401
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Aijun Z, Hongzhang C, Zuohu L. Air pressure pulsation solid state production of alkaline protease by Bacillus pumilus 1.1625. Process Biochem 2005. [DOI: 10.1016/j.procbio.2004.02.027] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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402
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403
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Optimizing some factors affecting alkaline protease production by a marine bacterium Teredinobacter turnirae under solid substrate fermentation. Process Biochem 2005. [DOI: 10.1016/j.procbio.2004.07.010] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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404
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Joo HS, Koo YM, Choi JW, Chang CS. Stabilization method of an alkaline protease from inactivation by heat, SDS and hydrogen peroxide. Enzyme Microb Technol 2005. [DOI: 10.1016/j.enzmictec.2005.01.002] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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405
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406
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Alkaline protease production by a soil isolate of Beauveria felina under SSF condition: parameter optimization and application to soy protein hydrolysis. Process Biochem 2005. [DOI: 10.1016/j.procbio.2004.03.006] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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407
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Subbian E, Yabuta Y, Shinde UP. Folding Pathway Mediated by an Intramolecular Chaperone: Intrinsically Unstructured Propeptide Modulates Stochastic Activation of Subtilisin. J Mol Biol 2005; 347:367-83. [PMID: 15740747 DOI: 10.1016/j.jmb.2005.01.028] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2004] [Revised: 01/04/2005] [Accepted: 01/11/2005] [Indexed: 11/21/2022]
Abstract
Several secreted proteases are synthesized with N-terminal propeptides that function as intramolecular chaperones (IMCs) and direct the folding of proteases to their native functional states. Using subtilisin E as our model system, we had earlier established that (i) release and degradation of the IMC from its complex with the protease upon completion of folding is the rate-determining step to protease maturation and, (ii) IMC of SbtE is an extremely charged, intrinsically unstructured polypeptide that adopts an alpha-beta structure only in the presence of the protease. Here, we explore the mechanism of IMC release and the intricate relationship between IMC structure and protease activation. We establish that the release of the first IMC from its protease domain is a non-deterministic event that subsequently triggers an activation cascade through trans-proteolysis. By in silico simulation of the protease maturation pathway through application of stochastic algorithms, we further analyze the sub-stages of the release step. Our work shows that modulating the structure of the IMC domain through external solvent conditions can vary both the time and randomness of protease activation. This behavior of the protease can be correlated to varying the release-rebinding equilibrium of IMC, through simulation. Thus, a delicate balance underlies IMC structure, release, and protease activation. Proteases are ubiquitous enzymes crucial for fundamental cellular processes and require deterministic activation mechanisms. Our work on SbtE establishes that through selection of an intrinsically unstructured IMC domain, nature appears to have selected for a viable deterministic handle that controls a fundamentally random event. While this outlines an important mechanism for regulation of protease activation, it also provides a unique approach to maintain industrially viable subtilisins in extremely stable states that can be activated at will.
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Affiliation(s)
- Ezhilkani Subbian
- Department of Biochemistry and Molecular Biology, MRB-631, Oregon Health and Sciences University, 3181 S. W. Sam Jackson Park Road, Mail Code L224, Portland, OR 97239-3098, USA
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408
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Ten LN, Im WT, Kim MK, Lee ST. A plate assay for simultaneous screening of polysaccharide- and protein-degrading micro-organisms. Lett Appl Microbiol 2005; 40:92-8. [PMID: 15644106 DOI: 10.1111/j.1472-765x.2004.01637.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
AIMS To develop a plate assay for simultaneous screening of polysaccharide-degrading and protein-degrading micro-organisms. METHODS AND RESULTS A plate assay, based on the visible solubilization of small substrate particles and the formation of haloes on Petri dishes, containing a mixture of diversely coloured insoluble polysaccharides and dye-labelled collagen as chromogenic substrates, was developed. This method was successfully applied for isolating the diverse polysaccharide- and/or protein-degrading bacteria from soil and sludge samples. Selected strains were identified using 16S rDNA partial sequencing; most of them belong to the genera Bacillus, Cellulomonas and Cellulosimicrobium. CONCLUSIONS This novel approach provides unique and valuable information for direct primary screening when the target of selection is micro-organisms exhibiting protein-degrading activity, polysaccharide-degrading activity or a specific combination of them. SIGNIFICANCE AND IMPACT OF THE STUDY This plate assay is convenient and easy to perform, rapid, and more adaptable for screening of a large number of samples, compared with other existing methods in the literature.
