scholarly journals In vitro reconstitution of divisome activation

2021 ◽  
Author(s):  
Philipp Radler ◽  
Natalia Baranova ◽  
Paulo Caldas ◽  
Christoph Sommer ◽  
Mar López-Pelegrín ◽  
...  
Keyword(s):  
Cell Division ◽  
Bacterial Cell ◽  
Current Model ◽  
Monomeric Form ◽  
Bacterial Cell Division ◽  
Cytoskeletal Structure ◽  
In Vitro Reconstitution ◽  
Z Ring ◽  
Quantitative Fluorescence

Bacterial cell division is coordinated by the Z-ring, a cytoskeletal structure of treadmilling filaments of FtsZ and their membrane anchors, FtsA and ZipA. For divisome maturation and initiation of constriction, the widely conserved actin-homolog FtsA plays a central role, as it links downstream cell division proteins in the membrane to the Z-ring in the cytoplasm. According to the current model, FtsA initiates cell constriction by switching from an inactive polymeric conformation to an active monomeric form, which then stabilizes the Z-ring and recruits downstream proteins such as FtsN. However, direct biochemical evidence for this mechanism is missing so far. Here, we used biochemical reconstitution experiments in combination with quantitative fluorescence microscopy to study the mechanism of divisome activation in vitro. By comparing the properties of wildtype FtsA and FtsA R286W, a gain-of-function mutant thought to mimic its active state, we found that active FtsA outperforms the wildtype protein in replicating FtsZ treadmilling dynamics, filament stabilization and FtsN recruitment. We could attribute these differences to a faster membrane exchange of FtsA R286W as well as its higher packing density below FtsZ filaments. Using FRET microscopy, we also show that binding of FtsN does not compete with, but promotes FtsA self-interaction. Together, our findings shed new light on the assembly and activation of the bacterial cell division machinery and the mechanism of how FtsA initiates cell constriction.

scholarly journals Cooperative ordering of treadmilling filaments in cytoskeletal networks of FtsZ and its crosslinker ZapA

2019 ◽  
Vol 10 (1) ◽  
Author(s):  
Paulo Caldas ◽  
Mar López-Pelegrín ◽  
Daniel J. G. Pearce ◽  
Nazmi Burak Budanur ◽  
Jan Brugués ◽  
...  
Keyword(s):  
Cell Division ◽  
Bacterial Cell ◽  
Large Scale ◽  
Bacterial Cell Division ◽  
Division Site ◽  
Associated Proteins ◽  
Z Ring ◽  
Cytoskeletal Networks ◽  
Cooperative Ordering

AbstractDuring bacterial cell division, the tubulin-homolog FtsZ forms a ring-like structure at the center of the cell. This Z-ring not only organizes the division machinery, but treadmilling of FtsZ filaments was also found to play a key role in distributing proteins at the division site. What regulates the architecture, dynamics and stability of the Z-ring is currently unknown, but FtsZ-associated proteins are known to play an important role. Here, using an in vitro reconstitution approach, we studied how the well-conserved protein ZapA affects FtsZ treadmilling and filament organization into large-scale patterns. Using high-resolution fluorescence microscopy and quantitative image analysis, we found that ZapA cooperatively increases the spatial order of the filament network, but binds only transiently to FtsZ filaments and has no effect on filament length and treadmilling velocity. Together, our data provides a model for how FtsZ-associated proteins can increase the precision and stability of the bacterial cell division machinery in a switch-like manner.

scholarly journals ZapE Is a Novel Cell Division Protein Interacting with FtsZ and Modulating the Z-Ring Dynamics

mBio ◽  
2014 ◽  
Vol 5 (2) ◽  
Author(s):  
Benoit S. Marteyn ◽  
Gouzel Karimova ◽  
Andrew K. Fenton ◽  
Anastasia D. Gazi ◽  
Nicholas West ◽  
...  
Keyword(s):  
Cell Division ◽  
Bacterial Cell ◽  
Dependent Manner ◽  
Bacterial Cell Division ◽  
Low Oxygen ◽  
Ftsz Ring ◽  
Division Process ◽  
Z Ring ◽  
Cell Division Protein

