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Journal of Applied Microbiology Sep 2014To compare the germination of laboratory and wild strains of Bacillus subtilis.
AIMS
To compare the germination of laboratory and wild strains of Bacillus subtilis.
METHODS AND RESULTS
The spore germination of B. subtilis 168 (subsp. subtilis) was compared with that of the laboratory strain W23 (subsp. spizizenii) and desert-sourced isolates, including one member of subsp. subtilis (RO-NN-1), strains TU-B-10, RO-E-2, N10 and DV1-B-1, (all subsp. spizizenii), the B. mojavensis strain RO-H-1 and a B. subtilis natto strain. All germinated in L-alanine, although some were slower, and some 10-fold less sensitive to germinant. All germinated in calcium dipicolinate (CaDPA). Germination in asparagine, glucose, fructose + KCl was slow and incomplete in many of the strains, and decoating RO-NN-1 and W23 spores did not restore germination rates. Comparing the sequences of B. subtilis strains 168, RO-NN-1, W23, TU-B-10 and DV1-B-1, the operons encoding GerA, B and K germinant receptors were intact, although the two additional operons yndDEF and yfkQRST had suffered deletions or were absent in several spizizenii strains.
CONCLUSIONS
Wild strains possess an efficient germination machinery for L-alanine germination. AGFK germination is often less efficient, the gerB genes more diverged, and the two germinant receptor operons of unknown function have been lost from the genome in many subsp. spizizenii strains.
SIGNIFICANCE AND IMPACT OF THE STUDY
The two major subspecies of B. subtilis have conserved GerA receptor function, confirming its importance, at least in the natural environments of these strains.
Topics: Alanine; Bacillus subtilis; Bacterial Proteins; Operon; Receptors, Cell Surface; Spores, Bacterial
PubMed: 24916603
DOI: 10.1111/jam.12566 -
Communications Biology Apr 2021Microbes commonly display great genetic plasticity, which has allowed them to colonize all ecological niches on Earth. Bacillus subtilis is a soil-dwelling organism that...
Microbes commonly display great genetic plasticity, which has allowed them to colonize all ecological niches on Earth. Bacillus subtilis is a soil-dwelling organism that can be isolated from a wide variety of environments. An interesting characteristic of this bacterium is its ability to form biofilms that display complex heterogeneity: individual, clonal cells develop diverse phenotypes in response to different environmental conditions within the biofilm. Here, we scrutinized the impact that the number and variety of the Rap-Phr family of regulators and cell-cell communication modules of B. subtilis has on genetic adaptation and evolution. We examine how the Rap family of phosphatase regulators impacts sporulation in diverse niches using a library of single and double rap-phr mutants in competition under 4 distinct growth conditions. Using specific DNA barcodes and whole-genome sequencing, population dynamics were followed, revealing the impact of individual Rap phosphatases and arising mutations on the adaptability of B. subtilis.
Topics: Adaptation, Physiological; Bacillus subtilis; Gene Expression Regulation, Bacterial; Genes, Bacterial; Multigene Family; Phosphoric Monoester Hydrolases; Quorum Sensing
PubMed: 33850233
DOI: 10.1038/s42003-021-01983-9 -
Proceedings of the National Academy of... Feb 2013Wrinkled morphology is a distinctive phenotype observed in mature biofilms produced by a great number of bacteria. Here we study the formation of macroscopic structures...
Wrinkled morphology is a distinctive phenotype observed in mature biofilms produced by a great number of bacteria. Here we study the formation of macroscopic structures (wrinkles and folds) observed during the maturation of Bacillus subtilis pellicles in relation to their mechanical response. We show how the mechanical buckling instability can explain their formation. By performing simple tests, we highlight the role of confining geometry and growth in determining the symmetry of wrinkles. We also experimentally demonstrate that the pellicles are soft elastic materials for small deformations induced by a tensile device. The wrinkled structures are then described by using the equations of elastic plates, which include the growth process as a simple parameter representing biomass production. This growth controls buckling instability, which triggers the formation of wrinkles. We also describe how the structure of ripples is modified when capillary effects are dominant. Finally, the experiments performed on a mutant strain indicate that the presence of an extracellular matrix is required to maintain a connective and elastic pellicle.
Topics: Bacillus subtilis; Biofilms; Biomechanical Phenomena; Elasticity; Mathematical Concepts; Models, Biological; Phenotype
PubMed: 23341623
DOI: 10.1073/pnas.1217178110 -
Molecules (Basel, Switzerland) Sep 2020Chlorogenic acid (CGA), a natural phenolic compound, is an important bioactive compound, and its antibacterial activity has been widely concerned, but its antibacterial...
