Enzymes production from the edible mushroom.
Proteolytic enzymes are well known for catalyzing hydrolytic reactions. These enzymes fall under the group of large and complex, also known as proteases. Proteolytic enzymes mainly derived from microbial origin are favored because they have a short generation time, ease of genetic manipulation of microorganisms, and the availability of diverse species in nature. Macro fungi are significant and played an excellent role in degrading lignocellulosic compounds, such as mushrooms. They efficiently degrade cellulose and produce extracellular enzymes such as xylanases, cellulases, and ligninolytic enzymes. Furthermore, proteases play a significant role in fungi physiology, such as metalloproteinase, subtilases, aspartate, etc. Many worldwide researchers have reported the mycelial secretion of proteases from basidiomycetes. Thus, many protease extraction methods have been developed from the various categories of mushroom species, i.e., Pleurotusostreatus, Phanerochaetechrysosporium, Schizophyllum commune, Chondrostereumpurpureum, and Hypsizygusmarmoreus, etc. Furthermore, there is a high demand in the industry for specific proteolytic enzymatic activity. Numerous species of mushrooms have not been explored to date for the optimization and production of enzymes. Therefore, further detailed studies are required to expose the production mechanisms and application of proficient proteolytic enzymes from mushrooms. The present chapter will deliberately deal with proteolytic enzymes downstream processing and their various industrial applications.
- proteolytic enzymes
- macro fungi
- industrial application
Enzymes are natural catalysts that evolve or require various biological processes and are utilized in various industrial applications. Scientists have recently focused on detecting new enzymes with various properties and best-suited commercial purposes [1, 2]. There are many advantages associated with industrial enzymes, such as reaction specificity, low energy needs, biodegradable sources such as plants, animals, and microbes used for enzymes production and isolation. Proteases are the best studied and utilized in a group of enzymes that have the best substrate specificity. Total enzymes are produced at the industrial level, of which one-third are hydrolyses, and 65% are proteases. Proteases are hydrolytic enzymes that catalyze the interruption of the polymerization of protein. It evolves in the metabolic processes of biological activities in almost all organisms [3, 4, 5, 6].
Different microbial sources have produced different proteases than plants and animals; microbial enzymes are more labor-intensive and best suitable for industrial applications [3, 7, 8]. Approximately two-thirds of commercial protease is produced from microbial origin in the world . Microbial proteases production has advantages: short generation time, high growth rate, high yield, genetic modification is possible, cost-effective, and easy availability. These properties made microbial protease the best choice for biotechnological and industrial applications [9, 10].
Much research has been conducted to isolate and purify proteases from microbial sources and wieldy applied in industrial sectors [1, 11]. Bacteria are the most prominent microbes used for industrial-level protease production. Some groups of basidiomycetes also reported having proteases, and they provide the way for further study, fungal protease is neutral, acidic, or alkaline protease according to the species of fungi . Fungi proteases have easy cell separation techniques, and a study revealed that micromycetes proteases have specific characteristics. Several fungal species include Aspergillus species,
Basidiomycetes are important wood-degrading fungi in biological communities, and some genera of this group have been used as a food source. They are well studied for their extracellular enzymes production properties, such as xylanases, cellulases, and ligninolytic enzymes . Proteases play essential roles in the biochemical process in fungi and the essential completion of the life cycle . Mushrooms are the known Basidiomycetes in the fungi group. They have been used as food products for centuries as well as reported for their biological activity, among which, species of
Thus, the isolation of new
2. Classification of proteolytic enzymes or proteases
Proteolytic enzymes significantly participate in the metabolism of organisms such as plants, animals, bacteria, fungi, and viruses. Proteases are not explored and are essential in enzymology because of their substantial physiological significance and broad application in research activities . Since proteolytic enzymes are requisite in providing nitrogen to xylotrophs under natural growth conditions (on living and dead wood), the absence of sufficient systematic information on secreted proteases of higher xylotrophic fungi is unnoticeable yet in biology. Research studies have been conducted to isolate and characterize proteolytic enzymes from the cultured mycelium and fruit bodies of basidiomycetes. Highly diverse types of structures and mechanisms of action, so proteases are not set aside with the rules of enzyme nomenclature . So, the classification of these enzymes is often difficult. The enzyme that enters through the plasma membrane inside the cell is usually called an extracellular enzyme . It must be classified into two categories according to their ability to cleave the peptide bonds as exopeptidases and cleave specific sites of peptide bonds as endopeptidases. They are industrially essential enzymes . The diversity and specificity of these native enzymes are based on their broad characterization and isolation (Table 1). Based on active site present on proteases, they are classified as follows:
