The nasal mucosa is a crucial filtering organ to prevent attachment and invasion of pathogens. To assess nasal health in relation to lung health, transverse cross sections of the nasal turbinates of 121 pigs suffering from respiratory disease and sent for diagnostic necropsy were scored visually and by an artificial intelligence (AI) medical diagnostic application (AI DIAGNOS), resulting in a high correlation of both scores ( < 0.001).
View Article and Find Full Text PDFThe decision to euthanize a compromised pig can be challenging for pig farmers and veterinarians. To understand more about the challenges in Germany, a cross-sectional online survey was conducted. Based on a hybrid design, the responses of 39 veterinarians and 62 pig farmers were analyzed to generate a list of common clinical signs associated with the euthanasia of sows, fatteners, and piglets.
View Article and Find Full Text PDFTimely euthanasia of a compromised pig in farming practice has been identified as a critical topic in veterinary medicine. The questions 'why and when are pigs euthanized' and 'what influences the decision making process' need to be answered to improve the situation. In the past five years, work addressing these issues has been published in the literature, however, a synthesis of the findings is missing.
View Article and Find Full Text PDFToxin-antitoxin (TA) modules are prevalent in prokaryotic genomes, often in substantial numbers. For instance, the genome alone harbors close to 100 TA modules, half of which belong to a singular type. Traditionally ascribed multiple biological roles, recent insights challenge these notions and instead indicate a predominant function in phage defense.
View Article and Find Full Text PDFMany bacteria encode multiple toxin-antitoxin (TA) systems targeting separate, but closely related, cellular functions. The toxin of the system, HipA, is a kinase that inhibits translation via phosphorylation of glutamyl-tRNA synthetase. Enteropathogenic O127:H6 encodes the -like, tripartite TA system; , in which the HipT toxin specifically targets the tryptophanyl-tRNA synthetase, TrpS.
View Article and Find Full Text PDFAllylic alcohols are a privileged motif in natural product synthesis and new methods that access them in a stereoselective fashion are highly sought after. Toward this goal, we found that chiral acetonide-protected polyketide fragments performing the Hoppe-Matteson-Aggarwal rearrangement in the absence of sparteine with high yields and diastereoselectivities rendering this protocol a highly valuable alternative to the Nozaki-Hiyama-Takai-Kishi reaction. Various stereodyads and -triads were investigated to determine their substrate induction.
View Article and Find Full Text PDFLead vocals constitute the central element of popular music. Here, the lead-vocal-to-accompaniment level ratio (LAR) was estimated from representative recordings of popular music. Measuring the LAR from 1946 to 2020, two distinct phases were observed: the average LAR decreased from around 5 dB to 1 dB until around 1975 but remained static from thereon.
View Article and Find Full Text PDFDuring antibiotic persistence, bacterial cells become transiently tolerant to antibiotics by restraining their growth and metabolic activity. Detailed molecular characterization of antibiotic persistence is hindered by low count of persisting cells and the need for their isolation. Here, we used sustained addition of stable isotope-labeled lysine to selectively label the proteome during -induced persistence and -induced resuscitation of Escherichia coli cells in minimal medium after antibiotic treatment.
View Article and Find Full Text PDFA new species of eelpout genus Pachycara Zugmayer, 1911 is described based on five specimens caught at a depth of 24193275 m along the Central and Southeast Indian Ridges in the Indian Ocean. The specimens were collected during the INDEX cruises in 2016, 2018 and 2019, respectively. The new species is distinguished from its congeners by the following combination of characters: scales and pelvic fins absent; lateral line configuration mediolateral; dorsal fin origin associated with vertebrae 79 with no free predorsal pterygiophores; vertebrae 2728 + 5759 = 8587; dorsal-fin rays 7880, anal-fin rays 5862; pectoral fin rays 1315.
View Article and Find Full Text PDFToxin-antitoxin modules function in the genetic stability of mobile genetic elements, bacteriophage defense, and antibiotic tolerance. A gain-of-function mutation of the Escherichia coli K-12 module can induce antibiotic tolerance in a subpopulation of bacterial cells, a phenomenon known as persistence. HipA is a Ser/Thr kinase that phosphorylates and inactivates glutamyl tRNA synthetase, inhibiting cellular translation and inducing the stringent response.
View Article and Find Full Text PDFRibosome hibernation is a universal translation stress response found in bacteria as well as plant plastids. The term was coined almost two decades ago and despite recent insights including detailed cryo-EM structures, the physiological role and underlying molecular mechanism of ribosome hibernation has remained unclear. Here, we demonstrate that Escherichia coli hibernation factors RMF, HPF and RaiA (HFs) concurrently confer ribosome hibernation.
View Article and Find Full Text PDFAntibiotic-tolerant persisters are often implicated in treatment failure of chronic and relapsing bacterial infections, but the underlying molecular mechanisms have remained elusive. Controversies revolve around the relative contribution of specific genetic switches called toxin-antitoxin (TA) modules and global modulation of cellular core functions such as slow growth. Previous studies on uropathogenic Escherichia coli observed impaired persister formation for mutants lacking the pasTI locus that had been proposed to encode a TA module.
