scholarly journals Biofi lm formation by an ancestral strain (NCIB3610) of the commonly used Bacillus subtilis laboratory strain, 168, as monitored by the formation of rugose colonies. The colony surface is highly hydrophobic as evidenced by the beading of a water droplet (

2014 ◽  
Vol 93 (4) ◽  
pp. i-i
Keyword(s):  
Bacillus Subtilis ◽  
Water Droplet ◽  
Laboratory Strain ◽  
Colony Surface ◽  
Highly Hydrophobic ◽  
Ancestral Strain

scholarly journals Molecular Physiological Characterization of a High Heat Resistant Spore Forming Bacillus subtilis Food Isolate

2021 ◽  
Vol 9 (3) ◽  
pp. 667
Author(s):  
Zhiwei Tu ◽  
Peter Setlow ◽  
Stanley Brul ◽  
Gertjan Kramer
Keyword(s):  
Bacillus Subtilis ◽  
Heat Resistance ◽  
Dipicolinic Acid ◽  
Laboratory Strain ◽  
High Heat ◽  
High Heat Resistance ◽  
Vegetative Cells ◽  
Heat Resistant ◽  
Food Isolate ◽  
Wet Heat

Bacterial endospores (spores) are among the most resistant living forms on earth. Spores of Bacillus subtilis A163 show extremely high resistance to wet heat compared to spores of laboratory strains. In this study, we found that spores of B. subtilis A163 were indeed very wet heat resistant and released dipicolinic acid (DPA) very slowly during heat treatment. We also determined the proteome of vegetative cells and spores of B. subtilis A163 and the differences in these proteomes from those of the laboratory strain PY79, spores of which are much less heat resistant. This proteomic characterization identified 2011 proteins in spores and 1901 proteins in vegetative cells of B. subtilis A163. Surprisingly, spore morphogenic protein SpoVM had no homologs in B. subtilis A163. Comparing protein expression between these two strains uncovered 108 proteins that were differentially present in spores and 93 proteins differentially present in cells. In addition, five of the seven proteins on an operon in strain A163, which is thought to be primarily responsible for this strain’s spores high heat resistance, were also identified. These findings reveal proteomic differences of the two strains exhibiting different resistance to heat and form a basis for further mechanistic analysis of the high heat resistance of B. subtilis A163 spores.

scholarly journals Effects of Phosphorelay Perturbations on Architecture, Sporulation, and Spore Resistance in Biofilms of Bacillus subtilis

2006 ◽  
Vol 188 (8) ◽  
pp. 3099-3109 ◽  
Author(s):  
Jan-Willem Veening ◽  
Oscar P. Kuipers ◽  
Stanley Brul ◽  
Klaas J. Hellingwerf ◽  
Remco Kort
Keyword(s):  
Bacillus Subtilis ◽  
Fluorescent Protein ◽  
Current Model ◽  
Laboratory Strain ◽  
Time Lapse ◽  
Rich Media ◽  
Flat Structures ◽  
Reporter Strains ◽  
Green Fluorescent ◽  
Fluorescent Protein Reporter

ABSTRACT The spore-forming bacterium Bacillus subtilis is able to form highly organized multicellular communities called biofilms. This coordinated bacterial behavior is often lost in domesticated or laboratory strains as a result of planktonic growth in rich media for many generations. However, we show here that the laboratory strain B. subtilis 168 is still capable of forming spatially organized multicellular communities on minimal medium agar plates, exemplified by colonies with vein-like structures formed by elevated bundles of cells. In line with the current model for biofilm formation, we demonstrate that overproduction of the phosphorelay components KinA and Spo0A stimulates bundle formation, while overproduction of the transition state regulators AbrB and SinR leads to repression of formation of elevated bundles. Time-lapse fluorescence microscopy studies of B. subtilis green fluorescent protein reporter strains show that bundles are preferential sites for spore formation and that flat structures surrounding the bundles contain vegetative cells. The elevated bundle structures are formed prior to sporulation, in agreement with a genetic developmental program in which these processes are sequentially activated. Perturbations of the phosphorelay by disruption and overexpression of genes that lead to an increased tendency to sporulate result in the segregation of sporulation mutations and decreased heat resistance of spores in biofilms. These results stress the importance of a balanced control of the phosphorelay for biofilm and spore development.

