scholarly journals The pst Operon of Bacillus subtilis Is Specifically Induced by Alkali Stress

2003 ◽  
Vol 185 (16) ◽  
pp. 5019-5022 ◽  
Author(s):  
Akram Atalla ◽  
Wolfgang Schumann
Keyword(s):  
Bacillus Subtilis ◽  
Ph Value ◽  
Alkali Treatment ◽  
Transcriptional Start Site ◽  
Sudden Increase ◽  
Alkali Stress ◽  
Pst Operon ◽  
Northern Blot Experiment ◽  
Transcriptional Fusions ◽  
External Ph

ABSTRACT To cope with a sudden increase in the external pH value to 8.9, Bacillus subtilis cells induce about 80 genes which can be divided into two classes. Most of these genes are members of the σW regulon, while some are under the control of so-far-unknown transcriptional regulators. The genes of the pst operon belong to the second class. Here, we attempted to answer the questions of why and how the genes of this operon are induced. Using transcriptional fusions to two of the five genes of this operon, we confirmed their induction after alkali stress. Furthermore, a Northern blot experiment revealed that the complete operon was alkali inducible, that the transcriptional start site used was identical to that used after phosphate starvation, and that induction was prevented in a phoR background. Most interestingly, increasing the phosphate concentration within the medium prevented alkali induction of the pst operon, and phoA, another member of the PhoRP regulon, did not respond to alkali stress. In the end, we showed that alkali treatment completely prevented phosphate uptake. These results are discussed to explain alkali induction of the pst operon.

scholarly journals Dual Negative Control of spx Transcription Initiation from the P3 Promoter by Repressors PerR and YodB in Bacillus subtilis

2006 ◽  
Vol 189 (5) ◽  
pp. 1736-1744 ◽  
Author(s):  
Montira Leelakriangsak ◽  
Kazuo Kobayashi ◽  
Peter Zuber
Keyword(s):  
Oxidative Stress ◽  
Bacillus Subtilis ◽  
Transcription Initiation ◽  
Transcriptional Start Site ◽  
Regulatory Region ◽  
Point Mutations ◽  
Negative Control ◽  
Response To Treatment ◽  
Additive Increase

ABSTRACT The spx gene encodes an RNA polymerase-binding protein that exerts negative and positive transcriptional control in response to oxidative stress in Bacillus subtilis. It resides in the yjbC-spx operon and is transcribed from at least five promoters located in the yjbC regulatory region or in the yjbC-spx intergenic region. Induction of spx transcription in response to treatment with the thiol-specific oxidant diamide is the result of transcription initiation at the P3 promoter located upstream of the spx coding sequence. Previous studies conducted elsewhere and analyses of transcription factor mutants using transformation array technology have uncovered two transcriptional repressors, PerR and YodB, that target the cis-acting negative control elements of the P3 promoter. Expression of an spx-bgaB fusion carrying the P3 promoter is elevated in a yodB or perR mutant, and an additive increase in expression was observed in a yodB perR double mutant. Primer extension analysis of spx RNA shows the same additive increase in P3 transcript levels in yodB perR mutant cells. Purified YodB and PerR repress spx transcription in vitro when wild-type spx P3 promoter DNA was used as a template. Point mutations at positions within the P3 promoter relieved YodB-dependent repression, while a point mutation at position +24 reduced PerR repression. DNase I footprinting analysis showed that YodB protects a region that includes the P3 −10 and −35 regions, while PerR binds to a region downstream of the P3 transcriptional start site. The binding of both repressors is impaired by the treatment of footprinting reactions with diamide or hydrogen peroxide. The study has uncovered a mechanism of dual negative control that relates to the oxidative stress response of gram-positive bacteria.

Malachite green bioremoval by a newly isolated strain Citrobacter sedlakii RI11; enhancement of the treatment by biosurfactant addition

2015 ◽  
Vol 72 (8) ◽  
pp. 1283-1293 ◽  
Author(s):  
Inès Mnif ◽  
Raouia Fendri ◽  
Dhouha Ghribi
Keyword(s):  
Bacillus Subtilis ◽  
Effective Treatment ◽  
Malachite Green ◽  
Ph Value ◽  
Synthetic Dyes ◽  
Alkaline Ph ◽  
Selective Enrichment ◽  
Decolorization Efficiency ◽  
Higher Doses ◽  
Microbial Surfactant

