fed group, constituting 42.9% and 57.1% of upregulated proteases, respectively. Additionally, several candidate transcripts identified through homology screening showed significant sequence overlap to seven existing keratinases, indicating a strong likelihood of keratinolytic function in this organism. KEY POINTS: • A de novo transcriptome of black carpet beetle larvae was assembled. • The transcriptome consisted of 67% of serine, cysteine, and metalloproteases. • Differential transcriptomes of beetles fed feather and chow were compared.
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24
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An Integrative Bioinformatic Analysis for Keratinase Detection in Marine-Derived Streptomyces. Mar Drugs 2021; 19:md19060286. [PMID: 34063876 PMCID: PMC8224001 DOI: 10.3390/md19060286] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Revised: 05/12/2021] [Accepted: 05/18/2021] [Indexed: 01/08/2023] Open
Abstract
Keratinases present promising biotechnological applications, due to their ability to degrade keratin. Streptomyces appears as one of the main sources of these enzymes, but complete genome sequences of keratinolytic bacteria are still limited. This article reports the complete genomes of three marine-derived streptomycetes that show different levels of feather keratin degradation, with high (strain G11C), low (strain CHD11), and no (strain Vc74B-19) keratinolytic activity. A multi-step bioinformatics approach is described to explore genes encoding putative keratinases in these genomes. Despite their differential keratinolytic activity, multiplatform annotation reveals similar quantities of ORFs encoding putative proteases in strains G11C, CHD11, and Vc74B-19. Comparative genomics classified these putative proteases into 140 orthologous groups and 17 unassigned orthogroup peptidases belonging to strain G11C. Similarity network analysis revealed three network communities of putative peptidases related to known keratinases of the peptidase families S01, S08, and M04. When combined with the prediction of cellular localization and phylogenetic reconstruction, seven putative keratinases from the highly keratinolytic strain Streptomyces sp. G11C are identified. To our knowledge, this is the first multi-step bioinformatics analysis that complements comparative genomics with phylogeny and cellular localization prediction, for the prediction of genes encoding putative keratinases in streptomycetes.
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Chicken Feather Waste Hydrolysate as a Superior Biofertilizer in Agroindustry. Curr Microbiol 2021; 78:2212-2230. [PMID: 33903939 DOI: 10.1007/s00284-021-02491-z] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Accepted: 04/13/2021] [Indexed: 10/24/2022]
Abstract
Billions of tons of keratinous waste in the form of feathers, antlers, bristles, claws, hair, hoofs, horns, and wool are generated by different industries and their demolition causes environmental deterioration. Chicken feathers have 92% keratin that can be a good source of peptides, amino acids, and minerals. Traditional methods of feather hydrolysis require large energy inputs, and also reduce the content of amino acids and net protein utilization values. Biological treatment of feathers with keratinolytic microbes is a feasible and environmental favorable preference for the formulation of hydrolysate that can be used as bioactive peptides, protein supplement, livestock feed, biofertilizer, etc. The presence of amino acids, soluble proteins, and peptides in hydrolysate facilitates the growth of microbes in rhizosphere that promotes the uptake and utilization of nutrients from soil. Application of hydrolysate enhances water holding capacity, C/N ratio, and mineral content of soil. The plant growth promoting activities of hydrolysate potentiates its possible use in organic farming, and improves soil ecosystem and microbiota. This paper reviews the current scenario on the methods available for management of keratinous waste, nutritional quality of hydrolysate generated using keratinolytic microbes, and its possible application as plant growth promoter in agroindustry.
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Cheng D, Liu Y, Ngo HH, Guo W, Chang SW, Nguyen DD, Zhang S, Luo G, Bui XT. Sustainable enzymatic technologies in waste animal fat and protein management. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2021; 284:112040. [PMID: 33571854 DOI: 10.1016/j.jenvman.2021.112040] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Revised: 01/14/2021] [Accepted: 01/20/2021] [Indexed: 06/12/2023]
Abstract
Waste animal fats and proteins (WAFP) are rich in various animal by-products from food industries. On one hand, increasing production of huge amounts of WAFP brings a great challenge to their appropriate disposal, and raises severe risks to environment and life health. On the other hand, the high fat and protein contents in these animal wastes are valuable resources which can be reutilized in an eco-friendly and renewable way. Sustainable enzymatic technologies are promising methods for WAFP management. This review discussed the application of various enzymes in the conversion of WSFP to value-added biodiesel and bioactivate hydrolysates. New biotechnologies to discover novel enzymes with robust properties were proposed as well. This paper also presented the bio-utilization strategy of animal fat and protein wastes as alternative nutrient media for microorganism growth activities to yield important industrial enzymes cost-effectively.
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Affiliation(s)
- Dongle Cheng
- Centre for Technology in Water and Wastewater, School of Civil and Environmental Engineering, University of Technology Sydney, Sydney, NWS, 2007, Australia
| | - Yi Liu
- Department of Environmental Science and Engineering, Fudan University, Shanghai, 200438, China
| | - Huu Hao Ngo
- Centre for Technology in Water and Wastewater, School of Civil and Environmental Engineering, University of Technology Sydney, Sydney, NWS, 2007, Australia.
