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The gas-phase acidity (GA) of a series of 1,1-bis(trifluoromethanesulfonyl)propane derivatives, Tf2CHCH2CH(R1)R2, and Tf2CHCH2Ar (Ar = ) was determined by measuring proton-transfer equilibria using a Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometer and by computing the free energy of the deprotonated carbanions and the corresponding neutrals. The effects of R1 and R2 or Ar groups on the acidity were examined. In Tf2CHCH2CH(R1)R2, the GA values calculated using the conformers of neutral molecules that are free from the hydrogen-bonding interaction between the acidic hydrogen atom of the Tf2C H moiety and R1 or R2 group and between the hydrogen atom of the C HR1R2 moiety and the SO2CF3 group were correlated in terms of an equation, GA = −17.0ΣσI + 3.4Σσα + 299.5. On the basis of this correlation, it was elucidated that the hydrogen bonding or dipole-dipole interaction in the neutral molecule weakens significantly the acidity. In Tf2CHCH2Ar ( 5, 6 and 7), the GA was strengthened by the strong hydrogen-bonding interaction between the phenolic hydrogen in the aromatic moiety and the SO2CF3 group in the conjugate anion compared with that in the neutral molecule. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Sporulation initiation in Bacillus subtilis is controlled by the phosphorylated form of the master regulator Spo0 A which controls transcription of a multitude of sporulation genes. In this study, we investigated the importance of temporal dynamics of phosphorylated Spo0 A ( Spo0 A∼ P) accumulation by rewiring the network controlling its phosphorylation. We showed that simultaneous induction of KinC, a kinase that can directly phosphorylate Spo0 A, and Spo0 A itself from separately controlled inducible promoters can efficiently trigger sporulation even under nutrient rich conditions. However, the sporulation efficiency in this artificial two-component system was significantly impaired when KinC and/or Spo0 A induction was too high. Using mathematical modelling, we showed that gradual accumulation of Spo0 A∼ P is essential for the proper temporal order of the Spo0 A regulon expression, and that reduction in sporulation efficiency results from the reversal of that order. These insights led us to identify premature repression of DivIVA as one possible explanation for the adverse effects of accelerated accumulation of Spo0 A∼ P on sporulation. Moreover, we found that positive feedback resulting from autoregulation of the native spo0A promoter leads to robust control of Spo0 A∼ P accumulation kinetics. Thus we propose that a major function of the conserved architecture of the sporulation network is controlling Spo0 A activation dynamics. [ABSTRACT FROM AUTHOR]

Fusarium head blight ( FHB) remains a serious problem due to yield loss and mycotoxin accumulation in wheat production worldwide. We previously reported that the closed-flowering (no anther extrusion) characteristic was effective for increasing resistance to FHB infection. In this study, we investigated the relationships between the degree of anther extrusion ( AE) and FHB damage using double haploid lines ( DHLs), derived from F1 plants from crosses between closed-flowering and opened-flowering varieties. These DHLs exhibited various degrees of AE, and the degree of AE was significantly different among DHLs, regardless of the year and environment (pot- or field-grown). FHB severity was the lowest in closed-flowering DHLs, and DHLs with partially extruded anthers showed significantly higher FHB symptoms than those with closed-flowering phenotypes. In general, DHLs with partially extruded anthers also had relatively severe FHB symptoms compared with those exhibiting full anther extrusion. FHB severity was significantly correlated with Fusarium-damaged kernels and deoxynivalenol concentration. The results of this study showed that partially extruded anthers were considered to be a source of FHB infection. The closed-flowering phenotype improved resistance to FHB infection. Meanwhile, phenotypes with rapid anther extrusion and ejection also could contribute to the avoidance of FHB infection. [ABSTRACT FROM AUTHOR]

A trifle of triflyl: N‐substituted anilines react with 1,1,3,3‐tetrakis(triflyl)propane to give a 2,2‐bis(triflyl)ethyl group at the para position of the ring. The product is a zwitterion with a carbanion and an ammonium moiety, and can be used as an acid catalyst for organic reactions (see scheme). [ABSTRACT FROM AUTHOR]

The transcription factor Spo0A is a master regulator for entry into sporulation in the bacterium Bacillus subtilis, but it has been uncertain whether activation of Spo0A is sufficient to trigger development. Spo0A, a member of the response regulator family of gene-control proteins, is activated by phosphorylation via a multicomponent phosphorelay in response to conditions of nutrient limitation. We now report that sporulation can be triggered with high efficiency in cells in the exponential phase of growth in rich medium by artificial induction of the synthesis of any one of three histidine kinases that feed phosphoryl groups into the relay. We further show that the levels of Spo0A protein and activity increase gradually over the first 2 h of sporulation both under conditions of nutrient limitation and in response to induction of kinase synthesis. Evidence indicates that this gradual increase in Spo0A protein and activity plays a critical role in triggering sporulation and requires the action of the phosphorelay. [ABSTRACT FROM AUTHOR]

