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1.
Bacillus licheniformis 3C5, isolated as mesophilic bacterium, exhibited tolerance towards a wide range of non-polar and polar organic solvents at 45°C. It produced an extracellular organic solvent-stable protease with an apparent molecular mass of approximately 32 kDa. The inhibitory effect of PMSF and EDTA suggested it is likely to be an alkaline serine protease. The protease was active over a broad range of temperatures (45–70°C) and pH (8–10) range with an optimum activity at pH 10 and 65°C. It was comparatively stable in the presence of a relatively high concentration (35% (v/v)) of organic solvents and various types of detergents even at a relatively high temperature (45°C). The protease production by B. licheniformis 3C5 was growth-dependent. The optimization of carbon and nitrogen sources for cell growth and protease production revealed that yeast extract was an important medium component to support both cell growth and the protease production. The overall properties of the protease produced by B. licheniformis 3C5 suggested that this thermo-stable, solvent-stable, detergent-stable alkaline protease is a promising potential biocatalyst for industrial and environmental applications.  相似文献   

2.
A novel haloalkaliphilic bacterium designated as strain BNMIITR was isolated from a soil sample collected from Sambhar lake, Rajasthan, in northern India. Colonies of the isolated strain were dark orange and comprised Gram-negative bacilli; there was a slight pleomorphism towards the stationary phase of growth. Experiments revealed that the isolate can grow in the range of 2–5 M NaCl, pH 6–11 and 18–55 °C, with optimum growth observed at 3 M NaCl, pH 8–8.5 and 45 °C. No growth was observed in culture medium without NaCl. The isolate showed no requirement for magnesium sulphate heptahydrate (MgSO4 .7H2O) for growth. Major cellular fatty acids were C 14:0, C 15:0 iso, C 15:0 anteiso, C 16:0, C 17:0 iso, C 17:0 anteiso and C 20:2 w6, 9c. The result of 16S rRNA gene sequence analysis showed 98 % sequence similarity with Halobiforma lacisalsi and Hbf. haloterrestris. Halobiforma sp. strain BNMIITR showed resistance towards several antibiotics and produced an extracellular alkaline protease. The crude enzyme was found to be active in broad range of alkaline pH and temperature (30–80 °C).  相似文献   

3.
The effect of bioprocess conditions (pH and temperature) on the growth and alkaline protease production of halotolerant Bacillus licheniformis BA17 bioreactor cultures have been systematically analyzed using response surface methodology in order to assess the importance of these generally disregarded parameters. Two models were proposed differing by the choice of response variable. Under optimized bioprocess conditions, whole alkaline protease activity was about 3 fold higher than the activities obtained in the preliminary studies. Results of this study not only highlight the importance of pH and temperature for further engineering purposes but also serve as basis for understanding the true mechanism lying under the relation between these process parameters and growth and whole alkaline protease production. Published in Russian Prikladnaya Biokhimiya i Mikrobiologiya, 2008, Vol. 44, No. 5, pp. 539–544. The text was submitted by the autors in English.  相似文献   

4.
An organic solvent-stable alkaline protease producing bacterium was isolated from the crude oil contaminant soil and identified as Bacillus licheniformis. The enzyme retained more than 95% of its initial activity after pre-incubation at 40 °C for 1 h in the presence of 50% (v/v) organic solvents such as DMSO, DMF, and cyclohexane. The protease was active in a broad range of pH from 8.0 to 12.0 with the optimum pH 9.5. The optimum temperature for this protease activity was 60 °C, and the enzyme remained active after incubation at 50–60 °C for 1 h. This organic solvent-stable protease could be used as a biocatalyst for organic solvent-based enzymatic synthesis.  相似文献   