| | - Wenshan Guo
- Centre for Technology in Water and Wastewater, School of Civil and Environmental Engineering, University of Technology Sydney, Sydney, NWS, 2007, Australia; NTT Institute of Hi-Technology, Nguyen Tat Thanh University, Ho Chi Minh City, Viet Nam
| | - Soon Woong Chang
- Department of Environmental Energy Engineering, Kyonggi University, 442-760, Republic of Korea
| | - Dinh Duc Nguyen
- Department of Environmental Energy Engineering, Kyonggi University, 442-760, Republic of Korea; Institution of Research and Development, Duy Tan University, Da Nang, Viet Nam
| | - Shicheng Zhang
- Department of Environmental Science and Engineering, Fudan University, Shanghai, 200438, China
| | - Gang Luo
- Department of Environmental Science and Engineering, Fudan University, Shanghai, 200438, China
| | - Xuan Thanh Bui
- Key Laboratory of Advanced Waste Treatment Technology, Ho Chi Minh City University of Technology (HCMUT), Vietnam National University Ho Chi Minh (VNU-HCM), Ho Chi Minh City, 700000, Viet Nam
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Kang D, Huang Y, Nesme J, Herschend J, Jacquiod S, Kot W, Hansen LH, Lange L, Sørensen SJ. Metagenomic analysis of a keratin-degrading bacterial consortium provides insight into the keratinolytic mechanisms. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 761:143281. [PMID: 33190895 DOI: 10.1016/j.scitotenv.2020.143281] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Revised: 10/11/2020] [Accepted: 10/24/2020] [Indexed: 06/11/2023]
Abstract
Keratin is an insoluble fibrous protein from natural environments, which can be recycled to value-added products by keratinolytic microorganisms. A microbial consortium with efficient keratinolytic activity was previously enriched from soil, but the genetic basis behind its remarkable degradation properties was not investigated yet. To identify the metabolic pathways involved in keratinolysis and clarify the observed synergy among community members, shotgun metagenomic sequencing was performed to reconstruct metagenome-assembled genomes. More than 90% genera of the enriched bacterial consortium were affiliated to Chryseobacterium, Stenotrophomonas, and Pseudomonas. Metabolic potential and putative keratinases were predicted from the metagenomic annotation, providing the genetic basis of keratin degradation. Furthermore, metabolic pathways associated with keratinolytic processes such as amino acid metabolism, disulfide reduction and urea cycle were investigated from seven high-quality metagenome-assembled genomes, revealing the potential metabolic cooperation related to keratin degradation. This knowledge deepens the understanding of microbial keratinolytic mechanisms at play in a complex community, pinpointing the significance of synergistic interactions, which could be further used to optimize industrial keratin degradation processes.
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Affiliation(s)
- Dingrong Kang
- Section of Microbiology, Department of Biology, University of Copenhagen, Copenhagen, Denmark; TERRA Research and Teaching Centre, Microbial Processes and Interactions (MiPI), Gembloux Agro-Bio Tech, University of Liège, Gembloux, Belgium
| | - Yuhong Huang
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Building 224, Søltofts Plads, 2800 Kongens Lyngby, Denmark; Beijing Key Laboratory of Ionic Liquids Clean Process, Key Laboratory of Green Process and Engineering, State Key Laboratory of Multiphase Complex Systems, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, PR China
| | - Joseph Nesme
- Section of Microbiology, Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | - Jakob Herschend
- Section of Microbiology, Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | - Samuel Jacquiod
- Section of Microbiology, Department of Biology, University of Copenhagen, Copenhagen, Denmark; Agroécologie, AgroSup Dijon, INRA, Univ. Bourgogne Franche-Comté, France
| | - Witold Kot
- Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg, Denmark
| | - Lars Hestbjerg Hansen
- Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg, Denmark
| | - Lene Lange
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Building 224, Søltofts Plads, 2800 Kongens Lyngby, Denmark; Bioeconomy, Research & Advisory, Karensgade 5, DK-2500 Valby, Denmark
| | - Søren J Sørensen
- Section of Microbiology, Department of Biology, University of Copenhagen, Copenhagen, Denmark.
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Duman YA, Bayer Y. Kinetics and thermodynamics of keratin degradation by partially purified and encapsulated keratinase from Bacillus vallismortis DSM11031. BIOCATAL BIOTRANSFOR 2021. [DOI: 10.1080/10242422.2021.1876678] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Affiliation(s)
- Yonca Avci Duman
- Department of Chemistry, Faculty of Arts and Sciences, Kocaeli University, Kocaeli, Turkiye
| | - Yasemin Bayer
- Department of Chemistry, Faculty of Arts and Sciences, Kocaeli University, Kocaeli, Turkiye
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Bio-degradation of Feathers Waste by the Staphylococcus epidermidis P3A. JOURNAL OF PURE AND APPLIED MICROBIOLOGY 2020. [DOI: 10.22207/jpam.14.4.37] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Development of industrialization is directly proportional to the development of nations. Rising industrializations also increase the pollutions. One of them is poultry industry which discharges a huge amount of keratinous waste. The present study focused on the selection of feather degrading bacteria from Barshi region of Maharashtra. Bacterial strains were grown in whole feather broth medium. Out of 16 proteolytic bacterial isolates, 9 feather degrading isolates were selected from the Parande road side feather waste dumping area. Among these isolates, P3A was selected and classified on the basis of morphological and biochemical analysis. 16S rRNA studies confirmed that the isolated strain was Staphylococcus epidermidis. Staphylococcus epidermidis P3A shows 84% feather degradation and 72 U/ml maximum keratinase activity after 96 hrs. The isolate shows potential use in feather waste disposal methods which are safe and environment friendly.
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Optimization of Keratinase Production and Utilization of Bacillus pumilus for Feather Degradation. JOURNAL OF PURE AND APPLIED MICROBIOLOGY 2020. [DOI: 10.22207/jpam.14.4.26] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Soil samples were collected from the feather dumped area where Bacillus pumilus was isolated and used for keratinase production and keratinolytic activity. In the optimization study, optimal condition for enzyme production was observed at 144 h, pH 7, temperature 37°C. The organism was utilized for feather degradation study. The maximum degradation of 57% was obtained at 37°C, pH 7 and 6 days incubation. The size of keratinase was determined by SDS- PAGE and was observed as 52 KDa.
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Nnolim NE, Udenigwe CC, Okoh AI, Nwodo UU. Microbial Keratinase: Next Generation Green Catalyst and Prospective Applications. Front Microbiol 2020; 11:580164. [PMID: 33391200 PMCID: PMC7775373 DOI: 10.3389/fmicb.2020.580164] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2020] [Accepted: 11/30/2020] [Indexed: 12/18/2022] Open
Abstract
The search for novel renewable products over synthetics hallmarked this decade and those of the recent past. Most economies that are prospecting on biodiversity for improved bio-economy favor renewable resources over synthetics for the potential opportunity they hold. However, this field is still nascent as the bulk of the available resources are non-renewable based. Microbial metabolites, emphasis on secondary metabolites, are viable alternatives; nonetheless, vast microbial resources remain under-exploited; thus, the need for a continuum in the search for new products or bio-modifying existing products for novel functions through an efficient approach. Environmental distress syndrome has been identified as a factor that influences the emergence of genetic diversity in prokaryotes. Still, the process of how the change comes about is poorly understood. The emergence of new traits may present a high prospect for the industrially viable organism. Microbial enzymes have prominence in the bio-economic space, and proteases account for about sixty percent of all enzyme market. Microbial keratinases are versatile proteases which are continuously gaining momentum in biotechnology owing to their effective bio-conversion of recalcitrant keratin-rich wastes and sustainable implementation of cleaner production. Keratinase-assisted biodegradation of keratinous materials has revitalized the prospects for the utilization of cost-effective agro-industrial wastes, as readily available substrates, for the production of high-value products including amino acids and bioactive peptides. This review presented an overview of keratin structural complexity, the potential mechanism of keratin biodegradation, and the environmental impact of keratinous wastes. Equally, it discussed microbial keratinase; vis-à-vis sources, production, and functional properties with considerable emphasis on the ecological implication of microbial producers and catalytic tendency improvement strategies. Keratinase applications and prospective high-end use, including animal hide processing, detergent formulation, cosmetics, livestock feed, and organic fertilizer production, were also articulated.
