Vol. 05, 2018

pH homeostasis links the nutrient sensing PKA/TORC1/Sch9 ménage-à-trois to stress tolerance and longevity

Marie-Anne Deprez^1,°, Elja Eskes^1,°, Tobias Wilms¹, Paula Ludovico², Joris Winderickx¹

In this article, Deprez et al. discuss accumulating evidence indicates that pH homeostasis plays a prominent role in the determination of ageing and longevity, thereby providing new perspectives and avenues to explore the underlying molecular mechanisms.

Guidelines and recommendations on yeast cell death nomenclature

Didac Carmona-Gutierrez^1,‡,*, Maria Anna Bauer^1,‡, Andreas Zimmermann¹, Andrés Aguilera², Nicanor Austriaco³, Kathryn Ayscough⁴, Rena Balzan⁵, Shoshana Bar-Nun⁶, Antonio Barrientos^7,8, Peter Belenky⁹, Marc Blondel¹⁰, Ralf J. Braun¹¹, Michael Breitenbach¹², William C. Burhans¹³, Sabrina Büttner^1,14, Duccio Cavalieri¹⁵, Michael Chang¹⁶, Katrina F. Cooper¹⁷, Manuela Côrte-Real¹⁸, Vítor Costa^19–21, Christophe Cullin²², Ian Dawes²³, Jörn Dengjel²⁴, Martin B. Dickman²⁵, Tobias Eisenberg^1,26, Birthe Fahrenkrog²⁷, Nicolas Fasel²⁸, Kai-Uwe Fröhlich¹, Ali Gargouri²⁹, Sergio Giannattasio³⁰, Paola Goffrini³¹, Campbell W. Gourlay³², Chris M. Grant³³, Michael T. Greenwood³⁴, Nicoletta Guaragnella³⁰, Thomas Heger³⁵, Jürgen Heinisch³⁶, Eva Herker³⁷, Johannes M. Herrmann³⁸, Sebastian Hofer¹, Antonio Jiménez-Ruiz³⁹, Helmut Jungwirth¹, Katharina Kainz¹, Dimitrios P. Kontoyiannis⁴⁰, Paula Ludovico^41,42, Stéphen Manon⁴³, Enzo Martegani⁴⁴, Cristina Mazzoni⁴⁵, Lynn A. Megeney^46–48, Chris Meisinger⁴⁹, Jens Nielsen^50–52, Thomas Nyström⁵³, Heinz D. Osiewacz⁵⁴, Tiago F. Outeiro^55–58, Hay-Oak Park⁵⁹, Tobias Pendl¹, Dina Petranovic^50,51, Stephane Picot^60,61, Peter Polčic⁶², Ted Powers⁶³, Mark Ramsdale⁶⁴, Mark Rinnerthaler⁶⁵, Patrick Rockenfeller^1,32, Christoph Ruckenstuhl¹, Raffael Schaffrath⁶⁶, Maria Segovia⁶⁷, Fedor F. Severin⁶⁸, Amir Sharon⁶⁹, Stephan J. Sigrist⁷⁰, Cornelia Sommer-Ruck¹, Maria João Sousa¹⁸, Johan M. Thevelein^71,72, Karin Thevissen⁷³, Vladimir Titorenko⁷⁴, Michel B. Toledano⁷⁵, Mick Tuite³², F.-Nora Vögtle⁴⁹, Benedikt Westermann¹¹, Joris Winderickx⁷⁶, Silke Wissing⁷⁷, Stefan Wölfl⁷⁸, Zhaojie J. Zhang⁷⁹, Richard Y. Zhao⁸⁰, Bing Zhou⁸¹, Lorenzo Galluzzi^82–84,*, Guido Kroemer^84–90,*, Frank Madeo^1,26,*

In this review, we propose unified criteria for the definition of accidental, regulated, and programmed forms of cell death in yeast based on a series of morphological and biochemical criteria. Specifically, we provide consensus guidelines on the differential definition of terms including apoptosis, regulated necrosis, and autophagic cell death, as we refer to additional cell death routines that are relevant for the biology of yeast.

