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Induced Transcriptional Expression of Bacillus subtilis Amino Acid Permease yvbW in Response to Leucine Limitation  [PDF]
Sean M. Rollins
Advances in Microbiology (AiM) , 2014, DOI: 10.4236/aim.2014.48053
Abstract:

T box sequences have been identified upstream of a large number of uncharacterized genes such as transporters in bacterial genomes. Expression of each T box family gene is induced by limitation for a specific amino acid. T box family genes contain an untranslated leader region containing a factor-independent transcriptional terminator upstream of the structural genes. The anticodon of uncharged tRNA base-pairs with the leader mRNA at a codon referred to as the specifier sequence, inducing formation of an alternative antiterminator structure, allowing expression of the structural genes. There are several additional conserved primary sequence and secondary structural elements. Analysis of these elements can be used to predict the identity of the specifier codon and the amino acid signal. Bacillus subtilis hypothetical amino acid permease, yvbW, was analyzed as an example of this type of transcriptional regulatory prediction suggesting expression in response to leucine limitation. Expression was induced up to 130-fold in response to leucine limitation, utilizing a yvbW-lacZ transcriptional fusion. These data suggest that hypothetical amino acid permease YvbW may participate in leucine metabolism. A yvbW knockout strain was generated, although the substrate specificity for the putative amino acid permease was not identified.

Transcriptional Regulation of the rsbV Promoter Controlling Stress Responses to Ethanol, Carbon Limitation, and Phosphorous Limitation in Bacillus subtilis  [PDF]
Soo-Keun Choi,Milton H. Saier Jr.
International Journal of Microbiology , 2010, DOI: 10.1155/2010/263410
Abstract: The B-dependent promoter in front of the rsbV gene of Bacillus subtilis is induced ~5-fold in response to (1) the addition of 4% ethanol, (2) carbon starvation, and (3) phosphorous starvation. Binding sites for the global carbon and nitrogen regulators, CcpA and TnrA, were mutated, and the consequences of their loss and that of CcpA or TnrA were studied using rsbV-lacZ fusions. These responses proved to be dependent on CcpA, TnrA, and their putative binding sites upstream of the promoter. Induction in response to glucose limitation was largely abolished by loss of CcpA or the upstream region, while induction in response to phosphorous limitation was largely abolished only by the upstream mutations. The results suggest that CcpA directly influences the carbon starvation response and that both proteins exert indirect effects on all three stress responses. The integrity of the DNA sequence is important for all three responses.
Transcriptional Regulation of the rsbV Promoter Controlling Stress Responses to Ethanol, Carbon Limitation, and Phosphorous Limitation in Bacillus subtilis  [PDF]
Soo-Keun Choi,Milton H. Saier Jr.
International Journal of Microbiology , 2010, DOI: 10.1155/2010/263410
Abstract: The -dependent promoter in front of the rsbV gene of Bacillus subtilis is induced 5-fold in response to (1) the addition of 4% ethanol, (2) carbon starvation, and (3) phosphorous starvation. Binding sites for the global carbon and nitrogen regulators, CcpA and TnrA, were mutated, and the consequences of their loss and that of CcpA or TnrA were studied using rsbV-lacZ fusions. These responses proved to be dependent on CcpA, TnrA, and their putative binding sites upstream of the promoter. Induction in response to glucose limitation was largely abolished by loss of CcpA or the upstream region, while induction in response to phosphorous limitation was largely abolished only by the upstream mutations. The results suggest that CcpA directly influences the carbon starvation response and that both proteins exert indirect effects on all three stress responses. The integrity of the DNA sequence is important for all three responses. 