|S N||Mushroom||Enzyme/protease||Cultivation condition||Method of purification/isolation||References|
|1.||Laccase isoenzymes||Liquid culture||Polyacrylamide gel electrophoresis|||
|2.||Pleureryn||—||Ion exchange chromatography|||
|3.||Eryngeolysin||Fruiting body||Ion exchange chromatography|||
|4.||Fruiting bodies||Ion exchange chromatography|||
|5.||Fibrinolytic protease||Mycelia culture||SDS-PAGE|||
|7.||Metal-dependent proteinases||Fruiting body||Ion exchange chromatography|||
|8.||Nebrodeolysin||Fruiting body||Ion exchange and gel filtration chromatography|||
|11.||Serine protease||—||Ion exchange chromatography|||
|12.||Alkaline protease||—||Ion exchange chromatography|||
|13.||Fibrinolytic enzyme||Submerged culture fermentation||Ammonium sulfate precipitation, hydrophobic interaction, and gel filtration chromatographies|||
|14.||Alkaline protease||Solid state fermentation||—|||
|15.||Signal Peptide Peptidase||Liquid culture||Ammonium sulphateprecipitation, Ion-exchange chromatography, and HPLC|||
|16.||—||Solid-State Fermentation||Ammonium sulfate precipitation|||
Exopeptidases are an enzyme that cleaves at the end site and requires free terminal groups close to the bond. It catalyzes the breakdown of specific peptide bonds after the carboxyl or amino terminals in the protein. Based on their efficiency in identifying the active site as either C or N terminal, they are further divided as carboxypeptidases or amino peptidases .
Amino peptidases are the class of proteases enzymes that precisely cut at the N-terminal of the amino acid polypeptide chain, breaking it into dimer fragments or a single amino acid residue. After the recognition, they further remove the present methionine N-terminal of the polypeptide chain, which may differ in their expression. It is found in various microbial strains, including basidiomycetes fungi, molds, and bacteria, etc. Overall, amino peptidases work as intracellular enzymes; however, as per a report studied, amino peptidases that originated from
This enzyme performs its catalytic reaction on the C-terminal of the amino acid chain, breaking peptide bonds into monomers form. These are not predominantly recognized as endopeptidases because they leave few amino acid molecules at the target site of the protein. Instead, it can be employed to eliminate the additional tags at the carboxyl-terminal of the target protein. Among specific peptidases, metallocarboxy protease, type A carboxypeptidase, is known primarily for removing amino acid of the aromatic side chain while type B acts on essential amino acids .
Endopeptidases act at specific site of the peptide bond of the substrate . It cleaves the internal peptide bonds of proteins influenced by the existing functional group present on the active site of the peptide chain. It is further classified as follows:
2.2.1 Serine proteases
These classes of proteases are broadly found in nature and present in cellular organisms. Along with all the identified proteolytic enzymes, a significant part is of serine proteases. It generally performs the cleavage action on the bond present in the central part of the amino acid chain. However, few Serine proteases act as exopeptidases by detaching the amino acids from the end terminal of the polypeptide chain. Its name derives from the Ser residue present in the peptide chain, which is nucleophilic and placed in the active site of the chain of amino acids. An intermediate substrate is formed by using the serine residues inform of acyl-enzyme at the C end terminal of the newly structured peptide bond .
2.2.2 Cysteine/thiol proteases
This enzyme contains cysteine residues at their active site present both in prokaryotes and eukaryotes microbes. It shows proteolytic activity at the 6–8 pH range with 50–70°C optimum temperature. Hydrogen cyanide is the key component that activates this enzyme, resulting in which SH group is formed in a polypeptide chain. Oxidizing agents can inhibit this kind of proteases and show sensitive action to the sulfhydryl agents, for example, p-CMB .
Metalloproteases are generally zinc-containing enzymes. In fungi or basidiomycetes, several metal ions such as calcium, cobalt, and zincare are involved in their reactivation. Zinc-containing enzymes and calcium are essential for proteineous activity and structural stability of protein at optimum pH 5–9. These are sensitive to an agent that causes chelation of metal, such as ethylen diamine tetracetic acid (EDTA), but are insensitive to cysteine inhibitors .
