An investigation was carried out using rice straw as a low-cost substrate to study the optimization of xylanase production using a newly identified endospore-forming bacterium, Bacillus altitudinis RS3025. The highest xylanase activity was achieved using 2% rice straw (pretreated with 2% NaOH at 100 °C) at pH 7.0, 37 °C temperature, and with 72-h incubation time. Under the optimized conditions, xylanase activity reached 2518.51 U/mL, which was 11.56-fold higher than the activity under the initial conditions using untreated rice straw as substrate. Enzymatic hydrolysis of the rice straw using crude xylanase of B. altitudinis RS3025 demonstrated the hydrolyzation efficiency of the rice straw waste, especially alkaline rice straw. The highest level of released reducing sugars was 149.78 mg/g substrate. The study demonstrated the successful utilization of rice straw waste for high-level xylanase production using B. altitudinis RS3025 and reducing sugar production using low-cost crude enzyme, which has the advantages of reducing the processing cost and environmental concerns associated with rice straw waste management.
- Klíčová slova
- Bacillus altitudinis, Enzymatic hydrolysis, Enzyme production, Rice straw, Xylanase,
- MeSH
- Bacillus * metabolismus MeSH
- celulasa * MeSH
- fermentace MeSH
- hydrolýza MeSH
- rýže (rod) * metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- celulasa * MeSH
Polyglutamic acid (PGA), a protein in the mucilage of PGA-producing Bacillus spp., has expected applications in medical and biotechnological industries. Although the Bacillaceae family contains over 100 genera, research on bacterial PGA has exclusively focused on the genus Bacillus, especially B. subtilis var. natto and B. licheniformis. In the present study, indigenous Bacillaceae family strains were isolated from withered leaves and soil samples and screened for PGA production. As a result of the screening, the strain 8h was found to produce a mucilage possessing greater viscosity than PGA of B. subtilis var. natto (natto PGA). Biochemical analyses revealed that the 8h mucilage contains 63% protein and 37% polysaccharide, while mucilage of B. subtilis var. natto is composed of 61% protein and 39% polysaccharide. The most plentiful amino acid in 8h mucilage protein was glutamate (43%, mol/mol), which is similar to that of natto PGA, suggesting that it possesses characteristics of PGA. Although natto mucilage contains fructan, glucan was found as the polysaccharide of 8h mucilage. While phylogenetic studies indicated that the strain 8h belongs to Peribacillus simplex, the yield of the viscous mucilage by strain 8h was significantly higher than P. simplex type strain, suggesting that 8h is a mucilage-overproducing strain of P. simplex. Interestingly, 8h mucilage protein was found to contain more hydrophobic amino acid residues than natto PGA, suggesting that its amphiphilicity is suitable as a drug carrier and adjuvant. The present study is the first report of viscous mucilage and PGA-like protein produced by the genus Peribacillus.
- Klíčová slova
- Bacillaceae, Mucilage protein, Peribacillus simplex, Polyglutamic acid, Soil bacteria,
- MeSH
- Bacillus subtilis metabolismus MeSH
- Bacillus * metabolismus MeSH
- fylogeneze MeSH
- kyselina polyglutamová * analýza metabolismus MeSH
- polysacharidy metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- kyselina polyglutamová * MeSH
- polysacharidy MeSH
Polyhydroxyalkanoates (PHAs) are widely used in medical and potentially in other applications due to their biocompatibility and biodegradability. Understanding PHA biosynthetic pathways may lead to the detection of appropriate conditions (substrates) for producing a particular PHA type by a specific microbial strain. The aim of this study was to establish a method enabling potentially interesting PHA bacterial producers to be found. In the study, all four classes of PHA synthases and other genes involved in PHA formation (fabG, phaA, phaB, phaG, and phaJ) were detected by PCR in 64 bacterial collection strains and food isolates. Acinetobacter, Bacillus, Cupriavidus, Escherichia, Klebsiella, Lelliottia, Lysinibacillus, Mammaliicoccus, Oceanobacillus, Pantoea, Peribacillus, Priestia, Pseudomonas, Rahnella, Staphylococcus, and Stenotrophomonas genera were found among these strains. Fructose, glucose, sunflower oil, and propionic acid were utilized as carbon sources and PHA production was detected by Sudan black staining, Nile blue staining, and FTIR methods. The class I synthase and phaA genes were the most frequently found, indicating the strains' ability to synthesize PHA from carbohydrates. Among the tested bacterial strains, the Pseudomonas genus was identified as able to utilize all tested carbon sources. The Pseudomonas extremorientalis strain was determined as a prospect for biotechnology applications.