View Article and Find Full Text PDFThe Klebsiella pneumoniae species complex includes important opportunistic pathogens which have become public health priorities linked to major hospital outbreaks and the recent emergence of multidrug-resistant hypervirulent strains. Bacterial virulence and the spread of multidrug resistance have previously been linked to toxin-antitoxin (TA) systems. TA systems encode a toxin that disrupts essential cellular processes, and a cognate antitoxin which counteracts this activity.
View Article and Find Full Text PDFAdditive implantation of electrocatalysts onto the internal surface of porous cathodes holds great promise to accelerate the electrochemical reactions within solid oxide fuel cells (SOFCs). Here we utilize atomic layer deposition (ALD) to apply dual catalysts with (MnCo)O and a minute amount of Pt on the cathode consisting of lanthanum strontium manganite (LSM) and yttria-stabilized zirconia (YSZ). Coating this material with optimum ALD layer thickness resulted in a 53% reduction of polarization resistance and a 350% SOFC peak power density enhancement at 750 °C.
View Article and Find Full Text PDFHorizontal gene transfer through natural competence is an important driving force of bacterial evolution and antibiotic resistance development. In several Gram-negative pathogens natural competence is regulated by the concerted action of cAMP receptor protein (CRP) and the transcriptional co-regulator Sxy through a subset of CRP-binding sites (CRP-S sites) at genes encoding competence factors. Despite the wealth of knowledge on CRP's structure and function it is not known how CRP and Sxy act together to activate transcription.
View Article and Find Full Text PDFThe E. coli hicAB type II toxin-antitoxin locus is unusual by being controlled by two promoters and by having the toxin encoded upstream of the antitoxin. HicA toxins contain a double-stranded RNA-binding fold and cleaves both mRNA and tmRNA in vivo, while HicB antitoxins contain a partial RNase H fold and either a helix-turn-helix (HTH) or ribbon-helix-helix domain.
View Article and Find Full Text PDFActive hydrothermal vents are small-scale habitats hosting endemic fauna in a well-defined zonation around fluid effluents. The fauna of inactive hydrothermal vents and its relation to active vents and non-vent area is poorly known. Characterizing inactive areas is prerequisite to establish protected areas, especially in the context of potential seafloor massive sulfide mining, which targets inactive sites.
View Article and Find Full Text PDFBacteria undergoing nutrient starvation induce the ubiquitous stringent response, resulting in gross physiological changes that reprograms cell metabolism from fast to slow growth. The stringent response is mediated by the secondary messengers pppGpp and ppGpp collectively referred to as (p)ppGpp or 'alarmone'. In Escherichia coli, two paralogs, RelA and SpoT, synthesize (p)ppGpp.
View Article and Find Full Text PDFBacterial toxin-antitoxin pairs play important roles in bacterial multidrug tolerance. Gcn5-related N-acetyltransferase (GNAT) toxins inhibit translation by acetylation of aminoacyl-tRNAs and are counteracted by direct contacts with cognate ribbon-helix-helix (RHH) antitoxins. Our previous analysis showed that the GNAT toxin KacT and RHH antitoxin KacA of Klebsiella pneumoniae form a heterohexamer in solution and that the complex interacts with the cognate promoter DNA, resulting in negative autoregulation of kacAT transcription.
View Article and Find Full Text PDFType II toxin-antitoxin (TA) modules encode a stable toxin that inhibits cell growth and an unstable protein antitoxin that neutralizes the toxin by direct protein-protein contact. of strain K-12 codes for HipA, a serine-threonine kinase that phosphorylates and inhibits glutamyl-tRNA synthetase. Induction of inhibits charging of glutamyl-tRNA that, in turn, inhibits translation and induces RelA-dependent (p)ppGpp synthesis and multidrug tolerance.
View Article and Find Full Text PDFThe stringent response alarmones pppGpp and ppGpp are essential for rapid adaption of bacterial physiology to changes in the environment. In Escherichia coli, the nucleosidase PpnN (YgdH) regulates purine homeostasis by cleaving nucleoside monophosphates and specifically binds (p)ppGpp. Here, we show that (p)ppGpp stimulates the catalytic activity of PpnN both in vitro and in vivo causing accumulation of several types of nucleobases during stress.
View Article and Find Full Text PDFRegulatory RNAs and RNA-binding proteins (RBPs) play critical roles in virulence gene expression in pathogenic bacteria. A wealth of regulatory RNAs have been identified in bacterial pathogens using RNA-seq and recent technical advances are uncovering their mRNA targets. UV-crosslinking is a powerful tool for identifying protein binding sites throughout the transcriptome providing base-pair resolution of sites in vivo.
View Article and Find Full Text PDFProtein synthesis consumes a large fraction of available resources in the cell. When bacteria encounter unfavorable conditions and cease to grow, specialized mechanisms are in place to ensure the overall reduction of costly protein synthesis while maintaining a basal level of translation. A number of ribosome-associated factors are involved in this regulation; some confer an inactive, hibernating state of the ribosome in the form of 70S monomers (RaiA; this and the following are based on Escherichia coli nomenclature) or 100S dimers (RMF and HPF homologs), and others inhibit translation at different stages in the translation cycle (RsfS, YqjD and paralogs, SRA, and EttA).
View Article and Find Full Text PDF