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Affiliation(s)
- 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
| | - Chibuike C. Udenigwe
- School of Nutrition Sciences, Faculty of Health Sciences, University of Ottawa, Ottawa, ON, Canada
| | - Anthony I. Okoh
- 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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Alahyaribeik S, Ullah A. Effects of Ultrasound‐Assisted Alkaline Extraction on Antioxidant Activity and Functional Characteristics of Chicken Feather Keratin Peptides. ChemistrySelect 2020. [DOI: 10.1002/slct.202002887] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Samira Alahyaribeik
- Department of Agricultural, Food and Nutritional Science University of Alberta Edmonton Alberta Canada T5G2P5
- Department of Animal and Poultry Science College of Aburaihan University of Tehran Pakdasht Iran 33916-53755
| | - Aman Ullah
- Department of Agricultural, Food and Nutritional Science University of Alberta Edmonton Alberta Canada T5G2P5
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Tiwari U, Ganesan NG, Junnarkar J, Rangarajan V. Toward the formulation of bio-cosmetic nanoemulsions: from plant-derived to microbial-derived ingredients. J DISPER SCI TECHNOL 2020. [DOI: 10.1080/01932691.2020.1847664] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Utkarsh Tiwari
- Department of Chemical Engineering, Birla Institute of Technology and Science-Pilani, K.K. Birla Goa Campus, Zuarinagar, Goa, India
| | - Neela Gayathri Ganesan
- Department of Chemical Engineering, Birla Institute of Technology and Science-Pilani, K.K. Birla Goa Campus, Zuarinagar, Goa, India
| | - Jui Junnarkar
- Department of Chemical Engineering, Birla Institute of Technology and Science-Pilani, K.K. Birla Goa Campus, Zuarinagar, Goa, India
| | - Vivek Rangarajan
- Department of Chemical Engineering, Birla Institute of Technology and Science-Pilani, K.K. Birla Goa Campus, Zuarinagar, Goa, India
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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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Czapela FF, Kubeneck S, Preczeski KP, Dalastra C, Scapini T, Bonatto C, Stefanski FS, Camargo AF, Zanivan J, Mossi AJ, Fongaro G, Treichel H. Reactional ultrasonic systems and microwave irradiation for pretreatment of agro-industrial waste to increase enzymatic activity. BIORESOUR BIOPROCESS 2020. [DOI: 10.1186/s40643-020-00338-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
AbstractPretreatment of keratinous residues using an ultrasonic reaction system provides greater enzymatic production in less time. This is a promising technology for measuring enzyme activity and microwave processes. In the present work, an ultrasonic probe reaction system was used to evaluate the potential of swine hair pretreatment. The pretreated material was submerged with non-pretreated residues for 9 days to obtain the enzyme. Enzyme activity was measured in the extracts obtained using the ultrasonic probe, ultrasonic bath, and microwave. We also used the enzymatic concentration technique with NaCl and acetone. Homemade enzymatic extracts were evaluated for their ability to degrade swine hair and chicken feathers by comparing them with the activities commercial enzymes. Macrobeads gave greater energy dissipation in less time, providing greater enzyme activity (50.8 U/mL over 3 days). In terms of waste degradation, non-pretreated swine hair was more promising. The ultrasonic probe reaction system had the potential to evaluate increased enzyme activity (38.4% relative activity) and the enzyme concentration increased activity by 53.5%. The homemade enzymatic extract showed promise for degradation of keratinous residues.
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Feroz S, Muhammad N, Ranayake J, Dias G. Keratin - Based materials for biomedical applications. Bioact Mater 2020; 5:496-509. [PMID: 32322760 PMCID: PMC7171262 DOI: 10.1016/j.bioactmat.2020.04.007] [Citation(s) in RCA: 106] [Impact Index Per Article: 26.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Revised: 03/27/2020] [Accepted: 04/06/2020] [Indexed: 12/22/2022] Open
Abstract
Keratin constitutes the major component of the feather, hair, hooves, horns, and wool represents a group of biological material having high cysteine content (7-13%) as compared to other structural proteins. Keratin -based biomaterials have been investigated extensively over the past few decades due to their intrinsic biological properties and excellent biocompatibility. Unlike other natural polymers such as starch, collagen, chitosan, the complex three-dimensional structure of keratin requires the use of harsh chemical conditions for their dissolution and extraction. The most commonly used methods for keratin extraction are oxidation, reduction, steam explosion, microbial method, microwave irradiation and use of ionic liquids. Keratin -based materials have been used extensively for various biomedical applications such as drug delivery, wound healing, tissue engineering. This review covers the structure, properties, history of keratin research, methods of extraction and some recent advancements related to the use of keratin derived biomaterials in the form of a 3-D scaffold, films, fibers, and hydrogels.