- Klíčová slova
- bacterial strains, biomaterial, biosynthetic pathways, polyhydroxyalkanoate, screening,
- MeSH
- acyltransferasy genetika metabolismus MeSH
- Bacillus * metabolismus MeSH
- Bacteria metabolismus MeSH
- polyhydroxyalkanoáty * MeSH
- uhlík metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- acyltransferasy MeSH
- polyhydroxyalkanoáty * MeSH
- uhlík MeSH
Longstanding industrial deposits of 1-chloro-4-[2,2,2-trichloro-1-(4-chlorophenyl)ethyl]benzene (DDT) impose environmental threat in Salamanca city, located in central Mexico. Native bacteria from this location were isolated and identified, and their potential utility for DDT biodegradation was examined. Twenty-five isolates were obtained, and cell lysates were analyzed by matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS) with BiotyperTR; twenty-one organisms were identified at species level, and the other four were assigned to genus. The most abundant species corresponded to Bacillus (44%) and Pseudomonas genera (20%). Eight bacteria could grow in the presence of 200 mg/L of DDT. Two-week exposure of Lysinibacillus fusiformis, Bacillus mycoides, Bacillus pumilus, and Bacillus cereus to DDT 50 mg/L and 200 mg/L, caused percentage pesticide degradation in the range 41-48% and 26-31%, respectively. Other four bacteria presented lower degradation rates. Gas chromatography-mass spectrometry (GC-MS) analysis of the spent media revealed that eight isolates assisted the conversion of DDT, DDD (1,1-dichloro-2,2-bis-(4-chlorophenyl)ethane), and DDE (1,1-dichloro-2,2-bis-(4-chlorophenyl)ethylene) to DDMU (1,1-(2-chloro-1,1-ethenediyl)-bis-(4-chlorobenzene)); however, DDNU (2,2-bis(4-chlorophenyl)ethylene), DBP (4,4'-dichlorobenzophenone(bis(4-chlorophenyl)methanone)) and DBH (bis(4-chlorophenyl)methanol) were found only for L. fusiformis, B. mycoides, B. cereus, B. marisflavi, and B. megaterium. Within the context of DDT biodegradation, the first three were the most promising isolates and further studies will be aimed at setting the experimental conditions for efficient mineralization of DDT congeners.
- MeSH
- Bacillaceae * izolace a purifikace metabolismus MeSH
- Bacillus * izolace a purifikace metabolismus MeSH
- Bacteria * chemie klasifikace MeSH
- biodegradace MeSH
- DDT * metabolismus MeSH
- hmotnostní spektrometrie * MeSH
- látky znečišťující životní prostředí metabolismus MeSH
- mikrobiologie životního prostředí * MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Mexiko MeSH
- Názvy látek
- DDT * MeSH
- látky znečišťující životní prostředí MeSH
Mineral nutrition of crop plants is one of the major challenges faced by modern agriculture, particularly in arid and semi-arid regions. In alkaline calcareous soils, the availability of phosphorus and zinc is critically less due to their fixation and precipitation as complexes. Farmers use fertilizers to fulfill crop requirements, but their efficacy is less, which increases production costs. Plant growth-promoting rhizobacteria (PGPR) can improve the availability of crop nutrients through solubilizing the insoluble compounds of phosphorus and zinc in soil. In the present study, a total of 40 rhizobacterial isolates were isolated from cotton rhizosphere and screened for improving cotton growth through the solubilization of phosphorus and zinc. Out of these 40 isolates, seven isolates (IA2, IA3, IA6, IA7, IA8, IA13, and IA14) efficiently solubilized insoluble rock phosphate while seven isolates (IA10, IA16, IA20, IA23, IA24, IA28, and IA30) were more efficient in solubilizing insoluble zinc oxide. In liquid media, strain IA7 (2.75 μg/mL) solubilized the highest amount of phosphate while the highest concentration of soluble zinc was observed in the broth inoculated with strain IA20 (3.94 μg/mL). Seven phosphate-solubilizing and seven zinc-solubilizing strains were evaluated using jar trial to improve the growth of cotton seedlings, and the results were quite promising. All the inoculated treatments showed improvement in growth parameters in comparison with control. Best results were shown by the combined application of IA6 and IA16, followed by the combination of strains IA7 and IA20. Based on the jar trial, the selected isolates were further characterized by plant growth-promoting characters such as siderophores production, HCN production, ammonia production, and exopolysaccharides production. These strains were identified through 16S rRNA sequencing as Bacillus subtilis IA6 (accession # MN005922), Paenibacillus polymyxa IA7 (accession # MN005923), Bacillus sp. IA16 (accession # MN005924), and Bacillus aryabhattai IA20 (accession # MN005925). It is hence concluded that the integrated use of phosphate-solubilizing and zinc-solubilizing strains as potential inoculants can be a promising approach for improving cotton growth under semi-arid conditions.
