Bacterial pathogens

Sun, 09/20/2020 - 06:15
Author(s): Karine Patrin Pontin, Karen Apellanis Borges, Thales Quedi Furian, Daiane Carvalho, Daiane Elisa Wilsmann, Henrique Ribeiro Piaggio Cardoso, Annelise Kopp Alves, Gabriela Zottis Chitolina, Carlos Tadeu Pippi Salle, Hamilton Luiz de Souza Moraes, Vladimir Pinheiro do Nascimento
Sun, 09/20/2020 - 00:00
Antibiotic treatments initiated on Emergency Departments (ED) are empirical. Therefore, knowledge of local susceptibility patterns is important. Despite this, data on expected pathogens and their resistance profile are scarce from EDs internationally. The study aim was to assess the epidemiology and resistance patterns of bacterial isolates from a tertiary-care ED over 5 years, focusing on ESKAPE...
Sat, 09/19/2020 - 10:03
Typhoid toxin is a virulence factor of Salmonella enterica serovar Typhi, the causative agent of typhoid fever, and is thought to be responsible for the symptoms of severe disease. This toxin has a unique A2B5 architecture with two active subunits, the ADP ribosyl transferase PltA and the DNase CdtB, linked to a pentameric B subunit, which is alternatively made of PltB or PltC. Here, we describe...
Sat, 09/19/2020 - 10:03
Stealthy intracellular bacterial pathogens are known to establish persistent and sometimes lifelong infections. Some of these pathogens also have a tropism for the reproductive system, thereby increasing the risk of reproductive disease and infertility. To date, the pathogenic mechanism involved remains poorly understood. Here, we demonstrate that Brucella abortus, a notorious reproductive...
Sat, 09/19/2020 - 10:03
Successful colonization by enteric pathogens is contingent upon effective interactions with the host and the resident microbiota. These pathogens thus respond to and integrate myriad signals to control virulence. Long-chain fatty acids repress the virulence of the important enteric pathogens Salmonella enterica and Vibrio cholerae by repressing AraC-type transcriptional regulators in...
Sat, 09/19/2020 - 10:03
Reproductive failure is the hallmark of brucellosis in animals. An uncommon but important complication in pregnant women who become acutely infected with Brucella melitensis is spontaneous pregnancy loss or vertical transmission to the fetus. Unfortunately, the mechanism behind reproductive failure is still obscure, partially due to the lack of a proper study model. Recently, it was demonstrated...
Sat, 09/19/2020 - 00:00
The reassessment of known but neglected natural compounds is a vital strategy for providing novel lead structures urgently needed to overcome antimicrobial resistance. Scaffolds with resistance-breaking properties represent the most promising candidates for a successful translation into future therapeutics. Our study focuses on chelocardin, a member of the atypical tetracyclines, and its...
Fri, 09/18/2020 - 16:00
A screen of a eukaryotic kinase inhibitor library in an established intracellular infection model identified a set of drug candidates enabling intracellular killing of Mycobacterium tuberculosis (M.tb). Screen validity was confirmed internally by a Z′ = 0.5 and externally by detecting previously reported host-targeting anti-M.tb compounds. Inhibitors of the CHK kinase family, specifically...
Fri, 09/18/2020 - 16:00
The study evaluated the in vitro antimicrobial and antibiofilm efficacy of an antimicrobial peptide (AMP), lactoferricin (17–30) [Lfcin (17–30)], against biofilm-forming multi-drug-resistant (MDR) strains of enteroaggregative Escherichia coli (EAEC), and subsequently, the in vivo antimicrobial efficacy was assessed in a Galleria mellonella larval model. Initially, minimum inhibitory concentration...
Fri, 09/18/2020 - 16:00
Coxiella burnetii is the agent that causes acute and chronic Q fever infections in humans. Although the isolates studied so far have shown that the two forms of the disease differ in virulence potential thus, implying a variance in their proteomic profile, the methods used do not deliver enough discriminatory capability and often, human infections may be mis-diagnosed. The current study adds...