scholarly journals Identification ofypqPas a New Bacillus subtilis Biofilm Determinant That Mediates the Protection of Staphylococcus aureus against Antimicrobial Agents in Mixed-Species Communities

2014 ◽  
Vol 81 (1) ◽  
pp. 109-118 ◽  
Author(s):  
Pilar Sanchez-Vizuete ◽  
Dominique Le Coq ◽  
Arnaud Bridier ◽  
Jean-Marie Herry ◽  
Stéphane Aymerich ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Bacillus Subtilis ◽  
Extracellular Polymeric Substances ◽  
Antimicrobial Agents ◽  
Three Dimensional ◽  
Laboratory Strain ◽  
Spatial Arrangement ◽  
Content Type ◽  
Microbial Life ◽  
Multispecies Biofilms

ABSTRACTIn most habitats, microbial life is organized in biofilms, three-dimensional edifices sustained by extracellular polymeric substances that enable bacteria to resist harsh and changing environments. Under multispecies conditions, bacteria can benefit from the polymers produced by other species (“public goods”), thus improving their survival under toxic conditions. A recent study showed that aBacillus subtilishospital isolate (NDmed) was able to protectStaphylococcus aureusfrom biocide action in multispecies biofilms. In this work, we identifiedypqP, a gene whose product is required in NDmed for thick-biofilm formation on submerged surfaces and for resistance to two biocides widely used in hospitals. NDmed andS. aureusformed mixed biofilms, and both their spatial arrangement and pathogen protection were mediated by YpqP. FunctionalypqPis present in other naturalB. subtilisbiofilm-forming isolates. However, the gene is disrupted by the SPβ prophage in the weak submerged-biofilm-forming strains NCIB3610 and 168, which are both less resistant than NDmed to the biocides tested. Furthermore, in a 168 laboratory strain cured of the SPβ prophage, the reestablishment of a functionalypqPgene led to increased thickness and resistance to biocides of the associated biofilms. We therefore propose that YpqP is a new and important determinant ofB. subtilissurface biofilm architecture, protection against exposure to toxic compounds, and social behavior in bacterial communities.

scholarly journals Novel Methods for Genetic Transformation of Natural Bacillus subtilis Isolates Used To Study the Regulation of the Mycosubtilin and Surfactin Synthetases

2007 ◽  
Vol 73 (11) ◽  
pp. 3490-3496 ◽  
Author(s):  
Erwin H. Duitman ◽  
Dobek Wyczawski ◽  
Ludolf G. Boven ◽  
Gerard Venema ◽  
Oscar P. Kuipers ◽  
...  
Keyword(s):  
Bacillus Subtilis ◽  
Response Regulator ◽  
Laboratory Strain ◽  
Synergistic Activity ◽  
Strain Atcc ◽  
Lipopeptide Antibiotics ◽  
Natural Isolates ◽  
Novel Methods ◽  
Transition State Regulator

ABSTRACT Natural isolates of Bacillus subtilis are often difficult to transform due to their low genetic competence levels. Here we describe two methods that stimulate natural transformation. The first method uses plasmid pGSP12, which expresses the competence transcription factor ComK and stimulates competence development about 100-fold. The second method stimulates Campbell-type recombination of DNA ligation mixtures in B. subtilis by the addition of polyethylene glycol. We employed these novel methods to study the regulation of the synthetases for the lipopeptide antibiotics mycosubtilin (myc) and surfactin (srfA) in B. subtilis strain ATCC 6633. By means of lacZ reporter fusions, it was shown that the expression of srfA is >100 times lower in strain ATCC 6633 than in the laboratory strain B. subtilis 168. Expression of the myc operon was highest in rich medium, whereas srfA expression reached maximal levels in minimal medium. Further genetic analyses showed that the srfA operon is mainly regulated by the response regulator ComA, while the myc operon is primarily regulated by the transition-state regulator AbrB. Although there is in vitro evidence for a synergistic activity of mycosubtilin and surfactin, the expression of both lipopeptide antibiotics is clearly not coordinated.

