Read by QxMD icon Read

Journal of Bacteriology

Milton H Saier
The universal triple nucleotide genetic code is often viewed as a given, randomly selected through evolution. However, as summarized in this article, many observations and deductions within structural and thermodynamic frameworks help to explain the forces that must have shaped the code during the early evolution of life on Earth. Importance In this minireview, many revealing aspects of the "universal" genetic code are described and discussed. These characteristics, taken together, can be rationalized in a thermodynamic context with conceptualization of its overall construction...
April 22, 2019: Journal of Bacteriology
Emily A Williams McMackin, Louise Djapgne, Jodi M Corley, Timothy L Yahr
Type III secretion systems (T3SS) are widely distributed in Gram-negative microorganisms and critical for host-pathogen and host-symbiont interactions with plants and animals. Central features of the T3SS are a highly conserved set of secretion and translocation genes and contact-dependence wherein host-pathogen interactions trigger effector protein delivery and serve as an inducing signal for T3SS gene expression. In addition to these conserved features there are also pathogen-specific properties that include a unique repertoire of effector genes and mechanisms to control T3SS gene expression...
April 22, 2019: Journal of Bacteriology
Erin K Cassin, Boo Shan Tseng
The ability of Pseudomonas aeruginosa to form biofilms, which are communities of cells encased in a self-produced extracellular matrix, protects the cells from antibiotics and the host immune response. While some biofilm matrix components, such as exopolysaccharides and extracellular DNA, are relatively well characterized, the extracellular matrix proteins remain understudied. Multiple proteomic analyses of the P. aeruginosa soluble biofilm matrix and outer membrane vesicles, which are a component of the matrix, have identified OprF as an abundant matrix protein...
April 22, 2019: Journal of Bacteriology
Shiwei Zhu, Maren Schniederberend, Daniel Zhitnitsky, Ruchi Jain, Jorge E Galán, Barbara I Kazmierczak, Jun Liu
The bacterial flagellum is a sophisticated self-assembling nanomachine responsible for motility in many bacterial pathogens including Pseudomonas aeruginosa, Vibrio spp., and Salmonella enterica The bacteria flagellum has been studied extensively in the model systems Escherichia coli and Salmonella Typhimurium, yet the range of variation in flagellar structure and assembly remains incompletely understood. Here we used cryo-electron tomography and subtomogram averaging to determine in situ structures of polar flagella in P...
April 22, 2019: Journal of Bacteriology
Aretha Fiebig
In aquatic environments, Caulobacter spp. are often present at the boundary between liquid and air known as the neuston. I report an approach to study temporal features of Caulobacter crescentus colonization and pellicle biofilm development at the air-liquid interface, and have defined the role of cell surface structures in this process. At this interface, C. crescentus initially forms a monolayer of cells bearing a surface adhesin known as the holdfast. When excised from the liquid surface, this monolayer strongly adheres to glass...
April 22, 2019: Journal of Bacteriology
Chao He, Ning Liu, Fudong Li, Xiaoyu Jia, Hui Peng, Yanhong Liu, Yazhong Xiao
A bacterial inverting glycosyltransferase EarP transfers rhamnose from dTDP-β-L-rhamnose (TDP-Rha) to Arg32 of translation elongation factor P (EF-P) to activate its function. Here we report structural and biochemical characterization of Pseudomonas aeruginosa EarP. In contrast to recently reported Neisseria meningitidis EarP, P. aeruginosa EarP exhibits differential conformational changes upon TDP-Rha and EF-P binding. Sugar donor binding enhances acceptor binding to EarP as revealed by structural comparison between the apo, TDP-Rha- and TDP/EF-P bound forms and isothermal titration calorimetry experiments...
April 22, 2019: Journal of Bacteriology
Lauren L Prister, Jing Xu, H Steven Seifert
The major subunit of the Type IV pilus (T4p) of Neisseria gonorrhoeae undergoes Antigenic variation (Av) dependent on a guanine quadruplex (G4) DNA structure located upstream of the pilin gene. Since the presence of G4 DNA induces genome instability in both eukaryotic and prokaryotic chromosomes, we tested whether a double strand break (DSB) at the site of the pilE G4 sequence can substitute for G4 directed pilin Av. The G4 motif was replaced by an I-SceI cut site and the cut site was also introduced to locations near the origin of replication and the terminus...
