Review, Reviews
Histone deacetylases: revealing the molecular base of dimorphism in pathogenic fungi
Alberto Elías-Villalobos1,2, Dominique Helmlinger2 and José I. Ibeas1
Fungi, as every living organism, interact with the external world and have to adapt to its fluctuations. For pathogenic fungi, such interaction involves adapting to the hostile environment of their host. Survival depends on the capacity of fungi to detect and respond to external stimuli, which is achieved through a tight and efficient genetic control. Elías-Villalobos et al. propose that histone acetylation is critical to the proper timing and induction of transcription of the genes encoding factors that coordinate changes in morphology with pathogenesis.
Electron microscopy for ultrastructural analysis and protein localization in Saccharomyces cerevisiae
Andri Frankl, Muriel Mari and Fulvio Reggiori
The yeast Saccharomyces cerevisiae is a key model system for studying of a multitude of cellular processes because of its amenability to genetics, molecular biology and biochemical procedures. The goal of this review is to guide researchers that want to investigate a particular process at the ultrastructural level in yeast by aiding in the selection of the most appropriate approach to visualize a specific structure or subcellular compartment.
Complex regulation of the sirtuin-dependent reversible lysine acetylation system of Salmonella enterica
Kristy L. Hentchel1,2 and Jorge C. Escalante-Semerena1
The extensive involvement of the reversible lysine acylation (RLA) system in metabolism has attracted the attention of investigators interested in understanding the fundamentals of prokaryotic and eukaryotic cell function. Here the authors discuss the implications of recently reported work performed in the enteropathogen Salmonella enterica (mBio (2015) 6(4):e00891-15), which provided the first insights into the integration of the transcriptional regulation of genes encoding the RLA system with the acs gene encoding the central metabolic enzyme acetyl-CoA synthetase (Acs).
A bacterial volatile signal for biofilm formation
Yun Chen2, Kevin Gozzi1, and Yunrong Chai1
Bacteria constantly monitor the environment they reside in and respond to potential changes in the environment through a variety of signal sensing and transduction mechanisms in a timely fashion. In their recent study (Chen, et al. mBio (2015), 6: e00392-15), the authors demonstrated that the soil bacterium Bacillus subtilis uses acetic acid as a volatile signal to coordinate the timing of biofilm formation within physically separated cells in the community. They also showed that the bacterium possesses an intertwined gene network to produce, secrete, sense, and respond to acetic acid, in stimulating biofilm formation.
The great escape: Pseudomonas breaks out of the lung
Angelica Zhang1, Stephanie M. Rangel1, and Alan R. Hauser1,2
The Gram-negative bacterium Pseudomonas aeruginosa is a major cause of hospital-acquired infections and the focus of much attention due to its resistance to many conventional antibiotics. This article discusses the potential mechanisms by which these processes occur as well as the novel techniques used to study ExoS function in vivo.
Peering into the ‘black box’ of pathogen recognition by cellular autophagy systems
Shu-chin Lai# and Rodney J Devenish
Autophagy is an intracellular process that plays an important role in protecting eukaryotic cells and maintaining intracellular homeostasis. This review summarises the available evidence regarding the specific recognition of invading pathogens by which they are targeted into host autophagy pathways.
Per aspera ad astra: When harmful chromosomal translocations become a plus value in genetic evolution. Lessons from Saccharomyces cerevisiae
Valentina Tosato and Carlo V. Bruschi
This review will focus on chromosomal translocations (either spontaneous or induced) in budding yeast. Indeed, very few organisms tolerate so well aneuploidy like Saccharomyces, allowing in depth studies on chromosomal numerical aberrations. The phenomenon of post-translocational adaptation (PTA) is discussed, providing some new unpublished data and proposing the hypothesis that translocations may drive evolution through adaptive genetic selection.
Intracellular phase for an extracellular bacterial pathogen: MgtC shows the way
Audrey Bernut1,#, Claudine Belon1, Chantal Soscia2, Sophie Bleves2, Anne-Béatrice Blanc-Potard1
This article discusses the article "A macrophage subversion factor is shared by intracellular and extracellular pathogens" by Belon et al. (PLoS Pathogens 11(6): e1004969, 2015).
The role of transcriptional ‘futile cycles’ in autophagy and microbial pathogenesis
Guowu Hu1, Travis McQuiston1, Amélie Bernard2, Yoon-Dong Park1, Jin Qiu1, Ali Vural3, Nannan Zhang1, Scott R. Waterman1, Nathan H. Blewett4, Timothy G. Myers5, John H. Kehrl3, Gulbu Uzel1, Daniel J. Klionsky2 and Peter R. Williamson1
Eukaryotic cells utilize macroautophagy (hereafter autophagy) to recycle cellular materials during nutrient stress. Target of rapamycin (Tor) is a central regulator of this process, acting by post-translational mechanisms, phosphorylating preformed autophagy-related (Atg) proteins to repress autophagy during log-phase growth. A role for this regulatory process in fungal virulence was further demonstrated by showing that overexpression of the Dcp2-associated mRNA-binding protein Vad1 in the AIDS-associated pathogen Cryptococcus neoformans results in constitutive repression of autophagy even under starvation conditions as well as attenuated virulence in a mouse model. In summary, Tor-dependent post-transcriptional regulation of autophagy plays a key role in the facilitation of microbial pathogenesis.
Adaptive bacterial response to low level chlorhexidine exposure and its implications for hand hygiene
March 7, 2019
This article shows that bacteria can adapt to low levels of Chlorhexidine digluconate (CHG), resulting in increased tolerance and cross-resistance to other antimicrobials, suggesting caution in the widespread use of CHG to minimize avoidable selection pressure for resistance.
Microevolution of the pathogenic yeasts Candida albicans and Candida glabrata during antifungal therapy and host infection
February 8, 2019
This review explores how Candida albicans and Candida glabrata, common fungal pathogens resistant to antifungal therapy, adapt and evolve within different environments, aiming to identify stable adaptive mechanisms as potential drug targets.
The extracellular matrix of mycobacterial biofilms: could we shorten the treatment of mycobacterial infections?
January 18, 2019
The article discusses the challenges presented by biofilms formed by non-tuberculous mycobacteria (NTM) species, which can lead to persistent infections that are difficult to treat due to phenotypic drug tolerance. The role of various cell wall components in mycobacterial biofilm formation is outlined, with a particular focus on Mycobacterium tuberculosis.
Guidelines for DNA recombination and repair studies: Cellular assays of DNA repair pathways
January 7, 2019
DNA recombination, repair and mutagenesis assays are powerful tools but each comes with its particular advantages and limitations. Here the most commonly used assays are reviewed, discussed, and presented as the guidelines for future studies.
Guidelines for DNA recombination and repair studies: Mechanistic assays of DNA repair processes
January 7, 2019
Mechanistic assays of DNA repair processes are a powerful tools but each comes with its particular advantages and limitations. Here the most commonly used assays are reviewed, discussed, and presented as the guidelines for future studies.
Pathways of host cell exit by intracellular pathogens
October 18, 2018
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.
Protective roles of ginseng against bacterial infection
September 19, 2018
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
September 18, 2018
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
August 28, 2018
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.