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Choudhary N, Dhingra N, Gacem A, Yadav VK, Verma RK, Choudhary M, Bhardwaj U, Chundawat RS, Alqahtani MS, Gaur RK, Eltayeb LB, Al Abdulmonem W, Jeon BH. Towards further understanding the applications of endophytes: enriched source of bioactive compounds and bio factories for nanoparticles. FRONTIERS IN PLANT SCIENCE 2023; 14:1193573. [PMID: 37492778 PMCID: PMC10364642 DOI: 10.3389/fpls.2023.1193573] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/25/2023] [Accepted: 05/31/2023] [Indexed: 07/27/2023]
Abstract
The most significant issues that humans face today include a growing population, an altering climate, an growing reliance on pesticides, the appearance of novel infectious agents, and an accumulation of industrial waste. The production of agricultural goods has also been subject to a great number of significant shifts, often known as agricultural revolutions, which have been influenced by the progression of civilization, technology, and general human advancement. Sustainable measures that can be applied in agriculture, the environment, medicine, and industry are needed to lessen the harmful effects of the aforementioned problems. Endophytes, which might be bacterial or fungal, could be a successful solution. They protect plants and promote growth by producing phytohormones and by providing biotic and abiotic stress tolerance. Endophytes produce the diverse type of bioactive compounds such as alkaloids, saponins, flavonoids, tannins, terpenoids, quinones, chinones, phenolic acids etc. and are known for various therapeutic advantages such as anticancer, antitumor, antidiabetic, antifungal, antiviral, antimicrobial, antimalarial, antioxidant activity. Proteases, pectinases, amylases, cellulases, xylanases, laccases, lipases, and other types of enzymes that are vital for many different industries can also be produced by endophytes. Due to the presence of all these bioactive compounds in endophytes, they have preferred sources for the green synthesis of nanoparticles. This review aims to comprehend the contributions and uses of endophytes in agriculture, medicinal, industrial sectors and bio-nanotechnology with their mechanism of action.
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Affiliation(s)
- Nisha Choudhary
- Dept of Biosciences, School of Liberal Arts and Sciences, Mody University of Science and Technology, Lakshmangarh, Sikar, Rajasthan, India
| | - Naveen Dhingra
- Department of Agriculture, Medi-Caps University, Pigdamber Road, Rau, Indore, Madhya Pradesh, India
| | - Amel Gacem
- Department of Physics, Faculty of Sciences, University 20 Août 1955, Skikda, Algeria
| | - Virendra Kumar Yadav
- Dept of Biosciences, School of Liberal Arts and Sciences, Mody University of Science and Technology, Lakshmangarh, Sikar, Rajasthan, India
- Department of Life Sciences, Hemchandracharya North Gujarat University, Patan, Gujarat, India
| | - Rakesh Kumar Verma
- Dept of Biosciences, School of Liberal Arts and Sciences, Mody University of Science and Technology, Lakshmangarh, Sikar, Rajasthan, India
| | - Mahima Choudhary
- Dept of Biosciences, School of Liberal Arts and Sciences, Mody University of Science and Technology, Lakshmangarh, Sikar, Rajasthan, India
| | - Uma Bhardwaj
- Department of Biotechnology, Noida International University, Noida, U.P., India
| | - Rajendra Singh Chundawat
- Dept of Biosciences, School of Liberal Arts and Sciences, Mody University of Science and Technology, Lakshmangarh, Sikar, Rajasthan, India
| | - Mohammed S. Alqahtani
- Radiological Sciences Department, College of Applied Medical Sciences, King Khalid University, Abha, Saudi Arabia
- BioImaging Unit, Space Research Centre, University of Leicester, Leicester, United Kingdom
| | - Rajarshi Kumar Gaur
- Department of Biotechnology, Deen Dayal Upadhyaya (D.D.U.) Gorakhpur University, Gorakhpur, Uttar Pradesh, India
| | - Lienda Bashier Eltayeb
- Department of Medical Laboratory Sciences, College of Applied Medical Sciences, Prince Sattam Bin AbdulAziz University- Al-Kharj, Riyadh, Saudi Arabia
| | - Waleed Al Abdulmonem
- Department of Pathology, College of Medicine, Qassim University, Buraidah, Saudi Arabia
| | - Byong-Hun Jeon
- Department of Earth Resources and Environmental Engineering, Hanyang University, Seoul, Republic of Korea
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Akram F, Aqeel A, Shoaib M, Haq IU, Shah FI. Multifarious revolutionary aspects of microbial keratinases: an efficient green technology for future generation with prospective applications. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:86913-86932. [PMID: 36271998 DOI: 10.1007/s11356-022-23638-w] [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: 05/14/2022] [Accepted: 10/10/2022] [Indexed: 06/16/2023]
Abstract
Since the dawn of century, tons of keratin bio-waste is generated by the poultry industry annually, and they end up causing environmental havoc. Keratins are highly flexible fibrous proteins which exist in α- and β- forms and provide mechanical strength and stability to structural appendages. The finding of broad-spectrum protease, keratinase, from thermophilic bacteria and fungi, has provided an eco-friendly solution to hydrolyze the peptide bonds in highly recalcitrant keratinous substances such as nails, feathers, claws, and horns into valuable amino acids. Microorganisms produce these proteolytic enzymes by techniques of solid-state and submerged fermentation. However, solid-state fermentation is considered as a yielding approach for the production of thermostable keratinases. This review prioritized the molecular and biochemical properties of microbial keratinases, and the role of keratinases in bringing prodigious impact for the sustainable progress of the economy. It also emphasizes on the current development in keratinase production with the focus to improve the biochemical properties related to enzyme's catalytic activity and stability, and production of mutant and cloned microbial strains to improve the yield of keratinases. Recently, multitude molecular approaches have been employed to enhance enzyme's productivity, activity, and thermostability which makes them suitable for pharmaceutical industry and for the production of animal feed, organic fertilizers, biogas, clearing of animal hides, and detergent formulation. Hence, it can be surmised that microbial keratinolytic enzymes are the conceivable candidates for numerous commercial and industrial applications.