ABSTRACTBacterial cell division requires the formation of a mature divisome complex positioned at the midcell. The localization of the divisome complex is determined by the correct positioning, assembly, and constriction of the FtsZ ring (Z-ring). Z-ring constriction control remains poorly understood and (to some extent) controversial, probably due to the fact that this phenomenon is transient and controlled by numerous factors. Here, we characterize ZapE, a novel ATPase found in Gram-negative bacteria, which is required for growth under conditions of low oxygen, while loss ofzapEresults in temperature-dependent elongation of cell shape. We found that ZapE is recruited to the Z-ring during late stages of the cell division process and correlates with constriction of the Z-ring. Overexpression or inactivation ofzapEleads to elongation ofEscherichia coliand affects the dynamics of the Z-ring during division.In vitro, ZapE destabilizes FtsZ polymers in an ATP-dependent manner.IMPORTANCEBacterial cell division has mainly been characterizedin vitro. In this report, we could identify ZapE as a novel cell division protein which is not essentialin vitrobut is required during an infectious process. The bacterial cell division process relies on the assembly, positioning, and constriction of FtsZ ring (the so-called Z-ring). Among nonessential cell division proteins recently identified, ZapE is the first in which detection at the Z-ring correlates with its constriction. We demonstrate that ZapE abundance has to be tightly regulated to allow cell division to occur; absence or overexpression of ZapE leads to bacterial filamentation. AszapEis not essential, we speculate that additional Z-ring destabilizing proteins transiently recruited during late cell division process might be identified in the future.

scholarly journals Structure and Mutational Analyses of Escherichia coli ZapD Reveal Charged Residues Involved in FtsZ Filament Bundling

2016 ◽  
Vol 198 (11) ◽  
pp. 1683-1693 ◽  
Author(s):  
Elyse J. Roach ◽  
Charles Wroblewski ◽  
Laura Seidel ◽  
Alison M. Berezuk ◽  
Dyanne Brewer ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Cell Division ◽  
Bacterial Cell ◽  
Site Directed Mutagenesis ◽  
Bacterial Cell Division ◽  
Wild Type ◽  
Content Type ◽  
E Coli ◽  
Z Ring

ABSTRACTBacterial cell division is an essential and highly coordinated process. It requires the polymerization of the tubulin homologue FtsZ to form a dynamic ring (Z-ring) at midcell. Z-ring formation relies on a group of FtsZ-associatedproteins (Zap) for stability throughout the process of division. InEscherichia coli, there are currently five Zap proteins (ZapA through ZapE), of which four (ZapA, ZapB, ZapC, and ZapD) are small soluble proteins that act to bind and bundle FtsZ filaments. In particular, ZapD forms a functional dimer and interacts with the C-terminal tail of FtsZ, but little is known about its structure and mechanism of action. Here, we present the crystal structure ofEscherichia coliZapD and show it forms a symmetrical dimer with centrally located α-helices flanked by β-sheet domains. Based on the structure of ZapD and its chemical cross-linking to FtsZ, we targeted nine charged ZapD residues for modification by site-directed mutagenesis. Usingin vitroFtsZ sedimentation assays, we show that residues R56, R221, and R225 are important for bundling FtsZ filaments, while transmission electron microscopy revealed that altering these residues results in different FtsZ bundle morphology compared to those of filaments bundled with wild-type ZapD. ZapD residue R116 also showed altered FtsZ bundle morphology but levels of FtsZ bundling similar to that of wild-type ZapD. Together, these results reveal that ZapD residues R116, R221, and R225 likely participate in forming a positively charged binding pocket that is critical for bundling FtsZ filaments.IMPORTANCEZ-ring assembly underpins the formation of the essential cell division complex known as the divisome and is required for recruitment of downstream cell division proteins. ZapD is one of several proteins inE. colithat associates with the Z-ring to promote FtsZ bundling and aids in the overall fitness of the division process. In the present study, we describe the dimeric structure ofE. coliZapD and identify residues that are critical for FtsZ bundling. Together, these results advance our understanding about the formation and dynamics of the Z-ring prior to bacterial cell division.

scholarly journals A Novel Z-Ring Associated Protein ZapA-Like Protein (PA5407) From Pseudomonas aeruginosa Promotes FtsZ to Form Double Filaments

2021 ◽  
Vol 12 ◽  
Author(s):  
Xiaoyu Wang ◽  
Xueqin Ma ◽  
Zhe Li ◽  
Mingyue Niu ◽  
Meiting Zhai ◽  
...  
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Cell Division ◽  
Bacterial Cell ◽  
Regulatory Protein ◽  
Ring Structure ◽  
Bacterial Cell Division ◽  
Bacterial Division ◽  
Z Ring ◽  
Almost All