April 15, 2019: Journal of Bacteriology
Krista M Armbruster, Gloria Komazin, Timothy C Meredith
Bacterial lipoproteins are globular proteins anchored to the extracytoplasmic surfaces of cell membranes through lipidation at a conserved N -terminal cysteine. Lipoproteins contribute to an array of important cellular functions for bacteria, as well as being a focal point for innate immune system recognition through binding to Toll-like receptor 2 (TLR2) heterodimer complexes. Although lipoproteins are conserved among nearly all classes of bacteria, the presence and type of α-amino-linked acyl chain is highly variable and even strain specific within a given bacterial species...
April 15, 2019: Journal of Bacteriology
Stéphane Pinhal, Delphine Ropers, Johannes Geiselmann, Hidde de Jong
During aerobic growth on glucose, Escherichia coli excretes acetate, a mechanism called "overflow metabolism". At high concentrations, the secreted acetate inhibits growth. Several mechanisms have been proposed for explaining this phenomenon, but a thorough analysis is hampered by the diversity of experimental conditions and strains used in these studies. Here, we describe the construction of a set of isogenic strains that remove different parts of the metabolic network involved in acetate metabolism...
April 15, 2019: Journal of Bacteriology
Douglas A Higgins, John Gladden, Jeff Kimbrel, Blake A Simmons, Steven W Singer, Michael P Thelen
Plant cell walls contain a renewable, nearly limitless supply of sugar that could be used to support microbial production of commodity chemicals and biofuels. Imidazolium ionic liquid (IIL) solvents are among the best reagents for gaining access to the sugars in this otherwise recalcitrant biomass. However, the sugars from IIL-treated biomass are inevitably contaminated with residual IILs that inhibit growth in bacteria and yeast, blocking biochemical production by these organisms. IIL toxicity is, therefore, a critical roadblock in many industrial biosynthetic pathways...
April 15, 2019: Journal of Bacteriology
Kathryn E Cherny, Karin Sauer
The dispersion of biofilms is an active process resulting in the release of planktonic cells from the biofilm structure. While much is known about the process of dispersion cue perception and the subsequent modulation of the c-di-GMP pool, little is known about subsequent events resulting in the release of cells from the biofilm. Given that dispersion coincides with void formation and an overall erosion of the biofilm structure, we asked whether dispersion involves degradation of the biofilm matrix. Here, we focused on eDNA due to its almost universal presence in the matrix of biofilm-forming species...
April 15, 2019: Journal of Bacteriology
Timothy L Yahr, Craig D Ellermeier
The 25th Annual Midwest Microbial Pathogenesis Conference (MMPC) was held at the University of Iowa from September 28-30, 2018. The conference has a long-standing tradition of providing scientists from the Midwest with a forum to present and discuss cutting edge advances in microbial pathogenesis with particular focus on bacterial interactions with the environment, host, and other microbes. This commentary summarizes the genesis of the MMPC, topics presented at the conference, and manuscripts found in the special MMPC section of this Journal of Bacteriology issue...
April 15, 2019: Journal of Bacteriology
Libera Latino, Delphine Patin, Dimitri Chérier, Thierry Touzé, Christine Pourcel, Hélène Barreteau, Dominique Mengin-Lecreulx
Certain Pseudomonas aeruginosa strains produce a homolog of colicin M, named PaeM, that specifically inhibits peptidoglycan biosynthesis of susceptible P. aeruginosa strains by hydrolyzing the lipid II intermediate precursor. Two variants of this pyocin were identified whose sequences mainly differed in the N-terminal protein moiety, i.e. the region involved in the binding to the FiuA outer membrane receptor and translocation into the periplasm. The antibacterial activity of these two variants, PaeM1 and PaeM2, was tested against various P...