- MeSH
- Bacillus klasifikace genetika izolace a purifikace metabolismus MeSH
- fosfáty metabolismus MeSH
- fosfor metabolismus MeSH
- fylogeneze MeSH
- Gossypium růst a vývoj mikrobiologie MeSH
- očkovadla agrotechnická klasifikace genetika izolace a purifikace metabolismus MeSH
- Paenibacillus polymyxa klasifikace genetika izolace a purifikace metabolismus MeSH
- půda chemie MeSH
- půdní mikrobiologie MeSH
- rhizosféra MeSH
- RNA ribozomální 16S genetika MeSH
- zinek metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- fosfáty MeSH
- fosfor MeSH
- půda MeSH
- RNA ribozomální 16S MeSH
- zinek MeSH
Microbial and enzymatic degradation of keratin waste is more preferred over various conventional approaches which are costly and not environmentally suitable. Diverse niches are auspicious for the discovery of new microorganisms. To discover novel keratinolytic bacteria, 60 isolates from different poultry dumping sites were initially screened, and among these found a potent keratinolytic isolate (NKSP-7) that displayed higher feather-degrading ability. The selected isolate was identified as Bacillus sp. NKSP-7 based on 16S rDNA sequencing as well as physiochemical and morphological characteristics. The strain NKSP-7 showed complete hydrolysis of native chicken feathers (10 g/L) in nutrient medium after 24 h of incubation at 37 °C under agitation (150 rev/min) and produced thermostable extracellular keratinase. The crude enzyme displayed maximal keratinolytic activity (34.7 U/mL) in phosphate buffer of pH 7.0, and at 60 °C using keratin azure as a substrate. Keratinolytic enzyme showed stability at 20-65 °C for 4 h over the pH range of 5.5-8.0. No obvious inhibitory influence was perceived by cations, organic solvents, EDTA, and detergents. Whereas, enzyme activity was enhanced by adding β-mercaptoethanol, Na+, Cd2+, and Mn2+. All these notable features of keratinase make it a promising candidate for various industrial applications especially for dehairing process in leather industry, bioconversion of poultry waste, and in detergents formulations.
