Vol. 05, 2018
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.
Evolution of substrate specificity in the Nucleobase-Ascorbate Transporter (NAT) protein family
Anezia Kourkoulou1,#, Alexandros A. Pittis2,# and George Diallinas1
L-ascorbic acid (vitamin C) is an essential metabolite in animals and plants due to its role as an enzyme co-factor and antioxidant activity. Here, Kourkoulou et al. show further evidence that ascorbate-specific Nucleobase-Ascorbate Transporters (NATs) evolved by optimization of a sub-function of ancestral nucleobase transporters.
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.
Valine biosynthesis in Saccharomyces cerevisiae is regulated by the mitochondrial branched-chain amino acid aminotransferase Bat1
Natthaporn Takpho1, Daisuke Watanabe1 and Hiroshi Takagi1
In Saccharomyces cerevisiae, the yeast, the Bat1 and Bat2 proteins, which are branched-chain amino acid aminotransferases, play distinct roles in valine biosynthesis and cell growth regulation, with Bat1 primarily located in the mitochondria and Bat2 in the cytosol, and the mitochondria being identified as the major site of valine biosynthesis in this yeast.
Microbial competition between Escherichia coli and Candida albicans reveals a soluble fungicidal factor
Damien J. Cabral1, Swathi Penumutchu1, Colby Norris1,2, Jose Ruben Morones-Ramirez3,4 and Peter Belenky1
Localized and systemic fungal infections caused by Candida albicans can lead to significant mortality and morbidity. Here, Cabral et al. show that E. coli produces a soluble factor that kills C. albicans in a magnesium-dependent fashion such that depletion of available magnesium is essential for toxicity.
Spontaneous mutations in CYC8 and MIG1 suppress the short chronological lifespan of budding yeast lacking SNF1/AMPK
Nazif Maqani1,#, Ryan D. Fine1,#, Mehreen Shahid1, Mingguang Li1,2, Elisa Enriquez-Hesles1 and Jeffrey S. Smith1
Chronologically aging yeast cells are prone to adaptive regrowth, whereby mutants with a survival advantage spontaneously appear and re-enter the cell cycle in stationary phase cultures. Here, Magani et al. identified specific downstream SNF1 targets responsible for CLS extension during CR.
Molecular signature of the imprintosome complex at the mating-type locus in fission yeast
Célia Raimondi1, Bernd Jagla2, Caroline Proux3, Hervé Waxin4, Serge Gangloff1, Benoit Arcangioli1
Genetic and molecular studies have indicated that an epigenetic imprint at mat1, the sexual locus of fission yeast, initiates mating type switching. Here, Raimondi et al. characterized the recruitment of early players of mating type switching at the mat1 region and suggest a nucleoprotein protective structure defined as imprintosome.
A novel system to monitor mitochondrial translation in yeast
Tamara Suhm1, Lukas Habernig2, Magdalena Rzepka1, Jayasankar Mohanakrishnan Kaimal3, Claes Andréasson3, Sabrina Büttner2,3 and Martin Ott1
In this study Suhm et al. present a novel system to monitor mitochondrial translation by detection of mitochondrial GFP-translation through fluorescence microscopy and flow cytometry in functional mitochondria. This novel tool allows the investigation of the function and regulation of mitochondrial translation during stress signaling, aging and mitochondrial biogenesis.
pH homeostasis links the nutrient sensing PKA/TORC1/Sch9 ménage-à-trois to stress tolerance and longevity
Marie-Anne Deprez1,°, Elja Eskes1,°, 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-Gutierrez1,‡,*, Maria Anna Bauer1,‡, Andreas Zimmermann1, Andrés Aguilera2, Nicanor Austriaco3, Kathryn Ayscough4, Rena Balzan5, Shoshana Bar-Nun6, Antonio Barrientos7,8, Peter Belenky9, Marc Blondel10, Ralf J. Braun11, Michael Breitenbach12, William C. Burhans13, Sabrina Büttner1,14, Duccio Cavalieri15, Michael Chang16, Katrina F. Cooper17, Manuela Côrte-Real18, Vítor Costa19–21, Christophe Cullin22, Ian Dawes23, Jörn Dengjel24, Martin B. Dickman25, Tobias Eisenberg1,26, 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 Ludovico41,42, Stéphen Manon43, Enzo Martegani44, Cristina Mazzoni45, Lynn A. Megeney46–48, Chris Meisinger49, Jens Nielsen50–52, Thomas Nyström53, Heinz D. Osiewacz54, Tiago F. Outeiro55–58, Hay-Oak Park59, Tobias Pendl1, Dina Petranovic50,51, Stephane Picot60,61, Peter Polčic62, Ted Powers63, Mark Ramsdale64, Mark Rinnerthaler65, Patrick Rockenfeller1,32, Christoph Ruckenstuhl1, Raffael Schaffrath66, Maria Segovia67, Fedor F. Severin68, Amir Sharon69, Stephan J. Sigrist70, Cornelia Sommer-Ruck1, Maria João Sousa18, Johan M. Thevelein71,72, 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 Galluzzi82–84,*, Guido Kroemer84–90,*, Frank Madeo1,26,*
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.
