Vol. 04, 2017
Toxin-mediated gene regulatory mechanism in Staphylococcus aureus
Hwang-Soo Joo and Michael Otto
This article comments on work published by Joo et al. (MBio, 2016), which describes the first molecular regulatory mechanism exerted by an S. aureus toxin, setting a paradigmatic example of how S. aureus toxins may influence cell functions to adjust them to times of toxin production.
Improvement of biochemical methods of polyP quantification
Samuel Bru1, Javier Jiménez1, David Canadell2,#, Joaquín Ariño2, Josep Clotet1
As the main output of this evaluation we propose a straightforward and robust procedure that can be used as gold standard protocol for cellular polyP purification and determination from unicellular organisms, thus providing consistency to measurements and facilitating inter-laboratory comparisons and biological interpretation of the results.
Breaking the bilayer: OMV formation during environmental transitions
Katherine E. Bonnington, Meta J. Kuehn
This article comments on work published by Bonnington & Kuehn (MBio, 2016), which shows how gram-negative bacteria maintain the barrier properties of the outer membrane (OM) in a wide array of physiological conditions despite their inability to degrade lipopolysaccharide (LPS) and protein material present in the outer leaflet of the OM.
Mutational analysis of fructose-1,6-bis-phosphatase FBP1 indicates partially independent functions in gluconeogenesis and sensitivity to genotoxic stress
Ali Ghanem, Ana Kitanovic, Jinda Holzwarth, Stefan Wölfl
Our results support predicted vital roles of several fructose-1,6-bisphosphatase residues for enzymatic activity and led to the identification of residues indispensable for the MMS-sensitizing effect. Despite an overlap between these two properties, careful analysis revealed two mutations, Asn75 and His324, which decouple the enzymatic activity and the MMS-sensitizing effect, indicating two distinctive biological activities linked in this key gluconeogenesis enzyme.
The tug-of-war over MTOR in Legionella infections
Stanimir S. Ivanov
This article comments on work published by Abshire et al (PLoS Pathog, 2016), which uncovered that the host metabolic checkpoint kinase Mechanistic target of rapamycin (MTOR) is a central regulator of the pathogen niche expansion program.
A new role for Holliday junction resolvase Yen1 in processing DNA replication intermediates exposes Dna2 as an accessory replicative helicase
Benoît Falquet1,2 and Ulrich Rass
This article comments on work published by Ölmezer et al. (Nat Commun, 2016), which revealed a new function of Yen1, distinct from its previously known role as a Holliday junction resolvase, mediating the removal of branched HR intermediates.
The copper transport-associated protein Ctr4 can form prion-like epigenetic determinants in Schizosaccharomyces pombe
Theodora Sideri1, Yoko Yashiroda2, David A. Ellis1, María Rodríguez-López1, Minoru Yoshida2, Mick F. Tuite3 & Jürg Bähler1
Ctr4 exhibits multiple features diagnostic of other fungal prions and is the first example of a prion in fission yeast. These findings suggest that transmissible protein-based determinants of traits may be more widespread among fungi.
Using microbes as a key tool to unravel the mechanism of autophagy and the functions of the ATG proteins
Mario Mauthe1,2 and Fulvio Reggiori1,2
Microbes have served to discover and characterize unconventional functions of the ATG proteins, which are uncoupled from their role in autophagy. In our recent study, we have taken advantage of viruses as a screening tool to determine the extent of the unconventional functions of the ATG proteome and characterize one of them.
Live fast, die fast principle in a single cell of fission yeast
Hidenori Nakaoka1
This article comments on a recent study (Nakaoka and Wakamoto, PLoS Biol, 2017), which developed a microfluidics-based platform to track multiple single cell lineages until death.
Out with the old: Hsp90 finds amino acid residue more useful than co-chaperone protein
Abbey D. Zuehlke1 and Leonard Neckers1
This article comments on work published by Zuehlke et al (Nat Commun, 2017), which demonstrates that the function of one co-chaperone in yeast is replaced by posttranslational modification (PTM) of a single amino acid within Hsp90 in higher eukaryotes.
Having your cake and eating it – Staphylococcus aureus small colony variants can evolve faster growth rate without losing their antibiotic resistance
Gerrit Brandis1, Sha Cao1, Douglas L. Huseby1 and Diarmaid Hughes1
This article comments on work published by Cao et al. (mBio, 2027), which shows that Staphylococcus aureus can produce small colony variants (SCVs) that are challenging to detect and lead to persistent infections due to mutations affecting respiration and ATP production, with recent findings indicating various evolutionary paths for SCVs to increase growth rate while maintaining antibiotic resistance, suggesting greater adaptability and clinical challenge.
The interplay between transcription and mRNA degradation in Saccharomyces cerevisiae
Subhadeep Das1, Debasish Sarkar2 and Biswadip Das1
This review summarizes how the integration of mRNA synthesis and degradation, mediated by specialized promoters and "coordinators," shapes the cellular transcriptome and plays a significant role in regulating gene expression profiles in various biological processes and potentially enhances evolutionary rates.
Inhibitors of glycosomal protein import provide new leads against trypanosomiasis
Vishal C. Kalel1, Leonidas Emmanouilidis2,3, Maciej Dawidowski2,3,4, Wolfgang Schliebs1, Michael Sattler2,3, Grzegorz M. Popowicz2,3, Ralf Erdmann1
This article comments on work published by Dawidowski et al. (Science, 2017), which provides the grounds for further development of the glycosome inhibitors into clinical candidates and validates the parasite protein-protein interactions as drug targets.