2.2.4 Aspartic proteases
It is a comparatively small class of endopeptidases that includes aspartic proteases. These proteases are composed of a pair of aspartates bilobed structures, including a leading catalytic site. It functions optimally on acidic pH and is present in nature. This enzyme is secreted by various microorganisms such as bacteria and fungus, as their virulence secretions. Also, it can perform the mutualistic function in the breakdown of proteins yielding nitrogen from urea. These kinds of proteases are primarily biased toward the hydrophobic amino acids nearer to the dipeptides bond. As compared with the other two endoproteases, it utilizes residues present in the active site showing nucleophilic attribute for proteolysis .
3. Proteolytic enzymes from mushroom species
As proteolytic enzymes are indispensable in supplying nitrogen to xylotrophs under natural growth conditions (on living and dead wood), the absence of sufficient systematic information on secreted proteases of higher xylotrophic fungi is not much explored . The protein structure contains nitrogen, which is probably the reason for the secretion of extracellular proteolytic enzymes basidiomycetes or mushroom. The species belong to orders of basidial fungi,
4. Role of proteolytic enzymes in mushroom
Proteases perform complex physiological functions, including protein catabolism; blood clotting, cell growth and migration, morphogenesis, and development . Mushrooms or basidiomycetes fungi are heterotrophic organisms. They can utilize both organic and inorganic nitrogen sources as nutrition. An under natural conditions, they usually secrete various extracellular enzymes to decompose natural organic materials such as ligninolytic enzymes. Protease from mushrooms involves endopeptidases, and exopeptidases act one after another as the former produces many free C and N terminal ends and latter act on the peptide fragments, thus forming the decomposed protein. This broad specificity is a significant property of the fungal secreted proteases and other proteolytic enzymes employed to break down proteins. An investigation reported on fungus
5. Methods used for proteolytic enzymes recovery and production
6. Applications and future prospects
Novel investigation techniques revealed highly specific and selective protein modifications performed by proteases, including activating the zymogenic enzyme forms by limited proteolysis, forming hormones and other physiologically active peptides from precursor proteins, thrombus lysis, or the processing and transport of secreted proteins through the membrane (Figure 1). The vital role of proteolytic enzymes in metabolic and regulatory processes explains their occurrence in all living organisms .
6.1 In the detergent industry
Proteases were used as a detergent centuries ago as the “Burnus” brand, along with sodium carbonate and pancreatic extract mixed in it . Several industries, such as chemical, pharmaceutical, food processing, detergents, and leather processing, utilize the catalytic properties of proteases. Its application in the bioremediation of pollutants has also been reported. Several factors such as optimum substrate specificity, temperature, optimum pH, chemical stability, and catalytic activity may vary because of a diverse group and also can affect the production of proteases .
6.2 Cell-free enzyme preparation
Immense interest has been grown in proteases due to their thermal ability in a wide range of temperatures. It is also used as detergents in the cell separation process for the production of cell-free enzyme preparations. In these perspective, fungal enzymes have applications as these are extracellularly secreted [55, 56].
6.3 In the pharmaceutical and food industries
Some proteases are also found to produce due to the infection process caused by foreign invaders such as bacteria, fungus, and viruses. A variety of steps regulate the mechanism of proteolytic enzyme reactions, including substrate specificity, ATP-directed protein degradation, restricted access to the active site, highly specific protein modifications. It can activate zymogenic forms of enzymes by restricted proteolysis activity . Including these protease enzymes that cause diseases to host cells has become a good option for developing therapeutic agents for the diseases such as cancer, hepatitis, malaria, and candidiasis. It has also been reported to demonstrate potent immunomodulatory activity .
6.4 Leather industry
The leather industry involves various steps to obtain processed leather, for example, soaking, liming, hair removal, bating, deliming, and degreasing. These steps are applied using poisonous chemicals such as salt, lime, solvents, and sodium sulfide, resulting in pollution. The exclusion of non-collagenous particles is required in leather processing, which decides the softness and durability of leather products [58, 59]. It can be controlled by applying enzymes such as proteases in the place of chemicals .
Most of the industrial proteases used are of microbial origin, especially of bacteria. These enzymes are preferentially selected because of their desired characteristics and lower cost. The bioengineering manufacture of microbial proteases is favored as they have short generation periods, high yield, ease of genetic desired modification, and diverse species available. Future opportunities are high in cutting-edge research from the pharmaceutical perspective of the protease gene. By the help via recombinant DNA technology, respective genes must have been cloned and sequenced to determine the function of enzymes that cause changes in the attributes of protease enzymes and enhance enzyme production for their commercial usage. In industries, proteases contribute to the high value-added products development, and the same way biological catalysts offer advantages over the use of chemical catalysts for numerous reasons, such as high catalytic activity, high specificity, and their availability in economically viable quantities.
