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Abdullah R, Tahseen M, Nisar K, Kaleem A, Iqtedar M, Saleem F, Aftab M. Statistical optimization of cellulases by Talaromyces thermophilus utilizing Saccharum spontaneum, a novel substrate. ELECTRON J BIOTECHN 2021. [DOI: 10.1016/j.ejbt.2021.03.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
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Shilova AV, Maksimov AY, Maksimova YG. Isolation and Identification of Alkalitolerant Bacteria with Hydrolytic Activity from a Soda Sludge Storage. Microbiology (Reading) 2021. [DOI: 10.1134/s0026261721020120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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Math RK, Kambiranda D, Yun HD, Ghebreiyessus Y. Binding of cloned Cel enzymes on clay minerals related to the pI of the enzymes and database survey of cellulases of soil bacteria for pI. Biosci Biotechnol Biochem 2019; 84:238-246. [PMID: 31625450 DOI: 10.1080/09168451.2019.1679613] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
The Cel genes from Bacillus licheniformis MSB03 were cloned and expressed to investigate binding ability on clay minerals and sea sand at pH ranging 3 to 9. FTIR analysis has been done to characterize bound enzymes on clay minerals. Subsequent, surveying of NCBI database for extracellular enzymes of soil bacteria was carried out. Among the five cloned Cel enzymes assayed for binding to clay minerals, only Cel5H enzyme had the binding ability. Enzyme Cel5H exhibited highest binding to montmorillonite followed by kaolinite and sea sand. Interestingly, Cel5H had higher pI value of 9.24 than other proteins (5.2-5.7). Cel5H binding to montmorillonite was shown to be negatively affected below pH 3 and above pH 9. Infrared absorption spectra of the Cel5H-montmorillonite complexes showed distinct peaks for clay minerals and bound proteins. Furthermore, database survey of soil bacterial extracellular enzymes revealed that Bacillus species enzymes had higher pI than other soil bacterial enzymes.
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Affiliation(s)
- Renukaradhya K Math
- Research Institute of Agriculture and Life Science, Gyeongsang National University, Chinju, Republic of Korea
| | - Devaiah Kambiranda
- Department of Agricultural Sciences, Southern University Agriculture Research and Extension Center, Baton Rouge, LA, USA
| | - Han Dae Yun
- Research Institute of Agriculture and Life Science, Gyeongsang National University, Chinju, Republic of Korea
| | - Yemane Ghebreiyessus
- Department of Agricultural Sciences, Southern University Agriculture Research and Extension Center, Baton Rouge, LA, USA
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Adsul M, Sandhu SK, Singhania RR, Gupta R, Puri SK, Mathur A. Designing a cellulolytic enzyme cocktail for the efficient and economical conversion of lignocellulosic biomass to biofuels. Enzyme Microb Technol 2019; 133:109442. [PMID: 31874688 DOI: 10.1016/j.enzmictec.2019.109442] [Citation(s) in RCA: 57] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2019] [Revised: 10/03/2019] [Accepted: 10/04/2019] [Indexed: 11/19/2022]
Abstract
Concerns about dwindling fossil fuels and their unfavorable environmental impacts shifted the global focus towards the development of biofuels from lignocellulosic feedstocks. The structure of this biomass is very complex due to which variety of enzymes (cellulolytic, hemicellulolytic, auxiliary/AA9) and proteins (e.g. swollenin) required for efficient deconstruction. Major impediments in large-scale commercial production of cellulosic ethanol are the cost of cellulases and inability of any single microorganism to produce all cellulolytic components in sufficient titers. In the recent past, various methods for reducing the enzyme cost during cellulosic ethanol production have been attempted. These include designing optimal synergistic enzyme blends/cocktail, having certain ratios of enzymes from different microbial sources, for efficient hydrolysis of pretreated biomass. However, the mechanisms underlying the development, strategies for production and evaluation of optimal cellulolytic cocktails still remain unclear. This article aims to explore the technical and economic benefits of using cellulolytic enzyme cocktail, basic enzymatic and non-enzymatic components required for its development and various strategies employed for efficient cellulolytic cocktail preparation. Consideration was also given to the ways of evaluation of commercially available and in-house developed cocktails. Discussion about commercially available cellulolytic cocktails, current challenges and possible avenues in the development of cellulolytic cocktails included.