Burkholderia gladioli strain NGJ1 deploys a prophage tail-like protein for mycophagy

Rahul Kumar¹, Sunil Kumar Yadav¹, Durga Madhab Swain¹ and Gopaljee Jha¹

In this article, the authors comment on the study "A prophage tail-like protein is deployed by Burkholderia bacteria to feed on fungi" by Swain et al. (Nature Communications, 2017), discussing that a prophage tail-like protein (Bg_9562) is essential for mycophagy. The protein may help the bacteria to survive in certain ecological niches and, considering its broad-spectrum antifungal activity, may be potentially useful in biotechnological applications to control fungal diseases.

Fat storage-inducing transmembrane (FIT or FITM) proteins are related to lipid phosphatase/phosphotransferase enzymes

Matthew J Hayes¹, Vineet Choudhary², Namrata Ojha², John JH Shin³, Gil-Soo Han⁴, George M. Carman⁴, Christopher JR Loewen³, William A Prinz² and Timothy P Levine¹

Fat storage-inducing transmembrane (FIT or FITM) proteins have been implicated in the partitioning of triacylglycerol to lipid droplets and the budding of lipid droplets from the ER. Saccharomyces cerevisiae has two FITM homologues and the presented results suggest that Scs3p and Yft2p as well as FITMs in general are lipid phosphatase/phosphotransferase (LPT) enzymes involved in an as yet unknown critical step in phospholipid metabolism.

Ras signalling in pathogenic yeasts

Daniel R. Pentland¹, Elliot Piper-Brown¹, Fritz A. Mühlschlegel^1,2 and Campbell W. Gourlay¹

In this article Pentland et al. review the roles of Ras protein function and signalling in the major human yeast pathogens Candida albicans and Cryptococcus neoformans and discuss the potential for targeting Ras as a novel approach to anti-fungal therapy.

The logics of metabolic regulation in bacteria challenges biosensor-based metabolic engineering

Matthieu Jules¹

In this article, the authors comment on the study "Molecular and Physiological Logics of the Pyruvate-Induced Response of a Novel Transporter in Bacillus subtilis" by Charbonnier et al. (mBio, 2017), which identified and characterized a pyruvate transport system in the Gram-positive (G+ve) bacterium Bacillus subtilis, a well-established biotechnological workhorse for the production of enzymes, fine chemicals and antibiotics.

A novel basolateral type IV secretion model for the CagA oncoprotein of Helicobacter pylori

Silja Wessler¹ and Steffen Backert²

In this article, the authors comment on the study "Helicobacter pylori Employs a Unique Basolateral Type IV Secretion Mechanism for CagA Delivery" by Tegtmeyer et al. (Cell Host Microbe, 2017), discussing that the finding of a T4SS receptor suggests the presence of a sophisticated control mechanism for the injection of CagA and the possible impact of this novel signaling cascade on pathogenesis during infection with Helicobacter pylori.

Yeast quiescence exit swiftness is influenced by cell volume and chronological age

Damien Laporte¹, Laure Jimenez¹, Laëtitia Gouleme¹, Isabelle Sagot¹

Quiescence exit swiftness is crucial not only for micro-organisms in competition for an environmental niche, such as yeast, but also for the maintenance of tissue homeostasis in multicellular species. Here, Laporte et al. explore the effect of replicative and chronological age on Saccharomyces cerevisiae quiescence exit efficiency. Overall, their data illustrate that the quiescent state is a continuum evolving with time, early and deep quiescence being distinguishable by the cell’s proficiency to re-enter the proliferation cycle.

Exploring the mechanism of amebic trogocytosis: the role of amebic lysosomes

Allissia A. Gilmartin¹ and William A. Petri, Jr^1,2,3

In this article, the authors comment on the study "Inhibition of Amebic Lysosomal Acidification Blocks Amebic Trogocytosis and Cell Killing" by Gilmartin et al. (MBio, 2017), discussing the the role of amebic lysosomes in Trogocytosis, the intracellular transfer of fragments of cell material.

Previous Next

Shepherding DNA ends: Rif1 protects telomeres and chromosome breaks

Gabriele A. Fontana¹, Julia K. Reinert^1,2, Nicolas H. Thomä¹, Ulrich Rass¹

This review discusses the conserved mechanisms cells have evolved to protect DNA ends at chromosomal termini and DNA double-strand breaks (DSBs), focusing on the protein Rif1’s roles in telomere homeostasis and DSB repair in eukaryotes. It highlights the intriguing connection between Rif1's involvement in both telomere maintenance and DSB repair, and suggests that excluding end-processing factors may underlie Rif1's diverse biological functions at telomeres and chromosome breaks.

