Microreviews
Toxin release mediated by the novel autolysin Cwp19 in Clostridium difficile
Imane El Meouche1 and Johann Peltier2,3
In this article, the authors comment on the study "Cwp19 is a novel lytic transglycosylase involved in stationary-phase autolysis resulting in toxin release in Clostridium difficile" by Wydau-Dematteis (MBio, 2018) that characterizes a novel peptidoglycan hydrolase, Cwp19, in Clostridioides difficile, highlighting its glucose-dependent mediation of toxins secretion and suggesting a potential role in the pathogenesis of this bacterium, contributing to the understanding of these enzymes in C. difficile and their implication in pathogenicity.
A global view of substrate phosphorylation and dephosphorylation during budding yeast mitotic exit
Sandra A. Touati1 and Frank Uhlmann1
In this article, the authors comment on the study "Phosphoproteome dynamics during mitotic exit in budding yeast" by Touati (EMBO J, 2018) that described a time-resolved global phosphoproteome analysis during a cell cycle phase known as mitotic exit in budding yeast revealed the principles of phosphoregulation governing the ordered sequence of events such as spindle elongation, chromosome decondensation, and completion of cell division.
Gammaretroviruses tether to mitotic chromatin by directly binding nucleosomal histone proteins
Madushi Wanaguru1 and Kate N. Bishop1
In this article, the authors comment on the study "Murine leukemia virus p12 tethers the capsid-containing pre-integration complex to chromatin by binding directly to host nucleosomes in mitosis" by Wanaguruet al. (PLoS Pathog, 2018) that highlights the essential role of the gammaretroviral gag cleavage product, p12, at both early and late stages of the virus life cycle, particularly in the integration of the viral DNA into the host cell chromatin to form a provirus. It also emphasizes the recent findings regarding the N- and C-terminal domains of p12, revealing their direct binding to the viral capsid lattice and nucleosomal histone proteins, respectively, thus elucidating the mechanism by which p12 links the viral pre-integration complex to mitotic chromatin.
Metabolic disharmony and sibling conflict mediated by T6SS
Vera Troselj1 and Daniel Wall1
In this article, the authors comment on the study "Physiological Heterogeneity Triggers Sibling Conflict Mediated by the Type VI Secretion System in an Aggregative Multicellular Bacterium" by Troselj et al. (MBio, 2018) discussing that M. xanthus uses T6SS to eliminate less fit cells from their population and identified toxic effector and cognate immunity protein (TsxEI) that mediates this sibling antagonism.
Helicobacter hepaticus polysaccharide induces an anti-inflammatory response in intestinal macrophages
Camille Danne1 and Fiona Powrie1
In this article, the authors comment on the study "A Large Polysaccharide Produced by Helicobacter hepaticus Induces an Anti-inflammatory Gene Signature in Macrophages. " by Danne et al, (Cell Host Microbe 2017), discussing the interactions between H. hepaticus and intestinal macrophages that promote mutualism.
Endolysosomal pathway activity protects cells from neurotoxic TDP-43
Christine Leibiger1,#, Jana Deisel1,#, Andreas Aufschnaiter2, Stefanie Ambros1, Maria Tereshchenko1, Bert M. Verheijen3,4, Sabrina Büttner2,5, and Ralf J. Braun1
In this article, the authors comment on the study "TDP-43 controls lysosomal pathways thereby determining its own clearance and cytotoxicity" by Leibiger et al. (Hum Mol Genet, 2018), proposing that ameliorating endolysosomal pathway activity enhances cell survival in TDP‑43-associated diseases.
Two distinct penicillin binding proteins promote cell division in different Salmonella lifestyles
Sónia Castanheira1, Juan J. Cestero1, Francisco García-del Portillo1, M. Graciela Pucciarelli1,2,3
In this article, the authors comment on the study "A Specialized Peptidoglycan Synthase Promotes Salmonella Cell Division inside Host Cells" by Castanheira et al. (mBio, 2017), discussing insights in two distinct penicillin binding proteins that promote cell division in different Salmonella lifestyles.
Cytokinins beyond plants: synthesis by Mycobacterium tuberculosis
May 4, 2015
This microreview discusses "Proteasomal Control of Cytokinin Synthesis Protects Mycobacterium tuberculosis against Nitric Oxide" by Samanovic et al. (2015), Mol Cell.