5.
This study explores a novel concept of coproduction of uricase and alkaline protease by Bacillus licheniformis using single substrate in single step. Seven local bacterial strains were screened for uricase production, amongst which B. licheniformis is found to produce highest uricase along with alkaline protease. Optimization of various factors influencing maximum enzyme coproduction by B. licheniformis is performed. Maximum enzyme productivity of 0.386?U/mL uricase and 0.507?U/mL alkaline protease is obtained at 8?hr of incubation period, 1% (v/v) inoculum, and at 0.2% (w/v) uric acid when the organism is cultivated at 25°C, 180?rpm, in a media containing xylose as a carbon source, urea as a nitrogen source, and initial pH of 9.5. The statistical experimental design method of Box–Behnken was further applied to obtain optimal concentration of significant parameters such as pH (9.5), uric acid concentration (0.1%), and urea concentration (0.05%). The maximum uricase and alkaline protease production by B. licheniformis using Box–Behnken design was 0.616 and 0.582?U/mL, respectively, with 1.6- and 1.13-fold increase as compared to one factor at a time optimized media. This study will be useful to develop an economic, commercially viable, and scalable process for simultaneous production of uricase and protease enzymes.  相似文献   

6.
In this paper, a new bacterial strain designated as 16MFT21T is isolated from the muscle of a fish caught in the Antarctic Ocean. Strain 16MFT21T is a Gram-staining-positive, catalase-oxidase-positive, rod-shaped facultative-aerobic bacterium. The phylogenetic analysis that is based on the 16S-rRNA gene sequence of strain 16MFT21T revealed that it belongs to the genus Bacillus in the family Bacillaceae in the class Bacilli. The highest degrees of the sequence similarity of the strain 16MFT21T is with Bacillus licheniformis ATCC 14580T (96.6%) and Bacillus sonorensis NBRC 101234T (96.6%). The isolate formed a pale-yellow pigment, and it grew in the presence of 0% to 10% (w/v) NaCl (optimum at 2% NaCl), a pH of 6.0 to 10.0 (optimum pH from 7.0 to 8.0), and from 4°C to 30°C (optimum at 30°C). The major polar lipids consist of diphosphatidylglycerol (DPG) and phosphatidylglycerol (PG). The predominant fatty acids are iso-C15:0, anteiso-C15:0, iso-C17:0, and anteiso-C17:0. The main respiratory quinone is menaquinone-7 (MK-7), and based on the use of the meso-diaminopimelic acid as the diagnostic diamino acid, the peptidoglycan cell-wall type is A1γ. Based on the phylogenetic, phenotypic, and chemotaxonomic data, strain 16MFT21T (=KCTC 18866T =JCM 31664T) for which the name Bacillus piscis sp. nov. is proposed should be classified as a new species.  相似文献   

7.
《Process Biochemistry》2007,42(5):791-797
An extracellular bleach stable protease from the fungus Aspergillus clavatus ES1, isolated from wastewater, was purified and characterized. The protease of ES1 strain was purified to homogeneity using acetone precipitation, Sephadex G-100 gel filtration and CM-Sepharose ion exchange chromatography, with a 7.5-fold increase in specific activity and 29% recovery. The molecular mass was estimated to be 32 kDa on SDS-PAGE. The optimum pH and temperature for the proteolytic activity were pH 8.5 and 50 °C, respectively. The enzyme was stable in the pH range of 7.0–9.0. The protease was activated by divalent cations such as Ca2+ and Mg2+.The alkaline protease showed extreme stability towards non-ionic surfactants (5% Tween 80 and 5% Triton X-100). In addition, the enzyme was relatively stable towards oxidizing agents, retaining more than 71 and 53% of its initial activity after 1 h incubation in the presence of 1 and 2% (w/v) sodium perborate, respectively.The N-terminal sequence of the first 15 amino acids of the purified alkaline protease of A. clavatus ES1 showed high similarity with other fungal alkaline proteases. The activity was totally lost in the presence of PMSF, suggesting that the purified enzyme is a serine-protease.  相似文献   

