Microreviews, Review
Biofilm tolerance, resistance and infections increasing threat of public health
Shanshan Yang1,3, Xinfei Li1,2, Weihe Cang1,2, Delun Mu1,3, Shuaiqi Ji1,3, Yuejia An1, Rina Wu1,2,3 and Junrui Wu1,2,3
The review explores the role of biofilms in the development of bacterial resistance mechanisms and proposed therapeutic intervention strategies for biofilm related diseases.
Infinity war: Trichomonas vaginalis and interactions with host immune response
Giulia Bongiorni Galego1 and Tiana Tasca1
Trichomonas vaginalis is the pathological agent of human trichomoniasis with an incidence of 156 million cases worldwide. This review highlights parasite strategies to activate and stimulate or evade variated and complex immunological mechanisms related to the symptoms and clinical complications observed here.
Effects of the intestinal microbiota on prostate cancer treatment by androgen deprivation therapy
Safae Terrisse1, Laurence Zitvogel2-5 and Guido Kroemer6-8
Prostate cancer (PC) can be kept in check by androgen deprivation therapy (ADT, usually with the androgen synthesis inhibitor abiraterone acetate or the androgen receptor antagonist such as enzalutamide) until the tumor evolves to castration-resistant prostate cancer (CRPC). The transition of hormone-sensitive PC (HSPC) to CPRC has been explained by cancer cell-intrinsic resistance mechanisms. Recent data indicate that this transition is also marked by cancer cell-extrinsic mechanisms such as the failure of ADT-induced PC immunosurveillance, which depends on the presence of immunostimulatory bacteria in the gut. Moreover, intestinal bacteria that degrade drugs used for ADT, as well as bacteria that produce androgens, can interfere with the efficacy of ADT. Thus, specific bacteria in the gut serve as a source of testosterone, which accelerates prostate cancer progression, and men with CRPC exhibit an increased abundance of such bacteria with androgenic functions. In conclusion, the response of PC to ADT is profoundly influenced by the composition of the microbiota with its immunostimulatory, immunosuppressive and directly ADT-subversive elements.
Occurrence and potential mechanism of holin-mediated non-lytic protein translocation in bacteria
Thomas Brüser1 and Denise Mehner-Breitfeld1
Holins are generally believed to generate large membrane lesions that permit the passage of endolysins across the cytoplasmic membrane of prokaryotes, ultimately resulting in cell wall degradation and cell lysis. However, there are more and more examples known for non-lytic holin-dependent secretion of proteins by bacteria, indicating that holins somehow can transport proteins without causing large membrane lesions. Phage-derived holins can be used for a non-lytic endolysin translocation to permeabilize the cell wall for the passage of secreted proteins. In addition, clostridia, which do not possess the Tat pathway for transport of folded proteins, most likely employ non-lytic holin-mediated transport also for secretion of toxins and bacteriocins that are incompatible with the general Sec pathway. The mechanism for non-lytic holin-mediated transport is (...)
Swimming faster despite obstacles: a universal mechanism behind bacterial speed enhancement in complex fluids
Bacteria constitute about 15% of global biomass and their natural environments often contain polymers and colloids, which show complex flow properties. It is crucial to study their motion in such environments to understand their growth and spreading as well as to design synthetic microswimmers for biomedical applications. Bacterial motion in complex viscous environments, although extensively studied over the past six decades, still remains poorly understood. In our recent study combining experimental data and theoretical analysis, we found a surprising similarity between bacterial motion in dilute colloidal suspensions and polymer solutions, which challenged the established view on the role of polymer dynamics on bacterial speed enhancement. We subsequently developed a physical model that provides a universal mechanism explaining bacterial speed enhancement (...)
A roadmap for designing narrow-spectrum antibiotics targeting bacterial pathogens
Xinyun Cao1,*, Robert Landick1,2, Elizabeth A. Campbell3
This comment discusses the article "Basis of narrow-spectrum activity of fidaxomicin on Clostridioides difficile" by Cao et al. (2022, Nature).