- MeSH
- Bacillus klasifikace genetika izolace a purifikace metabolismus MeSH
- bakteriální proteiny chemie genetika metabolismus MeSH
- biodegradace MeSH
- drůbež * MeSH
- fermentace MeSH
- keratiny analýza metabolismus MeSH
- koncentrace vodíkových iontů MeSH
- kur domácí MeSH
- molekulová hmotnost MeSH
- odpadky - odstraňování metody MeSH
- peří chemie metabolismus MeSH
- proteasy chemie genetika metabolismus MeSH
- proteolýza MeSH
- RNA ribozomální 16S genetika MeSH
- teplota MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- bakteriální proteiny MeSH
- keratinase MeSH Prohlížeč
- keratiny MeSH
- proteasy MeSH
- RNA ribozomální 16S MeSH
Pectinase is widely used in numerous industrial fields, including the food, wine, and paper industries. In this work, seven bacteria were isolated from orange peel and their pectinase production activity was assayed. One bacterium (OR-B2) identified as a Bacillus sp. showed the highest enzyme activity towards others. A gene encoding a pectate lyase designed as PelB-B2 in this work was amplified and heterogeneous expressed in E.coli. PelB-B2 was defined as a member of the PelB pectate lyase family after phylogenic tree analysis. 3D model of PelB-B2 was constructed by SWISS-MODEL and PelB-B2 showed conserved para-β structure. After inducing culture and purified by Ni-affinity chromatography, the properties of the purified PelB-B2 were assayed. Optimal pH and temperature for PelB-B2 was pH 8.0 and 50 °C, respectively. PelB-B2 showed excellent pH stability and thermostability. It was stable within pH range 3.0-11.0 and retained more than 51% activity after incubation at 40 °C, 50 °C, or 60 °C for 1 h. Furthermore, we determined that PelB-B2 was a Ca2+-dependent pectinase and the pectin extracted from citrus was the benefit substrate for PelB-B2. The Km and Vmax of PelB-B2 were 1.64 g/L and 232.56 mol/(L min), respectively. The OR-B2 can be a new resource for pectinase production and the PelB-B2 has potential for industrial application. 7 bacteria were isolated from orange peel, namely OR-B1 to OR-B7 and their pectinase activities were assayed. One pectate lyase belongs to PelB family was cloned from OR-B2 and heterogeneous expressed in E. coli. Purified PelB-B2 was further studied with its properties. Effects of pH, temperature, chemicals, substrate on the enzyme activity were assayed and the enzyme kinetic was also measured.
- Klíčová slova
- Bacillus sp., Enzyme properties, Heterologous expression, Pectate lyase, PelB,
- MeSH
- Bacillus enzymologie genetika metabolismus MeSH
- Citrus metabolismus MeSH
- Escherichia coli genetika metabolismus MeSH
- kinetika MeSH
- koncentrace vodíkových iontů MeSH
- pektiny metabolismus MeSH
- polygalakturonasa biosyntéza metabolismus MeSH
- polysacharid-lyasy metabolismus MeSH
- teplota MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- pectate lyase MeSH Prohlížeč
- pektiny MeSH
- polygalakturonasa MeSH
- polysacharid-lyasy MeSH
Endo-glucanase (cellulase) and xylanase have high industrial demand due to their vast application in industrial processes. This study reports statistical based experimental optimization for co-production of endo-glucanase and xylanase from Bacillus sonorensis BD92. Response surface methodology (RSM) involving central composite design (CCD) with full factorial experiments (23) was applied to elucidate the components that significantly affect co-production of endo-glucanase and xylanase. The optimum co-production conditions for endo-glucanase and xylanase were as follows: carboxymethyl cellulose (CMC) 20 g/L, yeast extract 15 g/L, and time 72 h. The maximum endo-glucanase and xylanase production obtained was 1.46 and 5.69 U/mL, respectively, while the minimum endo-glucanase and xylanase production obtained was 0.66 and 0.25 U/mL, respectively. This statistical model was efficient because only 20 experimental runs were necessary to assess the highest production conditions, and the model accuracy was very satisfactory as coefficient of determination (R2) was 0.95 and 0.89 for endo-glucanase and xylanase, respectively. Further, potential application of these enzymes for saccharification of lignocellulosic biomass (wheat bran, wheat straw, rice straw, and cotton stalk) was also investigated. The results revealed that the biomass was susceptible to enzymatic saccharification and the amount of reducing sugars (glucose and xylose) increased with increase in incubation time. In conclusion, Bacillus sonorensis BD92 reveals a promise as a source of potential endo-glucanase and xylanase producer that could be useful for degrading plant biomass into value-added products of economic importance using precise statistically optimized conditions.