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Affiliation(s)
- Fatima Akram
- Institute of Industrial Biotechnology, Government College University, Lahore, 54000, Pakistan.
| | - Amna Aqeel
- Institute of Industrial Biotechnology, Government College University, Lahore, 54000, Pakistan
| | - Minahil Shoaib
- Institute of Industrial Biotechnology, Government College University, Lahore, 54000, Pakistan
| | - Ikram Ul Haq
- Institute of Industrial Biotechnology, Government College University, Lahore, 54000, Pakistan
- Pakistan Academy of Science, Islamabad, Pakistan
| | - Fatima Iftikhar Shah
- Institute of Industrial Biotechnology, Government College University, Lahore, 54000, Pakistan
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Timorshina S, Popova E, Kreyer V, Baranova N, Osmolovskiy A. Keratinolytic Properties of Aspergillus clavatus Promising for Biodegradation. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:13939. [PMID: 36360819 PMCID: PMC9655890 DOI: 10.3390/ijerph192113939] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/06/2022] [Revised: 10/22/2022] [Accepted: 10/24/2022] [Indexed: 06/16/2023]
Abstract
The high demand for keratinolytic enzymes and the modest presentation of fungal keratinase diversity studies in scientific sources cause a significant interest in identifying new fungal strains of keratinase producers, isolating new enzymes and studying their properties. Four out of the 32 cultures showed a promising target activity on protein-containing agar plates-Aspergillus amstelodami A6, A. clavatus VKPM F-1593, A. ochraceus 247, and Cladosporium sphaerospermum 1779. The highest values of keratinolytic activity were demonstrated by extracellular proteins synthesized by Aspergillus clavatus VKPM F-1593 cultivated under submerged conditions on a medium containing milled chicken feathers. The enzyme complex preparation was obtained by protein precipitation from the culture liquid with ammonium sulfate, subsequent dialysis, and lyophilization. The fraction of a pure enzyme with keratinolytic activity (pI 9.3) was isolated by separating the extracellular proteins of A. clavatus VKPM F-1593 via isoelectric focusing. The studied keratinase was an alkaline subtilisin-like non-glycosylated protease active over a wide pH range with optimum keratinolysis at pH 8 and 50 °C.
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Protease Produced by Endophytic Fungi: A Systematic Review. Molecules 2021; 26:molecules26227062. [PMID: 34834154 PMCID: PMC8623497 DOI: 10.3390/molecules26227062] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2021] [Revised: 11/05/2021] [Accepted: 11/08/2021] [Indexed: 11/29/2022] Open
Abstract
The purpose of this systematic review was to identify the available literature of production, purification, and characterization of proteases by endophytic fungi. There are few complete studies that entirely exhibit the production, characterization, and purification of proteases from endophytic fungi. This study followed the PRISMA, and the search was conducted on five databases: PubMed, PMC, Science Direct, Scopus Articles, and Web of Science up until 18 May 2021, with no time or language restrictions. The methodology of the selected studies was evaluated using GRADE. Protease production, optimization, purification, and characterization were the main evaluated outcomes. Of the 5540 initially gathered studies, 15 met the inclusion criteria after a two-step selection process. Only two studies optimized the protease production using statistical design and two reported enzyme purification and characterization. The genus Penicillium and Aspergillus were the most cited among the eleven different genera of endophytic fungi evaluated in the selected articles. Six studies proved the ability of some endophytic fungi to produce fibrinolytic proteases, demonstrating that endophytic fungi can be exploited for the further production of agents used in thrombolytic therapy. However, further characterization and physicochemical studies are required to evaluate the real potential of endophytic fungi as sources of industrial enzymes.
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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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Biodegradation of Keratin-Rich Husbandry Waste as a Path to Sustainable Agriculture. SUSTAINABILITY 2021. [DOI: 10.3390/su13168691] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Every year, the size of the human population grows; with it, the need for agricultural products increases. This leads to an increment in the volume of waste, including hard-to-degrade keratin-rich ones, such as feathers. Currently, most of the agro-industrial complex protein by-products are utilized by incineration, landfilling, and chemical hydrolysis. Such methods do not meet modern trends in the development of a sustainable economy, negatively affecting the environment and humans, and preventing the reusing of waste. An alternative is biodegradation, which consists of the application of living organisms and their enzymes to recycle by-products. This approach is not only sustainable, but also makes it possible to obtain products of waste hydrolysis that are in demand for the manufacture of fertilizers and feed additives. This brings the development of agriculture closer to a circular economy and makes the recycling process more profitable. This review article emphasizes the significance of keratinolytic microorganisms and keratinases for the improvement of green methods for processing hard-to-degrade protein waste of the agro-industrial complex, which is necessary for sustainable economic development.