Conversely, cost associated with the production of proteases from mushrooms or basidiomycetes is the major obstacle to their application in industries and pharmaceuticals. For that reason, further research studies should have been implemented to discover novel low-cost proteases from mushrooms and their application in commercial and industrial sectors. So, a great extent of the study of proteases from the mushroom requires further investigations.
The authors are thankful to the Junior Research Fellowship (DBT/JRF/BET-18/I/2018/AL/123), Department of Biotechnology, Biotech Consortium of India Limited, and Pt. Ravishankar Shukla University Research scholarship award (797/Fin/Sch./2021) for providing funding support. The authors are also are thankful to the Head, School of Studies in Biotechnology, Pt. Ravishankar Shukla University, Raipur.
Conflict of interest
The authors declare no conflict of interest.
Inacio DF, Ferreira RO, CA VA, Brugnari T, Castoldi R, Peralta RM, et al. Proteases of wood rot fungi with emphasis on the genus Pleurotus. BioMed Research International. 2015; 2015:1-10
Daroit DJ, Correa APF, Brandelli A. Production of keratinolytic proteases through bioconversion of feather meal by the Amazonian bacterium Bacillussp. P45. International Biodeterioration and Biodegradation. 2011; 65:45-51
Rao CS, Sathish T, Ravichandra P, Prakasham R. Characterization of thermo-and detergent stable serine protease from isolated Bacillus circulansand evaluation of eco-friendly applications. Process Biochemistry. 2009; 44:262-268
Rao MB, Tanksale AM, Ghatge MS, Deshpande VV. Molecular and biotechnological aspects of microbial proteases. Microbiological Reviews. 1998; 62:597-635
Singhal P, Nigam V, Vidyarthi A. Studies on production, characterization and applications of microbial alkaline proteases. International Journal of Advanced Biotechnology and Research. 2012; 3:653-669
Beg QK, Gupta R. Purification and characterization of an oxidation-stable, thiol-dependent serine alkaline protease from Bacillus mojavensis. Enzyme and Microbial Technology. 2003; 32:294-304
Gupta R, Beg Q, Lorenz P. Bacterial alkaline proteases: Molecular approaches and industrial applications. Applied Microbiology and Biotechnology. 2002; 59:15-32
Kalaiarasi K, Sunitha P. Optimization of alkaline protease production from Pseudomonas fluorescensisolated from meat waste contaminated soil. African Journal of Biotechnology. 2009; 8:24
Nisha N, Divakaran J. Optimization of alkaline protease production from Bacillus subtilisNS isolated from sea water. African Journal of Biotechnology. 2014; 13(65):24
Ali N, Ullah N, Qasim M, Rahman H, Khan SN. Molecular characterization and growth optimization of halo-tolerant protease producing Bacillus subtilisstrain BLK-1.5 isolated from salt mines of Karak, Pakistan. Extremophiles. 2016; 20:395-402
Adrio J, Demain A. Microbial enzymes: Tools for biotechnological processes. Biomolecules. 2014; 4:117-139
Said D, Pietro RCLR. Enzimascomoagents Bio Tecnologicos. Ribeirao Preto, Brazil: Legis Summa; 2004
Kang SG, Kim IS, Rho YT, Lee KJ. Production dynamics of extracellular proteases accompanying morphological differentiation of Streptomyces albidoflavusSMF301. Microbiology. 1995; 141:3095-3103
Kudryavtseva OA, Dunaevsky YE, Kamzolkina OV, Belozersky MA. Fungal proteolytic enzymes: Features of the extracellular proteases of xylotrophic basidiomycetes. Microbiology. 2008; 77:643-653
Nakamura M, Iketani A, Shioi Y. A survey of proteases in edible mushrooms with synthetic peptides as substrates. Mycoscience. 2011; 52:234-241
Cui L, Liu QH, Wang HX, Ng TB. An alkaline protease from fresh fruiting bodies of the edible mushroom Pleurotus citrinopileatus. Applied Microbiology and Biotechnology. 2007; 75:81-85
Patel Y, Naraian R, Singh VK. Medicinal properties of Pleurotusspecies (oyster mushroom): A review. World Journal of Fungal and Plant Biology. 2012; 3:1-12