Citrobacter sedlackii RI11, isolated from acclimated textile effluent after selective enrichment on synthetic dyes, was assessed for malachite green (MG) biotreatment potency. Results indicate that this bacterium has potential for use in effective treatment of MG contaminated wastewaters under shaking conditions at neutral and alkaline pH value, characteristic of typical textile effluents. Also, the newly isolated strain can tolerate higher doses of dye and decolorize up to 1,000 mg/l of dye. When used as microbial surfactant to enhance MG biodecolorization, Bacillus subtilis SPB1-derived lipopeptide accelerated the decolorization rate and maximized the decolorization efficiency at an optimal concentration of biosurfactant of about 0.075%. Studies ensured that MG removal by this strain could be due to biodegradation and/or adsorption. Results on germination potencies of different seeds using the treated dyes under different conditions favor the use of SPB1 biosurfactant for the treatment of MG.

scholarly journals The Purine Efflux Pump PbuE in Bacillus subtilis Modulates Expression of the PurR and G-Box (XptR) Regulons by Adjusting the Purine Base Pool Size

2005 ◽  
Vol 187 (2) ◽  
pp. 791-794 ◽  
Author(s):  
Per Nygaard ◽  
Hans H. Saxild
Keyword(s):  
Bacillus Subtilis ◽  
De Novo ◽  
Efflux Pump ◽  
Purine Base ◽  
Purine Bases ◽  
Purine Analogs ◽  
Expression Of Genes ◽  
Genes Encoding ◽  
Transcriptional Fusions

ABSTRACT In Bacillus subtilis, the expression of genes encoding enzymes and other proteins involved in purine de novo synthesis and salvage is affected by purine bases and phosphoribosylpyrophosphate (PRPP). The transcription of the genes belonging to the PurR regulon is negatively regulated by the PurR protein and PRPP. The expression of the genes belonging to the G-box (XptR) regulon, including the pbuE gene, is negatively regulated by a riboswitch-controlled transcription termination mechanism. The G-box regulon effector molecules are hypoxanthine and guanine. pbuE encodes a purine base efflux pump and is now recognized as belonging to a third purine regulon. The expression of the pbuE gene is positively regulated by a riboswitch that recognizes adenine. Here we show that the expression of pbuE′-lacZ transcriptional fusions are induced by adenine to the highest extent in mutants which do not express a functional PbuE pump. In a mutant defective in the metabolism of adenine, the ade apt mutant, we found a high intracellular level of adenine and constitutive high levels of PbuE. A growth test using a purine auxotroph provided further evidence for the role of PbuE in lowering the intracellular concentration of purine bases, including adenine. Purine analogs also affect the expression of pbuE, which might be of importance for the protection against toxic analogs. In a mutant that overexpresses PbuE, the expression of genes belonging to the PurR regulon was increased. Our findings provide further evidence for important functions of the PbuE protein, such as acting as a pump that lowers the purine base pool and affects the expression of the G-box and PurR regulons, including pbuE itself, and as a pump involved in protection against toxic purine base analogs.

scholarly journals Acid and Base Stress and Transcriptomic Responses in Bacillus subtilis

2008 ◽  
Vol 75 (4) ◽  
pp. 981-990 ◽  
Author(s):  
Jessica C. Wilks ◽  
Ryan D. Kitko ◽  
Sarah H. Cleeton ◽  
Grace E. Lee ◽  
Chinagozi S. Ugwu ◽  
...  
Keyword(s):  
Bacillus Subtilis ◽  
Stress Responses ◽  
Glutamate Synthase ◽  
Luria Broth ◽  
Lag Time ◽  
Open Reading Frames ◽  
High Ph ◽  
Acid And Base ◽  
Time Required ◽  
External Ph

ABSTRACT Acid and base environmental stress responses were investigated in Bacillus subtilis. B. subtilis AG174 cultures in buffered potassium-modified Luria broth were switched from pH 8.5 to pH 6.0 and recovered growth rapidly, whereas cultures switched from pH 6.0 to pH 8.5 showed a long lag time. Log-phase cultures at pH 6.0 survived 60 to 100% at pH 4.5, whereas cells grown at pH 7.0 survived <15%. Cells grown at pH 9.0 survived 40 to 100% at pH 10, whereas cells grown at pH 7.0 survived <5%. Thus, growth in a moderate acid or base induced adaptation to a more extreme acid or base, respectively. Expression indices from Affymetrix chip hybridization were obtained for 4,095 protein-encoding open reading frames of B. subtilis grown at external pH 6, pH 7, and pH 9. Growth at pH 6 upregulated acetoin production (alsDS), dehydrogenases (adhA, ald, fdhD, and gabD), and decarboxylases (psd and speA). Acid upregulated malate metabolism (maeN), metal export (czcDO and cadA), oxidative stress (catalase katA; OYE family namA), and the SigX extracytoplasmic stress regulon. Growth at pH 9 upregulated arginine catabolism (roc), which generates organic acids, glutamate synthase (gltAB), polyamine acetylation and transport (blt), the K+/H+ antiporter (yhaTU), and cytochrome oxidoreductases (cyd, ctaACE, and qcrC). The SigH, SigL, and SigW regulons were upregulated at high pH. Overall, greater genetic adaptation was seen at pH 9 than at pH 6, which may explain the lag time required for growth shift to high pH. Low external pH favored dehydrogenases and decarboxylases that may consume acids and generate basic amines, whereas high external pH favored catabolism-generating acids.

