Latest Articles
- Cellular Microbiology: Pathogen-Host Cell Molecular Interactions(p)ppGpp-Dependent Regulation of the Nucleotide Hydrolase PpnN Confers Complement Resistance in Salmonella enterica Serovar Typhimurium
The stringent response is an essential mechanism of metabolic reprogramming during environmental stress that is mediated by the nucleotide alarmones guanosine tetraphosphate and pentaphosphate [(p)ppGpp]. In addition to physiological adaptations, (p)ppGpp also regulates virulence programs in pathogenic bacteria, including Salmonella enterica serovar Typhimurium. S...
- CommentaryThe Neutral Vaginal pH in Mice That Is Typical of Most Mammalian Species Should Not Deter Research Using Experimental Murine Models of Candida Vaginitis
For over three decades, investigators have used estrogen-dependent rodent animal models to study pathogenesis of vulvovaginal candidiasis (VVC) or test promising antifungal drugs. One disparity not well publicized is that rodents maintain near neutral vaginal pH, which is in contrast to the acidic vaginal pH in women.
- Molecular PathogenesisThe Pyocin Regulator PrtR Regulates Virulence Expression of Pseudomonas aeruginosa by Modulation of Gac/Rsm System and c-di-GMP Signaling Pathway
In Pseudomonas aeruginosa, the second messenger cyclic-di-GMP and Gac/Rsm signaling pathways are associated with the transition from acute to chronic infection. Therefore, identification of the molecular mechanisms that govern lifestyle choice in bacteria is very important.
- Molecular PathogenesisThe Role of luxS in Histophilus somni Virulence and Biofilm Formation
S-Ribosylhomocysteinase (LuxS) is required for the synthesis of the autoinducer-2 (AI-2) quorum-sensing signaling molecule in many Gram-negative bacteria. The bovine (and ovine) opportunistic pathogen Histophilus somni contains luxS and forms a biofilm containing an exopolysaccharide (EPS) in the matrix. Since biofilm formation is regulated by quorum...
- MinireviewHeat Shock Proteins as the Druggable Targets in Leishmaniasis: Promises and Perils
Leishmania, the causative agent of leishmaniasis, is an intracellular pathogen that thrives in the insect gut and mammalian macrophages to complete its life cycle. Apart from temperature difference (26 to 37°C), it encounters several harsh conditions, including oxidative stress, inflammatory reactions, and low pH. Heat shock proteins (HSPs) play essential roles in cell survival by strategically reprogramming cellular processes...
- Host Response and Inflammation | SpotlightExogenous Reproductive Hormones nor Candida albicans Colonization Alter the Near Neutral Mouse Vaginal pH
While human vaginal pH in childbearing-age women is conclusively acidic, the mouse vaginal pH is reported as being near neutral. However, this information appears to be somewhat anecdotal with respect to vulvovaginal candidiasis, as such claims in the literature frequently lack citations of studies that specifically address this physiological factor. Given the disparate pH between mice and humans, the role of exogenous hormones and...
- Cellular Microbiology: Pathogen-Host Cell Molecular InteractionsAdoptive Transfer of Group 3-Like Innate Lymphoid Cells Restores Mouse Colon Resistance to Colonization of a Gamma Interferon-Susceptible Chlamydia muridarum Mutant
The obligate intracellular bacterium Chlamydia muridarum can colonize the mouse colon for a long period, but a gamma interferon (IFN-γ)-susceptible mutant clone fails to do so. Nevertheless, the mutant’s colonization is rescued in mice deficient in interleukin-7 receptor (IL-7R) (lacking both lymphocytes and innate lymphoid cells [ILCs]) or IFN-γ but not in mice...
- Microbial Immunity and Vaccines | SpotlightDefining the Mechanistic Correlates of Protection Conferred by Whole-Cell Vaccination against Pseudomonas aeruginosa Acute Murine Pneumonia
Pseudomonas aeruginosa is a Gram-negative pathogen that causes severe pulmonary infections associated with high morbidity and mortality in immunocompromised patients. The development of a vaccine against P. aeruginosa could help prevent infections caused by this highly antibiotic-resistant...
- Cellular Microbiology: Pathogen-Host Cell Molecular Interactions | SpotlightcAMP-Independent Activation of the Unfolded Protein Response by Cholera Toxin
Cholera toxin (CT) is an AB5 protein toxin that activates the stimulatory alpha subunit of the heterotrimeric G protein (Gsα) through ADP-ribosylation. Activation of Gsα produces a cytopathic effect by stimulating adenylate cyclase and the production of cAMP.
- Cellular Microbiology: Pathogen-Host Cell Molecular InteractionsEukaryotic SNARE VAMP3 Dynamically Interacts with Multiple Chlamydial Inclusion Membrane Proteins
Chlamydia trachomatis, an obligate intracellular pathogen, undergoes a biphasic developmental cycle within a membrane-bound vacuole called the chlamydial inclusion. To facilitate interactions with the host cell, Chlamydia modifies the inclusion membrane with type III secreted proteins, called Incs.