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Affiliation(s)
- L N Ten
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Kuseong-Dong, Yuseong-Gu, Daejeon, Korea
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409
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Yezza A, Tyagi RD, Valèro JR, Surampalli RY, Smith J. Scale-up of biopesticide production processes using wastewater sludge as a raw material. J Ind Microbiol Biotechnol 2004; 31:545-52. [PMID: 15662544 DOI: 10.1007/s10295-004-0176-z] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2004] [Accepted: 09/10/2004] [Indexed: 11/25/2022]
Abstract
Studies were conducted on the production of Bacillus thuringiensis (Bt)-based biopesticides to ascertain the performance of the process in shake flasks, and in two geometrically similar fermentors (15 and 150 l) utilizing wastewater sludge as a raw material. The results showed that it was possible to achieve better oxygen transfer in the larger capacity fermentor. Viable cell counts increased by 38-55% in the bioreactor compared to shake flasks. As for spore counts, an increase of 25% was observed when changing from shake flask to fermentor experiments. Spore counts were unchanged in bench (15 l) and pilot scale (5.3-5.5 e(+08) cfu/ml; 150 l). An improvement of 30% in the entomotoxicity potential was obtained at pilot scale. Protease activity increased by two to four times at bench and pilot scale, respectively, compared to the maximum activity obtained in shake flasks. The maximum protease activity (4.1 IU/ml) was obtained in pilot scale due to better oxygen transfer. The Bt fermentation process using sludge as raw material was successfully scaled up and resulted in high productivity for toxin protein yield and a high protease activity.
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Affiliation(s)
- A Yezza
- INRS Eau, Terre et Environnement (INRS-ETE), 2800 Rue Einstein, CP 7500, Sainte-Foy, QC, G1V4C7, Canada
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410
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Chauhan B, Gupta R. Application of statistical experimental design for optimization of alkaline protease production from Bacillus sp. RGR-14. Process Biochem 2004. [DOI: 10.1016/j.procbio.2003.11.002] [Citation(s) in RCA: 107] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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411
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Akbalik G, Gunes H, Yavuz E, Yasa I, Harsa S, Elmaci ZS, Yenidunya AF. Identification of extracellular enzyme producing alkalophilic bacilli from Izmir province by 16S-ITS rDNA RFLP. J Appl Microbiol 2004; 97:766-73. [PMID: 15357726 DOI: 10.1111/j.1365-2672.2004.02357.x] [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] [Indexed: 11/27/2022]
Abstract
AIMS To screen industrially important extracellular enzymes from the newly isolated alkalophilic bacilli and to characterize them by phenotypic and 16S-internal transcribed spacer (ITS) rDNA restriction pattern analysis. METHODS AND RESULTS Three different environmental samples, soil, leather and horse faeces, were collected within the province of Izmir. Isolates grown on Horikoshi-I medium for 24 h at 37 degrees C were screened for extracellular enzyme activity by using eight different substrates: birchwood xylan, carboxymethylcellulose, casein, citrus pectin, polygalacturonic acid, soluble starch, and Tween 20 and 80. In total, 115 extracellular enzyme-producing bacilli were obtained. Casein was hydrolysed by 78%, soluble starch by 67%, citrus pectin by 63%, polygalacturonic acid by 62%, Tween 20 by 34%, birchwood xylan by 16%, Tween 80 by 12%, and carboxymethylcellulose by 3% of the isolates. The isolates were differentiated into 19 distinct homology groups by the 16S-ITS rDNA restriction pattern analysis. CONCLUSIONS Eight different extracellular enzyme activities were determined in 115 endospore forming bacilli. The largest 16S-ITS rDNA homology group (HT1) included 36% of the isolates, 98% of which degraded casein, polygalacturonic acid, pectin and starch. SIGNIFICANCE AND IMPACT OF THE STUDY This study is the first report on the characterization of the industrial enzyme-producing alkalophilic bacilli by 16S-ITS rDNA restriction fragment length polymorphism (RFLP). Restriction profiles of 64% of the isolates were found to be different from those of five reference strains used.