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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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El-Bondkly EAM, El-Bondkly AAM, El-Bondkly AAM. Marine endophytic fungal metabolites: A whole new world of pharmaceutical therapy exploration. Heliyon 2021; 7:e06362. [PMID: 33869822 PMCID: PMC8035529 DOI: 10.1016/j.heliyon.2021.e06362] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Revised: 04/16/2020] [Accepted: 02/22/2021] [Indexed: 12/19/2022] Open
Abstract
The growing threat arises due to diseases such as cancer and the infections around the world leading to a critical requirement for novel and constructive compounds with unique ways of action capable of combating these deadly diseases. At present, it is evident that endophytic fungi constitute an enormous as well as comparatively untapped source of great biodiversity that can be considered as a wellspring of effective novel natural products for medical, agricultural and industrial use. Marine endophytic fungi have been found in every marine plants (algae, seagrass, driftwood, mangrove plants), marine vertebrates (mainly, fish) or marine invertebrates (mainly, sponge and coral) inter- and intra-cellular without causing any palpable symptoms of illness. Since evolution of microbes and eukaryotes to a higher level, coevolution has resulted in specific interaction mechanisms. Endophytic fungi are known to influence the life cycle and are necessary for the homeostasis of their eukaryotic hosts and the chemical signals of their host have been shown to activate gene expression in endophytes to induce expression of endophytic secondary metabolites. Marine endophytic fungi are receiving increasing attention by chemists because of their varied and structurally unmatched compounds that have strong biological roles in life as lead pharmaceutical compounds, including anticancer, antiviral, insulin mimetic, antineurodegenerative, antimicrobial, antioxidant and immuno-suppressant compounds. Moreover, fungal endophytes proved to have different biological activities for exploitation in the environmental and agricultural sustainability.
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Production, purification, characterization, antioxidant and antiproliferative activities of extracellular L-asparaginase produced by Fusarium equiseti AHMF4. Saudi J Biol Sci 2021; 28:2540-2548. [PMID: 33911966 PMCID: PMC8071902 DOI: 10.1016/j.sjbs.2021.01.058] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2019] [Revised: 11/18/2020] [Accepted: 01/25/2021] [Indexed: 12/03/2022] Open
Abstract
L-Asparaginase is an antileukemic agent that depletes L-asparagine “an important nutrient for cancer cells” through the hydrolysis of L-asparagine into L-aspartic acid and ammonia leading to leukemia cell starvation and apoptosis in susceptible leukemic cell populations. Moreover currently, bacterial L-asparaginase has been limited by problems of lower productivity, stability, selectivity and a number of toxicities along with the resistance towards bacterial L-asparaginase. Then the current work aimed to provide pure L-asparaginase with in-vitro efficacy against various human carcinomas without adverse effects related to current L-asparaginase formulations. Submerged fermentation (SMF) bioprocess was applied and improved to maximize L-asparaginase production from Fusarium equiseti AHMF4 as alternative sources of bacteria. The enzyme production in SMF was maximized to reach 40.78 U mL−1 at the 7th day of fermentation with initial pH 7.0, incubation temperature 30 °C, 1.0% glucose as carbon source, 0.2% asparagine as nitrogen source, 0.1% alanine as amino acid supplement and 0.1% KH2PO4. The purification of AHMF4 L-asparaginase yielded 2.67-fold purification and 48% recovery with final specific activity of 488.1 U mg−1 of protein. Purified L-asparaginase was characterized as serine protease enzyme with molecular weight of 45.7 kDa beside stability at neutral pH and between 20 and 40 °C. Interestingly, purified L-asparaginase showed promising DPPH radical scavenging activity (IC50 69.12 μg mL−1) and anti-proliferative activity against cervical epitheloid carcinoma (Hela), epidermoid larynx carcinoma (Hep-2), hepatocellular carcinoma (HepG-2), Colorectal carcinoma (HCT-116), and breast adenocarcinoma (MCF-7) with IC50 equal to 2.0, 5.0, 12.40, 8.26 and 22.8 μg mL−1, respectively. The enzyme showed higher activity, selectivity and anti-proliferative activity against cancerous cells along with tiny cytotoxicity toward normal cells (WI-38) which indicates that it has selective toxicity and it could be applied as a less toxic alternative to the current formulations.
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Abdel-Azeem AM, Abo Nahas HH, Abdel-Azeem MA, Tariq FJ, Yadav AN. Biodiversity and Ecological Perspective of Industrially Important Fungi An Introduction. Fungal Biol 2021. [DOI: 10.1007/978-3-030-67561-5_1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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Mohamed El-Bondkly AA, El-Gendy MMAA, El-Bondkly EA, Ahmed AM. Biodiversity and biological activity of the fungal microbiota derived from the medicinal plants Salvia aegyptiaca L. and Balanties aegyptiaca L. BIOCATALYSIS AND AGRICULTURAL BIOTECHNOLOGY 2020. [DOI: 10.1016/j.bcab.2020.101720] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Citrobacter diversus-derived keratinases and their potential application as detergent-compatible cloth-cleaning agents. Braz J Microbiol 2020; 51:969-977. [PMID: 32291739 DOI: 10.1007/s42770-020-00268-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Accepted: 03/25/2020] [Indexed: 12/12/2022] Open
Abstract
Currently, poultry farming is one of the sectors that have a significant impact on the global economy. In recent years, there has been an increase in the production of broilers, inflicting this segment of the industry to generate tons of keratin due to huge disposal of chicken feathers. This points to the need to degrade these chicken feathers, as they have emerged as a major threat to the environment. Thus, in this study we aimed to identify keratinases that are produced by the bacterium Citrobacter diversus and further investigate the biochemical characteristics of these keratin-degrading enzymes. In a submerged medium, the bacterium was capable of degrading chicken feathers almost completely after 36 h of fermentation. We found a maximum caseinolytic activity at pH 9-10.5 and 50-55 °C, and keratinolytic activity at pH 8.5-9.5 and 50 °C. Thus, given its stability at higher temperatures, upon incubation of this enzyme extract for 1 h at 50 °C, it showed approximately 50% of the keratinolytic and 100% of the caseinolytic activity. Further, under pH stability for 48 h at 4 °C, the enzyme extract maintained greater residual activity in the pH range 6-8. Caseinolytic activity was inhibited by EDTA and PMSF, whereas the keratinolytic activity was inhibited only by EDTA. Additionally, due to its alkaline activity and detergent compatibility, this enzyme extract could improve washing performance when added to a commercial detergent formulation. Using application tests, we could demonstrate a potential use of this bacterial enzyme extract as an additive in detergents to remove egg stains from cloth.