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Affiliation(s)
- Mukund Adsul
- DBT-IOC Centre for Advanced Bioenergy Research, R & D Centre, Indian Oil Corporation Ltd, Sector-13, Faridabad 121007, India.
| | - Simranjeet Kaur Sandhu
- DBT-IOC Centre for Advanced Bioenergy Research, R & D Centre, Indian Oil Corporation Ltd, Sector-13, Faridabad 121007, India
| | - Reeta Rani Singhania
- DBT-IOC Centre for Advanced Bioenergy Research, R & D Centre, Indian Oil Corporation Ltd, Sector-13, Faridabad 121007, India
| | - Ravi Gupta
- DBT-IOC Centre for Advanced Bioenergy Research, R & D Centre, Indian Oil Corporation Ltd, Sector-13, Faridabad 121007, India
| | - Suresh K Puri
- DBT-IOC Centre for Advanced Bioenergy Research, R & D Centre, Indian Oil Corporation Ltd, Sector-13, Faridabad 121007, India
| | - Anshu Mathur
- DBT-IOC Centre for Advanced Bioenergy Research, R & D Centre, Indian Oil Corporation Ltd, Sector-13, Faridabad 121007, India
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Akula S, Golla N. Optimization of Cellulase Production by Aspergillus niger Isolated from Forest Soil. ACTA ACUST UNITED AC 2018. [DOI: 10.2174/1874070701812010256] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Background:An impressive increase in the application of cellulases in various fields over the last few decades demands extensive research in improving its quality and large-scale production. Therefore, the current investigation focuses on factors relevant for optimal production of cellulase byAspergillus nigerisolated from forest soil.Method:Throughout this study, the fungal strainAspergillus nigerwas maintained under the submerged condition for a period of 7 days at 120 rpm rotational speed. Various physical and chemical conditions were employed in examining their influence on cellulase production by the selected fungal strain. After appropriate incubation, culture filtrates were withdrawn and checked for FPase, CMCase, and β-D-glucosidase activities.Results:The optimum pH and temperature for cellulase production were found to be 5.0 and 32°C, respectively. Among the various carbon sources tested in the present study, amendment of lactose in the medium yielded peak values of FPase (filter paperase) and CMCase (Carboxy-methyl cellulase) whereas fructose supported the higher titers of β-glucosidase. Among the nitrogen sources, profound FPase and CMCase activity were recorded when urea was used but higher β-glucosidase activity was noticed when yeast extract was added. Various natural lignocellulosic substrates like bagasse, coir, corncob, groundnut shells, litter, rice bran, rice husk, sawdust and wheat bran were tested to find out the induction of cellulase. Among the lignocelluloses, sawdust and litter served as good substrates for cellulase production byAspergillus niger.Conclusion:In gist, the outcome of this study sheds light on the cellulolytic potentiality of the fungal strainAspergillus nigerpromising in its future commercial applications which may be economically feasible.