Chlorogenic acid (CGA), a natural phenolic compound, is an important bioactive compound, and its antibacterial activity has been widely concerned, but its antibacterial mechanism remains largely unknown. Protein leakage and the solution exosmosis conductivity of () reportedly display no noticeable differences before and after CGA treatment. The bacterial cells treated with CGA displayed a consistently smooth surface under the electron microscope, indicating that CGA cannot directly disrupt bacterial membranes. However, CGA induced a significant decrease in the intracellular adenosine triphosphate (ATP) concentration, possibly by affecting the material and energy metabolism or cell-signaling transduction. Furthermore, metabolomic results indicated that CGA stress had a bacteriostatic effect by inducing the intracellular metabolic imbalance of the tricarboxylic acid (TCA) cycle and glycolysis, leading to metabolic disorder and death of . These findings improve the understanding of the complex action mechanisms of CGA antimicrobial activity and provide theoretical support for the application of CGA as a natural antibacterial agent.
Topics: Amino Acids; Bacillus subtilis; Chlorogenic Acid; Intracellular Space; Metabolome; Metabolomics; Microbial Sensitivity Tests; Principal Component Analysis
PubMed: 32899667
DOI: 10.3390/molecules25184038 -
Molecular Microbiology Jul 2012Glutamate, the major amino group donor in anabolism, is synthesized by the combined action of the glutamine synthetase (GS) and the glutamate synthase (GOGAT) in... (Review)
Review
Glutamate, the major amino group donor in anabolism, is synthesized by the combined action of the glutamine synthetase (GS) and the glutamate synthase (GOGAT) in Bacillus subtilis. The glutamate dehydrogenase (GDH) exclusively degrades glutamate. GS and GDH are both trigger enzymes, active in nitrogen metabolism and in controlling gene expression. Feedback-inhibited GS (FBI-GS) controls DNA-binding activities of two transcription factors, the repressor GlnR and TnrA, the global regulator of nitrogen metabolism. FBI-GS binds to and activates GlnR. This protein complex inhibits GS formation and thus glutamine synthesis. Moreover, FBI-GS inhibits DNA-binding activity of TnrA. Glutamate biosynthesis, the reaction linking carbon with nitrogen metabolism, is controlled by GDH. Together with glutamate GDH inhibits GltC, the transcription factor that activates expression of the GOGAT genes. Thus, GS and GDH control glutamine and glutamate synthesis, respectively, depending on the nitrogen status of the cell. B. subtilis lacking a functional GDH show a severe growth defect. Interestingly, the growth defect is suppressed by the rapid activation of an inactive GDH. Thus, maintenance of glutamate homeostasis is crucial for cellular vitality. This review covers the recent work on the complex control of glutamine and glutamate metabolism in the Gram-positive model organism B. subtilis.
Topics: Bacillus subtilis; Gene Expression Regulation, Bacterial; Gene Expression Regulation, Enzymologic; Glutamic Acid; Homeostasis; Metabolic Networks and Pathways; Models, Biological; Quaternary Ammonium Compounds
PubMed: 22625175
DOI: 10.1111/j.1365-2958.2012.08105.x -
Journal of Microbiology and... Jan 2018Biosurfactants or microbial surfactants are surface-active biomolecules that are produced by a variety of microorganisms. Biodegradability and low toxicity have led to...
Biosurfactants or microbial surfactants are surface-active biomolecules that are produced by a variety of microorganisms. Biodegradability and low toxicity have led to the intensification of scientific studies on a wide range of industrial applications for biosurfactants in the field of environmental bioremediation as well as the petroleum industry and enhanced oil recovery. However, the major issues in biosurfactant production are high production cost and low yield. Improving the bioindustrial production processes relies on many strategies, such as the use of cheap raw materials, the optimization of medium-culture conditions, and selecting hyperproducing strains. The present work aims to obtain a mutant with higher biosurfactant production through applying mutagenesis on SPB1 using a combination of UV irradiation and nitrous acid treatment. Following mutagenesis and screening on blood agar and subsequent formation of halos, the mutated strains were examined for emulsifying activity of their culture broth. A mutant designated M2 was selected as it produced biosurfactant at twice higher concentration than the parent strain. The potential of this biosurfactant for industrial uses was shown by studying its stability to environmental stresses such as pH and temperature and its applicability in the oil recovery process. It was practically stable at high temperature and at a wide range of pH, and it recovered above 90% of motor oil adsorbed to a sand sample.
Topics: Bacillus subtilis; Fermentation; Hydrogen-Ion Concentration; Industrial Microbiology; Metabolic Engineering; Mutagenesis; Nitrous Acid; Oil and Gas Industry; Surface-Active Agents; Temperature; Ultraviolet Rays
PubMed: 28750507
DOI: 10.4014/jmb.1701.01033 -
MBio 2011The assembly of the cell division machinery at midcell is a critical step of cytokinesis. Many rod-shaped bacteria position septa using nucleoid occlusion, which...
