Browse
Submit Data
Databases
API
Help

Dataset Information

44 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Asymmetric localization of the cell division machinery during Bacillus subtilis sporulation.

ABSTRACT: The Gram-positive bacterium Bacillus subtilis can divide via two modes. During vegetative growth, the division septum is formed at the midcell to produce two equal daughter cells. However, during sporulation, the division septum is formed closer to one pole to yield a smaller forespore and a larger mother cell. Using cryo-electron tomography, genetics and fluorescence microscopy, we found that the organization of the division machinery is different in the two septa. While FtsAZ filaments, the major orchestrators of bacterial cell division, are present uniformly around the leading edge of the invaginating vegetative septa, they are only present on the mother cell side of the invaginating sporulation septa. We provide evidence suggesting that the different distribution and number of FtsAZ filaments impact septal thickness, causing vegetative septa to be thicker than sporulation septa already during constriction. Finally, we show that a sporulation-specific protein, SpoIIE, regulates asymmetric divisome localization and septal thickness during sporulation.

SUBMITTER: Khanna K

PROVIDER: S-EPMC8192124 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Similar Datasets

Linking the Peptidoglycan Synthesis Protein Complex with Asymmetric Cell Division during Bacillus subtilis Sporulation.

Project description:Peptidoglycan is generally considered one of the main determinants of cell shape in bacteria. In rod-shaped bacteria, cell elongation requires peptidoglycan synthesis to lengthen the cell wall. In addition, peptidoglycan is synthesized at the division septum during cell division. Sporulation of Bacillus subtilis begins with an asymmetric cell division. Formation of the sporulation septum requires almost the same set of proteins as the vegetative septum; however, these two septa are significantly different. In addition to their differences in localization, the sporulation septum is thinner and it contains SpoIIE, a crucial sporulation specific protein. Here we show that peptidoglycan biosynthesis is linked to the cell division machinery during sporulation septum formation. We detected a direct interaction between SpoIIE and GpsB and found that both proteins co-localize during the early stages of asymmetric septum formation. We propose that SpoIIE is part of a multi-protein complex which includes GpsB, other division proteins and peptidoglycan synthesis proteins, and could provide a link between the peptidoglycan synthesis machinery and the complex morphological changes required for forespore formation during B. subtilis sporulation.

| S-EPMC7349982 | biostudies-literature

Dual localization pathways for the engulfment proteins during Bacillus subtilis sporulation.

Project description:Engulfment in Bacillus subtilis is mediated by two complementary systems, SpoIID, SpoIIM and SpoIIP (DMP), which are essential for engulfment, and the SpoIIQ-SpoIIIAGH (Q-AH) zipper, which provides a secondary engulfment mechanism and recruits other proteins to the septum. We here identify two mechanisms by which DMP localizes to the septum. The first depends on SpoIIB, which is recruited to the septum during division and provides a septal landmark for efficient DMP localization. However, sporangia lacking SpoIIB ultimately localize DMP and complete engulfment, suggesting a second mechanism for DMP localization. This secondary targeting pathway depends on SpoIVFA and SpoIVFB, which are recruited to the septum by the Q-AH zipper. The absence of a detectable localization phenotype in mutants lacking only SpoIVFAB (or Q-AH) suggests that SpoIIB provides the primary DMP localization pathway while SpoIVFAB provides a secondary pathway. In keeping with this hypothesis, the spoIIB spoIVFAB mutant strain has a synergistic engulfment defect at septal thinning (which requires DMP) and is completely defective in DMP localization. Thus, the Q-AH zipper both provides a compensatory mechanism for engulfment when DMP activity is reduced, and indirectly provides a compensatory mechanism for septal localization of DMP when its primary targeting pathway is disrupted.

| S-EPMC2885130 | biostudies-literature

Genetic dissection of the sporulation protein SpoIIE and its role in asymmetric division in Bacillus subtilis.

