Molecular mechanisms for the evolution of bacterial morphologies and growth modes

Randich, Amelia M.; Brun, Yves V.

doi:10.3389/fmicb.2015.00580

Cited by 72 publications

(71 citation statements)

References 130 publications

(169 reference statements)

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…This bacterium lacks both MinCD and NO systems to regulate the placement of the FtsZ ring. Instead it employs a ParA-like ATPase MipZ ( Mi dcell p ositioning of Fts Z ) to regulate the assembly site of the Z-ring (34, 111, 129). MipZ forms a gradient by interacting directly with origin-proximal DNA-bound ParB- parS complexes at the flagellated (stalked) pole prior to cell division and translocating with the newly replicated origin to the non-flagellated pole (Fig.…”

Section: Introductionmentioning

confidence: 99%

Bacterial Cell Division: Nonmodels Poised to Take the Spotlight

Eswara

Ramamurthi

2017

Annu. Rev. Microbiol.

View full text Add to dashboard Cite

The last three decades have witnessed an explosion in mechanistic details on how model bacterial organisms such as Escherichia coli, Bacillus subtilis, and Caulobacter crescentus undergo binary fission. These advances were possible by not only advances in microscopy that allowed cell biological questions to be answered, but also by the clever use of genetic manipulations in these systems in which specific hypothesis could be directly and easily tested. More recently, research using traditionally understudied organisms, or “non-model” systems, has revealed several alternate mechanistic strategies that bacteria use to divide and propagate. In this review, we will highlight these new findings and compare these strategies to cell division mechanisms elucidated in well-established model organisms.

show abstract

Section: Introductionmentioning

confidence: 99%

Bacterial Cell Division: Nonmodels Poised to Take the Spotlight

Eswara

Ramamurthi

2017

Annu. Rev. Microbiol.

View full text Add to dashboard Cite

show abstract

“…Thus, much research in the bacterial morphology field focuses on defining the mechanisms by which the cell wall is synthesized and modified to produce different cell body shapes. We refer the reader to several excellent reviews on cell wall synthesis and the evolution of bacterial morphogenesis for an in-depth consideration of this topic (6)(7)(8)(9). To summarize, studies in a variety of organisms have revealed that cell shape can be derived from asymmetric positioning of new cell wall synthesis, alteration of cell wall thickness, and/or changes in the chemical composition of the cell wall polymer or its extent of cross-linking.…”

Section: Cell Body Morphologymentioning

confidence: 99%

Staying in Shape: the Impact of Cell Shape on Bacterial Survival in Diverse Environments

Yang

Blair

Salama

2016

Microbiol Mol Biol Rev

245

192

View full text Add to dashboard Cite

SUMMARYBacteria display an abundance of cellular forms and can change shape during their life cycle. Many plausible models regarding the functional significance of cell morphology have emerged. A greater understanding of the genetic programs underpinning morphological variation in diverse bacterial groups, combined with assays of bacteria under conditions that mimic their varied natural environments, from flowing freshwater streams to diverse human body sites, provides new opportunities to probe the functional significance of cell shape. Here we explore shape diversity among bacteria, at the levels of cell geometry, size, and surface appendages (both placement and number), as it relates to survival in diverse environments. Cell shape in most bacteria is determined by the cell wall. A major challenge in this field has been deconvoluting the effects of differences in the chemical properties of the cell wall and the resulting cell shape perturbations on observed fitness changes. Still, such studies have begun to reveal the selective pressures that drive the diverse forms (or cell wall compositions) observed in mammalian pathogens and bacteria more generally, including efficient adherence to biotic and abiotic surfaces, survival under low-nutrient or stressful conditions, evasion of mammalian complement deposition, efficient dispersal through mucous barriers and tissues, and efficient nutrient acquisition.