UNLABELLED
The assembly of the cell division machinery at midcell is a critical step of cytokinesis. Many rod-shaped bacteria position septa using nucleoid occlusion, which prevents division over the chromosome, and the Min system, which prevents division near the poles. Here we examined the in vivo assembly of the Bacillus subtilis MinCD targeting proteins DivIVA, a peripheral membrane protein that preferentially localizes to negatively curved membranes and resembles eukaryotic tropomyosins, and MinJ, which recruits MinCD to DivIVA. We used structured illumination microscopy to demonstrate that both DivIVA and MinJ localize as double rings that flank the septum and first appear early in septal biosynthesis. The subsequent recruitment of MinCD to these double rings would separate the Min proteins from their target, FtsZ, spatially regulating Min activity and allowing continued cell division. Curvature-based localization would also provide temporal regulation, since DivIVA and the Min proteins would localize to midcell after the onset of division. We use time-lapse microscopy and fluorescence recovery after photobleaching to demonstrate that DivIVA rings are highly stable and are constructed from newly synthesized DivIVA molecules. After cell division, DivIVA rings appear to collapse into patches at the rounded cell poles of separated cells, with little or no incorporation of newly synthesized subunits. Thus, changes in cell architecture mediate both the initial recruitment of DivIVA to sites of cell division and the subsequent collapse of these rings into patches (or rings of smaller diameter), while curvature-based localization of DivIVA spatially and temporally regulates Min activity.
IMPORTANCE
The Min systems of Escherichia coli and Bacillus subtilis both inhibit FtsZ assembly, but one key difference between these two species is that whereas the E. coli Min proteins localize to the poles, the B. subtilis proteins localize to nascent division sites by interaction with DivIVA and MinJ. It is unclear how MinC activity at midcell is regulated to prevent it from interfering with FtsZ engaged in medial cell division. We used superresolution microscopy to demonstrate that DivIVA and MinJ, which localize MinCD, assemble double rings that flank active division sites and septa. This curvature-based localization mechanism holds MinCD away from the FtsZ ring at midcell, and we propose that this spatial organization is the primary mechanism by which MinC activity is regulated to allow division at midcell. Curvature-based localization also conveys temporal regulation, since it ensures that MinC localizes after the onset of division.
Topics: Bacillus subtilis; Bacterial Proteins; Cell Cycle Proteins; Cell Division; Cytoskeletal Proteins
PubMed: 22108385
DOI: 10.1128/mBio.00257-11 -
The New Microbiologica Feb 2023Transcriptome analysis for the original Bacillus subtilis K1 strain and UV mutagenic strain UW07 with high yield of pectate lyase was implemented with RNA-seq. The...
Transcriptome analysis for the original Bacillus subtilis K1 strain and UV mutagenic strain UW07 with high yield of pectate lyase was implemented with RNA-seq. The function of genes was annotated and metabolic pathways were classified to look for different expression genes and classify these genes into related metabolic pathways to reveal the high-yield mechanism of pectate lyase in UW07. The results showed that 397 genes were up-regulated and 617 genes were down-regulated compared with the original strain. The up-regulated genes were mainly involved in ABC transporters, two-component system, biosynthesis of amino acids, and carbon metabolism.
Topics: Bacillus subtilis; Gene Expression Profiling; Polysaccharide-Lyases
PubMed: 36853818
DOI: No ID Found -
Developmental Cell May 2002Development in Bacillus subtilis involves a switch in the location of the cytokinetic Z ring from midcell to the pole. Time lapse photography of an FtsZ-GFP fusion... (Review)
Review
Development in Bacillus subtilis involves a switch in the location of the cytokinetic Z ring from midcell to the pole. Time lapse photography of an FtsZ-GFP fusion reveals that this switch involves a spiral intermediate and allows identification of the specific sporulation functions involved.
Topics: Bacillus subtilis; Bacterial Proteins; Cell Division; Cytoskeletal Proteins; Cytoskeleton; Green Fluorescent Proteins; Luminescent Proteins; Recombinant Fusion Proteins; Spores, Bacterial
PubMed: 12015959
DOI: 10.1016/s1534-5807(02)00178-8 -
FEMS Microbiology Reviews Mar 2010The soil-dwelling bacterium Bacillus subtilis differentiates into distinct subpopulations of specialized cells that coexist within highly structured communities. The... (Review)
Review
The soil-dwelling bacterium Bacillus subtilis differentiates into distinct subpopulations of specialized cells that coexist within highly structured communities. The coordination and interplay between these cell types requires extensive extracellular communication driven mostly by sensing self-generated secreted signals. These extracellular signals activate a set of sensor kinases, which respond by phosphorylating three major regulatory proteins, Spo0A, DegU and ComA. Each phosphorylated regulator triggers a specific differentiation program while at the same time repressing other differentiation programs. This allows a cell to differentiate in response to a specific cue, even in the presence of other, possibly conflicting, signals. The sensor kinases involved respond to an eclectic group of extracellular signals, such as quorum-sensing molecules, natural products, temperature, pH or scarcity of nutrients. This article reviews the cascades of cell differentiation pathways that are triggered by sensing extracellular signals. We also present a tentative developmental model in which the diverse cell types sequentially differentiate to achieve the proper development of the bacterial community.
Topics: Bacillus subtilis; Bacterial Proteins; Gene Expression Regulation, Bacterial; Models, Biological; Protein Kinases; Signal Transduction; Transcription Factors
PubMed: 20030732
DOI: 10.1111/j.1574-6976.2009.00199.x