April 15, 2019: Journal of Bacteriology
Malcolm E Winkler, Donald A Morrison
DNA uptake by natural competence is a central process underlying the genetic plasticity, biology, and virulence of the human respiratory opportunistic pathogen, Streptococcus pneumoniae. A study in this issue (Slager et al , J Bacteriol doi: 10.1128/JB.00780-18) combines deep-genome annotation and high-resolution transcriptome analyses to considerably extend the previous model of temporal regulation of competence at the operon and component-gene levels. This extended study also provides a playbook for updating, refining, and extending genomic data sets and making them publicly available...
April 15, 2019: Journal of Bacteriology
Ritesh Rajesh Sevalkar, Divya Arora, Prabhat Ranjan Singh, Ranjeet Singh, Vinay K Nandicoori, Subramanian Karthikeyan, Dibyendu Sarkar
A hallmark feature of Mycobacterium tuberculosis (Mtb) pathogenesis lies in the ability of the pathogen to survive within the macrophages under a stressful environment. Thus, coordinated regulation of stress proteins is critically important for an effective adaptive response of Mtb, failure to which results in elevated immune recognition of the tubercle bacilli with reduced survival during chronic infections. Here, we show that virulence regulator PhoP impacts on global regulation of heat-shock proteins, which protect Mtb against stress generated by macrophages during infection...
April 8, 2019: Journal of Bacteriology
Phuong M Tran, Michael Feiss, Kyle J Kinney, Wilmara Salgado-Pabón
Phage regulatory switches (phage-RSs) are a newly described form of active lysogeny where prophages function as regulatory mechanisms for expression of chromosomally-encoded, bacterial genes. In Staphylococcus aureus, φSa3int is a widely-distributed family of prophages that integrate into the β-toxin structural gene hlb effectively inactivating it. However, β-toxin producing strains often arise during infections and are more virulent in experimental infective endocarditis and pneumonia infections. We present evidence that in S...
April 8, 2019: Journal of Bacteriology
Ute Lindenstrauß, Constanze Pinske
Trabulsiella guamensis is a non-pathogenic enterobacterium that was isolated from a vacuum cleaner on the island of Guam. It has one H2 -oxidizing Hyd-2-type hydrogenase (Hyd), and encodes a H2 -evolving Hyd that is most similar to the uncharacterized Escherichia coli formate hydrogenlyase (FHL-2 Ec ) complex. The FHL-2 Tg complex is predicted to have 5 membrane-integral and between 4-5 cytoplasmic subunits. We could show that FHL-2 Tg complex catalyses the disproportionation of formate to CO2 and H2 FHL-2 Tg has an activity similar to the E...
April 8, 2019: Journal of Bacteriology
Cassandra E Nelson, Weiliang Huang, Luke K Brewer, Angela T Nguyen, Maureen A Kane, Angela Wilks, Amanda G Oglesby-Sherrouse
Iron is a critical nutrient for most microbial pathogens, and the immune system exploits this requirement by sequestering iron. The opportunistic pathogen Pseudomonas aeruginosa exhibits a high requirement for iron yet an exquisite ability to overcome iron deprivation during infection. Upon iron starvation, P. aeruginosa induces the expression of several high affinity iron acquisition systems, as well as the PrrF sRNAs that mediate an iron-sparing response. Here, we used liquid chromatography-tandem mass spectrometry to conduct proteomics of P...
April 8, 2019: Journal of Bacteriology
Daniel F Rojas-Tapias, John D Helmann
In B. subtilis , the Spx transcription factor controls a large regulon in response to disulfide, heat, and cell wall stresses. The regulatory mechanisms that activate the Spx regulon are remarkably complex, and involve changes in transcription, proteolysis, and post-translational modifications. To identify genes involved in Spx regulation, we performed a transposon screen for mutations affecting expression of trxB , a Spx-dependent gene. Inactivation of ctsR , encoding the regulator of the Clp proteases, reduced trxB expression and lowered Spx levels...
April 8, 2019: Journal of Bacteriology
Daniel B Kearns
The bacterial secondary metabolite cyclic-di-GMP is a widespread, cytoplasmic signal that promotes a physiological transition in which motility is inhibited and biofilm formation is activated.….
April 8, 2019: Journal of Bacteriology
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"