scholarly journals PENGARUH LAMA FERMENTASI OLEH Bacillus subtilis TERHADAP KARAKTERISTIK SERE KEDELE

2019 ◽  
Vol 8 (3) ◽  
pp. 226
Author(s):  
Sri Madiarti Sipayung ◽  
I Wayan Rai Widarta ◽  
I Desak Putu Kartika Pratiwi
Keyword(s):  
Bacillus Subtilis ◽  
Ph Value ◽  
Total Acid ◽  
Fermentation Time ◽  
Crude Fiber Content ◽  
Randomized Design ◽  
Result Show ◽  
Soybean Fermentation ◽  
Completely Randomized Design ◽  
Normal Taste

This research aims to find out the effect of soybean fermentation time by Bacillus subtilis to produce sere kedele with the best characteristics. This research used completely randomized design (CRD) with one treatment factor of the fermentation time with 5 period of fermentation time (12, 18, 24, 30 and 36h). Each treatment was repeated 3 times, resulted 15 experimental units. The data were then analyzed with Analysis of Variance method and if the treatment had an effect on the variable, followed by the Duncan test. The result show that fermentation times had significant effect to moisture, ash, protein, fat, carbohydrate, crude fiber content, total acid, pH value, the number microbes, hedonic test for taste, scoring test for taste and overall acceptance of sere kedele. Fermented by B. subtilis for 12h resulted in the best characteristic under the following criteria : 58.05% moisture content, 2.39% ash content, 15.79% protein content, 14.39% fat contetnt, 9,38% carbohydrate content, 6.1 pH value, 0.11% total acid, 9.59log cfu/g the number microbes, color, flavour, texture liked, normal taste with sour taste and overall acceptance liked.   Keyword : soybean, sere kedele, Bacillus subtilis, fermentation, traditional food .

A β-Mannanase from Bacillus subtilis B36: Purification, Properties, Sequencing, Gene Cloning and Expression in Escherichia coli

2006 ◽  
Vol 61 (11-12) ◽  
pp. 840-846 ◽  
Author(s):  
Ya Nan Li ◽  
Kun Meng ◽  
Ya Ru Wang ◽  
Bin Yao
Keyword(s):  
Escherichia Coli ◽  
Enzyme Activity ◽  
Bacillus Subtilis ◽  
Specific Activity ◽  
Ph Value ◽  
High Specificity ◽  
Apparent Molecular Weight ◽  
Cloning And Expression ◽  
Gene Cloning And Expression ◽  
Reading Frame

Abstract MANB36, a secrete endo-β-1,4-D-mannanase produced by Bacillus subtilis B36, was puri­fied to homogeneity from a culture supernatant and characterized. The optimum pH value for the mannanase activity of MANB36 is 6.4 and the optimum temperature is 50 °C. The enzyme activity of MANB36 is remarkably thermostable at 60 °C and the specific activity of MANB36 is 927.84 U/mg. Metal cations (except Hg2+ and Ag+), EDTA and 2-mercaptoetha- nol (2-ME) have no effects on enzyme activity. This enzyme exhibits high specificity with the substituted galactomannan locust bean gum (LBG). The gene encoding for MANB36, manB36, was cloned by PCR and sequenced. manB36 contains a single open reading frame (ORF) consisting of 1104 bp that encodes a protein of 367 amino acids. The predicted mo­lecular weight of 38.13 kDa, calculated by the deduced protein of the gene manB36 without signal peptide, coincides with the apparent molecular weight of 38.0 kDa of the purified MANB36 estimated by SDS-PAGE. The mature protein of MANB36 has been expressed in Escherichia coli BL21 and the expressed mannanase has normal bioactivity.