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Affiliation(s)
- Sandleen Feroz
- Department of Anatomy, School of Biomedical Sciences University of Otago, Otago, 9016, New Zealand
| | - Nawshad Muhammad
- Interdisciplinary Research Centre in Biomedical Materials (IRCBM), COMSATS University Islamabad, Lahore Campus, Pakistan
| | - Jithendra Ranayake
- Department of Anatomy, School of Biomedical Sciences University of Otago, Otago, 9016, New Zealand
| | - George Dias
- Department of Anatomy, School of Biomedical Sciences University of Otago, Otago, 9016, New Zealand
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Su C, Gong JS, Ye JP, He JM, Li RY, Jiang M, Geng Y, Zhang Y, Chen JH, Xu ZH, Shi JS. Enzymatic Extraction of Bioactive and Self-Assembling Wool Keratin for Biomedical Applications. Macromol Biosci 2020; 20:e2000073. [PMID: 32691954 DOI: 10.1002/mabi.202000073] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2020] [Revised: 05/20/2020] [Indexed: 12/30/2022]
Abstract
Keratin is widely recognized as a high-quality renewable protein resource for biomedical applications. Despite their extensive existence, keratin resources such as feathers, wool, and hair exhibit high stability and mechanical properties because of their high disulfide bond content. Consequently, keratin extraction is challenging and its application is greatly hindered. In this work, a biological extraction strategy is proposed for the preparation of bioactive keratin and the fabrication of self-assembled keratin hydrogels (KHs). Based on moderate and controlled hydrolysis by keratinase, keratin with a high molecular weight of approximately 45 and 28 kDa that retain its intrinsic bioactivities is obtained. The keratin products show excellent ability to promote cell growth and migration and are conferred with significant antioxidant ability because of their intrinsically high cysteine content. In addition, without the presence of any cross-linking agent, the extracted keratin can self-assemble into injectable hydrogels. The KHs exhibit a porous network structure and 3D culture ability, showing potential in promoting wound healing. This enzyme-driven keratin extraction strategy opens up a new approach for the preparation of keratin that can self-assemble into injectable hydrogels for biomedical engineering.
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Affiliation(s)
- Chang Su
- C. Su, Dr. J.-S. Gong, J.-P. Ye, J.-M. He, Dr. R.-Y. Li, M. Jiang, Dr. Y. Geng, Dr. Y. Zhang, Prof. J.-H. Chen, Prof. J.-S, Shi, Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Pharmaceutical Sciences, Jiangnan University, Wuxi, 214122, P. R. China
| | - Jin-Song Gong
- C. Su, Dr. J.-S. Gong, J.-P. Ye, J.-M. He, Dr. R.-Y. Li, M. Jiang, Dr. Y. Geng, Dr. Y. Zhang, Prof. J.-H. Chen, Prof. J.-S, Shi, Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Pharmaceutical Sciences, Jiangnan University, Wuxi, 214122, P. R. China
| | - Jin-Peng Ye
- C. Su, Dr. J.-S. Gong, J.-P. Ye, J.-M. He, Dr. R.-Y. Li, M. Jiang, Dr. Y. Geng, Dr. Y. Zhang, Prof. J.-H. Chen, Prof. J.-S, Shi, Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Pharmaceutical Sciences, Jiangnan University, Wuxi, 214122, P. R. China
| | - Ji-Meng He
- C. Su, Dr. J.-S. Gong, J.-P. Ye, J.-M. He, Dr. R.-Y. Li, M. Jiang, Dr. Y. Geng, Dr. Y. Zhang, Prof. J.-H. Chen, Prof. J.-S, Shi, Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Pharmaceutical Sciences, Jiangnan University, Wuxi, 214122, P. R. China
| | - Rui-Yi Li
- C. Su, Dr. J.-S. Gong, J.-P. Ye, J.-M. He, Dr. R.-Y. Li, M. Jiang, Dr. Y. Geng, Dr. Y. Zhang, Prof. J.-H. Chen, Prof. J.-S, Shi, Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Pharmaceutical Sciences, Jiangnan University, Wuxi, 214122, P. R. China
| | - Min Jiang
- C. Su, Dr. J.-S. Gong, J.-P. Ye, J.-M. He, Dr. R.-Y. Li, M. Jiang, Dr. Y. Geng, Dr. Y. Zhang, Prof. J.-H. Chen, Prof. J.-S, Shi, Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Pharmaceutical Sciences, Jiangnan University, Wuxi, 214122, P. R. China
| | - Yan Geng
- C. Su, Dr. J.-S. Gong, J.-P. Ye, J.-M. He, Dr. R.-Y. Li, M. Jiang, Dr. Y. Geng, Dr. Y. Zhang, Prof. J.-H. Chen, Prof. J.-S, Shi, Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Pharmaceutical Sciences, Jiangnan University, Wuxi, 214122, P. R. China
| | - Yan Zhang
- C. Su, Dr. J.-S. Gong, J.-P. Ye, J.-M. He, Dr. R.-Y. Li, M. Jiang, Dr. Y. Geng, Dr. Y. Zhang, Prof. J.-H. Chen, Prof. J.-S, Shi, Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Pharmaceutical Sciences, Jiangnan University, Wuxi, 214122, P. R. China
| | - Jing-Hua Chen
- C. Su, Dr. J.-S. Gong, J.-P. Ye, J.-M. He, Dr. R.-Y. Li, M. Jiang, Dr. Y. Geng, Dr. Y. Zhang, Prof. J.-H. Chen, Prof. J.-S, Shi, Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Pharmaceutical Sciences, Jiangnan University, Wuxi, 214122, P. R. China
| | - Zheng-Hong Xu
- Prof. Z.-H. Xu, National Engineering Laboratory for Cereal Fermentation Technology, School of Biotechnology, Jiangnan University, Wuxi, 214122, P. R. China.,Prof. Z.-H. Xu, Jiangsu Provincial Research Center for Bioactive Product Processing Technology, Jiangnan University, Wuxi, 214122, P. R. China
| | - Jin-Song Shi
- C. Su, Dr. J.-S. Gong, J.-P. Ye, J.-M. He, Dr. R.-Y. Li, M. Jiang, Dr. Y. Geng, Dr. Y. Zhang, Prof. J.-H. Chen, Prof. J.-S, 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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Graves GR, Matterson KO, Milensky CM, Schmidt BK, O'Mahoney MJV, Drovetski SV. Does solar irradiation drive community assembly of vulture plumage microbiotas? Anim Microbiome 2020; 2:24. [PMID: 33499993 PMCID: PMC7807431 DOI: 10.1186/s42523-020-00043-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Accepted: 06/30/2020] [Indexed: 02/08/2023] Open
Abstract
BACKGROUND Stereotyped sunning behaviour in birds has been hypothesized to inhibit keratin-degrading bacteria but there is little evidence that solar irradiation affects community assembly and abundance of plumage microbiota. The monophyletic New World vultures (Cathartiformes) are renowned for scavenging vertebrate carrion, spread-wing sunning at roosts, and thermal soaring. Few avian species experience greater exposure to solar irradiation. We used 16S rRNA sequencing to investigate the plumage microbiota of wild individuals of five sympatric species of vultures in Guyana. RESULTS The exceptionally diverse plumage microbiotas (631 genera of Bacteria and Archaea) were numerically dominated by bacterial genera resistant to ultraviolet (UV) light, desiccation, and high ambient temperatures, and genera known for forming desiccation-resistant endospores (phylum Firmicutes, order Clostridiales). The extremophile genera Deinococcus (phylum Deinococcus-Thermus) and Hymenobacter (phylum, Bacteroidetes), rare in vertebrate gut microbiotas, accounted for 9.1% of 2.7 million sequences (CSS normalized and log2 transformed). Five bacterial genera known to exhibit strong keratinolytic capacities in vitro (Bacillus, Enterococcus, Pseudomonas, Staphylococcus, and Streptomyces) were less abundant (totaling 4%) in vulture plumage. CONCLUSIONS Bacterial rank-abundance profiles from melanized vulture plumage have no known analog in the integumentary systems of terrestrial vertebrates. The prominence of UV-resistant extremophiles suggests that solar irradiation may play a significant role in the assembly of vulture plumage microbiotas. Our results highlight the need for controlled in vivo experiments to test the effects of UV on microbial communities of avian plumage.