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Affiliation(s)
- G Akbalik
- Biotechnology and Bioengineering Programme, Science Faculty, Izmir Institute of Technology, Gulbahce, Izmir, Turkey
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412
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Chen XG, Stabnikova O, Tay JH, Wang JY, Tay STL. Thermoactive extracellular proteases of Geobacillus caldoproteolyticus, sp. nov., from sewage sludge. Extremophiles 2004; 8:489-98. [PMID: 15322950 DOI: 10.1007/s00792-004-0412-5] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2003] [Accepted: 06/11/2004] [Indexed: 10/26/2022]
Abstract
A proteolytic thermophilic bacterial strain, designated as strain SF03, was isolated from sewage sludge in Singapore. Strain SF03 is a strictly aerobic, Gram stain-positive, catalase-positive, oxidase-positive, and endospore-forming rod. It grows at temperatures ranging from 35 to 65 degrees C, pH ranging from 6.0 to 9.0, and salinities ranging from 0 to 2.5%. Phylogenetic analyses revealed that strain SF03 was most similar to Saccharococcus thermophilus, Geobacillus caldoxylosilyticus, and G. thermoglucosidasius, with 16S rRNA gene sequence identities of 97.6, 97.5 and 97.2%, respectively. Based on taxonomic and 16S rRNA analyses, strain SF03 was named G. caldoproteolyticus sp. nov. Production of extracellular protease from strain SF03 was observed on a basal peptone medium supplemented with different carbon and nitrogen sources. Protease production was repressed by glucose, lactose, and casamino acids but was enhanced by sucrose and NH4Cl. The cell growth and protease production were significantly improved when strain SF03 was cultivated on a 10% skim-milk culture medium, suggesting that the presence of protein induced the synthesis of protease. The protease produced by strain SF03 remained active over a pH range of 6.0-11.0 and a temperature range of 40-90 degrees C, with an optimal pH of 8.0-9.0 and an optimal temperature of 70-80 degrees C, respectively. The protease was stable over the temperature range of 40-70 degrees C and retained 57 and 38% of its activity at 80 and 90 degrees C, respectively, after 1 h.
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Affiliation(s)
- Xiao-Ge Chen
- Environmental Engineering Research Center, School of Civil and Environmental Engineering, Nanyang Technological University, 639798, Singapore
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413
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Bleach-resistant alkaline protease produced by a Bacillus sp. isolated from the Korean polychaete, Periserrula leucophryna. Process Biochem 2004. [DOI: 10.1016/s0032-9592(03)00260-7] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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414
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Investigations on alkaline protease production with B. subtilis PE-11 immobilized in calcium alginate gel beads. Process Biochem 2004. [DOI: 10.1016/s0032-9592(03)00263-2] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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415
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Agrawal D, Patidar P, Banerjee T, Patil S. Production of alkaline protease by Penicillium sp. under SSF conditions and its application to soy protein hydrolysis. Process Biochem 2004. [DOI: 10.1016/s0032-9592(03)00212-7] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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416
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Denizci AA, Kazan D, Abeln ECA, Erarslan A. Newly isolated Bacillus clausii GMBAE 42: an alkaline protease producer capable to grow under higly alkaline conditions. J Appl Microbiol 2004; 96:320-7. [PMID: 14723693 DOI: 10.1046/j.1365-2672.2003.02153.x] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
AIMS The isolation and identification of new Bacillus sp. capable of growing under highly alkaline conditions as alkaline protease producers. METHODS AND RESULTS A Bacillus strain capable of growing under highly alkaline conditions was isolated from compost. The strain is a Gram-positive, spore-forming, motile, aerobic, catalase- and oxidase-positive, alkaliphilic bacterium and designated as GMBAE 42. Good growth of the strain was observed at pH 10. The strain was identified as Bacillus clausii according to the physiological properties, cellular fatty acid composition, G + C content of genomic DNA and 16S rRNA gene sequence analyses. The result of 16S rRNA sequence analyses placed this bacterium in a cluster with B. clausii. The G + C content of the genomic DNA of the isolate GMBAE 42 was found to be 49 mol%. The crude extracellular alkaline protease produced by the isolate showed maximal activity at pH 11.0 and 60 degrees C. CONCLUSIONS The results suggest that isolated strain GMBAE 42 is a new type of B. clausii capable of growing at pH 10.0 and produce extracellular alkaline protease very active at pH 11.0. SIGNIFICANCE AND IMPACT OF THE STUDY Isolated strain could be used in commercial alkaline protease production and its enzyme can be considered as a candidate as an additive for commercial detergents.