Effects of Different Treatments on Surface Activity of Rice Straw Particleboard

2020 ◽  
Vol 12 (2) ◽  
pp. 289-295 ◽  
Author(s):  
Xian-Qing Xiong ◽  
Ying-Ying Yuan ◽  
Yi-Ting Niu ◽  
Liang-Ting Zhang ◽  
Zhi-Hui Wu
Keyword(s):  
Rice Straw ◽  
Surface Activity ◽  
Treatment Time ◽  
Ph Value ◽  
Sodium Hydroxide Solution ◽  
Alkali Treatment ◽  
Surface Absorption ◽  
Bonding Performance ◽  
Absorption Performance ◽  
Corona Treatment

The surface activity of rice straw particleboard (RSP), which has a significant effect on the finishing and bonding performance, is reduced by wax coating and free radicals on the straw fiber. The RSP surface was treated by corona treatment and alkali treatment to reveal the effects of different treatments on the surface activity of RSP. The infiltration height method was applied to evaluate the variation of surface activity. The alkalized samples of RSP with different densities were prepared by using sodium hydroxide solution with pH value of 8∼14. The samples of different densities were then subjected to corona treatment under high purity oxygen conditions with treatment power of 50 W, 100 W, 300 W, and 500 W and with a time of 4 min or 7 min. The surface activity of the treated specimens was evaluated by measuring the absorption properties of three kinds of liquids by infiltration-height method: distilled water, glycerin, and alcohol. The results revealed the following. (1) After alkalization treatment, the surface absorption performance of RSP for these three liquids was improved, and it increased with the increase of pH value of the treatment solution. The suitable pH value of the alkalized solution for RSP is 7∼11, which can improve the surface absorption performance. (2) After corona treatment, the surface absorption performance of RSP increased with the increase of corona treatment power. RSP had the highest surface absorption performance for alcohol. With the density of RSP increased, the surface absorbability slightly decreased. Therefore, it is not suitable to utilize corona treatment in improving absorption for the higher density RSP. At the same time, with the variation of corona treatment time, the absorption of RSP surface changed irregularly because of the polarity of different test liquids. (3) The reasonable parameters of alkalization treatment and corona treatment are beneficial in improving the gluability of RSP. These results have guiding significance for RSP surface decoration process.

The Effects of Alkaline Treatment on Excess Sludge Supernatant Characteristics

2013 ◽  
Vol 361-363 ◽  
pp. 1046-1049 ◽  
Author(s):  
Ting Ting Li ◽  
Zhi Min Fu
Keyword(s):  
Ph Value ◽  
Sodium Hydroxide Solution ◽  
Alkali Treatment ◽  
Oxygen Demand ◽  
Alkaline Treatment ◽  
Maximum Amount ◽  
Batch Experiments ◽  
Excess Sludge ◽  
Initial Ph ◽  
Soluble Chemical Oxygen Demand

The effect of alkali treatment on excess sludge supernatant characteristics was studied in this experiment. 4 mol/L sodium hydroxide solution was utilized to adjust the initial pH value of excess sludge to 9.0, 11.0 and 13.0. Batch experiments were operated in 35 °C shaking bath for 12 h. The soluble chemical oxygen demand (SCOD), protein and polysaccharide concentration in excess sludge supernatant was measured every 3 h. The experimental results showed that maximum amount of protein, polysaccharide and SCOD were obtained when the initial pH value was 13.0.

scholarly journals Identification of phosphate-solubilizing microorganisms and determination of their phosphate-solubilizing activity and growth-promoting capability

BioResources ◽  
2020 ◽  
Vol 15 (2) ◽  
pp. 2560-2578 ◽  
Author(s):  
Ying-Ying Wang ◽  
Pei-Shan Li ◽  
Bi-Xian Zhang ◽  
Yan-Ping Wang ◽  
Jing Meng ◽  
...  
Keyword(s):  
Bacillus Subtilis ◽  
Phosphorus Content ◽  
Ph Value ◽  
Inverse Correlation ◽  
Penicillium Oxalicum ◽  
Fermentation Time ◽  
Soluble Phosphorus ◽  
Growth Promoting ◽  
Phosphate Solubilizing ◽  
Solubilizing Activity

Phosphate-solubilizing microorganisms have been considered as a novel alternative approach to provide phosphate fertilizers that promote plant growth. In this study, three strains were isolated and identified as Penicillium oxalicum FJG21, Penicillium oxalicum FJQ5, and Bacillus subtilis BPM12, with a relatively high phosphate-solubilizing activity. Various phosphate sources were investigated, and Ca3(PO4)2 was identified as the effective phosphate source. Factors governing the phosphate-solubilizing activity of the strains included carbon and nitrogen sources, initial pH, and fermentation time. A high soluble phosphorus content was achieved with 529.0 μg·mL-1, 514.0 μg·mL-1, and 330.7 μg·mL-1 for Penicillium oxalicum FJG21, Penicillium oxalicum FJQ5, and Bacillus subtilis BPM12, respectively. An inverse correlation of the quantity of soluble phosphorus content and the pH value of the medium was observed. In addition, Bacillus subtilis BPM12 displayed a prominent capability of producing indole acetic acid. Penicillium oxalicum FJG21 and Penicillium oxalicum FJQ5 exhibited high cellulase activities. These phosphate-solubilizing microorganisms with good phosphate-solubilizing capability and growth-promoting ability are the promising strains for agricultural utilization.

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