8.
A Gram-positive, aerobic, coccoid-rod shaped, non-motile, catalase- and oxidase-positive bacterium, designated strain KJW98T, was isolated from the marine sediment of Karwar jetty, west coast of India. The strain was β-haemolytic, non-endospore-forming and grew with 0–8.5% (w/v) NaCl, at 15–48°C and at pH 6.5–9.0, with optimum growth with 0.5% (w/v) NaCl, at 42°C and at pH 7.0–8.0. Phylogenetic analyses based on 16S rRNA and gyrB gene sequences showed that strain KJW98T forms a lineage within the genus Bhargavaea. The G+C content of the genomic DNA was 55 mol%. The DNA-DNA relatedness values of strain KJW98T with B. beijingensis DSM 19037T, B. cecembensis LMG 24411T and B. ginsengi DSM 19038T were 43.2, 39 and 26.5%, respectively. The major fatty acids were anteiso-C15:0 (37.7%), iso-C15:0 (19.7%), anteiso-C17:0 (17.0%) and iso-C16:0 (11.1%). The predominant menaquinone was MK-8 and the cell-wall peptidoglycan was of A4α type with L-lysine as the diagnostic diamino acid. The major polar lipids were diphosphatidylglycerol and phosphatidylglycerol. The phenotypic, genotypic and DNA-DNA relatedness data indicate that strain KJW98T should be distinguished from the members of the genus Bhargavaea, for which the name Bhargavaea indica sp. nov. is proposed with the type strain KJW98T (=KCTC 13583T =LMG 25219T).  相似文献   

9.
The current increase in the amount of shrimp wastes produced by the shrimp industry has led to the need in finding new methods for shrimp wastes disposal. In this study, Bacillus licheniformis RP1 was shown to produce proteases when grown in media containing shrimp wastes powder as a sole carbon and nitrogen source, indicating that this bacteria could obtain its carbon and nitrogen requirements directly from shrimp wastes. The maximum protease production was obtained when the strain was grown in a medium containing (g/L): shrimp wastes powder 30, KCl 1.5, K2HPO4 0.5, and KH2PO4 0.5. Using casein zymography, the crude protease preparation was found to produce at least seven proteases. The proteases of B. licheniformis RP1 were tested for shrimp waste deproteinization in the preparation of chitin. The percent of protein removal after 3 h hydrolysis at 60°C and at an enzyme/substrate (E/S) ratio of 0.5 and 5 (Unit of enzyme/mg of protein) were about 68 and 81%, respectively. Additionally, B. licheniformis RP1 showed important feather degrading activity. Complete solubilisation of whole feathers was observed after 24 h of incubation at 50°C. More interestingly, the RP1 proteolytic preparation demonstrated powerful dehairing capabilities for hair removal from skin. Collagen, which is the major leather-forming protein, was not significantly degraded. Considering its promising properties, B. licheniformis RP1 enzymatic preparation may be considered a potential candidate for future use in several biotechnological processes.  相似文献   

10.
An orange-colored bacterial strain, ICM 1–15T, was isolated from greenhouse soil. The 16S rRNA gene sequence of this strain showed the highest sequence similarity with Niabella ginsengisoli GR10-1T (95.2%) and Niabella yanshanensis CCBAU 05354T (95.0%) among the type strains. The strain ICM 1–15T was a strictly aerobic, Gram-negative, non-spore-forming, non-motile, flexirubin pigment-producing, short rod-shaped bacterium. The strain grew at 15–35°C (optimum, 25°C), at a pH of 5.0–8.5 (optimum, pH 6.5), and in the presence of 0–3% NaCl (optimum, 1%). The DNA G+C content of strain ICM 1–15T was 43.6 mol%. It contained MK-7 as the major isoprenoid quinone and iso-C15:0 (38.9%), iso-C15:1 G (20.3%), and iso-C17:0 3-OH (12.9%) as the major fatty acids. On the basis of evidence from our polyphasic taxonomic study, we concluded that strain ICM 1–15T should be classified within a novel species of the genus Niabella, for which the name Niabella terrae sp. nov. is proposed. The type strain is ICM 1–15T (=KACC 17443T =JCM 19502T).  相似文献   