Protein aggregation triggers a declining libido in elder yeasts that still have a lust for life
Fabrice Caudron
This article comments on work published by Schlissel et al (Science 2017), showing that aging in yeast does not lead to the expected loss of heterochromatin silencing due to Sir2 inactivity, but rather to reduced mating pheromone sensitivity caused by the aggregation of the RNA-binding protein Whi3, which can be reversed by eliminating Whi3's polyglutamine domain.
The Yin & Yang of Mitochondrial Architecture – Interplay of MICOS and F1Fo-ATP synthase in cristae formation
Heike Rampelt1 and Martin van der Laan2
This Editorial posits that mitochondrial cristae architecture is shaped by the interplay of MICOS and ATP synthase, with a recent study illuminating their roles in cristae formation and maintenance.
When a ribosomal protein grows up – the ribosome assembly path of Rps3
Brigitte Pertschy
This article comments on two papers by Mitterer et al., which followed yeast protein Rps3, highlighting the sophisticated mechanisms for protein protection, nuclear transport, and integration into pre-ribosomal particles for final assembly with 40S subunits.
Staphylococcus aureus type I signal peptidase: essential or not essential, that’s the question
Wouter L.W. Hazenbos1, Elizabeth Skippington2 and Man-Wah Tan1
This article comments on work published by Morisaki et al. (mBio, 2016), which characterized a novel ABC transporter. This transporter apparently compensates for SpsB’s essential function by mediating alternative cleavage of a subset of proteins at a site distinct from the SpsB-cleavage site, leading to SpsB-independent secretion.
Transceptors as a functional link of transporters and receptors
George Diallinas
A relative newcomer in environment sensing are the so called transceptors, membrane proteins that possess both solute transport and receptor-like signaling activities. Now, the transceptor concept is further enlarged to include micronutrient sensing via the iron and zinc high-affinity transporters of Saccharomyces cerevisiae.
S. pombe placed on the prion map
Jacqueline Hayles
This article comments on work published by Sideri et al. (Microbial Cell, 2017), which identified the Ctr4 prion in S. pombe.
Using microbes as a key tool to unravel the mechanism of autophagy and the functions of the ATG proteins
Mario Mauthe1,2 and Fulvio Reggiori1,2
Microbes have served to discover and characterize unconventional functions of the ATG proteins, which are uncoupled from their role in autophagy. In our recent study, we have taken advantage of viruses as a screening tool to determine the extent of the unconventional functions of the ATG proteome and characterize one of them.
Identification of SUMO conjugation sites in the budding yeast proteome
October 2, 2017
The authors present a proteomic study that mapped SUMO acceptor lysines in budding yeast, identifying 257 potential conjugation sites, including both known and novel substrates, and providing a significant resource for future research into the functional implications of SUMOylation in yeast.
Ydj1 governs fungal morphogenesis and stress response, and facilitates mitochondrial protein import via Mas1 and Mas2
October 2, 2017
The authors descibe the role of the Hsp40 chaperone Ydj1 in Candida albicans, noting its localization to the cytosol and mitochondrial membrane, its necessity for stress responses and filamentation, and its involvement in a protein interaction network related to co-chaperones, filamentation regulators, and mitochondrial processing peptidases, with a particular focus on the impact of Ydj1 on mitochondrial morphology, function, and the import of precursor proteins.
Macrophages as drivers of an opportunistic infection
September 13, 2017
This article comments on work published by Mesureur et al. (PloS Pathog, 2017), which shows that macrophages are essential for proliferation of B. cenocepacia in the host. This suggests a new paradigm for Bcc infections and urges the development of novel anti-infectious therapies to efficiently disarm these intrinsically antibiotic resistant facultative intracellular pathogens.
Farnesol inhibits translation to limit growth and filamentation in C. albicans and S. cerevisiae
September 4, 2017
Farnesol, a quorum-sensing molecule, inhibits the switch from yeast to filamentous growth in Candida albicans by impeding translation initiation, differing from fusel alcohols that affect the initiation factor eIF2B, as it disrupts mRNA interaction with the ribosome and prevents preinitiation complex formation.
Exacerbating and reversing lysosomal storage diseases: from yeast to humans
August 25, 2017
This article summarizes the use of yeast models in advancing our understanding of lysosomal storage diseases (LSDs), where they have been instrumental in researching LSD mechanisms, screening for therapeutic compounds, and exploring genetic and gene-environment interactions relevant to diseases like Batten disease, cystinosis, and Niemann-Pick type C disease, as well as their connection to broader health issues such as viral infections and obesity.
Live fast, die fast principle in a single cell of fission yeast
August 13, 2017
This article comments on a recent study (Nakaoka and Wakamoto, PLoS Biol, 2017), which developed a microfluidics-based platform to track multiple single cell lineages until death.
The Yin & Yang of Mitochondrial Architecture – Interplay of MICOS and F1Fo-ATP synthase in cristae formation
August 6, 2017
This Editorial posits that mitochondrial cristae architecture is shaped by the interplay of MICOS and ATP synthase, with a recent study illuminating their roles in cristae formation and maintenance.
Out with the old: Hsp90 finds amino acid residue more useful than co-chaperone protein
August 1, 2017
This article comments on work published by Zuehlke et al (Nat Commun, 2017), which demonstrates that the function of one co-chaperone in yeast is replaced by posttranslational modification (PTM) of a single amino acid within Hsp90 in higher eukaryotes.
Uncovering the hidden: complexity and strategies for diagnosing latent tuberculosis
Mario Alberto Flores-Valdez
This editorial postulates that advanced proteomic and transcriptomic techniques are evolving and may enhance the detection of latent tuberculosis, thereby distinguishing true M. tuberculosis infections from other conditions, which is vital for controlling potential reactivation and transmission.