Wang H, Ng TB. Pleureryn, a novel protease from fresh fruiting bodies of the edible mushroom Pleurotus eryngii. Biochemical and Biophysical Research Communications. 2001; 289:750-755
Iandolo D, Piscitelli A, Sannia G, Faraco V. Enzyme production by solid substrate fermentation of Pleurotus ostreatusand Trametes versicoloron tomato pomace. Applied Biochemistry and Biotechnology. 2011; 163:40-51
AbdWahab NA, Abdullah N, Aminudin N. Characterisation of potential antidiabetic-related proteins from Pleurotus pulmonarius(Fr.) Quel. (grey oyster mushroom) by MALDITOF/TOF mass spectrometry. BioMed Research International. 2014; 2014:1-9
Sabotic J, Trcek T, Popovi T, Brzin T. Basidiomycetes harbour a hidden treasure of proteolytic diversity. Journal of Biotechnology. 2007; 128:297-307
Palmieri G, Giardina P, Bianco C, Fontanella B, Sannia G. Copper induction of laccase isoenzymes in the ligninolytic fungus Pleurotus ostreatus. Applied and Environmental Microbiology. 2000; 66:920-924
Ngai PHK, Ng TB. A hemolysin from the mushroom Pleurotus eryngii. Applied Microbiology and Biotechnology. 2006; 72:1185-1191
Shen MH, Kim JS, Sapkotaetal K. Purification, characterization, and cloning of fibrinolytic metalloprotease from Pleurotus ostreatusmycelia. Journal of Microbiology and Biotechnology. 2007; 17:1271-1283
Islam MM. Molecular cloning, expression and characterization of a serine proteinase from Japanese edible mushroom, Grifolafrondosa: Solving the structure–function anomaly of a reported aminopeptidase. Electronic Journal of Biotechnology. 2008; 11:1-12
Lebedeva GV, Proskuryakov MT. Purification andcharacterization of milk-clotting enzymes from oyster mushroom ( Pleurotus ostreatus(Fr.) Kumm). Applied Biochemistry and Microbiology. 2009; 45:623-625
Lv H, Kong Y, Yaoetal Q. Nebrodeolysin, a novel hemolytic protein from mushroom Pleurotus nebrodensiswith apoptosis inducing and anti-HIV-1effects. Phytomedicine. 2009; 16:98-205
Shibata T, Kudou M, Hoshi Y, Kudo A, Nanashima N, Miyairi K. Isolation and characterization of a novel two-component hemolysin, erylysin A and B, from an edible mushroom, Pleurotus eryngii. Toxicon. 2010; 56:1436-1442
Cha WS, Park SS, Kim SJ, Choi D. Biochemicaland enzymatic properties of a fibrinolytic enzyme from Pleurotus eryngiicultivated under solid-state conditions using corncob. Bioresource Technology. 2010; 101:6475-6481
Zhang G, Wang H, Zhang X, Ng T. Helvellisin, a novel alkaline protease from the wild ascomycete mushroom Helvella lacunosa. Journal of Bioscience and Bioengineering. 2010; 109:20-24
Zheng S, Wang H, Zhang G. A novel alkaline protease from wild edible mushroom Termitomyces albuminosus. Acta Biochimica Polonica. 2011; 58:269-273
Liu XL, Zheng XQ, Qian PZ. Purification and characterization of a novel fibrinolytic enzyme from culture supernatantof Pleurotus ostreatus. Journal of Microbiology and Biotechnology. 2014; 24:245-253
Machado ARG, Teixeira MFS, de Souza KL, Campelo MCL, de Aguiar Oliveira IM. Nutritional value and proteases of Lentinus citrinusproduced by solid state fermentation of lignocellulosic waste from tropical region. Saudi Journal of Biological Sciences. 2016; 23:621-627
Benmrad MO, Mechri S, Jaouadi NZ, Elhoul MB, Rekik H, Sayadi S, et al. Purification and biochemical characterization of a novel thermostable protease from the oyster mushroom Pleurotus sajor-cajustrain CTM10057 with industrial interest. BMC Biotechnology. 2019; 19:43
Ravikumar G, Gomathi D, Kalaiselvi M, Uma C. A protease from the medicinal mushroom Pleurotus sajor-caju; production, purification and partial characterization. Asian Pacific Journal of Tropical Biomedicine. 2012; 2:411-417
Sawant R, Nagendran S. Protease: An enzyme with multiple industrial applications. World Journal of Pharmacy and Pharmaceutical Sciences. 2014; 3:568-579
Motyan JA, Toth F, Tozser J. Research applications of proteolytic enzymes in molecular biology. Biomolecules. 2013; 3:923-942