11.
An investigation on the properties of an alkaline protease secreted by Bacillus circulans BM15 strain isolated from a mangrove sediment sample was carried out in order to characterize the enzyme and to test its potency as a detergent additive. The protease was purified to apparent homogeneity by ammonium sulphate precipitation and was a 30-kDa protease as shown by SDS-PAGE and its proteolytic activity was detected by casein zymography. It had optimum activity at pH 7, was stable at alkaline pH range (7 to 11), had optimum temperature of activity 40°C and was stable up to a temperature of 55°C after incubation for one hour. Hg2+, Zn2+, Co2+, and Cu2+completely inhibited the enzyme activity, while Ca2+, Mg2+, K+ and Fe3+ were enhancing the same. The serine protease inhibitor PMSF and metal chelator EDTA inhibited the activity of this protease while the classic metalloprotease inhibitor 1, 10 phenanthroline did not show inhibition. The enzyme was stable in SDS, Triton-X-100 and H2 O2 as well as in various commercial detergents after incubation for one hour. The extracellular production of the enzyme, the pH and temperature stability and stability in presence of oxidants, surfactants and commercial detergents suggest its possible use as a detergent additive.  相似文献   

12.
A novel process for the microbial production of alkaline protease on an industrial scale was successfully established by using a kabicidin resistant mutant, No. 5–128B, derived from Fusarium sp. S–19–5. The most suitable carbon source for producing alkaline protease was n-paraffins (C10~C14) and the effective nitrogen source was dried-yeast cells containing no nucleic acid, the optimum concentrations being 12.5% (w/v) and 7.0% (w/v), respectively. The optimal temperature and initial pH for protease production were 24°C and 6.0, respectively. Under the optimal conditions using a shaker flask mutant No. 5–128B produced 41000 PU/ml of alkaline protease, which corresponded to about 10 times the amount produced by the parent strain. The relation between the high ability to produce alkaline protease and the resistance to kabicidin, a polyene antibiotic, is discussed.  相似文献   

13.
Induced mutagenesis with γ-irradiation of the industrial strain Bacillus licheniformis-60 VKM B-2366 D was used to obtain a new highly active producer of an extracellular serine protease, Bacillus licheniformis-145. Samples of dry concentrated preparations of serine protease produced by the original and mutant strains were obtained, and identity of their protein composition was established. Alkaline serine protease subtilisin DY was the main component of the preparations. The biochemical and physicochemical properties of the Protolicheterm-145 enzyme preparation obtained from the mutant strain were studied. It exhibited proteolytic activity (1.5 times higher than the preparation from the initial strain) within broad ranges of pH (5–11) and temperature (30–70°C). Efficient hydrolysis of extruded soybean meal protein at high concentrations (20 to 50%) in the reaction mixture was the main advantage of the Protolicheterm-145 preparation. Compared to the preparation obtained using the initial strain, the new preparation with increased proteolytic activity provided for more complete hydrolysis of the main non-nutritious anti-nutritional soy proteins (glycinin and β-conglycinin) with the yield of soluble protein increased by 19–28%, which decreased the cost of bioconversion of the proteinaceous material and indicated promise of the new preparation in resource-saving technologies for processing soybean meals and cakes.  相似文献   

14.
For the purpose of obtaining microorganisms capable of producing alkaline protease inhibitor, screening test was carried out. One strain of microorganisms (No. S–3253) showed strong ability to produce alkaline protease inhibitor.

The morphological and physiological characteristics of strain S–3253 were studied. This strain was found to belong to Streptomyces albogriseolus.

When the strain S–3253 was cultivated at 45°C with a medium containing 4% polypepton, 2% starch, 0.1% yeast extract, 0.1% NaCl, 0.1% K2HPO4 and 0.05% MgSO4-7H2O in shake-flasks (pH 7.0), the highest activity was obtained after 40~48 hr cultivation.  相似文献   