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Adelere IA, Lateef A. Degradation of Keratin Biomass by Different Microorganisms. KERATIN AS A PROTEIN BIOPOLYMER 2019. [DOI: 10.1007/978-3-030-02901-2_5] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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Keratinolytic activity of Bacillus subtilis LFB-FIOCRUZ 1266 enhanced by whole-cell mutagenesis. 3 Biotech 2019; 9:2. [PMID: 30555768 DOI: 10.1007/s13205-018-1527-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2018] [Accepted: 12/03/2018] [Indexed: 02/06/2023] Open
Abstract
Discarded feathers represent an important residue from the poultry industry and are a rich source of keratin. Bacillus subtilis LFB-FIOCRUZ 1266, previously isolated from industrial poultry wastes, was used in this work and, through random mutation using ethyl methanesulfonate, ten strains were selected based on the size of their degradation halos. The feather degradation was increased to 115% and all selected mutants showed 1.4- to 2.4-fold increase in keratinolytic activity compared to their wild-type counterparts. The protein concentrations in the culture supernatants increased approximately 2.5 times, as a result of feather degradation. The mutants produced more sulfide than the wild-type bacteria that produced 0.45 µg/ml, while mutant D8 produced 1.45 µg/ml. The best pH for enzyme production and feather degradation was pH 8. Zymography showed differences in the intensity and molecular mass of some bands. The peptidase activity of the enzyme blend was predominantly inhibited by PMSF and EDTA, suggesting the presence of serine peptidases. HPTLC analysis evidenced few differences in band intensities of the amino acid profiles produced by the mutant peptidase activities. The mutants showed an increase in keratinolytic and peptidase activities, demonstrating their biotechnological potential to recycle feather and help to reduce the environmental impact.
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Microbial production and industrial applications of keratinases: an overview. Int Microbiol 2018; 21:163-174. [DOI: 10.1007/s10123-018-0022-1] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2018] [Revised: 07/05/2018] [Accepted: 07/06/2018] [Indexed: 11/25/2022]
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Călin M, Constantinescu-Aruxandei D, Alexandrescu E, Răut I, Doni MB, Arsene ML, Oancea F, Jecu L, Lazăr V. Degradation of keratin substrates by keratinolytic fungi. ELECTRON J BIOTECHN 2017. [DOI: 10.1016/j.ejbt.2017.05.007] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
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Batista-García RA, Sutton T, Jackson SA, Tovar-Herrera OE, Balcázar-López E, Sánchez-Carbente MDR, Sánchez-Reyes A, Dobson ADW, Folch-Mallol JL. Characterization of lignocellulolytic activities from fungi isolated from the deep-sea sponge Stelletta normani. PLoS One 2017; 12:e0173750. [PMID: 28339473 PMCID: PMC5365110 DOI: 10.1371/journal.pone.0173750] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2015] [Accepted: 02/24/2017] [Indexed: 12/03/2022] Open
Abstract
Extreme habitats have usually been regarded as a source of microorganisms that possess robust proteins that help enable them to survive in such harsh conditions. The deep sea can be considered an extreme habitat due to low temperatures (<5°C) and high pressure, however marine sponges survive in these habitats. While bacteria derived from deep-sea marine sponges have been studied, much less information is available on fungal biodiversity associated with these sponges. Following screening of fourteen fungi isolated from the deep-sea sponge Stelletta normani sampled at a depth of 751 metres, three halotolerant strains (TS2, TS11 and TS12) were identified which displayed high CMCase and xylanase activities. Molecular based taxonomic approaches identified these strains as Cadophora sp. TS2, Emericellopsis sp. TS11 and Pseudogymnoascus sp. TS 12. These three fungi displayed psychrotolerance and halotolerant growth on CMC and xylan as sole carbon sources, with optimal growth rates at 20°C. They produced CMCase and xylanase activities, which displayed optimal temperature and pH values of between 50-70°C and pH 5-8 respectively, together with good thermostability and halotolerance. In solid-state fermentations TS2, TS11 and TS12 produced CMCases, xylanases and peroxidase/phenol oxidases when grown on corn stover and wheat straw. This is the first time that CMCase, xylanase and peroxidase/phenol oxidase activities have been reported in these three fungal genera isolated from a marine sponge. Given the biochemical characteristics of these ligninolytic enzymes it is likely that they may prove useful in future biomass conversion strategies involving lignocellulosic materials.