show abstract

“…eptidoglycan (PG) biosynthesis and placement are dynamic processes that determine the shapes, sizes, chaining, and resistance to turgor of bacterial cells (1)(2)(3)(4)(5)(6). In Gram-positive bacteria, PG also serves as the scaffolding for covalent attachment of surface wall teichoic acid, capsule, and sortase-attached proteins (7)(8)(9).…”

mentioning

confidence: 99%

Minimal Peptidoglycan (PG) Turnover in Wild-Type and PG Hydrolase and Cell Division Mutants of Streptococcus pneumoniae D39 Growing Planktonically and in Host-Relevant Biofilms

et al. 2015

Self Cite

View full text Add to dashboard Cite

We determined whether there is turnover of the peptidoglycan (PG) cell wall of the ovococcus bacterial pathogen Streptococcus pneumoniae (pneumococcus). Pulse-chase experiments on serotype 2 strain D39 radiolabeled with N-acetylglucosamine revealed little turnover and release of PG breakdown products during growth compared to published reports of PG turnover in Bacillus subtilis. PG dynamics were visualized directly by long-pulse-chase-new-labeling experiments using two colors of fluorescent D-amino acid (FDAA) probes to microscopically detect regions of new PG synthesis. Consistent with minimal PG turnover, hemispherical regions of stable "old" PG persisted in D39 and TIGR4 (serotype 4) cells grown in rich brain heart infusion broth, in D39 cells grown in chemically defined medium containing glucose or galactose as the carbon source, and in D39 cells grown as biofilms on a layer of fixed human epithelial cells. In contrast, B. subtilis exhibited rapid sidewall PG turnover in similar FDAA-labeling experiments. High-performance liquid chromatography (HPLC) analysis of biochemically released peptides from S. pneumoniae PG validated that FDAAs incorporated at low levels into pentamer PG peptides and did not change the overall composition of PG peptides. PG dynamics were also visualized in mutants lacking PG hydrolases that mediate PG remodeling, cell separation, or autolysis and in cells lacking the MapZ and DivIVA division regulators. In all cases, hemispheres of stable old PG were maintained. In PG hydrolase mutants exhibiting aberrant division plane placement, FDAA labeling revealed patches of inert PG at turns and bulge points. We conclude that growing S. pneumoniae cells exhibit minimal PG turnover compared to the PG turnover in rod-shaped cells. IMPORTANCEPG cell walls are unique to eubacteria, and many bacterial species turn over and recycle their PG during growth, stress, colonization, and virulence. Consequently, PG breakdown products serve as signals for bacteria to induce antibiotic resistance and as activators of innate immune responses. S. pneumoniae is a commensal bacterium that colonizes the human nasopharynx and opportunistically causes serious respiratory and invasive diseases. The results presented here demonstrate a distinct demarcation between regions of old PG and regions of new PG synthesis and minimal turnover of PG in S. pneumoniae cells growing in culture or in host-relevant biofilms. These findings suggest that S. pneumoniae minimizes the release of PG breakdown products by turnover, which may contribute to evasion of the innate immune system. P eptidoglycan (PG) biosynthesis and placement are dynamic processes that determine the shapes, sizes, chaining, and resistance to turgor of bacterial cells (1-6). In Gram-positive bacteria, PG also serves as the scaffolding for covalent attachment of surface wall teichoic acid, capsule, and sortase-attached proteins (7-9). The seminal work of Park and Uehara demonstrated that PG is rapidly turned over and the breakdown components recycled in...

show abstract

Molecular mechanisms for the evolution of bacterial morphologies and growth modes

Cited by 72 publications

References 130 publications

Bacterial Cell Division: Nonmodels Poised to Take the Spotlight

Bacterial Cell Division: Nonmodels Poised to Take the Spotlight

Staying in Shape: the Impact of Cell Shape on Bacterial Survival in Diverse Environments

Minimal Peptidoglycan (PG) Turnover in Wild-Type and PG Hydrolase and Cell Division Mutants of Streptococcus pneumoniae D39 Growing Planktonically and in Host-Relevant Biofilms

Contact Info

Product

Resources

About