Bacterial cell division is initiated by the assembly of the contraction ring (Z-ring), which consists of the self-assembled FtsZ protofilaments and dozens of other associate proteins. ZapA, a regulatory protein found in almost all bacteria, stabilizes FtsZ protofilaments to form bundles and enhances the Z-ring condensation. Here, we reported that another small protein from Pseudomonas aeruginosa, ZapA-Like protein (ZapAL; PA5407), is a new FtsZ associated protein. ZapAL exists in many Pseudomonas species and shares only 20% sequence identity to ZapA. ZapAL interacts with FtsZ and induces FtsZ to form long straight double filaments; in comparison, ZapA promotes long bundles with multiple FtsZ filaments. ZapAL has only a mild effect on GTPase activity of FtsZ, which is reduced by around 26% when 10 μM ZapAL is added in the solution. However, to study their assembly dynamics using light-scattering assay, we found that FtsZ-ZapAL double filament is stable and no depolymerization process is observed, which is different from ZapA. Further research found that ZapA and ZapL are likely to form heterodimers. The bundles formed by the mixture of FtsZ-ZapA-ZapAL will depolymerize after GTP is hydrolyzed. Consistent with ZapAL interaction with FtsZ in vitro, the expression of ZapAL-GFP was observed as a narrow band or spots in the middle of the cells, suggesting that it is a component of bacterial division machinery. Similar to ZapA, ZapAL is also not essential for bacterial cell division. Little changes were observed when zapAL gene was deleted, or overexpressed under normal conditions; however, overexpression of ZapAL caused zapA-deficient cells to grow approximately two times longer, showing a mild bacterial division defect. Although we still do not know the exact physiological roles of ZapAL, our results suggest that ZapAL is a novel Z-ring associate protein, which may work together with ZapA to stabilize the FtsZ protofilament and Z-ring structure.

scholarly journals A conserved cell division protein directly regulates FtsZ dynamics in filamentous and unicellular actinobacteria

eLife ◽  
2021 ◽  
Vol 10 ◽  
Author(s):  
Félix Ramos-León ◽  
Matthew J Bush ◽  
Joseph W Sallmen ◽  
Govind Chandra ◽  
Jake Richardson ◽  
...  
Keyword(s):  
Cell Division ◽  
Bacterial Cell ◽  
Mycobacterium Smegmatis ◽  
Bacterial Cell Division ◽  
Z Ring ◽  
Cell Division Protein ◽  
Ring Architecture ◽  
Contractile Structure

Bacterial cell division is driven by the polymerization of the GTPase FtsZ into a contractile structure, the so-called Z-ring. This essential process involves proteins that modulate FtsZ dynamics and hence the overall Z-ring architecture. Actinobacteria like Streptomyces and Mycobacterium lack known key FtsZ-regulators. Here we report the identification of SepH, a conserved actinobacterial protein that directly regulates FtsZ dynamics. We show that SepH is crucially involved in cell division in Streptomyces venezuelae and that it binds FtsZ via a conserved helix-turn-helix motif, stimulating the assembly of FtsZ protofilaments. Comparative in vitro studies using the SepH homolog from Mycobacterium smegmatis further reveal that SepH can also bundle FtsZ protofilaments, indicating an additional Z-ring stabilizing function in vivo. We propose that SepH plays a crucial role at the onset of cytokinesis in actinobacteria by promoting the assembly of FtsZ filaments into division-competent Z-rings that can go on to mediate septum synthesis.

scholarly journals A conserved cell division protein directly regulates FtsZ dynamics in filamentous and unicellular actinobacteria

2020 ◽  
Author(s):  
Felix Ramos-Léon ◽  
Matthew J. Bush ◽  
Joseph W. Sallmen ◽  
Govind Chandra ◽  
Jake Richardson ◽  
...  
Keyword(s):  
Cell Division ◽  
Bacterial Cell ◽  
Crucial Role ◽  
Bacterial Cell Division ◽  
Z Ring ◽  
Cell Division Protein ◽  
Ring Architecture ◽  
Contractile Structure