Yeast as a model system to study metabolic impact of selenium compounds
April 8, 2015
Inorganic Se forms such as selenate or selenite (the two more abundant forms in nature) can be toxic in Saccharomyces cerevisiae cells, which constitute an adequate model to study such toxicity at the molecular level and the functions participating in protection against Se compounds. In this article, the authors propose that yeast may be used to improve our knowledge on the impact of Se on metal homeostasis, the identification of Se-targets at the DNA and protein levels, and to gain more insights into the mechanism of Se-mediated apoptosis.
Understanding structure, function, and mutations in the mitochondrial ATP synthase
March 24, 2015
This review summarizes the current understanding of the subunit composition of the ATP synthase and the role of the subunits followed by a discussion on known mutations and their effect on the activity of the ATP synthase. The concludes with a summary of mutations in genes encoding subunits of the ATP synthase that are known to be responsible for human disease, and a brief discussion on SNPs.
Modeling non-hereditary mechanisms of Alzheimer disease during apoptosis in yeast
March 20, 2015
Impaired protein degradation and mitochondrial dysfunction are believed to contribute to neurodegenerative disorders, including Alzheimer disease (AD). This microreview comments on the article "Accumulation of Basic Amino Acids at Mitochondria Dictates the Cytotoxicity of Aberrant Ubiquitin" by Braun et al. (2015), Cell Rep.
Translate to divide: сontrol of the cell cycle by protein synthesis
March 20, 2015
Protein synthesis underpins much of cell growth and, consequently, cell multiplication. Understanding how proliferating cells commit and progress into the cell cycle requires knowing not only which proteins need to be synthesized, but also what determines their rate of synthesis during cell division. Experiments with proliferating populations of microbial strains, animal or plant cell lines, have rigorous expectations. Under the same culture conditions, cells ought to have the same properties and composition in every single experiment. The basic “metrics” of proliferating cells remain constant, even after many rounds of cell division. These metrics include cellular mass and volume, and macromolecular composition. The constancy of such parameters reflects the fundamental ability of cells to coordinate their growth with their division. Balancing cell growth with cell division determines the overall rates of cell proliferation...
New roles for autophagy and spermidine in T cells
March 2, 2015
This microreview discusses the article "Autophagy is a critical regulator of memory CD8+ T cell formation" by Puleston et al. (2014), eLife.
Characterization of the Maf family of polymorphic toxins in pathogenic Neisseria species
March 2, 2015
In addition to harmless commensal species, Neisseria genus encompasses two pathogenic species, N. meningitidis (the meningococcus) and N. gonorrhoeae (the gonococcus), which are responsible for meningitis and genital tract infections, respectively. This microreview comments on the article "A new family of secreted toxins in pathogenic Neisseria species" by Jamet et al. (2015), PLoS Pathog.
Live fast, die soon: cell cycle progression and lifespan in yeast cells
March 2, 2015
Our understanding of lifespan has benefited enormously from the study of a simple model, the yeast Saccharomyces cerevisiae. Although a unicellular organism, yeasts undergo many of the processes directly related with aging that to some extent are conserved in mammalian cells. Nutrient-limiting conditions have been involved in lifespan extension, especially in the case of caloric restriction, which also has a direct impact on cell cycle progression. In fact, other environmental stresses (osmotic, oxidative) that interfere with normal cell cycle progression also influence the lifespan of cells, indicating a relationship between lifespan and cell cycle control. In the present review we compile and discuss new findings related to how cell cycle progression is regulated by other nutrients. We centred this review on the analysis of phosphate, also give some attention to nitrogen, and the impact of these nutrients on lifespan...
Yeast as a tool for studying proteins of the Bcl-2 family
March 2, 2015
This review focuses on using yeast expressing mammalian proteins of the Bcl-2 family as a tool to investigate mechanisms, by which these proteins permeabilize mitochondrial membranes, mechanisms, by which pro- and antiapoptotic members of this family interact, and involvement of other cellular components in the regulation of programmed cell death by Bcl-2 family proteins.
Mitochondrial type II NAD(P)H dehydrogenases in fungal cell death
March 2, 2015
During aerobic respiration, cells produce energy through oxidative phosphorylation, which includes a specialized group of multi-subunit complexes in the inner mitochondrial membrane known as the electron transport chain. However, this canonical pathway is branched into single polypeptide alternative routes in some fungi, plants, protists and bacteria. They confer metabolic plasticity, allowing cells to adapt to different environmental conditions and stresses...