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Affiliation(s)
- Gary R Graves
- Department of Vertebrate Zoology, National Museum of Natural History, Smithsonian Institution, Washington, DC, 20013, USA.
- Center for Macroecology, Evolution, and Climate, Globe Institute, University of Copenhagen, DK-2100, Copenhagen Ø, Denmark.
| | - Kenan O Matterson
- Department of Biological, Geological and Environmental Sciences (BiGeA), University of Bologna, 48100, Ravenna, Italy
| | - Christopher M Milensky
- Department of Vertebrate Zoology, National Museum of Natural History, Smithsonian Institution, Washington, DC, 20013, USA
| | - Brian K Schmidt
- Department of Vertebrate Zoology, National Museum of Natural History, Smithsonian Institution, Washington, DC, 20013, USA
| | - Michael J V O'Mahoney
- Department of Invertebrate Zoology, National Museum of Natural History, Smithsonian Institution, Washington, DC, 20013, USA
| | - Sergei V Drovetski
- Laboratories of Analytical Biology, National Museum of Natural History, Smithsonian Institution, Washington, DC, 20013, USA
- Current address: USGS Patuxent Wildlife Research Center, 10300 Baltimore Avenue, BARC-East Bldg. 308, Beltsville, MD, 20705, USA
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Biochemical characterization of an alkaline surfactant-stable keratinase from a new keratinase producer, Bacillus zhangzhouensis. Extremophiles 2020; 24:693-704. [PMID: 32617734 DOI: 10.1007/s00792-020-01187-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2020] [Accepted: 06/26/2020] [Indexed: 01/20/2023]
Abstract
A new keratinase producer, Bacillus sp. BK111, isolated from a poultry feather was identified as Bacillus zhangzhouensis, which is the first report for its keratinolytic activity. The keratinase production was optimized, followed by the enzyme purification and characterization using biochemical assays. A 2.34-fold increase was observed in the enzyme production under optimized conditions. The enzyme was characterized as a serine protease with 42 kDa molecular weight, stable in a wide range of temperature and pH with maximum keratinolytic activity at 60 °C and pH 9.5. The enzyme had a wide range of different substrates with the best performance on the feather meal substrate. Metal ions of Ca2+, K+, Na+ and Mn2+ enhanced the enzyme activity. The enzyme showed a great deal of stability in the presence of ethanol, methanol, acetone, 2-propanol, dimethyl sulfoxide, Tween-80 and Triton X-100. Dithiothreitol (DTT), as a reducing agent, caused a twofold increase in keratinolytic activity. The half-life of the enzyme at optimum temperature was calculated to be 125 min and the ratio of keratinolytic:caseinolytic for the enzyme was 0.8. Our results showed the remarkable features of the enzyme that make it suitable for biotechnological usages.
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Huang Y, Łężyk M, Herbst FA, Busk PK, Lange L. Novel keratinolytic enzymes, discovered from a talented and efficient bacterial keratin degrader. Sci Rep 2020; 10:10033. [PMID: 32572051 PMCID: PMC7308268 DOI: 10.1038/s41598-020-66792-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Accepted: 05/21/2020] [Indexed: 11/30/2022] Open
Abstract
Huge quantities of keratinaceous waste are a substantial and almost totally unexploited protein resource which could be upgraded for use as high value-added products by efficient keratinolytic enzymes. In this study, we found that Bacillus sp. 8A6 can efficiently degrade chicken feather after 24 h growth. According to phylogenetic analysis, the strain (formerly identified as Bacillus pumilus 8A6) belongs to the B. pumilus species clade but it is more closely related to B. safensis. Hotpep predicted 233 putative proteases from Bacillus sp. 8A6 genome. Proteomic analysis of culture broths from Bacillus sp. 8A6 cultured on chicken feathers or on a mixture of bristles and hooves showed high abundance of proteins with functions related to peptidase activity. Five proteases (one from family M12, one from family S01A, two from family S08A and one from family T3) and four oligopeptide and dipeptide binding proteins were highly expressed when Bacillus sp. 8A6 was grown in keratin media compared to LB medium. This study is the first to report that bacterial proteases in families M12, S01A and T3 are involved in keratin degradation together with proteases from family S08.
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Affiliation(s)
- Yuhong Huang
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Building 224, Søltofts Plads, 2800, Kongens Lyngby, Denmark
- Beijing Key Laboratory of Ionic Liquids Clean Process, Key Laboratory of Green Process and Engineering, State Key Laboratory of Multiphase Complex Systems, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, 100190, P. R. China
| | - Mateusz Łężyk
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Building 224, Søltofts Plads, 2800, Kongens Lyngby, Denmark
- Water Supply and Bioeconomy Division, Faculty of Environmental Engineering and Energy, Poznan University of Technology, Berdychowo 4, 60-965, Poznan, Poland
| | - Florian-Alexander Herbst
- Center for Microbial Communities, Department of Chemistry and Bioscience, Aalborg University, Fredrik Bajers Vej 7H, 9220, Aalborg East, Denmark
| | - Peter Kamp Busk
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Building 224, Søltofts Plads, 2800, Kongens Lyngby, Denmark
- Department of Science and Environment, Roskilde University, Universitetsvej 1, 4000, Roskilde, Denmark
| | - Lene Lange
- Department of Biotechnology and Biomedicine, Technical University of Denmark, Building 224, Søltofts Plads, 2800, Kongens Lyngby, Denmark.