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Partial Purification and Characterization of Cellulolytic Enzymes Extracted from Trichoderma reesei Inoculated Digested Biogas Slurry. JOURNAL OF PURE AND APPLIED MICROBIOLOGY 2017. [DOI: 10.22207/jpam.11.4.37] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Comparative genome analyses of novel Mangrovimonas -like strains isolated from estuarine mangrove sediments reveal xylan and arabinan utilization genes. Mar Genomics 2016; 25:115-121. [DOI: 10.1016/j.margen.2015.12.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Revised: 12/09/2015] [Accepted: 12/16/2015] [Indexed: 11/22/2022]
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Cherian E, Dharmendirakumar M, Baskar G. Immobilization of cellulase onto MnO2 nanoparticles for bioethanol production by enhanced hydrolysis of agricultural waste. CHINESE JOURNAL OF CATALYSIS 2015. [DOI: 10.1016/s1872-2067(15)60906-8] [Citation(s) in RCA: 109] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Rahman MM, Inoue A, Ojima T. Characterization of a GHF45 cellulase, AkEG21, from the common sea hare Aplysia kurodai. Front Chem 2014; 2:60. [PMID: 25147784 PMCID: PMC4123733 DOI: 10.3389/fchem.2014.00060] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2014] [Accepted: 07/15/2014] [Indexed: 11/18/2022] Open
Abstract
The common sea hare Aplysia kurodai is known to be a good source for the enzymes degrading seaweed polysaccharides. Recently four cellulases, i.e., 95, 66, 45, and 21 kDa enzymes, were isolated from A. kurodai (Tsuji et al., 2013). The former three cellulases were regarded as glycosyl-hydrolase-family 9 (GHF9) enzymes, while the 21 kDa cellulase was suggested to be a GHF45 enzyme. The 21 kDa cellulase was significantly heat stable, and appeared to be advantageous in performing heterogeneous expression and protein-engineering study. In the present study, we determined some enzymatic properties of the 21 kDa cellulase and cloned its cDNA to provide the basis for the protein engineering study of this cellulase. The purified 21 kDa enzyme, termed AkEG21 in the present study, hydrolyzed carboxymethyl cellulose with an optimal pH and temperature at 4.5 and 40°C, respectively. AkEG21 was considerably heat-stable, i.e., it was not inactivated by the incubation at 55°C for 30 min. AkEG21 degraded phosphoric-acid-swollen cellulose producing cellotriose and cellobiose as major end products but hardly degraded oligosaccharides smaller than tetrasaccharide. This indicated that AkEG21 is an endolytic β-1,4-glucanase (EC 3.2.1.4). A cDNA of 1013 bp encoding AkEG21 was amplified by PCR and the amino-acid sequence of 197 residues was deduced. The sequence comprised the initiation Met, the putative signal peptide of 16 residues for secretion and the catalytic domain of 180 residues, which lined from the N-terminus in this order. The sequence of the catalytic domain showed 47–62% amino-acid identities to those of GHF45 cellulases reported in other mollusks. Both the catalytic residues and the N-glycosylation residues known in other GHF45 cellulases were conserved in AkEG21. Phylogenetic analysis for the amino-acid sequences suggested the close relation between AkEG21 and fungal GHF45 cellulases.
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Affiliation(s)
- Mohammad M Rahman
- Laboratory of Marine Biotechnology and Microbiology, Division of Applied Marine Life Science, Graduate School of Fisheries Sciences, Hokkaido University Hakodate, Japan ; Department of Fisheries Biology and Genetics, Bangladesh Agricultural University Mymensingh, Bangladesh
| | - Akira Inoue
- Laboratory of Marine Biotechnology and Microbiology, Division of Applied Marine Life Science, Graduate School of Fisheries Sciences, Hokkaido University Hakodate, Japan
| | - Takao Ojima
- Laboratory of Marine Biotechnology and Microbiology, Division of Applied Marine Life Science, Graduate School of Fisheries Sciences, Hokkaido University Hakodate, Japan
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Shahzadi T, Mehmood S, Irshad M, Anwar Z, Afroz A, Zeeshan N, Rashid U, Sughra K. Advances in lignocellulosic biotechnology: A brief review on lignocellulosic biomass and cellulases. ACTA ACUST UNITED AC 2014. [DOI: 10.4236/abb.2014.53031] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Optimization of cellulase production using Trichoderma reesei by RSM and comparison with genetic algorithm. Front Chem Sci Eng 2012. [DOI: 10.1007/s11705-012-1225-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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12
