Mcintoshmckenna8878

Z Iurium Wiki

fungal pathogen Candida glabrata, Rad53 phosphorylation is not induced by DNA damage, nor do these cells arrest in S phase under these conditions, in contrast to the closely related yeast Saccharomyces cerevisiae Instead, C. glabrata cells continue to divide in the presence of DNA damage, resulting in significant cell lethality. Finally, we show that a number of genes involved in DNA repair are strongly induced by DNA damage in S. cerevisiae but repressed in C. glabrata Together, these findings shed new light on mechanisms regulating genome stability in fungal pathogens.Gram-negative bacteria produce an asymmetric outer membrane (OM) that is particularly impermeant to many antibiotics and characterized by lipopolysaccharide (LPS) exclusively at the cell surface. LPS biogenesis remains an ideal target for therapeutic intervention, as disruption could kill bacteria or increase sensitivity to existing antibiotics. While it has been known that LPS synthesis is regulated by proteolytic control of LpxC, the enzyme that catalyzes the first committed step of LPS synthesis, it remains unknown which signals direct this regulation. New details have been revealed during study of a cryptic essential inner membrane protein, YejM. Multiple functions have been proposed over the years for YejM, including a controversial hypothesis that it transports cardiolipin from the inner membrane to the OM. Strong evidence now indicates that YejM senses LPS in the periplasm and directs proteolytic regulation. Here, we discuss the standing literature of YejM and highlight exciting new insights into cell envelope maintenance.The protozoan parasite Cryptosporidium sp. is a leading cause of diarrheal disease in those with compromised or underdeveloped immune systems, particularly infants and toddlers in resource-poor localities. As an enteric pathogen, Cryptosporidium sp. invades the apical surface of intestinal epithelial cells, where it resides in close proximity to metabolites in the intestinal lumen. However, the effect of gut metabolites on susceptibility to Cryptosporidium infection remains largely unstudied. Here, we first identified which gut metabolites are prevalent in neonatal mice when they are most susceptible to Cryptosporidium parvum infection and then tested the isolated effects of these metabolites on C. parvum invasion and growth in intestinal epithelial cells. Our findings demonstrate that medium or long-chain saturated fatty acids inhibit C. parvum growth, perhaps by negatively affecting the streamlined metabolism in C. parvum, which is unable to synthesize fatty acids. Conversely, long-chain unsaturated fatty ae inhibitory effects of saturated fatty acids presented in this study may provide a framework for future studies into this enteric parasite's interactions with exogenous fatty acids during the initial stages of infection.The opportunistic human pathogen Staphylococcus aureus causes serious infectious diseases that range from superficial skin and soft tissue infections to necrotizing pneumonia and sepsis. While classically regarded as an extracellular pathogen, S. aureus is able to invade and survive within human cells. Host cell exit is associated with cell death, tissue destruction, and the spread of infection. The exact molecular mechanism employed by S. aureus to escape the host cell is still unclear. In this study, we performed a genome-wide small hairpin RNA (shRNA) screen and identified the calcium signaling pathway as being involved in intracellular infection. S. aureus induced a massive cytosolic Ca2+ increase in epithelial host cells after invasion and intracellular replication of the pathogen. This was paralleled by a decrease in endoplasmic reticulum Ca2+ concentration. Additionally, calcium ions from the extracellular space contributed to the cytosolic Ca2+ increase. As a consequence, we observed that the cytoplasvasion and cytotoxicity. The intracellular bacterium induces a cytoplasmic and mitochondrial Ca2+ overload, which results in host cell death. Thus, this study first showed how an intracellular bacterium perturbs the host cell Ca2+ homeostasis.Candida auris has emerged as a serious threat to the health care settings. Advancements in molecular biology have provided several insights into the evolution of C. auris since it was first described in 2009. However, the simultaneous emergence of four different clades of the fungus at distinct geographical locations remains a mystery. The hypotheses already proposed by researchers fall short of explaining how and why C. auris emerged. In this article, we theorize that C. YD23 auris emerged from a common ancestor, subsequently migrated to specific geographical locations, and diversified genetically. This hypothesis is supported by genomic insights, historical events, and indirect scientific facts. C. auris adapted to humans at locations and times coinciding with the divergence from the most recent common ancestor, emerging almost simultaneously as an opportunist pathogen due to antiseptic practices. Future research will support or refute this hypothesis.Influenza virus infections leave a signature of immune memory that influences future responses to infections with antigenically related strains. It has been hypothesized that the first exposure in life to H1N1 influenza virus imprints the host immune system, potentially resulting in protection from severe infection with H5N1 later in life through hemagglutinin (HA) stalk-specific antibodies. To study the specific role of the HA on protection against infection without interference of cellular immunity or humoral antineuraminidase immunity, we primed mice with influenza B viruses that express an H1 HA (group 1; B-H1), H3 HA (group 2; B-H3), or wild-type influenza B virus and subsequently challenged them at different time points with an H5N1 virus. Weight loss and survival monitoring showed that the B-H1-primed mice exhibited better protection against H5N1 compared to the control mice. Analysis of H5-specific serum IgG, before and 21 days after H5N1 challenge, evidenced the presence of anti-stalk H5 cross-reactieterosubtypic influenza strains are needed.

Autoři článku: Mcintoshmckenna8878 (Tobiasen Weiss)