- Bioeconomy, Research & Advisory, Karensgade 5, DK-2500, Valby, Denmark.
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Duan Y, Awasthi SK, Liu T, Pandey A, Zhang Z, Kumar S, Awasthi MK. Succession of keratin-degrading bacteria and associated health risks during pig manure composting. JOURNAL OF CLEANER PRODUCTION 2020; 258:120624. [DOI: 10.1016/j.jclepro.2020.120624] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/20/2023]
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42
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Ye JP, Gong JS, Su C, Liu YG, Jiang M, Pan H, Li RY, Geng Y, Xu ZH, Shi JS. Fabrication and characterization of high molecular keratin based nanofibrous membranes for wound healing. Colloids Surf B Biointerfaces 2020; 194:111158. [PMID: 32540765 DOI: 10.1016/j.colsurfb.2020.111158] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Revised: 05/16/2020] [Accepted: 05/26/2020] [Indexed: 12/24/2022]
Abstract
Keratin is widely used in the biomaterial application, but the keratin prepared by the physical or chemical approach has relatively low molecular weight and mechanical properties. Here we report the preparation of high molecular keratin (HMK) with molecular weight of 120 kDa via multi-enzyme cascade pathway and its application in wound healing. Briefly, we prepared the soluble keratin from wool by keratinase and improved the molecular weight of keratin by transglutaminase (TGase). The HMK was coelectrospun with poly(3-hydroxybutyric acid-co-3-hydroxyvaleric acid) (PHBV) and the prepared nanofibrous mats demonstrated improved mechanical properties. Ag nanoparticles (AgNPs) were synthesized on the nanofibers via in situ bioreduction, using the above-mentioned keratinase as the reducing agent. It is demonstrated that the PHBV/HMK/AgNPs nanofibrous mats possess favorable antibacterial properties and good biocompatibility. Moreover, in vivo wound healing assessment, the PHBV/HMK/AgNPs membrane displayed better wound healing ability than the control group. These results indicate that PHBV/HMK/AgNPs mats exhibit significant potential in tissue engineering.
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Affiliation(s)
- Jin-Peng Ye
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Pharmaceutical Sciences, Jiangnan University, Wuxi214122, PR China
| | - Jin-Song Gong
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Pharmaceutical Sciences, Jiangnan University, Wuxi214122, PR China.
| | - Chang Su
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Pharmaceutical Sciences, Jiangnan University, Wuxi214122, PR China
| | - Yan-Ge Liu
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Pharmaceutical Sciences, Jiangnan University, Wuxi214122, PR China
| | - Min Jiang
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Pharmaceutical Sciences, Jiangnan University, Wuxi214122, PR China
| | - Huaping Pan
- Integrated Chinese and Western Medicine Oncology Research Center, Jiangxi University of Traditional Chinese Medicine, Nanchang330004, PR China
| | - Rui-Yi Li
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Pharmaceutical Sciences, Jiangnan University, Wuxi214122, PR China
| | - Yan Geng
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Pharmaceutical Sciences, Jiangnan University, Wuxi214122, PR China
| | - Zheng-Hong Xu
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Pharmaceutical Sciences, Jiangnan University, Wuxi214122, PR China; National Engineering Laboratory for Cereal Fermentation Technology, School of Biotechnology, Jiangnan University, Wuxi214122, PR China; Jiangsu Provincial Research Center for Bioactive Product Processing Technology, Jiangnan University, Wuxi214122, PR China
| | - Jin-Song Shi
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Pharmaceutical Sciences, Jiangnan University, Wuxi214122, PR China.
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Nnolim NE, Okoh AI, Nwodo UU. Proteolytic bacteria isolated from agro-waste dumpsites produced keratinolytic enzymes. ACTA ACUST UNITED AC 2020; 27:e00483. [PMID: 32514407 PMCID: PMC7267708 DOI: 10.1016/j.btre.2020.e00483] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Revised: 05/28/2020] [Accepted: 05/28/2020] [Indexed: 11/27/2022]
Abstract
Proteolytic bacteria were isolated from agro-waste dumpsites. The isolates degraded intact feathers and produced keratinases in basal media. Feather degradation generated high concentration of free thiol containing groups. The remarkable thiol concentrations suggest keratinous waste valorisation potential of these bacteria. The isolates were identified through 16S rDNA sequence as Bacillus spp. and Arthrobacter sp.
Microbial bioconversion of carbonoclastic materials is an efficient tool for the exploitation and valorization of underutilized agro-industrial wastes. The agro-industrial sector accumulates tones of keratinous wastes biomass which may be valorized into high value products. Consequently, the keratinolytic potentials of some bacteria isolated from terrestrial milieu was evaluated. Soil samples were collected from dumpsites, keratinase producing bacteria were isolated. Bacterial species were identified through 16S rRNA gene sequences. The keratinase activity was assessed in relation to thiol formation, percentage feather degradation and quantitation of keratinase produced. Keratinolytic bacteria were identified as Bacillus spp. (accession numbers: MG214989 – MG214992, MG214997, MG214998, MG215000, MG215002–MG215005) and Arthrobacter sp. (accession numbers; MG215001). The degree of chicken feather degradation ranged from 61.5 ± 0.71 % to 85.0 ± 1.41 %. Similarly, the activity of keratinase, total protein and thiol group ranged from 198.18 ± 15.43–731.83 ± 14.14 U/mL; 0.09 ± 0.01–0.87 ± 0.05 mg/mL; and 0.69 ± 0.12–2.89 ± 0.11 mM respectively. Notably, Bacillus sp. Nnolim-K1 displayed the best keratinolytic potential with extracellular keratinase activity and feather degradation of 731.83 ± 14.14 U/mL and 85.0 ± 1.41 % respectively, and that is an indication of a potential relevance biotechnologically.