15.
This study reports the purification and characterization of an extracellular haloalkaline serine protease from the moderately halophilic bacterium, Bacillus iranensis, strain X5B. The enzyme was purified to homogeneity by acetone precipitation, ultrafiltration and carboxymethyl (CM) cation exchange chromatography, respectively. The purified protease was a monomeric enzyme with a relative molecular mass of 48–50 kDa and it was inhibited by PMSF indicating that it is a serine-protease. The optimum pH, temperature and NaCl concentration were 9.5, 35 °C and 0.98 M, respectively. The enzyme showed a significant tolerance to salt and alkaline pH. It retained approximately 50 % of activity at 2.5 M NaCl and about 70 % of activity at highly alkaline pH of 11.0; therefore, it was a moderately halophilic and also can be activated by metals, especially by Ca2+. The specific activity of the purified protease was measured to be 425.23 μmol of tyrosine/min per mg of protein using casein as a substrate. The apparent K m and V max values were 0.126 mM and 0.523 mM/min, respectively and the accurate value of k cat was obtained as 3.284 × 10?2 s?1. These special and important characteristics make this serine protease as valuable tool for industrial applications.  相似文献   

16.
《Process Biochemistry》2010,45(7):1148-1155
The protease from the latex of Calotropis procera was isolated by an aqueous two-phase system (ATPS). The systems consist of polyethylene glycol (PEG 4000, 6000 and 8000) at concentrations of 9, 12 and 15% (w/w) with salts (Na-citrate, MgSO4, K2HPO4, and (NH4)2SO4) at concentrations of 11, 14 and 17% (w/w) were investigated. The highest protease recovery was found in the PEG-rich phase of the system, comprising of 12% PEG 4000–17% MgSO4. For optimization of the system to obtain the higher yield of protease, the system pH (4, 7 and 10) or NaCl addition (2, 4 and 6%, w/w) was studied. At acidic (pH 4.0) and alkaline (9.0) conditions of the systems the reduction of KE and protease recovery was clearly observed compared to that of the neutral pH (7.0). The addition of NaCl up to a final concentration of 6% (w/w) significantly increased the yield to 107% of the control. Molecular weight distribution and activity staining showed that the isolated protease had the molecular weight of ∼38 kDa. However, the isolated protease had no activity under reducing condition (βME). Under cathodic electrophoresis, protease from C. procera showed the same protein pattern to purified papain.  相似文献   

17.
An extracellular bleach stable protease producing strain was isolated from marine water sample and identified as Bacillus mojavensis A21 on the basis of the 16S rRNA gene sequencing and biochemical properties. The A21 alkaline protease was purified from the culture supernatant to homogeneity using acetone precipitation, Sephadex G-75 gel filtration and CM-Sepharose ion exchange chromatography, with a 6.43-fold increase in specific activity and 16.56% recovery. The molecular weight of the purified enzyme was estimated to be 20 kDa by SDS-PAGE and gel filtration. The enzyme was highly active over a wide range of pH from 7.0 to 13.0, with an optimum at pH 8.5. The relative activities at pH 11.0 and 12.0 were about 80 and 71.7% of that obtained at pH 8.5. The enzyme was extremely stable in the pH range of 7.0–12.0. It exhibited maximal activity at 60 °C. The thermostability of the enzyme was significantly increased by the addition of CaCl2. The activity of the enzyme was totally lost in the presence of PMSF, suggesting that the purified enzyme is a serine protease.The N-terminal amino acid sequence of the first 20 amino acids of the purified protease was DINGGGATLPQKLYQTSGVL. B. mojavensis A21 protease showed low homology with bacterial peptidases, suggesting that the enzyme is a new protease.The alkaline protease showed high stability towards anionic (0.1% SDS) and non-ionic (1 and 5% Tween 80 and 1% Triton X-100) surfactants. In addition, the enzyme was relatively stable towards oxidizing agents, retaining more than 79 and 70% of its initial activity after 1 h incubation in the presence of 1% H2O2 and 0.1% sodium perborate, respectively. The enzyme showed excellent stability with a wide range of commercial solid and liquid detergents at 30 and 40 °C. Considering its promising properties, B. mojavensis A21 may find potential application in laundry detergents.  相似文献   