- MeSH
- Bacillus růst a vývoj metabolismus MeSH
- biomasa * MeSH
- celulasa biosyntéza MeSH
- endo-1,4-beta-xylanasy biosyntéza MeSH
- fermentace MeSH
- hydrolýza MeSH
- průmyslová mikrobiologie metody MeSH
- rýže (rod) metabolismus MeSH
- sodná sůl karboxymethylcelulosy MeSH
- statistické modely MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- celulasa MeSH
- endo-1,4-beta-xylanasy MeSH
- sodná sůl karboxymethylcelulosy MeSH
A glycoside hydrolase family 5 β-mannanase-encoding gene was cloned from Bacillus sp. HJ14 isolated from saline soil in Heijing town. Coding sequence of mature protein (without the predicted signal peptide from M1 to A30) was successfully expressed in Escherichia coli BL21 (DE3). Purified recombinant mannanase (rMan5HJ14) exhibited optimal activity at pH 6.5 and 65 °C. The enzyme showed good salt tolerance, retaining more than 56 % β-mannanase activity at 3.0-30.0 % (w/v) NaCl and more than 94 % of the initial activity after incubation with 3.0-30.0 % (w/v) NaCl at 37 °C for 60 min. Almost no mannanase activity was lost after incubation of rMan5HJ14 with trypsin, proteinase K, and Alcalase at 37 °C for 60 min. Surfactants and chelating agents, namely SDS, CTAB, Tween 80, Triton X-100, EDTA, and sodium tripolyphosphate, showed little or no effect (retaining >82.4 % activity) on enzymatic activity. Liquid detergents, namely Tupperware, Walch, Bluemoon, Tide, and OMO, also showed little or no effect (retaining >72.4 % activity) on enzymatic activity at 0.5-2.0 % (v/v). The enzyme further presents a high proportion (11.97 %) of acidic amino acid residues (D and E), which may affect the SDS and NaCl tolerance of the enzyme. Together, the mannanase may be an alternative for potential use in liquid detergent industry.
- MeSH
- aktivace enzymů účinky léků MeSH
- Bacillus účinky léků genetika metabolismus MeSH
- beta-mannosidasa chemie genetika izolace a purifikace metabolismus MeSH
- chlorid sodný farmakologie MeSH
- detergenty farmakologie MeSH
- endopeptidasy metabolismus MeSH
- exprese genu MeSH
- genom bakteriální MeSH
- hydrolýza MeSH
- ionty MeSH
- kovy MeSH
- povrchově aktivní látky farmakologie MeSH
- rekombinantní proteiny MeSH
- sekvence aminokyselin MeSH
- sekvenční analýza DNA MeSH
- stabilita enzymů účinky léků MeSH
- tolerance k soli * MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- beta-mannosidasa MeSH
- chlorid sodný MeSH
- detergenty MeSH
- endopeptidasy MeSH
- ionty MeSH
- kovy MeSH
- povrchově aktivní látky MeSH
- rekombinantní proteiny MeSH
The Bacillus cereus sensu lato group includes potentially pathogenic bacteria that are ubiquitous in the environment and, importantly, could also be present in food products. This study focuses on emetic isolates which presumably could cause acute food poisoning and emetic syndrome. Here, we evaluate the ability of psychrotolerant Bacillus weihenstephanensis MC118 (isolated from soil) and mesophilic B. cereus BOD3/9 isolated from milk to germinate and multiply at 7 and 30 °C. Whereas the rates of germination at 30 °C in milk and nutrient broth of MC118 and BOD3/9 were similar, MC118, but not BOD3/9, proliferated to achieve relatively high numbers (∼10(6) colony-forming units/g) within 7 days of incubation at 7 °C. Mesophilic BOD3/9 showed a slight decrease of cell concentration in similar studies at 7 °C. Genotyping with repetitive extragenic palindromic sequence-based PCR and pulsed field gel electrophoresis revealed significant similarities between BOD3/9 and emetic reference B. cereus F4810/72 strain, while the B. weihenstephanensis MC118 isolate was more similar to the B. weihenstephanensis non-emetic reference DSMZ11821 strain. Our data suggest that emetic isolates that are also psychrotolerant, such as MC118, could constitute a hazard in the dairy industry, where milk could be a suitable medium for germination and growth.
- MeSH
- Bacillus klasifikace genetika růst a vývoj metabolismus MeSH
- časové faktory MeSH
- emetika metabolismus MeSH
- mléko mikrobiologie MeSH
- molekulární typizace MeSH
- polymerázová řetězová reakce MeSH
- pulzní gelová elektroforéza MeSH
- teplota MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- emetika MeSH