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Affiliation(s)
- A A Denizci
- Research Institute for Genetic Engineering and Biotechnology, Marmara Research Center Campus, The Scientific and Technical Research Council of Turkey, Gebze, Kocaeli, Turkey.
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417
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Joo HS, Kumar CG, Park GC, Paik SR, Chang CS. Oxidant and SDS-stable alkaline protease from Bacillus clausii I-52: production and some properties. J Appl Microbiol 2003; 95:267-72. [PMID: 12859757 DOI: 10.1046/j.1365-2672.2003.01982.x] [Citation(s) in RCA: 126] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
AIMS An investigation was carried out on an oxidative and SDS-stable alkaline protease secreted by Bacillus clausii of industrial significance. METHODS AND RESULTS Maximum enzyme activity was produced when the bacterium was grown in the medium containing (g l-1): soyabean meal, 15; wheat flour, 10; liquid maltose, 25; K2HPO4, 4; Na2HPO4, 1; MgSO4.7H2O, 0.1; Na2CO3, 6. The enzyme has an optimum pH of around 11 and optimum temperature of 60 degrees C. The alkaline protease showed extreme stability towards SDS and oxidizing agents, which retained its activity above 75 and 110% on treatment for 72 h with 5% SDS and 10% H2O2, respectively. Inhibition profile exhibited by phenylmethylsulphonyl fluoride suggested that the protease from B. clausii belongs to the family of serine proteases. CONCLUSIONS Bacillus clausii produced high levels of an extracellular protease having high stability towards SDS and H2O2. SIGNIFICANCE AND IMPACT OF THE STUDY The alkaline protease from B. clausii I-52 is significant for an industrial perspective because of its ability to function in broad pH and temperature ranges in addition to its tolerance and stability in presence of an anionic surfactant, like SDS and oxidants like peroxides and perborates. The enzymatic properties of the protease also suggest its suitable application as additive in detergent formulations.
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Affiliation(s)
- H-S Joo
- Institute of Medical Science and Department of Biochemistry, College of Medicine, Inha University, Inchon, Korea
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418
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Elibol M, Moreira AR. Production of extracellular alkaline protease by immobilization of the marine bacterium Teredinobacter turnirae. Process Biochem 2003. [DOI: 10.1016/s0032-9592(03)00024-4] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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419
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Bakhtiar S, Andersson MM, Gessesse A, Mattiasson B, Hatti-Kaul R. Stability characteristics of a calcium-independent alkaline protease from Nesterenkonia sp. Enzyme Microb Technol 2003. [DOI: 10.1016/s0141-0229(02)00336-8] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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420
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Joo HS, Kumar C, Park GC, Kim KT, Paik SR, Chang CS. Optimization of the production of an extracellular alkaline protease from Bacillus horikoshii. Process Biochem 2002. [DOI: 10.1016/s0032-9592(02)00061-4] [Citation(s) in RCA: 96] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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421
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Beg QK, Saxena RK, Gupta R. Kinetic constants determination for an alkaline protease from Bacillus mojavensis using response surface methodology. Biotechnol Bioeng 2002; 78:289-95. [PMID: 11920445 DOI: 10.1002/bit.10203] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The kinetic constants for an alkaline protease from Bacillus mojavensis were determined using a central composite circumscribed design (CCCD) where concentration of substrate (casein) and the assay temperature were varied around their center point. The K(m),V(max), K(cat), activation energy (E(a)) and temperature coefficient (q(10)) were determined and the values of these kinetic constants obtained were found comparable to that obtained with conventional methods. The Michaelis-Menten constant (K(m)) for casein decreased with corresponding increase in V(max), as reaction temperature was raised from 45-60 degrees C. The protease exhibited K(m) of 0.0357 mg/ml, 0.0270 mg/ml, 0.0259 mg/ml, and 0.0250 mg/ml at 45, 50, 55, and 60 degrees C, respectively, whereas V(max) values at these temperatures were 74.07, 99.01, 116.28, and 120.48 microg/ml/min, respectively, as determined by response surface methodology. The Arrhenius plot suggested that the enzyme undergoes thermal activation above 45 degrees C until 60-65 degrees C followed by thermal inactivation. Likewise, the energy of activation (E(a)) was more between 45-55 degrees C (9747 cal/mol) compared to E(a) between 50-60 degrees C (4162 cal/mol).