Project description:SpoIIE is a dual-function protein in Bacillus subtilis that contributes to the switch from medial to polar cell division during sporulation and is responsible for activating the cell-specific transcription factor sigma(F). SpoIIE consists of an N-terminal domain with 10 membrane-spanning segments (region I), a C-terminal phosphatase domain (region III), and a central domain (region II) of uncertain function. To investigate the role of SpoIIE in polar division, we took advantage of a system for efficiently producing polar septa during growth in a SpoIIE-dependent manner using cells engineered to produce the sporulation protein in response to an inducer. The results show that regions II and III play a critical role in polar septum formation and that specific amino acid substitutions in those regions affect the abilities of SpoIIE both to promote polar division and to localize to the division machinery. Additionally, we show that neither the phosphatase function of SpoIIE nor the N-terminal, membrane-spanning region is needed for the switch to asymmetric division.

| S-EPMC1112011 | biostudies-literature

Peptidoglycan transformations during Bacillus subtilis sporulation.

Project description:While vegetative Bacillus subtilis cells and mature spores are both surrounded by a thick layer of peptidoglycan (PG, a polymer of glycan strands cross-linked by peptide bridges), it has remained unclear whether PG surrounds prespores during engulfment. To clarify this issue, we generated a slender ?ponA mutant that enabled high-resolution electron cryotomographic imaging. Three-dimensional reconstructions of whole cells in near-native states revealed a thin PG-like layer extending from the lateral cell wall around the prespore throughout engulfment. Cryotomography of purified sacculi and fluorescent labelling of PG in live cells confirmed that PG surrounds the prespore. The presence of PG throughout engulfment suggests new roles for PG in sporulation, including a new model for how PG synthesis might drive engulfment, and obviates the need to synthesize a PG layer de novo during cortex formation. In addition, it reveals that B. subtilis can synthesize thin, Gram-negative-like PG layers as well as its thick, archetypal Gram-positive cell wall. The continuous transformations from thick to thin and back to thick during sporulation suggest that both forms of PG have the same basic architecture (circumferential). Endopeptidase activity may be the main switch that governs whether a thin or a thick PG layer is assembled.

| S-EPMC3893088 | biostudies-literature

Metal-dependent SpoIIE oligomerization stabilizes FtsZ during asymmetric division in Bacillus subtilis.

Project description:SpoIIE is a bifunctional protein involved in asymmetric septum formation and in activation of the forespore compartment-specific transcription factor σF through dephosphorylation of SpoIIAA-P. The phosphatase activity of SpoIIE requires Mn2+ as a metal cofactor. Here, we show that the presence of a metal cofactor also influences SpoIIE oligomerization and asymmetric septum formation. Absence of Mn2+ from sporulation medium results in a delay of the formation of polar FtsZ-rings, similar to a spoIIE null mutant. We purified the entire cytoplasmic part of the SpoIIE protein, and show that the protein copurifies with bound metals. Metal binding both stimulates SpoIIE oligomerization, and results in the formation of larger oligomeric structures. The presence of SpoIIE oligomers reduces FtsZ GTP hydrolysis activity and stabilizes FtsZ polymers in a light scattering assay. Combined, these results indicate that metal binding is not just required for SpoIIE phosphatase activity but also is important for SpoIIE's role in asymmetric septum formation.

| S-EPMC5373596 | biostudies-literature

Cell-wall remodeling drives engulfment during <i>Bacillus subtilis</i> sporulation.

Project description:When starved, the Gram-positive bacterium Bacillus subtilis forms durable spores for survival. Sporulation initiates with an asymmetric cell division, creating a large mother cell and a small forespore. Subsequently, the mother cell membrane engulfs the forespore in a phagocytosis-like process. However, the force generation mechanism for forward membrane movement remains unknown. Here, we show that membrane migration is driven by cell wall remodeling at the leading edge of the engulfing membrane, with peptidoglycan synthesis and degradation mediated by penicillin binding proteins in the forespore and a cell wall degradation protein complex in the mother cell. We propose a simple model for engulfment in which the junction between the septum and the lateral cell wall moves around the forespore by a mechanism resembling the 'template model'. Hence, we establish a biophysical mechanism for the creation of a force for engulfment based on the coordination between cell wall synthesis and degradation.

