scholarly journals Critical Components of the Conjugation Machinery of the Integrative and Conjugative Element ICEBs1of Bacillus subtilis

2015 ◽  
Vol 197 (15) ◽  
pp. 2558-2567 ◽  
Author(s):  
Cori T. Leonetti ◽  
Matt A. Hamada ◽  
Stephanie J. Laurer ◽  
Matthew P. Broulidakis ◽  
Kyle J. Swerdlow ◽  
...  
Keyword(s):  
Bacillus Subtilis ◽  
Fluorescent Protein ◽  
Secretion System ◽  
Dna Transfer ◽  
Bacterial Evolution ◽  
Content Type ◽  
Type Iv ◽  
Critical Components ◽  
Green Fluorescent ◽  
Integrative And Conjugative Element

ABSTRACTConjugation, or mating, plays a profound role in bacterial evolution by spreading genes that allow bacteria to adapt to and colonize new niches. ICEBs1, an integrative and conjugative element ofBacillus subtilis, can transfer itself and mobilize resident plasmids. DNA transfer is mediated by a type IV secretion system (T4SS). Characterized components of the ICEBs1T4SS include the conserved VirB4-like ATPase ConE, the bifunctional cell wall hydrolase CwlT, and the presumed VirD4-like coupling protein ConQ. A fusion of ConE to green fluorescent protein (GFP) localizes to the membrane preferentially at the cell poles. One or more ICEBs1proteins are required for ConE's localization at the membrane, as ConE lacks predicted transmembrane segments and ConE-GFP is found dispersed throughout the cytoplasm in cells lacking ICEBs1. Here, we analyzed five ICEBs1genes to determine if they are required for DNA transfer and/or ConE-GFP localization. We found thatconB,conC,conD, andconG, but notyddF, are required for both ICEBs1transfer and plasmid mobilization. All four required genes encode predicted integral membrane proteins.conBand, to some extent,conDwere required for localization of ConE-GFP to the membrane. Using an adenylate cyclase-based bacterial two-hybrid system, we found that ConE interacts with ConB. We propose a model in which the ICEBs1conjugation machinery is composed of ConB, ConC, ConD, ConE, ConG, CwlT, ConQ, and possibly other ICEBs1proteins, and that ConB interacts with ConE, helping to recruit and/or maintain ConE at the membrane.IMPORTANCEConjugation is a major form of horizontal gene transfer and has played a profound role in bacterial evolution by moving genes, including those involved in antibiotic resistance, metabolism, symbiosis, and infectious disease. During conjugation, DNA is transferred from cell to cell through the conjugation machinery, a type of secretion system. Relatively little is known about the conjugation machinery of Gram-positive bacteria. Here, we analyzed five genes of the integrative and conjugative element ICEBs1ofBacillus subtilis. Our research identifies four new components of the ICEBs1conjugation machinery (ConB, ConC, ConD, and ConG) and shows an interaction between ConB and ConE that is required for ConE to associate with the cell membrane.

scholarly journals Bacteriophage SP01 Gene Product 56 Inhibits Bacillus subtilis Cell Division by Interacting with FtsL and Disrupting Pbp2B and FtsW Recruitment

2020 ◽  
Vol 203 (2) ◽  
pp. e00463-20
Author(s):  
Amit Bhambhani ◽  
Isabella Iadicicco ◽  
Jules Lee ◽  
Syed Ahmed ◽  
Max Belfatto ◽  
...  
Keyword(s):  
Cell Wall ◽  
Bacillus Subtilis ◽  
Cell Division ◽  
Gene Product ◽  
Fluorescent Protein ◽  
Lytic Bacteriophage ◽  
Cell Wall Synthesis ◽  
Content Type ◽  
Ftsz Ring ◽  
Green Fluorescent