1. Introduction In Gram-positive bacteria such as species of Bacillus, the complex rsb operon encodes the stress sigma factor, σB, and many of its regulatory proteins [1, 2]. This operon includes two promoters, a σA-dependent promoter in front of the rsbR gene at the beginning of the operon, and a σB-dependent promoter in front of the rsbV gene, the fifth gene in this 8-cistron operon [3]. Much is known about the biochemical mechanism of sigma B control which involves an anti-σB, an anti-anti-σB, and protein phosphorylation [4–6]. Additionally, induction of the σBpromoter in part mediates adaptation to heat shock, (40–54 ), cold shock (4–12 ), NaCl (10%) shock, ethanol (4–10%) shock, and various starvation (carbon, phosphorous, and nitrogen) stresses [5, 7]. It has been argued that a drop in ATP levels may trigger σB activation [8]. Elements of this regulatory system are found in a wide range of bacteria which in addition to low and high G?+?C, Gram-positive bacteria include bacteroidetes, cyanobacteria, proteobacteria, and deinococci [2]. We have investigated the dependencies of various stress responses (ethanol stress and limitation for carbon or phosphorous), showing that these responses are dependent on the principal carbon-limitation transcription factor in B. subtilis, CcpA [9–11], as well as the principal nitrogen regulator TnrA [12]. However, we show that point mutations and deletions in the region upstream of the rsbV promoter, within the rsbU gene, largely abolish all of these stress responses. Because these studies were conducted with an rsbV-lacZ fusion reporter system integrated at the amyE locus, we can conclude that RsbU
DEVELOPMENT OF AN INDUCIBLE EXPRESSION AND SECRETION SYSTEM FOR ALKALINE PROTEINASE IN BACILLUS SUBTILIS
枯草杆菌碱性蛋白酶基因诱导表达载体的构建

ZHU Xin-Hua XIE Fang HUANG Jing XING Zhi-Li WU Zi-Rong,
朱欣华
,谢芳,黄静,邢自力,吴自荣

微生物学通报 , 2003,
Abstract: The regulatory region and the signal peptide sequence of the sacB gene has been amplified by PCR using Bacillus subtilis chromosomal DNA as template, and an inducible secretion vector has been developed based on this sequence, which was ligated with Bacillus subtilis alkaline proteinase gene. Transform Bacillus subtilis DB403 with this vector, and the expression of the inserted Bacillus subtilis alkaline proteinase gene can be induced by addition of sucrose into the medium.
Cytoplasmic Acidification and the Benzoate Transcriptome in Bacillus subtilis  [PDF]
Ryan D. Kitko,Rebecca L. Cleeton,Erin I. Armentrout,Grace E. Lee,Ken Noguchi,Melanie B. Berkmen,Brian D. Jones,Joan L. Slonczewski
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0008255
Abstract: Bacillus subtilis encounters a wide range of environmental pH. The bacteria maintain cytoplasmic pH within a narrow range. Response to acid stress is a poorly understood function of external pH and of permeant acids that conduct protons into the cytoplasm.
Effects of the electrolytic treatment on Bacillus subtilis
Tolentino-Bisneto, Rodolfo;Bidoia, Ederio D.;
Brazilian Journal of Microbiology , 2003, DOI: 10.1590/S1517-83822003000500016
Abstract: conventional processes of water disinfection can generate toxic composites. it is the case of the trihalomethanes (carcinogenic) formed in the contact of chlorine with organic substances present in the water. the electrolytic treatment can be a substitute for the chlorination process without the need for addition of chemical substances to the process. the effect of the electrolytic treatment using carbon cathode on the viability of the microorganism bacillus subtilis was tested to determine the death process. by means of electronic microscopy, it was observed that the main cause of the microorganism's death was the cellular lysis due to the electroporation in the cell membrane.
Differential gene expression in Bacillus subtilis  [PDF]
Dagmar Iber,Joanna Clarkson,Michael D Yudkin,Iain D Campbell
Quantitative Biology , 2005,
Abstract: Sporulation in Bacillus subtilis serves as a paradigm for the development of two different cell types (mother cell and prespore) from a single cell. The mechanism by which the two different developmental programs are initiated has been much studied but is not well understood. With the help of existing and new experimental results, a mathematical model has been developed that reproduces all published in vitro experiments and makes new predictions about the properties of the system in vivo.