| S-EPMC5158138 | biostudies-literature

Sporulation in Bacillus subtilis (mother cell)

Project description:This series of experiments was designed to identify the program of gene transcription for a single differentiating cell type during sporulation in Bacillus subtilis. The mother cell is one of two cell types generated by asymmetric division of sporulating cells approximately two hours after initiation of sporulation. The program is governed by a hierarchical cascade consisting of the transcription factors: sigmaE, sigmaK, GerE, GerR (YlbO) and SpoIIID. The characterization of the sigmaE regulon was reported in Eichenberger et al. (2003), J. Mol. Biol. 327, 945-972. Here we report the data for sigmaK, GerE, GerR and SpoIIID.

2004-09-01 | GSE1620 | GEO

The molecular architecture of engulfment during Bacillus subtilis sporulation.

Project description:The study of bacterial cell biology is limited by difficulties in visualizing cellular structures at high spatial resolution within their native milieu. Here, we visualize Bacillus subtilis sporulation using cryo-electron tomography coupled with cryo-focused ion beam milling, allowing the reconstruction of native-state cellular sections at molecular resolution. During sporulation, an asymmetrically-positioned septum generates a larger mother cell and a smaller forespore. Subsequently, the mother cell engulfs the forespore. We show that the septal peptidoglycan is not completely degraded at the onset of engulfment. Instead, the septum is uniformly and only slightly thinned as it curves towards the mother cell. Then, the mother cell membrane migrates around the forespore in tiny finger-like projections, whose formation requires the mother cell SpoIIDMP protein complex. We propose that a limited number of SpoIIDMP complexes tether to and degrade the peptidoglycan ahead of the engulfing membrane, generating an irregular membrane front.

| S-EPMC6684271 | biostudies-literature

Cell wall synthesis is necessary for membrane dynamics during sporulation of Bacillus subtilis.

Project description:During Bacillus subtilis sporulation, an endocytic-like process called engulfment results in one cell being entirely encased in the cytoplasm of another cell. The driving force underlying this process of membrane movement has remained unclear, although components of the machinery have been characterized. Here we provide evidence that synthesis of peptidoglycan, the rigid, strength bearing extracellular polymer of bacteria, is a key part of the missing force-generating mechanism for engulfment. We observed that sites of peptidoglycan synthesis initially coincide with the engulfing membrane and later with the site of engulfment membrane fission. Furthermore, compounds that block muropeptide synthesis or polymerization prevented membrane migration in cells lacking a component of the engulfment machinery (SpoIIQ), and blocked the membrane fission event at the completion of engulfment in all cells. In addition, these compounds inhibited bulge and vesicle formation that occur in spoIID mutant cells unable to initiate engulfment, as did genetic ablation of a protein that polymerizes muropeptides. This is the first report to our knowledge that peptidoglycan synthesis is necessary for membrane movements in bacterial cells and has implications for the mechanism of force generation during cytokinesis.

| S-EPMC2893020 | biostudies-literature

Repeated triggering of sporulation in Bacillus subtilis selects against a protein that affects the timing of cell division.

Project description:Bacillus subtilis sporulation is a last-resort phenotypical adaptation in response to starvation. The regulatory network underlying this developmental pathway has been studied extensively. However, how sporulation initiation is concerted in relation to the environmental nutrient availability is poorly understood. In a fed-batch fermentation set-up, in which sporulation of ultraviolet (UV)-mutagenized B. subtilis is repeatedly triggered by periods of starvation, fitter strains with mutated tagE evolved. These mutants display altered timing of phenotypical differentiation. The substrate for the wall teichoic acid (WTA)-modifying enzyme TagE, UDP-glucose, has recently been shown to be an intracellular proxy for nutrient availability, and influences the timing of cell division. Here we suggest that UDP-glucose also influences timing of cellular differentiation.

| S-EPMC3869009 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data