Breaking the clip for cargo unloading from motor proteins: mechanism and significance
Keisuke Obara1, and Takumi Kamura1
The mitochondrion is an essential organelle involved in ATP generation, lipid metabolism, regulation of calcium ions, etc. Therefore, it should be inherited properly by newly generated cells. In the budding yeast Saccharomyces cerevisiae, mitochondria are passed on to daughter cells by the motor protein, Myo2, on the actin cable. The mitochondria and Myo2 are connected via the adaptor protein Mmr1. After reaching daughter cells, mitochondria are released from the actin-myosin machinery and move dynamically. In our recent paper (Obara K et al. (2022), Nat Commun, doi:10.1038/s41467-022-29704-8), we demonstrated that the regulated proteolysis of Mmr1 is required for the unloading of mitochondria from Myo2 in daughter cells. Sequential post-translational modifications of Mmr1, i.e., phosphorylation followed by ubiquitination, are essential for Mmr1 degradation and mitochondrial release from Myo2. Defects in Mmr1 degradation cause stacking and deformation of mitochondria at the bud-tip and bud-neck, where Myo2 accumulates. Compared to wild-type cells, mutant cells with defects in Mmr1 degradation possess an elevated mitochondrial membrane potential and produce higher levels of reactive oxygen species (ROS), along with hypersensitivity to oxidative stress.
Autophagy extends lifespan via vacuolar acidification
May 5, 2014
This article comments on work published by Ruckenstuhl et al. (PLoS Genet, 2014), which uses Saccharomyces cerevisiae to show that autophagy promotes lifespan extension upon MetR and requires the subsequent stimulation of vacuolar acidification, while it is epistatic to the equally autophagy-dependent anti-aging pathway triggered by TOR1 inhibition or deletion.
When less is more: hormesis against stress and disease
May 5, 2014
This article condenses the conceptual and potentially therapeutic importance of hormesis by providing a short overview of current evidence in favor of the cytoprotective impact of hormesis, as well as of its underlying molecular mechanisms.
Morphed and moving: TNFα-driven motility promotes cell dissemination through MAP4K4-induced cytoskeleton remodeling
April 24, 2014
This article comments on work published by Ma and Baumgartner (PLoS Patho, 2014), which investigated Theileria parasite control of host cell motile properties in the context of inflammatory signaling.
Hormesis: a fundamental concept in biology
April 23, 2014
This article addresses the concept of hormetic dose response, which describes the limits to which integrative endpoints can be modulated (i.e., enhanced or diminished) by pharmaceutical, chemical and physical means.
Live longer on MARS: a yeast paradigm of mitochondrial adaptive ROS signaling in aging
April 23, 2014
In this article, the potential relevance of Mitochondrial Adaptive ROS Signaling (MARS) to the human disease Ataxia-Telangiectasia and as a potential anti-aging target is discussed.
Prokaryotic Argonautes – variations on the RNA interference theme
April 15, 2014
This article comments on work published by Swarts et al. (Nature, 2014), which demonstrates that Argonaute family protein of the bacterium Thermus thermophilus acts as a barrier for the uptake and propagation of foreign DNA.
Longevity pathways and maintenance of the proteome: the role of autophagy and mitophagy during yeast ageing
April 7, 2014
This review describes recent findings that shed light on how longevity pathways and metabolic status impact maintenance of the proteome in both yeast ageing paradigms. These findings demonstrate that yeast remain a powerful model system for elucidating these relationships and their influence on ageing regulation.
Secondary structures involving the poly(A) tail and other 3’ sequences are major determinants of mRNA isoform stability in yeast
April 5, 2014
This article comments on work published by Geisberg et al. (Cell (2014), which points to an important role for mRNA structure at 3’ termini in governing transcript stability, likely by reducing the interaction of the mRNA with the degradation apparatus.
De novo peroxisome biogenesis revisited
April 1, 2014
This article comments on work published by Knoops et al. (JCB, 2014), which describes an alternative peroxisome formation pathway in yeast pex3 and pex19 cells, which relies on the existence of small peroxisomal remnants that are present in these cells.
Transcriptional and genomic mayhem due to aging-induced nucleosome loss in budding yeast
April 1, 2014
This article comments on work published by Zheng et al. (Genes and Development, 2014), which investigated a loss of histones during replicative aging in budding yeast, which was also accompanied by a significantly-increased frequency of genomic instability including DNA breaks, chromosomal translocations, retrotransposition, and transfer of mitochondrial DNA into the nuclear genome.