AbstractBacterial cell division is driven by the polymerization of the GTPase FtsZ into a contractile structure, the so-called Z-ring. This essential process involves proteins that modulate FtsZ dynamics and hence the overall Z-ring architecture. Actinobacteria, like Streptomyces and Mycobacterium lack known key FtsZ-regulators. Here we report the identification of SepH, a conserved actinobacterial protein that directly regulates FtsZ dynamics. We show that SepH is crucially involved in cell division in Streptomyces and that it binds FtsZ via a conserved helix-turn-helix motif, stimulating the assembly of FtsZ protofilaments. Comparative in vitro studies using the SepH homolog from Mycobacterium further reveal that SepH can also bundle FtsZ protofilaments, indicating an additional Z-ring stabilizing function in vivo. We propose that SepH plays a crucial role at the onset of cytokinesis in actinobacteria by promoting the rapid assembly of FtsZ filaments into division-competent Z-rings that can go on to mediate septum synthesis.

scholarly journals In Vitro Reconstitution of the Initial Stages of the Bacterial Cell Division Machinery

2008 ◽  
Vol 34 (1-2) ◽  
pp. 237-247 ◽  
Author(s):  
Pilar López Navajas ◽  
Germán Rivas ◽  
Jesús Mingorance ◽  
Pablo Mateos-Gil ◽  
Ines Hörger ◽  
...  
Keyword(s):  
Cell Division ◽  
Bacterial Cell ◽  
Bacterial Cell Division ◽  
In Vitro Reconstitution

scholarly journals The key bacterial cell division protein FtsZ as a novel antibacterial drug target

2020 ◽  
Author(s):  
Mujeeb Rahman ◽  
Ping Wang ◽  
Na Wang ◽  
Yaodong Chen
Keyword(s):  
Cell Division ◽  
Bacterial Cell ◽  
Drug Targets ◽  
Multidrug Resistant ◽  
Antibacterial Drug ◽  
Bacterial Cell Division ◽  
Bacterial Strains ◽  
Antimicrobial Drugs ◽  
Novel Antibiotics

The number of multidrug-resistant bacterial strains is currently increasing; thus, the determination of drug targets for the development of novel antimicrobial drugs is urgently needed. FtsZ, the prokaryotic homolog of the eukaryotic tubulin, is a GTP-dependent prokaryotic cytoskeletal protein that is conserved among most bacterial strains. In vitro studies revealed that FtsZ self-assembles into dynamic protofilaments or bundles, and it forms a dynamic Z-ring at the center of the cell, leading to septation and consequent cell division. The potential role of FtsZ in the blockage of cell division makes FtsZ a highly attractive target for developing novel antibiotics. Researchers have been working on synthetic molecules and natural products as inhibitors of FtsZ. Accumulating data suggest that FtsZ may provide the platform for the development of novel antibiotics. In this review, we summarize recent advances on the properties of FtsZ protein and bacterial cell division, as well as on the development of FtsZ inhibitors.

scholarly journals Lateral interactions between protofilaments of the bacterial tubulin homolog FtsZ are essential for cell division

eLife ◽  
2018 ◽  
Vol 7 ◽  
Author(s):  
Fenghui Guan ◽  
Jiayu Yu ◽  
Jie Yu ◽  
Yang Liu ◽  
Ying Li ◽  
...  
Keyword(s):  
Cell Division ◽  
Bacterial Cell ◽  
Dynamic Structure ◽  
Living Cells ◽  
Lateral Interactions ◽  
Bacterial Cell Division ◽  
Z Ring ◽  
Crystallographic Structures ◽  
Order Structures

The prokaryotic tubulin homolog FtsZ polymerizes into protofilaments, which further assemble into higher-order structures at future division sites to form the Z-ring, a dynamic structure essential for bacterial cell division. The precise nature of interactions between FtsZ protofilaments that organize the Z-ring and their physiological significance remain enigmatic. In this study, we solved two crystallographic structures of a pair of FtsZ protofilaments, and demonstrated that they assemble in an antiparallel manner through the formation of two different inter-protofilament lateral interfaces. Our in vivo photocrosslinking studies confirmed that such lateral interactions occur in living cells, and disruption of the lateral interactions rendered cells unable to divide. The inherently weak lateral interactions enable FtsZ protofilaments to self-organize into a dynamic Z-ring. These results have fundamental implications for our understanding of bacterial cell division and for developing antibiotics that target this key process.

Sign in / Sign up

Export Citation Format

Share Document