The master regulator for entry into sporulation in Bacillus subtilis is the response regulator Spo0A, which directly governs the expression of about 121 genes. Using cells in which the synthesis of Spo0A was under the control of an inducible promoter or in which production of the regulatory protein was impaired by a promoter mutation, we found that sporulation required a high (threshold) level of Spo0A and that many genes in the regulon differentially responded to high and low doses of the regulator. We distinguished four categories of genes, as follows: (i) those that required a high level of Spo0A to be activated, (ii) those that required a high level of Spo0A to be repressed, (iii) those that were activated at a low level of the regulator, and (iv) those that were repressed at a low dose of the regulator. Genes that required a high dose of Spo0A to be activated were found to have low binding constants for the DNA-binding protein. Some genes that were turned on at a low dose of Spo0A either had a high binding constant for the regulatory protein or were activated by an indirect mechanism involving Spo0A-mediated relief of repression by the repressor protein AbrB. We propose that progressive increases in the level of Spo0A leads to an early phase of transcription in which genes that play auxiliary roles in development, such as cannibalism and biofilm formation, are turned on and a later phase in which genes that play a direct role in sporulation are activated. [ABSTRACT FROM AUTHOR]

We investigated HutP-dependent transcription antitermination of the Bacillus subtilis hut operon. In vitro transcription assays with the B. subtilis A -containing RNA polymerase indicated that HutP inhibits transcription termination at the internal terminator by binding to the antiterminator on hut mRNA in the presence of histidine. Ethylnitrosourea modification interference assays and mutational analyses of the interference sites showed that interaction of HutP with a region containing three UAG trinucleotide sequences, which is located on top of the antiterminator structure, is critical for hut antitermination in vivo . Results from kinetic analysis of binding of HutP to RNA containing various portions of the antiterminator sequences indicated that secondary structure is required for binding of HutP to the region containing three UAG triplets in the antiterminator. The in vivo HutP antiterminator activity was reduced by the mutations in the N-terminal region of HutP. The HutP variants with H4A, R7A, I9A and Q26A mutations exhibited reduced binding affinities to the antiterminator RNA in vitro . A 25-mer peptide consisting of amino acid residues 2–26 of HutP bound to the antiterminator RNA. These results indicated that the N-terminus of HutP is involved in binding of HutP to the antiterminator RNA. [ABSTRACT FROM AUTHOR]

The master regulator for entry into sporulation in Bacillus subtilis is the DNA-binding protein Spo0A, which has been found to influence, directly or indirectly, the expression of over 500 genes during the early stages of development. To search on a genome-wide basis for genes under the direct control of Spo0A, we used chromatin immunoprecipitation in combination with gene microarray analysis to identify regions of the chromosome at which an activated form of Spo0A binds in vivo. This information in combination with transcriptional profiling using gene microarrays, gel electrophoretic mobility shift assays, using the DNA-binding domain of Spo0A, and bioinformatics enabled us to assign 103 genes to the Spo0A regulon in addition to 18 previously known members. Thus, in total, 121 genes, which are organized as 30 single-gene units and 24 operons, are likely to be under the direct control of Spo0A. Forty of these genes are under the positive control of Spo0A, and 81 are under its negative control. Among newly identified members of the regulon with transcription that was stimulated by Spo0A are genes for metabolic enzymes and genes for efflux pumps. Among members with transcription that was in-hibited by Spo0A are genes encoding components of the DNA replication machinery and genes that govern flagellum biosynthesis and chemotaxis. Also in-cluded in the regulon are many (25) genes with products that are direct or indirect regulators of gene transcription. Spo0A is a master regulator for sporulation, but many of its effects on the global pattern of gene transcription are likely to be mediated indirectly by regulatory genes under its control. [ABSTRACT FROM AUTHOR]

Provides information on a study that reported that Spo0A, a member of the response regulator family of transcription factors, continues to function after the initiation phase of sporulation in the bacterium Bacillus subtilis and that it becomes a cell-specific transcription factor when the sporangium is divided into a mother cell and forespore. Methodology of the study; Results and discussion on the study.

Summary Sporulation in Bacillus subtilis involves the formation of a polar septum, which divides the sporangium into a mother cell and a forespore. The σ E factor, which is encoded within the spoIIG operon, is a cell-specific regulatory protein that directs gene transcription in the mother cell. σ E is synthesized as an inactive proprotein pro-σ E , which is converted to the mature factor by the putative processing enzyme SpoIIGA. Processing of pro-σ E does not commence until after asymmetric division when σ E is largely confined to the mother cell. Processing depends on the signalling protein SpoIIR, which delays proteolysis until after polar septation, but the mechanism by which σ E is confined to the mother cell is not understood. Previous work favoured a model in which pro-σ E localizes to the mother cell face of the polar septum, such that σ E would be selectively released into mother cell cytoplasm. Based on the use of green fluorescent protein (GFP) fusions, we now report that pro-σ E is distributed approximately uniformly along all membrane surfaces and is not confined to the mother- cell face of the septum. Rather, our results are consistent with a model in which preferential and persistent transcription of the spoIIG operon in the mother cell and degradation of σ E in the forespore contribute to the selective accumulation of σ E in the mother cell. Persistent transcription of spoIIG after polar septation also contributes to the proper timing of pro-σ E processing. [ABSTRACT FROM AUTHOR]

The patient was a 62-year-old man with atrial fibrillation and severe scoliosis. Scoliosis may impair cardiorespiratory function. Enhanced computed tomography (CT) was helpful for the Brockenbrough method. Three-dimensional (3D) mapping also demonstrated clockwise rotation of the heart. We successfully isolated extensive encircling pulmonary vein in this patient using enhanced CT and 3D mapping. The CT venous images revealed appropriate localization of the vein and heart. CT and 3D mapping may ensure a more stable and safer procedure. [ABSTRACT FROM AUTHOR]