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Affiliation(s)
- Ramón Alberto Batista-García
- Centro de Investigación en Dinámica Celular, Universidad Autónoma del Estado de Morelos, Cuernavaca, Morelos, Mexico
- Centro de Investigación en Biotecnología, Universidad Autónoma del Estado de Morelos, Cuernavaca, Morelos, Mexico
| | - Thomas Sutton
- School of Microbiology, University College Cork, Cork, Ireland
| | - Stephen A. Jackson
- School of Microbiology, University College Cork, Cork, Ireland
- Marine Biotechnology Centre, Environmental Research Institute, University College Cork, Cork, Ireland
| | - Omar Eduardo Tovar-Herrera
- Instituto de Biotecnología, Facultad de Ciencias Biológicas, Universidad Autónoma de Nuevo León, San Nicolás de los Garza, Nuevo León, Mexico
| | - Edgar Balcázar-López
- Centro de Investigación en Dinámica Celular, Universidad Autónoma del Estado de Morelos, Cuernavaca, Morelos, Mexico
- Centro de Investigación en Biotecnología, Universidad Autónoma del Estado de Morelos, Cuernavaca, Morelos, Mexico
| | | | - Ayixon Sánchez-Reyes
- Centro de Investigación en Dinámica Celular, Universidad Autónoma del Estado de Morelos, Cuernavaca, Morelos, Mexico
- Centro de Investigación en Biotecnología, Universidad Autónoma del Estado de Morelos, Cuernavaca, Morelos, Mexico
| | - Alan D. W. Dobson
- School of Microbiology, University College Cork, Cork, Ireland
- Marine Biotechnology Centre, Environmental Research Institute, University College Cork, Cork, Ireland
| | - Jorge Luis Folch-Mallol
- Centro de Investigación en Biotecnología, Universidad Autónoma del Estado de Morelos, Cuernavaca, Morelos, Mexico
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El-Gendy MMAA, Al-Zahrani SHM, El-Bondkly AMA. Construction of Potent Recombinant Strain Through Intergeneric Protoplast Fusion in Endophytic Fungi for Anticancerous Enzymes Production Using Rice Straw. Appl Biochem Biotechnol 2017; 183:30-50. [PMID: 28205049 DOI: 10.1007/s12010-017-2429-0] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2016] [Accepted: 01/25/2017] [Indexed: 11/30/2022]
Abstract
Among all fungal endophytes isolates derived from different ethno-medical plants, the hyper-yield L-asparaginase and L-glutaminase wild strains Trichoderma sp. Gen 9 and Cladosporium sp. Gen 20 using rice straw under solid-state fermentation (SSF) were selected. The selected strains were used as parents for the intergeneric protoplast fusion program to construct recombinant strain for prompt improvement production of these enzymes in one recombinant strain. Among 21 fusants obtained, the recombinant strain AYA 20-1, with 2.11-fold and 2.58-fold increase in L-asparaginase and L-glutaminase activities more than the parental isolates Trichoderma sp. Gen 9 and Cladosporium sp. Gen 20, respectively, was achieved using rice straw under SSF. Both therapeutic enzymes L-asparaginase and L-glutaminase were purified and characterized from the culture supernatant of the recombinant AYA 20-1 strain with molecular weights of 50.6 and 83.2 kDa, respectively. Both enzymes were not metalloenzymes. Whereas thiol group blocking reagents such as p-chloromercurybenzoate and iodoacetamide totally inhibited L-asparaginase activity, which refer to sulfhydryl groups and cysteine residues involved in its catalytic activity, they have no effect toward L-glutaminase activity. Interestingly, potent anticancer, antioxidant, and antimicrobial activities were detected for both enzymes.
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Affiliation(s)
- Mervat Morsy Abbas Ahmed El-Gendy
- Department of Biological Sciences, Faculty of Sciences, King Abdulaziz University (KAU), Jeddah, 21589, Saudi Arabia.,Chemistry of Natural and Microbial Products Department, National Research Centre, Dokki, Giza, 12622, Egypt
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Hamin Neto YAA, de Oliveira LCG, de Oliveira JR, Juliano MA, Juliano L, Arantes EC, Cabral H. Analysis of the Specificity and Biochemical Characterization of Metalloproteases Isolated from Eupenicillium javanicum Using Fluorescence Resonance Energy Transfer Peptides. Front Microbiol 2017; 7:2141. [PMID: 28119672 PMCID: PMC5220088 DOI: 10.3389/fmicb.2016.02141] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2016] [Accepted: 12/19/2016] [Indexed: 11/17/2022] Open
Abstract
Enzymes have important features that may facilitate their application in industrial processes and have been used as alternatives to chemical catalysts. In particular, proteases can be isolated from microorganisms, which provide important sources of advantageous enzymes for industrial processes. For example, Eupenicillium javanicum is a filamentous fungus that has been shown to express industrially applicable enzymes and chemical components, such as antifungal compounds. The biotechnological potential of E. javanicum and proteases made us search a novel protease from this microorganism. The macromolecule was isolated, the main biochemical properties was evaluated, and the specificity of the protease subsites was determined. The protease was produced under solid-state bioprocess with wheat bran and isolated by two chromatography steps with yield of 27.5% and 12.4-fold purification. The molecular mass was estimated at 30 kDa. The N-terminal sequence of the first 20 amino acid residues was AVGAGYNASVALALEKALNN. The enzyme presented higher proteolytic activity at pH 6.0 and 60°C. The protease is stable at wide range of pH values and temperatures and in the presence of surfactants. The “primed” side of the catalytic site showed the highest catalytic efficiency of the enzyme isolated from E. javanicum. The S′1 subsite is responsible for catalyzing the protease reaction with substrates with tyrosine in P′1. These findings provide important insights into the biochemical characterization of a highly active protease from E. javanicum and may facilitate the development of industrial processes involving this protease.