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Alkaliphilic bacteria: applications in industrial biotechnology. J Ind Microbiol Biotechnol 2011; 38:769-90. [DOI: 10.1007/s10295-011-0968-x] [Citation(s) in RCA: 91] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2011] [Accepted: 03/26/2011] [Indexed: 11/26/2022]
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Gautam SP, Bundela PS, Pandey AK, Khan J, Awasthi MK, Sarsaiya S. Optimization for the production of cellulase enzyme from municipal solid waste residue by two novel cellulolytic fungi. BIOTECHNOLOGY RESEARCH INTERNATIONAL 2011; 2011:810425. [PMID: 21350668 PMCID: PMC3042683 DOI: 10.4061/2011/810425] [Citation(s) in RCA: 109] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/13/2010] [Accepted: 12/24/2010] [Indexed: 11/20/2022]
Abstract
The main purpose of this study is to reduce the production cost of cellulase by optimizing the production medium and using an alternative carbon source such as municipal solid waste residue. In the present investigation, we aim to isolate the two novel cellulase producing fungi (Aspergillus niger and Trichoderma sp.) from municipal solid waste. Municipal solid waste residue (4-5% (w/v)) and peptone and yeast extract (1.0% (w/v)) were found to be the best combination of carbon and nitrogen sources for the production of cellulase by A. niger and Trichoderma sp. Optimum temperature and pH of the medium for the cellulase production by A. niger were 40°C and 6-7, whereas those for the production of cellulase by Trichoderma sp. were 45°C and 6.5. Cellulase production from A. niger and Trichoderma sp. can be an advantage as the enzyme production rate is normally higher as compared to other fungi.
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Affiliation(s)
- S P Gautam
- Central Pollution Control Board, New Delhi, India
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Li XH, Yang HJ, Roy B, Park EY, Jiang LJ, Wang D, Miao YG. Enhanced cellulase production of the Trichoderma viride mutated by microwave and ultraviolet. Microbiol Res 2010; 165:190-8. [DOI: 10.1016/j.micres.2009.04.001] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2009] [Revised: 03/30/2009] [Accepted: 04/18/2009] [Indexed: 11/26/2022]
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Fluorescence study on Interactions of α–Crystallin with the Molten Globule State of 1, 4–β–D–Glucan Glucanohydrolase from Thermomonospora sp. induced by guanidine hydrochloride. J Fluoresc 2009; 19:967-73. [DOI: 10.1007/s10895-009-0496-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2009] [Accepted: 06/05/2009] [Indexed: 10/20/2022]
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Cho KM, Hong SJ, Math RK, Islam SMA, Kim JO, Lee YH, Kim H, Yun HD. Cloning of two cellulase genes from endophytic Paenibacillus polymyxa GS01 and comparison with cel 44C-man 26A. J Basic Microbiol 2009; 48:464-72. [PMID: 18759236 DOI: 10.1002/jobm.200700281] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Endophytic bacteria are acknowledged as a new source of genes, proteins and other biochemical compounds, which are often used in biochemical processes. In this study, Paenibacillus polymyxa GS01 was isolated from the interior of the roots of Korean cultivars of ginseng (Panax ginseng C. A. Meyer). Two cellulase genes, cel 5A and cel 5B, were cloned from GS01, and encode 334 aa and 573 aa proteins, respectively. Cel5A and Cel5B each contain a glycosyl hydrolase family 5 (GH5) catalytic domain. The molecular mass of Cel5A and Cel5B were estimated to be 33 kDa and 61 kDa, respectively, by CMC-SDS-PAGE. When purified from Escherichia coli Cel5A and Cel5B both displayed cellulase activity with pH optima of 7.0 and 6.0, respectively and shared a temperature optimum of 50 degrees C. Neither enzyme had detectable xylanase, lichenase, or mannase activity, in contrast to the multifunctional Cel44C-Man26A enzyme of P. polymyxa which displays cellulase, xylanase, lichenase and mannanase activities. However, Cel5A and Cel5B exhibited higher specific cellulase activity than Cel44C-Man26A (120% and 140%, respectively). Cel5A and Cel5B mutants with alanine substitutions at a conserved glutamic acid in the GH5 domain (Glu 179 of Cel5A and Glu184 of Cel5B) lacked cellulase activity, suggesting that this residue is important for GH5 domain function.