The CRISPR conundrum: evolve and maybe die, or survive and risk stagnation

Jesús García-Martínez¹, Rafael D. Maldonado¹, Noemí M. Guzmán¹ and Francisco J. M. Mojica^1,2

In this article García-Martínez et al. cover how the model bacterium Escherichia coli deals with CRISPR-Cas to tackle the major dilemma of evolution versus survival.

Microbial wars: competition in ecological niches and within the microbiome

Maria A. Bauer¹, Katharina Kainz¹, Didac Carmona-Gutierrez¹ and Frank Madeo^1,2

In this Editorial Bauer et al. provide a brief overview on microbial competition and discuss some of its roles and consequences that directly affect humans.

A novel mechanism for regulation of the type I IFN response by herpesvirus deconjugases

Soham Gupta¹, Päivi Ylä-Anttila¹, Maria G. Masucci¹

In this article, the authors comment on the study "Herpesvirus deconjugases inhibit the IFN response by promoting TRIM25 autoubiquitination and functional inactivation of the RIG-I signalosome" by Gupta et al. (PLoS Pathog, 2018), discussing the finding of a novel mechanism for regulation of the type I IFN response by herpesvirus deconjugases.

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.

Antagonism between salicylate and the cAMP signal controls yeast cell survival and growth recovery from quiescence

Maurizio D. Baroni¹, Sonia Colombo² and Enzo Martegani²

This article describes the effects of salicylate, the main metabolite of aspirin, on S. cerevisiae cells. It outlines how salicylate influences glucose transport, sugar phosphate biosynthesis, and apoptosis, particularly in MnSOD-deficient cells. Furthermore, it emphasizes the significant impact of salicylate on the exit from a quiescent state, inhibiting growth recovery and viability in long-term stationary phase cells. The passage also discusses the potential therapeutic implications of understanding the antagonistic relationship between cAMP and salicylate in targeting quiescent cancer cells with stem-like properties.

Previous Next

Retroviral integration site selection: a running Gag?

Paul Lesbats^1,2,3 and Vincent Parissi^1,2,3

In this article, the authors comment on the study "Structural basis for spumavirus GAG tethering to chromatin" by Lesbats et al. (Proc Natl Acad Sci, 2018) that revealed that the Gag protein of the spumaretrovirus prototype foamy virus (PFV) directly interacts with the nucleosome acidic patch, acting as a chromatin tether, and its disruption leads to delocalization of viral particles and integration sites, shedding light on the importance of retroviral structural proteins in the selection of integration sites.

Insights into the host-pathogen interaction: C. albicans manipulation of macrophage pyroptosis

Teresa R. O’Meara¹ and Leah E. Cowen¹

In this article, the authors comment on the study "High-Throughput Screening Identifies Genes Required for Candida albicans Induction of Macrophage Pyroptosis" by O’Meara et al. (MBio, 2018) that provides a comprehensive analysis of the genetic circuitry in both Candida albicans and host macrophages that leads to pyroptosis, revealing the impact of altered pyroptosis on infection, the role of pyroptosis in facilitating neutrophil accumulation at the site of C. albicans infection, and the decoupling of inflammasome priming and activation in the response to C. albicans infection, thus shedding new light on the factors governing the outcomes of this interaction.

A comparative approach to decipher intestinal animal-microbe associations

Keisuke Nakashima¹

In this article, the authors comment on the study "Chitin-based barrier immunity and its loss predated mucus-colonization by indigenous gut microbiota" by Nakashima et al. (Nat Commun, 2018) that used comparative analyses of chordates to investigate the development of animal-microbe associations, suggesting that microbial colonization of the mucus layer over mammalian gastrointestinal epithelium was established upon the loss of ancestral chitin-based barrier immunity, providing insights into the establishment of these associations in an evolutionary context.

Pathways of host cell exit by intracellular pathogens

Antje Flieger^1,#, Freddy Frischknecht², Georg Häcker³, Mathias W. Hornef⁴, Gabriele Pradel⁵

This review provides an overview of the diverse host cell exit strategies employed by intracellular-living bacterial, fungal, and protozoan pathogens, highlighting the commonalities and system-specific variations of these strategies, and discussing potential microbial molecules involved in host cell exit as targets for future intervention approaches.