ABSTRACTPrevious work identified gene product 56 (gp56), encoded by the lytic bacteriophage SP01, as being responsible for inhibition of Bacillus subtilis cell division during its infection. Assembly of the essential tubulin-like protein FtsZ into a ring-shaped structure at the nascent site of cytokinesis determines the timing and position of division in most bacteria. This FtsZ ring serves as a scaffold for recruitment of other proteins into a mature division-competent structure permitting membrane constriction and septal cell wall synthesis. Here, we show that expression of the predicted 9.3-kDa gp56 of SP01 inhibits later stages of B. subtilis cell division without altering FtsZ ring assembly. Green fluorescent protein-tagged gp56 localizes to the membrane at the site of division. While its localization does not interfere with recruitment of early division proteins, gp56 interferes with the recruitment of late division proteins, including Pbp2b and FtsW. Imaging of cells with specific division components deleted or depleted and two-hybrid analyses suggest that gp56 localization and activity depend on its interaction with FtsL. Together, these data support a model in which gp56 interacts with a central part of the division machinery to disrupt late recruitment of the division proteins involved in septal cell wall synthesis.IMPORTANCE Studies over the past decades have identified bacteriophage-encoded factors that interfere with host cell shape or cytokinesis during viral infection. The phage factors causing cell filamentation that have been investigated to date all act by targeting FtsZ, the conserved prokaryotic tubulin homolog that composes the cytokinetic ring in most bacteria and some groups of archaea. However, the mechanisms of several phage factors that inhibit cytokinesis, including gp56 of bacteriophage SP01 of Bacillus subtilis, remain unexplored. Here, we show that, unlike other published examples of phage inhibition of cytokinesis, gp56 blocks B. subtilis cell division without targeting FtsZ. Rather, it utilizes the assembled FtsZ cytokinetic ring to localize to the division machinery and to block recruitment of proteins needed for septal cell wall synthesis.

scholarly journals Engineering of Bacillus subtilis Strains To Allow Rapid Characterization of Heterologous Diguanylate Cyclases and Phosphodiesterases

2014 ◽  
Vol 80 (19) ◽  
pp. 6167-6174 ◽  
Author(s):  
Xiaohui Gao ◽  
Xiao Dong ◽  
Sundharraman Subramanian ◽  
Paige M. Matthews ◽  
Caleb A. Cooper ◽  
...  
Keyword(s):  
Bacillus Subtilis ◽  
Biofilm Formation ◽  
Fluorescent Protein ◽  
Threshold Level ◽  
Metabolic Enzymes ◽  
Guanosine Monophosphate ◽  
Content Type ◽  
Diguanylate Cyclases ◽  
Rapid Characterization ◽  
Green Fluorescent

ABSTRACTMicrobial processes, including biofilm formation, motility, and virulence, are often regulated by changes in the available concentration of cyclic dimeric guanosine monophosphate (c-di-GMP). Generally, high c-di-GMP concentrations are correlated with decreased motility and increased biofilm formation and low c-di-GMP concentrations are correlated with an increase in motility and activation of virulence pathways. The study of c-di-GMP is complicated, however, by the fact that organisms often encode dozens of redundant enzymes that synthesize and hydrolyze c-di-GMP, diguanylate cyclases (DGCs), and c-di-GMP phosphodiesterases (PDEs); thus, determining the contribution of any one particular enzyme is challenging. In an effort to develop a facile system to study c-di-GMP metabolic enzymes, we have engineered a suite ofBacillus subtilisstrains to assess the effect of individual heterologously expressed proteins on c-di-GMP levels. As a proof of principle, we characterized all 37 known genes encoding predicted DGCs and PDEs inClostridium difficileusing parallel readouts of swarming motility and fluorescence from green fluorescent protein (GFP) expressed under the control of a c-di-GMP-controlled riboswitch. We found that 27 of the 37 putativeC. difficile630 c-di-GMP metabolic enzymes had either active cyclase or phosphodiesterase activity, with agreement between our motility phenotypes and fluorescence-based c-di-GMP reporter. Finally, we show that there appears to be a threshold level of c-di-GMP needed to inhibit motility inBacillus subtilis.