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Affiliation(s)
- Kye Man Cho
- Division of Applied Life Science, Gyeongsang National University, Chinju, Korea
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Cho KM, Math RK, Hong SY, Asraful Islam SM, Kim JO, Hong SJ, Kim H, Yun HD. Changes in the activity of the multifunctional β-glycosyl hydrolase (Cel44C-Man26A) from Paenibacillus polymyxa by removal of the C-terminal region to minimum size. Biotechnol Lett 2008; 30:1061-8. [DOI: 10.1007/s10529-008-9640-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2007] [Revised: 01/07/2008] [Accepted: 01/07/2008] [Indexed: 11/27/2022]
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Anish R, Rao M. Biochemical characterization of a novel β-1–3, 1–4 glucan 4-glucanohydrolase from Thermomonospora sp. having a single active site for lichenan and xylan. Biochimie 2007; 89:1489-97. [PMID: 17689169 DOI: 10.1016/j.biochi.2007.06.010] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2007] [Accepted: 06/19/2007] [Indexed: 11/30/2022]
Abstract
A bifunctional high molecular weight (Mr, 64,500 Da) beta-1-3, 1-4 glucan 4-glucanohydrolase was purified to homogeneity from Thermomonospora sp., exhibiting activity towards lichenan and xylan. A kinetic method was used to analyze the active site that hydrolyzes lichenan and xylan. The experimental data was in agreement with the theoretical values calculated for a single active site. Probing the conformation and microenvironment at active site of the enzyme by fluorescent chemo-affinity label, OPTA resulted in the formation of an isoindole derivative with complete inactivation of the enzyme to hydrolyse both lichenan and xylan confirmed the results of kinetic method. OPTA forms an isoindole derivative by cross-linking the proximal thiol and amino groups. The modification of cysteine and lysine residues by DTNB and TNBS respectively abolished the ability of the enzyme to form an isoindole derivative with OPTA, indicating the participation of cysteine and lysine in the formation of isoindole complex.
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Affiliation(s)
- Ramakrishnan Anish
- Biochemical Sciences Division, National Chemical Laboratory, Dr. Homi Bhabha Road, Pashan, Pune, Maharashtra 411008, India
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Paljevac M, Primožič M, Habulin M, Novak Z, Knez Ž. Hydrolysis of carboxymethyl cellulose catalyzed by cellulase immobilized on silica gels at low and high pressures. J Supercrit Fluids 2007. [DOI: 10.1016/j.supflu.2007.05.006] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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20
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Molecular cloning and characterization of two novel cellulase genes from the mollusc Ampullaria crossean. J Comp Physiol B 2007; 178:209-15. [DOI: 10.1007/s00360-007-0214-z] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2007] [Revised: 09/01/2007] [Accepted: 09/15/2007] [Indexed: 10/22/2022]
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Anish R, Rahman MS, Rao M. Application of cellulases from an alkalothermophilic Thermomonospora sp. in biopolishing of denims. Biotechnol Bioeng 2007; 96:48-56. [PMID: 16952150 DOI: 10.1002/bit.21175] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Use of cellulase for denim washing is a standard eco-friendly technique to achieve desirable appearance and softness for cotton fabrics and denims. But enzymatic washing of denim till date involved acid cellulase (Trichoderma reesei) and neutral cellulase (Humicola isolens) the use of which has a drawback of backstaining of the indigo dye on to the fabric. Though it has been suggested that pH is a major factor in controlling backstaining there are no reports on use of cellulase under alkaline conditions for denim washing. In this study for the first time an alkali stable endoglucanase from alkalothermophilic Thermomonospora sp. (T-EG) has been used for denim biofinishing under alkaline conditions. T-EG is effective in removing hairiness with negligible weight loss and imparting softness to the fabric. Higher abrasive activity with lower backstaining was a preferred property for denim biofinishing exhibited by T-EG. The activities were comparable to acid and neutral cellulases that are being regularly used. The enzyme was also effective under non-buffering conditions which is an added advantage for use in textile industry. A probable mechanism of enzymatic finishing of cotton fabric has been represented based on the unique properties of T-EG.