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Affiliation(s)
- Youssef A A Hamin Neto
- Department of Pharmaceutical Sciences, School of Pharmaceutical Sciences of Ribeirao Preto, University of São Paulo Ribeirão Preto, Brazil
| | - Lilian C G de Oliveira
- Department of Biophysics, Paulista Medical School, Federal University of São Paulo São Paulo, Brazil
| | - Juliana R de Oliveira
- Department of Biophysics, Paulista Medical School, Federal University of São Paulo São Paulo, Brazil
| | - Maria A Juliano
- Department of Biophysics, Paulista Medical School, Federal University of São Paulo São Paulo, Brazil
| | - Luiz Juliano
- Department of Biophysics, Paulista Medical School, Federal University of São Paulo São Paulo, Brazil
| | - Eliane C Arantes
- Department of Physics and Chemistry, School of Pharmaceutical Sciences of Ribeirao Preto, University of São Paulo Ribeirão Preto, Brazil
| | - Hamilton Cabral
- Department of Pharmaceutical Sciences, School of Pharmaceutical Sciences of Ribeirao Preto, University of São Paulo Ribeirão Preto, Brazil
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20
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Sahoo DK, Thatoi HN, Mitra B, Mondal KC, Das Mohapatra PK. Advances in Microbial Keratinase and Its Potential Applications. Microb Biotechnol 2017. [DOI: 10.1007/978-981-10-6847-8_5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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21
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Verma A, Singh H, Anwar S, Chattopadhyay A, Tiwari KK, Kaur S, Dhilon GS. Microbial keratinases: industrial enzymes with waste management potential. Crit Rev Biotechnol 2016; 37:476-491. [PMID: 27291252 DOI: 10.1080/07388551.2016.1185388] [Citation(s) in RCA: 66] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Proteases are ubiquitous enzymes that occur in various biological systems ranging from microorganisms to higher organisms. Microbial proteases are largely utilized in various established industrial processes. Despite their numerous industrial applications, they are not efficient in hydrolysis of recalcitrant, protein-rich keratinous wastes which result in environmental pollution and health hazards. This paved the way for the search of keratinolytic microorganisms having the ability to hydrolyze "hard to degrade" keratinous wastes. This new class of proteases is known as "keratinases". Due to their specificity, keratinases have an advantage over normal proteases and have replaced them in many industrial applications, such as nematicidal agents, nitrogenous fertilizer production from keratinous waste, animal feed and biofuel production. Keratinases have also replaced the normal proteases in the leather industry and detergent additive application due to their better performance. They have also been proved efficient in prion protein degradation. Above all, one of the major hurdles of enzyme industrial applications (cost effective production) can be achieved by using keratinous waste biomass, such as chicken feathers and hairs as fermentation substrate. Use of these low cost waste materials serves dual purposes: to reduce the fermentation cost for enzyme production as well as reducing the environmental waste load. The advent of keratinases has given new direction for waste management with industrial applications giving rise to green technology for sustainable development.
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Affiliation(s)
- Amit Verma
- a CBSH, SD Agricultural University , Gujarat , India
| | - Hukum Singh
- b Climate Change and Forest Influences Division , Forest Research Institute, ICFRE , Dehradun , India
| | - Shahbaz Anwar
- c Department of Microbiology , GBPUAT , Pantnagar , India
| | | | | | - Surinder Kaur
- e Department of Biological Sciences , University of Lethbridge , Lethbridge , AB , Canada.,f Lethbridge Research Centre, Agriculture and Agrifood Canada , Lethbridge , AB , Canada
| | - Gurpreet Singh Dhilon
- g Department of Food, Agricultural, and Nutritional Sciences , University of Alberta , Edmonton , AB , Canada
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22
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Bonugli-Santos RC, dos Santos Vasconcelos MR, Passarini MRZ, Vieira GAL, Lopes VCP, Mainardi PH, dos Santos JA, de Azevedo Duarte L, Otero IVR, da Silva Yoshida AM, Feitosa VA, Pessoa A, Sette LD. Marine-derived fungi: diversity of enzymes and biotechnological applications. Front Microbiol 2015; 6:269. [PMID: 25914680 PMCID: PMC4392690 DOI: 10.3389/fmicb.2015.00269] [Citation(s) in RCA: 86] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2014] [Accepted: 03/18/2015] [Indexed: 01/19/2023] Open
Abstract
The ocean is considered to be a great reservoir of biodiversity. Microbial communities in marine environments are ecologically relevant as intermediaries of energy, and play an important role in nutrient regeneration cycles as decomposers of dead and decaying organic matter. In this sense, marine-derived fungi can be considered as a source of enzymes of industrial and/or environmental interest. Fungal strains isolated from different substrates, such as invertebrates, decaying wood, seawater, sediments, and mangrove detritus, have been reported to be producers of hydrolytic and/or oxidative enzymes, with alginate lyase, amylase, cellulase, chitinase, glucosidase, inulinase, keratinase, ligninase, lipase, nuclease, phytase, protease, and xylanase being among the enzymes produced by fungi of marine origin. These enzymes present temperature and pH optima ranging from 35 to 70(∘)C, and 3.0 to 11.0, respectively. High-level production in bioreactors is mainly performed using submerged-state fermentation. Certain marine-derived fungal strains present enzymes with alkaline and cold-activity characteristics, and salinity is considered an important condition in screening and production processes. The adaptability of marine-derived fungi to oceanic conditions can be considered an attractive point in the field of fungal marine biotechnology. In this review, we focus on the advances in discovering enzymes from marine-derived fungi and their biotechnological relevance.