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Affiliation(s)
- Nonso E Nnolim
- SA-MRC 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 1314, Alice, 5700, Eastern Cape, South Africa
| | - Anthony I Okoh
- SA-MRC 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 1314, Alice, 5700, Eastern Cape, South Africa
| | - Uchechukwu U Nwodo
- SA-MRC 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 1314, Alice, 5700, Eastern Cape, South Africa
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Peng Z, Mao X, Zhang J, Du G, Chen J. Biotransformation of keratin waste to amino acids and active peptides based on cell-free catalysis. BIOTECHNOLOGY FOR BIOFUELS 2020; 13:61. [PMID: 32266007 PMCID: PMC7110813 DOI: 10.1186/s13068-020-01700-4] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/12/2019] [Accepted: 03/24/2020] [Indexed: 06/11/2023]
Abstract
BACKGROUND Keratin is the primary constituent of the vertebrate epidermis and epidermal appendages, as well as the main waste product generated during poultry processing from feathers, hair, scales, nails, etc. Keratin is generally hard, stubborn and difficult to hydrolyze; however, it is also inexpensive and contains more than 85% protein. Currently, tens of millions of tons of keratin waste are produced each year worldwide; however, no effective methods for the recovery of keratin waste have been reported thus far, making such research urgent. Keratinase has been reported to be useful for keratin waste recovery; however, nearly all keratinases are unable to hydrolyze keratin after they are detached from living cell systems. This may be due to low keratinase activity and lack of synergistic factors. RESULTS Herein, the keratinase gene from Bacillus licheniformis BBE11-1 was successfully expressed in Bacillus subtilis WB600, allowing for improved activity of the recombinant keratinase KerZ1 to 45.14 KU/mL via promoter substitution and screening of the ribosome-binding sites. Further, real-time control of temperature, pH, dissolved oxygen, and feed strategy allowed the activity of KerZ1 to reach 426.60 KU/mL in a 15-L fermenter, accounting for a 3552-fold increase compared to the wild-type keratinase (120.1 U/mL). Most importantly, we proposed a method based on the synergistic action of keratinase KerZ1 and sodium sulfite, to hydrolyze feathers into amino acids. In specific, 100 g/L of feather waste can be successfully converted into 56.6% amino acids within 12 h, while supporting the production of dozens of bioactive peptides. CONCLUSIONS The activity of recombinant keratinase can be greatly enhanced via transcription and translational regulation in Bacillus subtilis. The synergistic action of keratinase and sulfite can rapidly degrade feather waste and produce amino acids and polypeptides.
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Affiliation(s)
- Zheng Peng
- School of Biotechnology, Jiangnan University, 1800 Lihu Road, Wuxi, 214122 China
- Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, 1800 Lihu Road, Wuxi, 214122 China
| | - Xinzhe Mao
- School of Biotechnology, Jiangnan University, 1800 Lihu Road, Wuxi, 214122 China
- Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, 1800 Lihu Road, Wuxi, 214122 China
| | - Juan Zhang
- School of Biotechnology, Jiangnan University, 1800 Lihu Road, Wuxi, 214122 China
- Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, 1800 Lihu Road, Wuxi, 214122 China
| | - Guocheng Du
- School of Biotechnology, Jiangnan University, 1800 Lihu Road, Wuxi, 214122 China
- Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, 1800 Lihu Road, Wuxi, 214122 China
| | - Jian Chen
- School of Biotechnology, Jiangnan University, 1800 Lihu Road, Wuxi, 214122 China
- National Engineering Laboratory for Cereal Fermentation Technology, Jiangnan University, 1800 Lihu Road, Wuxi, 214122 China
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Hassan MA, Abol-Fotouh D, Omer AM, Tamer TM, Abbas E. Comprehensive insights into microbial keratinases and their implication in various biotechnological and industrial sectors: A review. Int J Biol Macromol 2020; 154:567-583. [PMID: 32194110 DOI: 10.1016/j.ijbiomac.2020.03.116] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Revised: 03/11/2020] [Accepted: 03/13/2020] [Indexed: 12/25/2022]
Abstract
Enormous masses of keratinous wastes are annually accumulated in the environment as byproducts of poultry processing and agricultural wastes. Keratin is a recalcitrant fibrous protein, which represents the major constituent of various keratin-rich wastes, which released into the environment in the form of feathers, hair, wool, bristle, and hooves. Chemical treatment methods of these wastes resulted in developing many hazardous gases and toxins to the public health, in addition to the destruction of several amino acids. Accordingly, microbial keratinases have been drawing much interest as an eco-friendly approach to convert keratinous wastes into valuable products. Numerous keratinolytic microorganisms have been identified, which revealed the competence to hydrolyze keratins into peptides and amino acids. Several types of keratinolytic proteases have been produced that possess diverse biochemical characteristics, conferring them the versatility for implementing in multifarious applications such as detergents, leather and textile industries, animal feeding, and production of bio-fertilizers, in addition to medical and pharmaceutical treatments. This review article emphasizes the significance of keratinases and keratinase based-products via comprehensive insights into the keratin structure, diversity of keratinolytic microorganisms, and mechanisms of keratin hydrolysis. Furthermore, we discuss the biochemical properties of the produced keratinases and their feasible applications in diverse disciplines.
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Affiliation(s)
- Mohamed A Hassan
- Protein Research Department, Genetic Engineering and Biotechnology Research Institute (GEBRI), City of Scientific Research and Technological Applications (SRTA-City), New Borg El-Arab City, P.O. Box: 21934, Alexandria, Egypt.
| | - Deyaa Abol-Fotouh
- Electronic Materials Researches Department, Advanced Technology and New Materials Research Institute (ATNMRI), City of Scientific Research and Technological Applications (SRTA-City), New Borg El-Arab City, P.O. Box: 21934, Alexandria, Egypt
| | - Ahmed M Omer
- Polymer Materials Research Department, Advanced Technology and New Materials Research Institute (ATNMRI), City of Scientific Research and Technological Applications (SRTA-City), New Borg El-Arab City, P.O. Box: 21934, Alexandria, Egypt
| | - Tamer M Tamer
- Polymer Materials Research Department, Advanced Technology and New Materials Research Institute (ATNMRI), City of Scientific Research and Technological Applications (SRTA-City), New Borg El-Arab City, P.O. Box: 21934, Alexandria, Egypt
| | - Eman Abbas
- Zoology Department, Faculty of Science, Alexandria University, Alexandria, Egypt
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Challenges and Opportunities in Identifying and Characterising Keratinases for Value-Added Peptide Production. Catalysts 2020. [DOI: 10.3390/catal10020184] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Keratins are important structural proteins produced by mammals, birds and reptiles. Keratins usually act as a protective barrier or a mechanical support. Millions of tonnes of keratin wastes and low value co-products are generated every year in the poultry, meat processing, leather and wool industries. Keratinases are proteases able to breakdown keratin providing a unique opportunity of hydrolysing keratin materials like mammalian hair, wool and feathers under mild conditions. These mild conditions ameliorate the problem of unwanted amino acid modification that usually occurs with thermochemical alternatives. Keratinase hydrolysis addresses the waste problem by producing valuable peptide mixes. Identifying keratinases is an inherent problem associated with the search for new enzymes due to the challenge of predicting protease substrate specificity. Here, we present a comprehensive review of twenty sequenced peptidases with keratinolytic activity from the serine protease and metalloprotease families. The review compares their biochemical activities and highlights the difficulties associated with the interpretation of these data. Potential applications of keratinases and keratin hydrolysates generated with these enzymes are also discussed. The review concludes with a critical discussion of the need for standardized assays and increased number of sequenced keratinases, which would allow a meaningful comparison of the biochemical traits, phylogeny and keratinase sequences. This deeper understanding would facilitate the search of the vast peptidase family sequence space for novel keratinases with industrial potential.