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Affiliation(s)
- Ramakrishnan Anish
- Biochemical Sciences Division, National Chemical Laboratory, Pune, India
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Jagtap S, Rao M. Conformation and microenvironment of the active site of a low molecular weight 1,4-β-d-glucan glucanohydrolase from an alkalothermophilic Thermomonospora sp.: Involvement of lysine and cysteine residues. Biochem Biophys Res Commun 2006; 347:428-32. [PMID: 16828055 DOI: 10.1016/j.bbrc.2006.06.100] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2006] [Accepted: 06/16/2006] [Indexed: 11/26/2022]
Abstract
Conformation and microenvironment at the active site of 1,4-beta-D-glucan glucanohydrolase was probed with fluorescent chemo-affinity labeling using o-phthalaldehyde. OPTA has been known to form a fluorescent isoindole derivative by cross-linking the proximal thiol and amino groups of cysteine and lysine. Modification of lysine of the enzyme by TNBS and of cysteine residue by PHMB abolished the ability of the enzyme to form an isoindole derivative with OPTA. Kinetic analysis of the TNBS and PHMB-modified enzyme suggested the presence of essential lysine and cysteine residues, respectively, at the active site of the enzyme. The substrate protection of the enzyme with carboxymethylcellulose (CMC) confirmed the involvement of lysine and cysteine residues in the active site of the enzyme. Multiple sequence alignment of peptides obtained by tryptic digestion of the enzyme showed cysteine is one of the conserved amino acids corroborating the chemical modification studies.
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Affiliation(s)
- Sharmili Jagtap
- Division of Biochemical Sciences, National Chemical Laboratory, Dr. Homi Bhabha Road, Pune 411 008, India
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Manikandan K, Jagtap S, Rao M, Ramakumar S. Crystallization and preliminary X-ray characterization of a thermostable low-molecular-weight 1,4-beta-D-glucan glucohydrolase from an alkalothermophilic Thermomonospora sp. Acta Crystallogr Sect F Struct Biol Cryst Commun 2006; 62:385-7. [PMID: 16582491 PMCID: PMC2222567 DOI: 10.1107/s1744309106007949] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2006] [Accepted: 03/04/2006] [Indexed: 11/10/2022]
Abstract
Cellulases catalyze the hydrolysis of beta-1,4-glycosidic linkages within cellulose, the most abundant organic polymer on earth. The cellulase (TSC; EC 3.2.1.4) from an alkalothermophilic Thermomonospora sp. has a low molecular weight of 14.2 kDa. It is optimally active at 323 K and stable over the wide pH range of 5-9. Moreover, it has bifunctional activity against cellulose and xylan polymers. In this study, TSC was purified from the native source and crystallized by the hanging-drop vapour-diffusion method. The crystals belong to the orthorhombic space group P2(1)2(1)2(1), with unit-cell parameters a = 49.9, b = 79.5, c = 99.7 angstroms, and diffract to better than 2.3 angstroms resolution.
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Affiliation(s)
- K. Manikandan
- Department of Physics, Indian Institute of Science, Bangalore 560 012, India
| | - S. Jagtap
- Division of Biochemical Sciences, National Chemical Laboratory, Pune 411 008, India
| | - M. Rao
- Division of Biochemical Sciences, National Chemical Laboratory, Pune 411 008, India
| | - S. Ramakumar
- Department of Physics, Indian Institute of Science, Bangalore 560 012, India
- Bioinformatics Centre, Indian Institute of Science, Bangalore 560 012, India
- Correspondence e-mail:
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