Conventional and emerging roles of the energy sensor Snf1/AMPK in Saccharomyces cerevisiae

Paola Coccetti^1,2, Raffaele Nicastro^1,3 and Farida Tripodi^1,2

This review consolidates current knowledge on the conventional and non-conventional functions of the effector kinase Snf1 in yeast, shedding light on its diverse roles in cellular physiology and energy homeostasis.

An unexpected benefit from E. coli: how enterobactin benefits host health

Aileen K. Sewell^1,2, Min Han^1,2 and Bin Qi^1,2

In this article, the authors comment on the study "Microbial Siderophore Enterobactin Promotes Mitochondrial Iron Uptake and Development of the Host via Interaction with ATP Synthase" by Qi et al. (Cell, 2018) that uncovered a surprising role for the Escherichia coli-produced siderophore enterobactin (Ent) in facilitating iron uptake by the host, marking a major shift in the understanding of its function and indicating potential new benefits from commensal bacteria in aiding the host's iron homeostasis.

Protective roles of ginseng against bacterial infection

Ye-Ram Kim¹ and Chul-Su Yang¹

This review highlights the antibacterial effects of ginseng against pathogenic bacterial infections, discussing its regulation of pathogenic factors and proposing the therapeutic potential of ginseng as a natural antibacterial drug to address antibiotic resistance and toxicity in the context of global public health challenges.

A Cinderella story: how the vacuolar proteases Pep4 and Prb1 do more than cleaning up the cell’s mass degradation processes

Winnie Kerstens^1,2 and Patrick Van Dijck^1,2

This review summarizes the expanded roles of the Saccharomyces cerevisiae vacuolar proteases Pep4 and Prb1 in non-vacuolar activities outside of autophagy, such as programmed cell death, protection from harmful protein forms, and gene expression regulation. The potential implications of these findings for fungal biology and drug target discovery, including insights for mammalian cell studies, are highlighted, emphasizing the need for a deeper understanding of these molecular processes.

The biosynthesis of pyoverdines

Michael T. Ringel¹ and Thomas Brüser¹

This review provides an overview of pyoverdine biosynthesis, emphasizing the distinctive fluorophore shared by various pyoverdines derived from ferribactins and the role of periplasmic processes in the maturation and modification of these siderophores, critical for the growth and colonization of hosts by fluorescent pseudomonads.

Microbial wars: competition in ecological niches and within the microbiome

Maria A. Bauer¹, Katharina Kainz¹, Didac Carmona-Gutierrez¹ and Frank Madeo^1,2

In this Editorial Bauer et al. provide a brief overview on microbial competition and discuss some of its roles and consequences that directly affect humans.

Exploring the mechanism of amebic trogocytosis: the role of amebic lysosomes

Allissia A. Gilmartin¹ and William A. Petri, Jr^1,2,3

Gammaretroviruses tether to mitotic chromatin by directly binding nucleosomal histone proteins

July 24, 2018

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.

Snf1 cooperates with the CWI MAPK pathway to mediate the degradation of Med13 following oxidative stress

June 25, 2018

This article explores the response of eukaryotic cells to environmental stress, highlighting the role of the conserved cyclin C-Cdk8 kinase in determining pro-survival or pro-death programs. Specifically, it discusses how oxidative stress triggers the destruction of Med13 by the SCFGrr1 ubiquitin ligase, releasing cyclin C to promote mitochondrial fission and cell death in Saccharomyces cerevisiae. Additionally, it reveals that the AMP kinase Snf1 activates a separate degron in Med13, contributing to the complex regulation of Med13 degradation following H2O2 stress through the coordination of the cell wall integrity and MAPK pathways.

Importance of polyphosphate in the Leishmania life cycle

June 22, 2018

This article explores the importance of polyphosphate (polyP) in Leishmania parasites, emphasizing the role of the polyP polymerase VTC4 and its impact on parasite survival at higher temperatures. Additionally, it discusses the effects of VTC4 knockout in mouse infections, noting a delay in lesion formation and strong pathology in L. major VTC4 knockout, without confirmation through complementation and no alteration in L. guyanensis infections in mice with VTC4 knockdown.

Methodologies for in vitro and in vivo evaluation of efficacy of antifungal and antibiofilm agents and surface coatings against fungal biofilms

June 14, 2018

This article highlights the critical importance of accurate susceptibility testing methods and the discovery of novel antifungal and antibiofilm agents in combating invasive fungal infections associated with biofilm formation on medical devices, thereby emphasizing the need for advancements in medical mycology research to address these complex diseases.