18.
A Gram-stain positive, facultative anaerobic, motile, spore-forming rod-shaped bacterium with peritrichous flagella, designated DX-5T, was isolated from an electroactive biofilm. Growth was observed to occur at 35–60 °C, at pH 7.0–10.0 and with 0.5–10 % (w/v) NaCl (optimum growth: 50 °C, pH 8.0 and 0.5–3 % NaCl). Cells were determined to be catalase- and oxidase-positive. The predominant respiratory quinone was identified as MK-7; the major polar lipids were determined to be diphosphatidylglycerol, phosphatidylglycerol, glycolipid, aminoglycolipid and an unidentified phospholipid; the DNA G+C content was determined to be 46.6 mol%; and the major fatty acids (>5 %) were identified as anteiso-C15:0 (33.6 %), iso-C15:0 (24.1 %) and anteiso-C17:0 (13.4 %). The phylogenetic analysis based on 16S rRNA gene sequence comparisons indicated that strain DX-5T should be assigned to the genus Bacillus, and was related most closely to the type strains of B. fortis DSM 16012T (96.3 %), B. composti KACC 16872T (96.3 %) and B. fordii DSM 16014T (95.8 %). Results of phenotypic, chemotaxonomic and genotypic analysis indicated that strain DX-5T represents a novel species, for which the name B. sediminis sp. nov. is proposed. The type strain is DX-5T (=CGMCC 1.12412T = KCTC 33102T).  相似文献   

19.
A novel alkali-tolerant strain JY-2, which could utilize phenol as sole source of carbon and energy, was isolated from activated sludge. It was identified as Pseudomonas sp. by 16S rDNA sequencing analysis. The appropriate conditions for strain growth and phenol biodegradation were as follows: pH 8.0–10.0 and temperature 23–30°C. With initial phenol concentrations of 225, 400, 550 and 750 mg/l, the degradation efficiencies were 94.9, 93.3, 89.3 and 48.2% within 40 h at pH 10.0 and 30°C, respectively. The alkaline phenol-containing wastewater treatment augmented with strain JY-2 in sequencing batch reactor (SBR) system was investigated, which suggested that the bioaugmented (BA) system exhibited the better performance for adjusting high pH to neutral value than the non-bioaugmented (non-BA) one. Also, the BA system showed strong abilities for phenol degradation and maintaining good sedimentation coefficient (SV30). The microbial community dynamics of both sequencing batch reactor (SBR) systems were analyzed by Denaturing Gradient Gel Electrophoresis (DGGE) technique, which showed substantial changes between the two systems. This study suggests that it is feasible to treat alkaline phenol-containing wastewater augmented with strain JY-2.  相似文献   

20.
A halophilic, aerobic bacterium, designated GD01T, was isolated from a mangrove forest soil near the South China Sea. Cells of strain GD01T were Gram staining positive, oxidase positive, and catalase positive. The strain was rod shaped and motile by means of peritrichous flagella and produced ellipsoidal endospores. The strain was able to grow with NaCl at concentrations of 0.5–12 % (optimum 3–5 %, w/v), at temperatures of 20–50 °C (optimum 30 °C), and at pH 6.0–8.5 (optimum pH 7.0). Phylogenetic analysis based on 16S rRNA gene sequences showed that strain GD01T formed a cluster with O. profundus DSM 18246T (96.4 % 16S rRNA gene sequence similarity), O. caeni KCTC 13061T (95.4 %), and O. oncorhynchi JCM 12661T (94.5 %). The G+C content of strain GD01T was 38.7 mol%. The major respiratory quinone was MK-7. The major cellular fatty acids (>5 %) were anteiso-C15:0, iso-C16:0 (13.7 %), anteiso-C17:0 (12.6 %), iso-C15:0 (9.9 %), iso-C14:0 (9.5 %), and C16:0 (5.0 %). The polar lipids consisted of diphosphatidylglycerol, phosphatidylglycerol, glycolipid, four unknown lipids, and four unknown phospholipids. Based on phenotypic characteristics, chemotaxonomic features, and phylogenetic analysis based on 16S rRNA gene sequences, the strain was identified to represent a distinct novel species in the genus Oceanobacillus, and the name proposed is Oceanobacillus halophilum sp. nov. with type train GD01T (=CCTCC AB 2012863T = KCTC 33101T).  相似文献   

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