scholarly journals csrTRepresents a New Class ofcsrA-Like Regulatory Genes Associated with Integrative Conjugative Elements of Legionella pneumophila

2015 ◽  
Vol 198 (3) ◽  
pp. 553-564 ◽  
Author(s):  
Zachary D. Abbott ◽  
Kaitlin J. Flynn ◽  
Brenda G. Byrne ◽  
Sampriti Mukherjee ◽  
Daniel B. Kearns ◽  
...  
Keyword(s):  
Bacillus Subtilis ◽  
Legionella Pneumophila ◽  
Mobile Genetic Elements ◽  
Secretion System ◽  
Type Iv Secretion ◽  
Type Iv Secretion System ◽  
Content Type ◽  
Type Iv ◽  
Horizontal Spread ◽  
Integrative Conjugative Elements

ABSTRACTBacterial evolution is accelerated by mobile genetic elements. To spread horizontally and to benefit the recipient bacteria, genes encoded on these elements must be properly regulated. Among the legionellae are multiple integrative conjugative elements (ICEs) that each encode a paralog of the broadly conserved regulatorcsrA. Using bioinformatic analyses, we deduced that specificcsrAparalogs are coinherited with particular lineages of the type IV secretion system that mediates horizontal spread of its ICE, suggesting a conserved regulatory interaction. As a first step to investigate the contribution ofcsrAregulators to this class of mobile genetic elements, we analyzed here the activity of thecsrAparalog encoded onLegionella pneumophilaICE-βox. Deletion of this gene, which we namecsrT, had no observed effect under laboratory conditions. However, ectopic expression ofcsrTabrogated the protection to hydrogen peroxide and macrophage degradation that ICE-βox confers toL. pneumophila. When ectopically expressed,csrTalso repressedL. pneumophilaflagellin production and motility, a function similar to the core genome's canonicalcsrA. Moreover,csrTrestored the repression of motility tocsrAmutants ofBacillus subtilis, a finding consistent with the predicted function of CsrT as an mRNA binding protein. Since all known ICEs of legionellae encode coinheritedcsrA-type IV secretion system pairs, we postulate that CsrA superfamily proteins regulate ICE activity to increase their horizontal spread, thereby expandingL. pneumophilaversatility.IMPORTANCEICEs are mobile DNA elements whose type IV secretion machineries mediate spread among bacterial populations. All surveyed ICEs within theLegionellagenus also carry paralogs of the essential life cycle regulatorcsrA. It is striking that thecsrAloci could be classified into distinct families based on either their sequence or the subtype of the adjacent type IV secretion system locus. To investigate whether ICE-encodedcsrAparalogs are bona fide regulators, we analyzed ICE-βox as a model system. When expressed ectopically, itscsrAparalog inhibited multiple ICE-βox phenotypes, as well as the motility of not onlyLegionellabut alsoBacillus subtilis. Accordingly, we predict that CsrA regulators equip legionellae ICEs to promote their spread via dedicated type IV secretion systems.

scholarly journals Benchmarking Various Green Fluorescent Protein Variants in Bacillus subtilis, Streptococcus pneumoniae, and Lactococcus lactis for Live Cell Imaging

2013 ◽  
Vol 79 (20) ◽  
pp. 6481-6490 ◽  
Author(s):  
Wout Overkamp ◽  
Katrin Beilharz ◽  
Ruud Detert Oude Weme ◽  
Ana Solopova ◽  
Harma Karsens ◽  
...  
Keyword(s):  
Bacillus Subtilis ◽  
Green Fluorescent Protein ◽  
Streptococcus Pneumoniae ◽  
Lactococcus Lactis ◽  
Cell Biology ◽  
Fluorescent Protein ◽  
Protein Localization ◽  
Experimental Conditions ◽  
Content Type ◽  
Green Fluorescent