Page M, Di Cera E. Serine peptidases: Classification, structure and function. Cell and Molecular Life Sciences. 2008; 65:1220-1236
Thakur N, Goyal M, Sharma S, Kumar D. Proteases: Industrial applications and approaches used in strain improvement. Biological Forum–An International Journal. 2018; 10:158-167
Ellaiah P, Srinivasulu B, Adinarayana K. A review on microbial alkaline proteases. Journal of Scientific and Industrial Research. 2002; 61:690-704
Turk B, Turk D, Turk V. Protease signalling: The cutting edge. The EMBO Journal. 2012; 31:1630-1643
Abraham L, Breuil C, Bradshaw ED, Morris PI, Byrne T. Proteinases As potential targets for new generation anti-Sapstain chemicals. Forest Products Journal. 1997; 47:57-63
Caporale C, Garzillo AMV, Caruso C, Buonocore V. Characterisation of extracellular proteases from Trametes trogii. Phytochemistry. 1996; 41:385-393
Joh JH, Kim BG, Kong WS, Yoo YB, Kim NK, Park HR, et al. Cloning and developmental expression of a metzincin family metalloprotease CDNA from oyster mushroom Pleurotus ostreatus. FEMS Microbiology Letters. 2004; 239:57-62
Barsukova TN, Garibova LV, Ivanov AI. Ecologo biological characterization of Pleurotus pulmonarius(Fr.) Quel. Mikologiya i Fitopatologiya. 1989; 23:14-19
Pandey A, Soccol CR, Mitchell D. New developments in solid state fermentation. I bioprocesses and products process. The Biochemist. 2000; 35:1153-1169
Singh AD, Abdullah N, Vikineswary S. Optimization of extraction of bulk enzymes from spent mushroom compost. Journal of Chemical Technology & Biotechnology. 2003; 78:743-752
Ko HG, Park SH, Kim SH, Park HG, Park WM. Detection and recovery of hydrolytic enzymes from spent compost of four mushroom species. Folia Microbiologica. 2005; 50:103-106
Mayolo-Deloisa K, Trejo-Hernández MDR, Rito-Palomares M. Recovery of laccase fromthe residual compost of Agaricusbisporusin aqueous two-phase systems. Process Biochemistry. 2009; 44:435-439
Chen S, Ge W, Buswell JA. Biochemical and molecular characterization of a laccase from the edible straw mushroom, Volvariellavolvacea. European Journal of Biochemistry. 2004; 271:318-328
Ullrich R, Huong LM, Dung NL, Hofrichter M. Laccase from the medicinal mushroom Agaricusblazei: Production, purification and characterization. Applied Microbiology and Biotechnology. 2005; 67:357-363
Quaratino D, Federici F, Petruccioli M, Fenice M, D'Annibale A. Production, purification and partial characterisation of a novel laccase from the white-rot fungus Panustigrinus CBS 577.79. Antonie Van Leeuwenhoek. 2007; 91:57-69
Sani JT, Gharibi SOS, Shariati MA. The importance of alkaline protease commercial applications: A short review. Indian Journal of Research in Pharmacy and Biotechnology. 2017; 5:534-538
Landolo D, Piscitelli A, Sannia G, Faraco V. Enzyme production by solid substrate fermentation of Pleurotus ostreatusand Trametes versicoloron tomato pomace. Applied Biochemistry and Biotechnology. 2011; 163:40-51
Sumantha A, Larroche C, Pandey A. Microbiology and industrial biotechnology of food-grade proteases: A perspective. Food Technology and Biotechnology. 2006; 44(2):211-220
Shaba AM, Baba J. Screening of Pleurotus ostreatusand Gleophylumsepiariumstrains for extracellular protease enzyme production. Bayero Journal of Pure and Applied Sciences. 2014; 5(1):187-190
Vandeputte-Rutten L, Gros P. Novel proteases: Common themes and surprising features. Current Opinion in Structural Biology. 2002; 12(6):704-708
Khan F. New microbial proteases in leather and detergent industries. Recent Innovations in Chemical Engineering. 2013; 1:1-6
Wahab WAA, Ahmed SA. Response surface methodology for production, characterization and application of solvent, salt and alkali-tolerant alkaline protease from isolated fungal strain aspergillus Niger WA.International Journal of Biological Macromolecules. 2017; 115:447-458
Sharma M, Gat Y, Arya S. A review on microbial alkaline protease: An essential tool for various industrial approaches. Industrial Biotechnology. 2019; 15:69-78