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Affiliation(s)
- Rafaella C. Bonugli-Santos
- Instituto Latino Americano de Ciências da Vida e da Natureza, Centro Interdisciplinar de Ciências da Vida, Universidade Federal da Integração Latino-AmericanaParaná, Brazil
| | - Maria R. dos Santos Vasconcelos
- Divisão de Recursos Microbianos, Centro Pluridisciplinar de Pesquisas Químicas, Biológicas e Agrícolas, Universidade Estadual de CampinasPaulínia, Brazil
| | - Michel R. Z. Passarini
- Divisão de Recursos Microbianos, Centro Pluridisciplinar de Pesquisas Químicas, Biológicas e Agrícolas, Universidade Estadual de CampinasPaulínia, Brazil
| | - Gabriela A. L. Vieira
- Laboratório de Micologia Ambiental e Industrial, Departamento de Bioquímica e Microbiologia, Instituto de Biociências, Universidade Estadual Paulista Júlio de Mesquita FilhoRio Claro, Brazil
| | - Viviane C. P. Lopes
- Laboratório de Micologia Ambiental e Industrial, Departamento de Bioquímica e Microbiologia, Instituto de Biociências, Universidade Estadual Paulista Júlio de Mesquita FilhoRio Claro, Brazil
| | - Pedro H. Mainardi
- Laboratório de Micologia Ambiental e Industrial, Departamento de Bioquímica e Microbiologia, Instituto de Biociências, Universidade Estadual Paulista Júlio de Mesquita FilhoRio Claro, Brazil
| | - Juliana A. dos Santos
- Laboratório de Micologia Ambiental e Industrial, Departamento de Bioquímica e Microbiologia, Instituto de Biociências, Universidade Estadual Paulista Júlio de Mesquita FilhoRio Claro, Brazil
| | - Lidia de Azevedo Duarte
- Laboratório de Micologia Ambiental e Industrial, Departamento de Bioquímica e Microbiologia, Instituto de Biociências, Universidade Estadual Paulista Júlio de Mesquita FilhoRio Claro, Brazil
| | - Igor V. R. Otero
- Laboratório de Micologia Ambiental e Industrial, Departamento de Bioquímica e Microbiologia, Instituto de Biociências, Universidade Estadual Paulista Júlio de Mesquita FilhoRio Claro, Brazil
| | - Aline M. da Silva Yoshida
- Laboratório de Micologia Ambiental e Industrial, Departamento de Bioquímica e Microbiologia, Instituto de Biociências, Universidade Estadual Paulista Júlio de Mesquita FilhoRio Claro, Brazil
| | - Valker A. Feitosa
- Departamento de Tecnologia Bioquímico-Farmacêutica, Faculdade de Ciências Farmacêuticas, Universidade de São PauloSão Paulo, Brazil
| | - Adalberto Pessoa
- Departamento de Tecnologia Bioquímico-Farmacêutica, Faculdade de Ciências Farmacêuticas, Universidade de São PauloSão Paulo, Brazil
| | - Lara D. Sette
- Divisão de Recursos Microbianos, Centro Pluridisciplinar de Pesquisas Químicas, Biológicas e Agrícolas, Universidade Estadual de CampinasPaulínia, Brazil
- Laboratório de Micologia Ambiental e Industrial, Departamento de Bioquímica e Microbiologia, Instituto de Biociências, Universidade Estadual Paulista Júlio de Mesquita FilhoRio Claro, Brazil
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Daroit DJ, Brandelli A. A current assessment on the production of bacterial keratinases. Crit Rev Biotechnol 2013; 34:372-84. [DOI: 10.3109/07388551.2013.794768] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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Anitha T, Palanivelu P. Purification and characterization of an extracellular keratinolytic protease from a new isolate of Aspergillus parasiticus. Protein Expr Purif 2013; 88:214-20. [DOI: 10.1016/j.pep.2013.01.007] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2012] [Revised: 12/07/2012] [Accepted: 01/02/2013] [Indexed: 10/27/2022]
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El-Bondkly AMA, El-Gendy MMA, Bassyouni RH. Overproduction and biological activity of prodigiosin-like pigments from recombinant fusant of endophytic marine Streptomyces species. Antonie van Leeuwenhoek 2012; 102:719-34. [PMID: 22777253 DOI: 10.1007/s10482-012-9772-5] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2012] [Accepted: 06/21/2012] [Indexed: 10/28/2022]
Abstract
Thirty-four endophytic marine Actinomycetes isolates were recovered from the Egyptian marine sponge Latrunculia corticata, out of them 5 isolates (14.7 %) showed red single colonies on yeast-CzAPEK plates. Isolates under the isolation code NRC50 and NRC51 were observed with the strongest red biomass. After application of protoplast fusion between NRC50 and NRC51 isolates, 26 fusants were selected and produced widely different amounts of prodigiosin-like pigments (PLPs) on different fermentation media. Among them fusant NRCF69 produced 79 and 160.4 % PLPs more than parental strains NRC50 and NRC51, respectively. According to the analysis of 16S rDNA sequence (amplified, sequenced, and submitted to GenBank under Accession no. JN232405 and JN232406, respectively), together with their morphological and biochemical characteristics, parental strains NRC50 (P1) and NRC51 (P2) were identified as Streptomyces sp. and designated as Streptomyces sp. NRC50 and Streptomyces sp. NRC51. This study describes a low cost, effective production media by using peanut seed broth, sunflower oil broth or dairy processing wastewater broth alone, or supplemented with 0.5 % mannitol that supports the production of PLPs by the Streptomyces fusant NRCF69 under study (42.03, 40.11, 36.7 and 47 g L(-1), respectively). PLPs compounds exhibited significant cytotoxic activities against three human cancer cell lines: colon cancer cell line (HCT-116), liver cancer cell line (HEPG-2) and breast cancer cell line (MCF-7) and antimycotic activity against clinical dermatophyte isolates of Trichophyton, Microsporum and Epidermophyton.