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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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48
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Li Q. Progress in Microbial Degradation of Feather Waste. Front Microbiol 2019; 10:2717. [PMID: 31866957 PMCID: PMC6906142 DOI: 10.3389/fmicb.2019.02717] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2019] [Accepted: 11/08/2019] [Indexed: 12/31/2022] Open
Abstract
Feathers are a major by-product of the poultry industry. They are mainly composed of keratins which have wide applications in different fields. Due to the increasing production of feathers from poultry industries, the untreated feathers could become pollutants because of their resistance to protease degradation. Feathers are rich in amino acids, which makes them a valuable source for fertilizer and animal feeds. Numerous bacteria and fungi exhibited capabilities to degrade chicken feathers by secreting enzymes such as keratinases, and accumulated evidence shows that feather-containing wastes can be converted into value-added products. This review summarizes recent progress in microbial degradation of feathers, structures of keratinases, feather application, and microorganisms that are able to secrete keratinase. In addition, the enzymes critical for keratin degradation and their mechanism of action are discussed. We also proposed the strategy that can be utilized for feather degradation. Based on the accumulated studies, microbial degradation of feathers has great potential to convert them into various products such as biofertilizer and animal feeds.
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Affiliation(s)
- Qingxin Li
- Guangdong Bioengineering Institute (Guangzhou Sugarcane Industry Research Institute), Guangdong Academy of Sciences, Guangzhou, China
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49
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Kang E, Jin HS, La JW, Sung JY, Park SY, Kim WC, Lee DW. Identification of keratinases from Fervidobacterium islandicum AW-1 using dynamic gene expression profiling. Microb Biotechnol 2019; 13:442-457. [PMID: 31613061 PMCID: PMC7017815 DOI: 10.1111/1751-7915.13493] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Revised: 09/17/2019] [Accepted: 09/18/2019] [Indexed: 01/11/2023] Open
Abstract
Keratin degradation is of great interest for converting agro‐industrial waste into bioactive peptides and is directly relevant for understanding the pathogenesis of superficial infections caused by dermatophytes. However, the mechanism of this process remains unclear. Here, we obtained the complete genome sequence of a feather‐degrading, extremely thermophilic bacterium, Fervidobacterium islandicum AW‐1 and performed bioinformatics‐based functional annotation. Reverse transcription PCR revealed that 57 putative protease‐encoding genes were differentially expressed in substrate‐dependent manners. Consequently, 16 candidate genes were highly expressed under starvation conditions, when keratin degradation begun. Subsequently, the dynamic expression profiles of these 16 selected genes in response to feathers, as determined via quantitative real‐time PCR, suggested that they included four metalloproteases and two peptidases including an ATP‐dependent serine protease, all of which might act as key players in feather decomposition. Furthermore, in vitro keratinolytic assays supported the notion that recombinant enzymes enhanced the decomposition of feathers in the presence of cell extracts. Therefore, our genome‐based systematic and dynamic expression profiling demonstrated that these identified metalloproteases together with two additional peptidases might be primarily associated with the decomposition of native feathers, suggesting that keratin degradation can be achieved via non‐canonical catalysis of several membrane‐associated metalloproteases in cooperation with cytosolic proteases.
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Affiliation(s)
- Eunju Kang
- School of Applied Biosciences, Kyungpook National University, Daegu, 41566, South Korea
| | - Hyeon-Su Jin
- Department of Biotechnology, Yonsei University, Seoul, 03722, South Korea
| | - Jae Won La
- Department of Biotechnology, Yonsei University, Seoul, 03722, South Korea
| | - Jae-Yoon Sung
- Department of Biotechnology, Yonsei University, Seoul, 03722, South Korea
| | - Soo-Young Park
- Department of Biotechnology, Yonsei University, Seoul, 03722, South Korea
| | - Won-Chan Kim
- School of Applied Biosciences, Kyungpook National University, Daegu, 41566, South Korea
| | - Dong-Woo Lee
- Department of Biotechnology, Yonsei University, Seoul, 03722, South Korea
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50
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Enzymatic bioconversion of feather waste with keratinases of Bacillus cereus PCM 2849. POLISH JOURNAL OF CHEMICAL TECHNOLOGY 2019. [DOI: 10.2478/pjct-2019-0030] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Abstract
Enzymatic preparation from culture of keratinolytic Bacillus cereus PCM 2849 was applied for hydrolysis of whole chicken feathers, after sulphitolytic pretreatment. This process was optimized using a three-factor Box-Behnken design, where the effect of substrate concentration, sulphite concentration during pretreatment and reaction temperature was evaluated on the release of amino acids. Obtained results revealed the highest impact of reaction temperature, followed by substrate content and sulphite during pretreatment. Optimal process conditions were established, i.e. temperature 44.4°C, feathers 4.7% and treatment with 25.3 mM sulphite. Amino acid composition of the obtained hydrolysate was analyzed. Glutamic acid (9.21 g·kg−1) and proline were dominant, however significant amount of branched-chain amino acids was also observed. The FTIR analysis of residual substrate revealed the cleavage of disulphide bonds in keratin through the presence of thioester residues. The absence of reduced cysteine residues was confirmed, along with minor changes in proportions of keratin substructures.
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