scholarly journals Genomic Heterogeneity and Ecological Speciation within One Subspecies of Bacillus subtilis

2014 ◽  
Vol 80 (16) ◽  
pp. 4842-4853 ◽  
Author(s):  
Sarah Kopac ◽  
Zhang Wang ◽  
Jane Wiedenbeck ◽  
Jessica Sherry ◽  
Martin Wu ◽  
...  
Keyword(s):  
Bacillus Subtilis ◽  
Positive Selection ◽  
Laboratory Strain ◽  
Ecological Speciation ◽  
Amino Acid Sequences ◽  
Metabolic System ◽  
Homogeneous Population ◽  
Content Type ◽  
Bacterial Speciation ◽  
Close Relatives

ABSTRACTClosely related bacterial genomes usually differ in gene content, suggesting that nearly every strain in nature may be ecologically unique. We have tested this hypothesis by sequencing the genomes of extremely close relatives within a recognized taxon and analyzing the genomes for evidence of ecological distinctness. We compared the genomes of four Death Valley isolates plus the laboratory strain W23, all previously classified asBacillus subtilissubsp.spizizeniiand hypothesized through multilocus analysis to be members of the same ecotype (an ecologically homogeneous population), named putative ecotype 15 (PE15). These strains showed a history of positive selection on amino acid sequences in 38 genes. Each of the strains was under a different regimen of positive selection, suggesting that each strain is ecologically unique and represents a distinct ecological speciation event. The rate of speciation appears to be much faster than can be resolved with multilocus sequencing. Each PE15 strain contained unique genes known to confer a function for bacteria. Remarkably, no unique gene conferred a metabolic system or subsystem function that was not already present in all the PE15 strains sampled. Thus, the origin of ecotypes within this clade shows no evidence of qualitative divergence in the set of resources utilized. Ecotype formation within this clade is consistent with the nanoniche model of bacterial speciation, in which ecotypes use the same set of resources but in different proportions, and genetic cohesion extends beyond a single ecotype to the set of ecotypes utilizing the same resources.

scholarly journals Single-cell analysis in situ in a Bacillus subtilis swarming community identifies distinct spatially separated subpopulations differentially expressing hag (flagellin), including specialized swarmers

Microbiology ◽  
2011 ◽  
Vol 157 (9) ◽  
pp. 2456-2469 ◽  
Author(s):  
Kassem Hamze ◽  
Sabine Autret ◽  
Krzysztof Hinc ◽  
Soumaya Laalami ◽  
Daria Julkowska ◽  
...  
Keyword(s):  
Bacillus Subtilis ◽  
Single Cell ◽  
Single Cell Analysis ◽  
Laboratory Strain ◽  
Cell Types ◽  
Spatiotemporal Pattern ◽  
Cell Analysis ◽  
Wide Range ◽  
Low Humidity

The non-domesticated Bacillus subtilis strain 3610 displays, over a wide range of humidity, hyper-branched, dendritic, swarming-like migration on a minimal agar medium. At high (70 %) humidity, the laboratory strain 168 sfp + (producing surfactin) behaves very similarly, although this strain carries a frameshift mutation in swrA, which another group has shown under their conditions (which include low humidity) is essential for swarming. We reconcile these different results by demonstrating that, while swrA is essential for dendritic migration at low humidity (30–40 %), it is dispensable at high humidity. Dendritic migration (flagella- and surfactin-dependent) of strains 168 sfp + swrA and 3610 involves elongation of dendrites for several hours as a monolayer of cells in a thin fluid film. This enabled us to determine in situ the spatiotemporal pattern of expression of some key players in migration as dendrites develop, using gfp transcriptional fusions for hag (encoding flagellin), comA (regulation of surfactin synthesis) as well as eps (exopolysaccharide synthesis). Quantitative (single-cell) analysis of hag expression in situ revealed three spatially separated subpopulations or cell types: (i) networks of chains arising early in the mother colony (MC), expressing eps but not hag; (ii) largely immobile cells in dendrite stems expressing intermediate levels of hag; and (iii) a subpopulation of cells with several distinctive features, including very low comA expression but hyper-expression of hag (and flagella). These specialized cells emerge from the MC to spearhead the terminal 1 mm of dendrite tips as swirling and streaming packs, a major characteristic of swarming migration. We discuss a model for this swarming process, emphasizing the importance of population density and of the complementary roles of packs of swarmers driving dendrite extension, while non-mobile cells in the stems extend dendrites by multiplication.