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Affiliation(s)
- Ahmed M A El-Bondkly
- Department of Genetics and Cytology, National Research Centre, Dokki, Giza, Egypt
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El-Bondkly AMA. Molecular identification using ITS sequences and genome shuffling to improve 2-deoxyglucose tolerance and xylanase activity of marine-derived fungus, Aspergillus sp. NRCF5. Appl Biochem Biotechnol 2012; 167:2160-73. [PMID: 22684364 DOI: 10.1007/s12010-012-9763-z] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2012] [Accepted: 05/30/2012] [Indexed: 11/28/2022]
Abstract
During the screening of xylanolytic enzyme from marine-derived fungi isolated from the inner tissue of Egyptian soft coral Rhytisma sp., one strain, NRCF5, exhibited high enzyme activity with 0.1 % (w/v) antimetabolite 2-deoxyglucose (2DG) tolerance. This fungal strain was identified as Aspergillus sp. NRCF5 based on its morphological characteristics and internal transcribed spacer (ITS) sequences. The ITS region of hyperactive xylanolytic strain (NRCF5) was amplified, sequenced, and submitted to GenBank (accession no. JQ277356). To apply the fundamental principles of genome shuffling in breeding of xylanase-producing fungi, marine-derived fungus Aspergillus sp. NRCF5 was used as starting strain in this work and applied for induction of genetic variability using different combinations and doses of mutagens. Five mutants with high xylanase activity and 0.25 % (w/v) antimetabolite 2DG tolerance were obtained from the populations generated by the mutation of combination between ultraviolet irradiation (UV, 5 min) and N-methyl-N-nitro-N-nitrosoguanidine (NTG, 100 μg/ml) for 30 (UNA) and 60 (UNB)min as well as NTG (100 μg/ml) and ethidium bromide (250 μg/ml) for 30 (NEA) and 60 (NEB)min. Then, they were subjected for recursive protoplast fusion. Seven hereditarily stable recombinants with high xylanase activity and 1.0 % (w/v) 2DG tolerance were obtained by four rounds of genome shuffling. Among them, a high xylanase-producing recombinant, R4/31, was obtained, which produced 427.5 U/ml xylanase. This value is 6.13-fold higher than that of the starting strain NRCF5 and 2.48-fold higher than that of the parent strain (mutant NEA51). The subculture experiments indicated that the high producer of marine Aspergillus sp. R4/31 fusant was stable.
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Cellulase production from agricultural residues by recombinant fusant strain of a fungal endophyte of the marine sponge Latrunculia corticata for production of ethanol. Antonie van Leeuwenhoek 2011; 101:331-46. [PMID: 21898149 DOI: 10.1007/s10482-011-9639-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2011] [Accepted: 08/23/2011] [Indexed: 10/17/2022]
Abstract
Several fungal endophytes of the Egyptian marine sponge Latrunculia corticata were isolated, including strains Trichoderma sp. Merv6, Penicillium sp. Merv2 and Aspergillus sp. Merv70. These fungi exhibited high cellulase activity using different lignocellulosic substrates in solid state fermentations (SSF). By applying mutagenesis and intergeneric protoplast fusion, we have obtained a recombinant strain (Tahrir-25) that overproduced cellulases (exo-β-1,4-glucanase, endo-β-1,4-glucanase and β-1,4-glucosidase) that facilitated complete cellulolysis of agricultural residues. The process parameters for cellulase production by strain Tahrir-25 were optimized in SSF. The highest cellulase recovery from fermentation slurries was achieved with 0.2% Tween 80 as leaching agent. Enzyme production was optimized under the following conditions: initial moisture content of 60% (v/w), inoculum size of 10(6) spores ml(-1), average substrate particle size of 1.0 mm, mixture of sugarcane bagasse and corncob (2:1) as the carbon source supplemented with carboxymethyl cellulose (CMC) and corn steep solids, fermentation time of 7 days, medium pH of 5.5 at 30°C. These optimized conditions yielded 450, 191, and 225 units/gram dry substrate (U gds(-1)) of carboxylmethyl cellulase, filter-paperase (FPase), and β-glucosidase, respectively. Subsequent fermentation by the yeast, Saccharomyces cerevisiae NRC2, using lignocellulose hydrolysates obtained from the optimized cellulase process produced the highest amount of ethanol (58 g l(-1)). This study has revealed the potential of exploiting marine fungi for cost-effective production of cellulases for second generation bioethanol processes.
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