Retroviral integration site selection: a running Gag?
Paul Lesbats1,2,3 and Vincent Parissi1,2,3
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 Flieger1,#, 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.
An unexpected benefit from E. coli: how enterobactin benefits host health
Aileen K. Sewell1,2, Min Han1,2 and Bin Qi1,2
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 Kerstens1,2 and Patrick Van Dijck1,2
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.
Exploring the mechanism of amebic trogocytosis: the role of amebic lysosomes
Allissia A. Gilmartin1 and William A. Petri, Jr1,2,3
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.
Evolution of substrate specificity in the Nucleobase-Ascorbate Transporter (NAT) protein family
March 22, 2018
L-ascorbic acid (vitamin C) is an essential metabolite in animals and plants due to its role as an enzyme co-factor and antioxidant activity. Here, Kourkoulou et al. show further evidence that ascorbate-specific Nucleobase-Ascorbate Transporters (NATs) evolved by optimization of a sub-function of ancestral nucleobase transporters.
Helicobacter hepaticus polysaccharide induces an anti-inflammatory response in intestinal macrophages
March 22, 2018
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
March 21, 2018
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.
Valine biosynthesis in Saccharomyces cerevisiae is regulated by the mitochondrial branched-chain amino acid aminotransferase Bat1
March 21, 2018
In Saccharomyces cerevisiae, the yeast, the Bat1 and Bat2 proteins, which are branched-chain amino acid aminotransferases, play distinct roles in valine biosynthesis and cell growth regulation, with Bat1 primarily located in the mitochondria and Bat2 in the cytosol, and the mitochondria being identified as the major site of valine biosynthesis in this yeast.
Microbial competition between Escherichia coli and Candida albicans reveals a soluble fungicidal factor
March 7, 2018
Localized and systemic fungal infections caused by Candida albicans can lead to significant mortality and morbidity. Here, Cabral et al. show that E. coli produces a soluble factor that kills C. albicans in a magnesium-dependent fashion such that depletion of available magnesium is essential for toxicity.
Spontaneous mutations in CYC8 and MIG1 suppress the short chronological lifespan of budding yeast lacking SNF1/AMPK
February 19, 2018
Chronologically aging yeast cells are prone to adaptive regrowth, whereby mutants with a survival advantage spontaneously appear and re-enter the cell cycle in stationary phase cultures. Here, Magani et al. identified specific downstream SNF1 targets responsible for CLS extension during CR.
Two distinct penicillin binding proteins promote cell division in different Salmonella lifestyles
February 18, 2018
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.
Production of poly-β-1,6-N-acetylglucosamine by MatAB is required for hyphal aggregation and hydrophilic surface adhesion by Streptomyces
February 12, 2018
In this article van Dissel et al. describe new insights to allow better control of liquid-culture morphology of streptomycetes, which may be harnessed to improve growth and industrial exploitation of these highly versatile natural product and enzyme producers.
Impact of F1Fo-ATP-synthase dimer assembly factors on mitochondrial function and organismic aging
January 30, 2018
In aerobic organisms, mitochondrial F1Fo-ATP-synthase is the major site of ATP production. Here, Rampello et al. report on the role of the two dimer assembly factors PaATPE and PaATPG of the aging model Podospora anserina validating a model that links mitochondrial membrane remodeling to aging and identify specific molecular components triggering this process.
Microbial wars: competition in ecological niches and within the microbiome
Maria A. Bauer1, Katharina Kainz1, Didac Carmona-Gutierrez1 and Frank Madeo1,2
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.