scholarly journals Increased Competitive Fitness of Bacillus subtilis under Nonsporulating Conditions via Inactivation of Pleiotropic Regulators AlsR, SigD, and SigW

2012 ◽  
Vol 78 (9) ◽  
pp. 3500-3503 ◽  
Author(s):  
Wayne L. Nicholson
Keyword(s):  
Bacillus Subtilis ◽  
Regulatory Genes ◽  
Competitive Fitness ◽  
Content Type ◽  
Pleiotropic Regulators ◽  
Ancestral Strain

ABSTRACTPrevious studies implicated loss of motility and mutations of thealsRandsigWregulatory genes in enhanced fitness of theBacillus subtilisevolved strain WN716 over that of its ancestral strain WN624. The fitness of strains carrying knockout mutationsalsR::spc,sigD::kan, and/orsigW::ermwas measured and compared to that of the congenic ancestral strain by competition experiments.

Evaluation of Bacillus subtilis strains as probiotics and their potential as a food ingredient

2012 ◽  
Vol 3 (2) ◽  
pp. 127-135 ◽  
Author(s):  
P. Permpoonpattana ◽  
H.A. Hong ◽  
R. Khaneja ◽  
S.M. Cutting
Keyword(s):  
Bacillus Subtilis ◽  
Food Additives ◽  
Laboratory Strain ◽  
Food Ingredient ◽  
Log Reduction ◽  
Cellular Immune Responses ◽  
Gastric Fluids ◽  
Cellular Immune ◽  
Gastro Intestinal Tract ◽  
Potential Food

Spores of Bacillus subtilis including one strain used commercially were evaluated for their potential value as a probiotic and as potential food additives. Two isolates of B. subtilis examined here were HU58, a human isolate and PXN21, a strain used in an existing commercial product. Compared to a domesticated laboratory strain of B. subtilis both isolates carried traits that could prove advantageous in the human gastro-intestinal tract. This included full resistance to gastric fluids, rapid sporulation and the formation of robust biofilms. We also showed that PXN21 spores when administered weekly to mice conferred non-specific cellular immune responses, indicative signs of the stimulation of innate immunity. Spores mixed in wholemeal biscuits were found to survive baking at 235 °C for 8 minutes with only a 1-log reduction in viability. That spores can survive the baking process offers the possibility of using spores as probiotic supplements in a range of novel food products.

A bioinspired approach to produce parahydrophobic properties using PEDOP conducting polymers with branched alkyl chains

2015 ◽  
Vol 87 (8) ◽  
pp. 805-814 ◽  
Author(s):  
Claudio Mortier ◽  
Thierry Darmanin ◽  
Frédéric Guittard
Keyword(s):  
Conducting Polymers ◽  
Conducting Polymer ◽  
Water Droplet ◽  
High Water ◽  
Hydrophilic Polymers ◽  
Water Harvesting ◽  
Alkyl Chains ◽  
Water Adhesion ◽  
Highly Hydrophobic ◽  
Conducting Polymer Films

Abstract In nature, several plants and insects, such as the Rosa montana petals or the gecko foot, are highly hydrophobic but with an extremely high water adhesion. These properties are called parahydrophobic. Here, in order to reproduce such properties we have developed original 3,4-ethylenedioxypyrrole monomers containing branched alkyl chains in order to have intrinsically hydrophilic polymers. In certain conditions, the electrodeposited conducting polymer films are parahydrophobic due to the presence fibrous structures forming large agglomerates. On such surfaces, a water droplet deposited on them remains stuck even after a substrate inclination of 180°. Such properties are extremely interesting for applications in water harvesting, for example.

Sign in / Sign up

Export Citation Format

Share Document