Biosynthesis of Alpha Amylase by Chemically Treated Mutant of Bacillus subtilis  [PDF]
Ikram-ul-Haq,Shafia Rani,Hamad Ashraf,M. A. Qadeer
Journal of Biological Sciences , 2002,
Abstract: The present study is concerned with the selection of hyper-producer strain of Bacillus subtilis and optimization of the cultural conditions for the production of alpha amylase in shake flask. The UV irradiated strain of Bacillus subtilis was treated with NTG for different intervals of time (5-60 min). One hundred mutant strains were isolated and tested for the production of alpha amylase and Bacillus subtilis GCBCM-25 gave maximum production of enzyme (2210 U/ml). The optimum conditions for the production of alpha amylase were, NaNO3 as nitrogen source, pH 7.5, phosphate buffer as diluent and 4mM CaCl2. The treatment of NTG for 25 min was found to be suitable for the production of best mutant of Bacillus. The production of alpha amylase was significantly increased with the addition of NaNO3 and 4 mM CaCl2 to the fermentation medium.
Isolation and characterization of protease from Bacillus subtilis 1012M15
ELFI SUSANTI
Biodiversitas , 2003,
Abstract: A local strain of Bacillus sp. BAC4, is known to produce penicillin G acylase (PGA) enzyme with relatively high activity. This strain secretes the PGA into the culture medium. However, it has been reported that PGA activity fall and rise during culture, and the activity plummets during storege at –200C, which probably due to usage protease activity of Bacillus sp. BAC4. To study the possible use of Bacillus subtilis 1012M15 as a host cell for cloning the pga gene from Bacillus sp. BAC4, the protease activity of Bacillus subtilis 1012M15 were studied. Protease activity was determined by Horikoshi method. In this experiment, maximum protease activity in Bacillus subtilis 1012M15 culture was obsereved after 8 hours. At this optimum condition, protease activity of Bacillus sp. BAC4 is five time higher than that of Bacillus subtilis 1012M15. This situation promised the possible usage of Bacillus subtilis 1012M15 as a host cell for pga expression. For protease characterization, the bacterial culture had been separated from the cell debris by centrifugation. The filtrate was concentrated by freeze drying, fractionated by ammonium sulphate, dialyzed in selovan tube, and then fractionated by ion exchance chromatography employing DEAE-cellulose. The five peaks resulted indicated the presence of five protease. Based on inhibitor and activator influence analysis, it could be concluded that proteases from Bacillus subtilis 1012M15 contained of serin protease as well as metalloprotease and serin protease mixture.
Association of RNAs with Bacillus subtilis Hfq  [PDF]
Michael Dambach, Irnov Irnov, Wade C. Winkler
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0055156
Abstract: The prevalence and characteristics of small regulatory RNAs (sRNAs) have not been well characterized for Bacillus subtilis, an important model system for Gram-positive bacteria. However, B. subtilis was recently found to synthesize many candidate sRNAs during stationary phase. In the current study, we performed deep sequencing on Hfq-associated RNAs and found that a small subset of sRNAs associates with Hfq, an enigmatic RNA-binding protein that stabilizes sRNAs in Gram-negatives, but whose role is largely unknown in Gram-positive bacteria. We also found that Hfq associated with antisense RNAs, antitoxin transcripts, and many mRNA leaders. Several new candidate sRNAs and mRNA leader regions were also discovered by this analysis. Additionally, mRNA fragments overlapping with start or stop codons associated with Hfq, while, in contrast, relatively few full-length mRNAs were recovered. Deletion of hfq reduced the intracellular abundance of several representative sRNAs, suggesting that B. subtilis Hfq-sRNA interactions may be functionally significant in vivo. In general, we anticipate this catalog of Hfq-associated RNAs to serve as a resource in the functional characterization of Hfq in B. subtilis.
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