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Affiliation(s)
- Qasim Khalil Beg
- Department of Microbiology, University of Delhi South Campus, Benito Juarez Marg, New Delhi 110 021, India.
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422
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De Toni CH, Richter MF, Chagas JR, Henriques JAP, Termignoni C. Purification and characterization of an alkaline serine endopeptidase from a feather-degrading Xanthomonas maltophilia strain. Can J Microbiol 2002; 48:342-8. [PMID: 12030707 DOI: 10.1139/w02-027] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A keratinolytic Xanthomonas maltophilia strain (POA-1), cultured on feather meal broth, using keratin as its sole source of carbon and nitrogen, secretes several extracellular peptidases. The major serine peptidase was purified to homogeneity by a five-step procedure. Its purity was evaluated by capillary zone electrophoresis. This enzyme has a molecular mass of 36 kDa, an optimum pH of 9.0, and an optimum temperature of 60 degrees C. The inhibitory profile using protease inhibitors shows that this enzyme is a serine endopeptidase. Besides keratin, the enzyme is active upon the substrates azokeratin, azocasein, and the following fluorogenic peptide substrates: Abz-Leu-Gly-Met-Ile-Ser-Leu-Met-Lys-Arg-Pro-Gln-EDDnp, Abz-Lys-Leu-Cys(SBzl)-Gly-Pro-Lys-Gln-EDDnp, and Abz-Lys-Pro-Cys(SBzl)-Phe-Ser-Lys-Gln-EDDnp.
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Affiliation(s)
- C H De Toni
- Departamento de Bioquímica and Centro de Biotecnologia, UFRGS, Porto Alegre, RS, Brazil
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423
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Kumar CG. Purification and characterization of a thermostable alkaline protease from alkalophilic Bacillus pumilus. Lett Appl Microbiol 2002; 34:13-7. [PMID: 11849485 DOI: 10.1046/j.1472-765x.2002.01044.x] [Citation(s) in RCA: 78] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
AIMS An investigation was carried out on the purification and characterization of an alkaline protease from Bacillus pumilus MK6-5. METHODS AND RESULTS An alkalophilic Bacillus pumilus MK6-5 was grown in a laboratory fermenter containing 1% reverse osmosis concentrated cheese whey powder, 0.25% corn steep liquor, 1% glucose, 0.5% tryptone, 1% sodium citrate, 0.02% MgSO4.7H2O and 0.65% Na2CO3 at 35 degrees C and pH 9.6, agitation at 250 rev min(-1) and aeration of 1 vvm for 60 h. When the enzyme was purified using ammonium sulphate precipitation, ion exchange and gel filtration chromatographies, a 26.2% recovery of enzyme with 36.6-fold purification was recorded. The purified protease was found to be homogenous by SDS-PAGE with molecular mass estimate of 28 kDa. The enzyme was optimally active at pH 11.5 and temperature of 55-60 degrees C. The Km and kcat values observed with synthetic substrates at 37 degrees C and pH 8.0 were 1.1 mmol l(-1) and 624 s(-1) for Glu-Gly-Ala-Phe-pNA and 3.7 mmol l(-1) and 826 s(-1) for Glu-Ala-Ala-Ala-pNA, respectively. The kinetic data revealed that small aliphatic and aromatic residues were the preferred residues at the P1 position. Inhibition profile exhibited by PMSF suggested the B. pumilus protease to be an alkaline serine protease. CONCLUSIONS Bacillus pumilus MK6-5 produced a calcium-dependent, thermostable alkaline serine protease. SIGNIFICANCE AND IMPACT OF THE STUDY The thermostable alkaline protease from Bacillus pumilus MK6-5 will be extremely useful in ultrafiltration membrane cleaning due to its ability to work in broad pH and temperature ranges, and tolerance to detergents, unlike the mesophilic proteases which face these limitations.
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Affiliation(s)
- C G Kumar
- Molekularbiologisches Zentrum, Bundesforschungsanstalt für Ernährung, Haid und Neu Strasse 9, D-76131 Karlsruhe, Germany
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