ABSTRACTGreen fluorescent protein (GFP) offers efficient ways of visualizing promoter activity and protein localizationin vivo, and many different variants are currently available to study bacterial cell biology. Which of these variants is best suited for a certain bacterial strain, goal, or experimental condition is not clear. Here, we have designed and constructed two “superfolder” GFPs with codon adaptation specifically forBacillus subtilisandStreptococcus pneumoniaeand have benchmarked them against five other previously available variants of GFP inB. subtilis,S. pneumoniae, andLactococcus lactis, using promoter-gfpfusions. Surprisingly, the best-performing GFP under our experimental conditions inB. subtiliswas the one codon optimized forS. pneumoniaeandvice versa. The data and tools described in this study will be useful for cell biology studies in low-GC-rich Gram-positive bacteria.

scholarly journals Polar Positioning of a Conjugation Protein from the Integrative and Conjugative Element ICEBs1 of Bacillus subtilis

2009 ◽  
Vol 192 (1) ◽  
pp. 38-45 ◽  
Author(s):  
Melanie B. Berkmen ◽  
Catherine A. Lee ◽  
Emma-Kate Loveday ◽  
Alan D. Grossman
Keyword(s):  
Bacillus Subtilis ◽  
Fluorescent Protein ◽  
Donor Cell ◽  
Subcellular Location ◽  
Conjugative Transfer ◽  
Protein Fusion ◽  
Cell Pole ◽  
A Cell ◽  
Green Fluorescent ◽  
Integrative And Conjugative Element

ABSTRACT ICEBs1 is an integrative and conjugative element found in the chromosome of Bacillus subtilis. ICEBs1 encodes functions needed for its excision and transfer to recipient cells. We found that the ICEBs1 gene conE (formerly yddE) is required for conjugation and that conjugative transfer of ICEBs1 requires a conserved ATPase motif of ConE. ConE belongs to the HerA/FtsK superfamily of ATPases, which includes the well-characterized proteins FtsK, SpoIIIE, VirB4, and VirD4. We found that a ConE-GFP (green fluorescent protein) fusion associated with the membrane predominantly at the cell poles in ICEBs1 donor cells. At least one ICEBs1 product likely interacts with ConE to target it to the membrane and cell poles, as ConE-GFP was dispersed throughout the cytoplasm in a strain lacking ICEBs1. We also visualized the subcellular location of ICEBs1. When integrated in the chromosome, ICEBs1 was located near midcell along the length of the cell, a position characteristic of that chromosomal region. Following excision, ICEBs1 was more frequently found near a cell pole. Excision of ICEBs1 also caused altered positioning of at least one component of the replisome. Taken together, our findings indicate that ConE is a critical component of the ICEBs1 conjugation machinery, that conjugative transfer of ICEBs1 from B. subtilis likely initiates at a donor cell pole, and that ICEBs1 affects the subcellular position of the replisome.

scholarly journals The Canonical Twin-Arginine Translocase Components Are Not Required for Secretion of Folded Green Fluorescent Protein from the Ancestral Strain of Bacillus subtilis

2014 ◽  
Vol 80 (10) ◽  
pp. 3219-3232 ◽  
Author(s):  
Anthony J. Snyder ◽  
Sampriti Mukherjee ◽  
J. Kyle Glass ◽  
Daniel B. Kearns ◽  
Suchetana Mukhopadhyay
Keyword(s):  
Bacillus Subtilis ◽  
Green Fluorescent Protein ◽  
Signal Peptide ◽  
Secretory Pathway ◽  
Fluorescent Protein ◽  
Secretion Systems ◽  
Content Type ◽  
Twin Arginine Translocase ◽  
Green Fluorescent ◽  
Ancestral Strain

ABSTRACTCellular processes, such as the digestion of macromolecules, phosphate acquisition, and cell motility, require bacterial secretion systems. InBacillus subtilis, the predominant protein export pathways are Sec (generalized secretory pathway) and Tat (twin-arginine translocase). Unlike Sec, which secretes unfolded proteins, the Tat machinery secretes fully folded proteins across the plasma membrane and into the medium. Proteins are directed for Tat-dependent export by N-terminal signal peptides that contain a conserved twin-arginine motif. Thus, utilizing the Tat secretion system by fusing a Tat signal peptide is an attractive strategy for the production and export of heterologous proteins. As a proof of concept, we expressed green fluorescent protein (GFP) fused to the PhoD Tat signal peptide in the laboratory and ancestral strains ofB. subtilis. Secretion of the Tat-GFP construct, as well as secretion of proteins in general, was substantially increased in the ancestral strain. Furthermore, our results show that secreted, fluorescent GFP could be purified directly from the extracellular medium. Nonetheless, export was not dependent on the known Tat secretion components or the signal peptide twin-arginine motif. We propose that the ancestral strain contains additional Tat components and/or secretion regulators that were abrogated following domestication.

scholarly journals Imaging and Analysis of Pseudomonas aeruginosa Swarming and Rhamnolipid Production

2011 ◽  
Vol 77 (23) ◽  
pp. 8310-8317 ◽  
Author(s):  
Joshua D. Morris ◽  
Jessica L. Hewitt ◽  
Lawrence G. Wolfe ◽  
Nachiket G. Kamatkar ◽  
Sarah M. Chapman ◽  
...  
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Fluorescent Protein ◽  
Nile Red ◽  
Temporal Distribution ◽  
Time Lapse ◽  
Content Type ◽  
Rhamnolipid Production ◽  
Serovar Typhimurium ◽  
Surface Motility ◽  
Green Fluorescent

ABSTRACTMany bacteria spread over surfaces by “swarming” in groups. A problem for scientists who study swarming is the acquisition of statistically significant data that distinguish two observations or detail the temporal patterns and two-dimensional heterogeneities that occur. It is currently difficult to quantify differences between observed swarm phenotypes. Here, we present a method for acquisition of temporal surface motility data using time-lapse fluorescence and bioluminescence imaging. We specifically demonstrate three applications of our technique with the bacteriumPseudomonas aeruginosa. First, we quantify the temporal distribution ofP. aeruginosacells tagged with green fluorescent protein (GFP) and the surfactant rhamnolipid stained with the lipid dye Nile red. Second, we distinguish swarming ofP. aeruginosaandSalmonella entericaserovar Typhimurium in a coswarming experiment. Lastly, we quantify differences in swarming and rhamnolipid production of severalP. aeruginosastrains. While the best swarming strains produced the most rhamnolipid on surfaces, planktonic culture rhamnolipid production did not correlate with surface growth rhamnolipid production.

scholarly journals Vibrio cholerae Triggers SOS and Mutagenesis in Response to a Wide Range of Antibiotics: a Route towards Multiresistance

2011 ◽  
Vol 55 (5) ◽  
pp. 2438-2441 ◽  
Author(s):  
Zeynep Baharoglu ◽  
Didier Mazel
Keyword(s):  
Escherichia Coli ◽  
Antibiotic Resistance ◽  
Vibrio Cholerae ◽  
Fluorescent Protein ◽  
Resistance Development ◽  
Content Type ◽  
E Coli ◽  
Wide Range ◽  
Green Fluorescent ◽  
Regulated Promoters

ABSTRACTAntibiotic resistance development has been linked to the bacterial SOS stress response. InEscherichia coli, fluoroquinolones are known to induce SOS, whereas other antibiotics, such as aminoglycosides, tetracycline, and chloramphenicol, do not. Here we address whether various antibiotics induce SOS inVibrio cholerae. Reporter green fluorescent protein (GFP) fusions were used to measure the response of SOS-regulated promoters to subinhibitory concentrations of antibiotics. We show that unlike the situation withE. coli, all these antibiotics induce SOS inV. cholerae.

Sign in / Sign up

Export Citation Format

Share Document