Fri, 09/18/2020 - 10:02
Salmonella enterica serovar Hvittingfoss is an important foodborne serotype of Salmonella, being detected in many countries where surveillance is conducted. Outbreaks can occur, and there was a recent multistate foodborne outbreak in Australia. S. Hvittingfoss can be found in animal populations, though a definitive animal host has not been established. Six species of birds were sampled at Roebuck...
Fri, 09/18/2020 - 10:02
Periprosthetic joint infection (PJI) occurring after artificial joint replacement is a major clinical issue requiring multiple surgeries and antibiotic interventions. Staphylococcus aureus is the bacterium most commonly responsible for PJI. Recent in vitro research has shown that staphylococcal strains rapidly form aggregates in the presence of synovial fluid (SF). We hypothesize that these...
Fri, 09/18/2020 - 08:02
by Elisa Peh, Sophie Kittler, Felix Reich, Corinna Kehrenberg Contaminated poultry meat is considered to be the main source of human infection with Campylobacter spp., a pathogen that asymptomatically colonizes broiler chickens during fattening and contaminates carcasses during slaughter. To prevent or reduce the colonization of broiler flocks with Campylobacter spp., applying different organic...
Fri, 09/18/2020 - 06:15
Author(s): Heather Craven, Catherine McAuley, Murray Hannah, Lesley Duffy, Narelle Fegan, Stephen Forsythe The emergence of Cronobacter as an important potential pathogen for new born children and its occurrence in powdered infant formulae has generated a need to develop new management practices for this food group. This includes reduction of the prevalence of Cronobacter in manufacturing...
Fri, 09/18/2020 - 06:12
LWT
Author(s): Chenghui Zhang, Changzhu Li, Mohamed A. Abdel-Samie, Haiying Cui, Lin Lin Listeria monocytogenes (L. monocytogenes) can adhere to biological or non-biological surfaces, including food processing equipment and storage containers. Subsequently, they can contaminate food by forming a biofilm, thereby causing serious food safety problems. In this project, the natural antibacterial agent...
Fri, 09/18/2020 - 02:04
An increase in the production and usage of gold nanoparticles (AuNPs) triggers the necessity to focus on their impact on ecosystems. Therefore, the purpose of this study was to investigate the acute toxicity of AuNPs and ionic gold (Au (III)) to organisms representing all trophic levels of the aquatic ecosystem, namely producers (duckweed Lemna minor), consumers (crustacean Daphnia magna, embryos...
Fri, 09/18/2020 - 00:01
Botulinum neurotoxins (BoNTs) can be used therapeutically to treat a wide range of neuromuscular and neurological conditions. A collection of natural BoNT variants exists which can be classified into serologically distinct serotypes (BoNT/B), and further divided into subtypes (BoNT/B1, B2, …). BoNT subtypes share a high degree of sequence identity within the same serotype yet can...
Fri, 09/18/2020 - 00:00
Forty-eight Pasteurella multocida isolates were recovered from porcine pneumonic lungs collected from farms in “Castilla y León” (north-western Spain) in 2017–2019. These isolates were characterized for their minimal inhibition concentrations to twelve antimicrobial agents and for the appearance of eight resistance genes: tetA, tetB, blaROB1, blaTEM, ermA...
Fri, 09/18/2020 - 00:00
Antibiotic resistance has been reported since the 1940s in both human and veterinary medicine. Many years of monitoring milk samples in South Africa led to identification of a novel maltose-negative Staphylococcus aureus (S. aureus) strain, which appears to be an emerging pathogen. In this study, the susceptibility of this strain to antibiotics was evaluated over time, during diverse seasons in...
Thu, 09/17/2020 - 22:22
The objective of this study was to examine the effect of gamma irradiation (0, 2.5, and 5 kGy) on physico‐mechanical and structural characteristics of films based on Farsi gum‐carboxymethyl cellulose supplemented with Ziziphora clinopodioides essential oil (ZEO; 0%, 1%, and 2%) and lignocellulose nanofibers (LCNF; 0%, 1%, and 2%), and their application on fresh minced beef meat's shelf‐life...
Thu, 09/17/2020 - 22:20
In this study, total RNA was extracted from young leaves of maize. Reverse transcription‐PCR (RT‐PCR) method was used to obtain full‐length TGase gene. The amplified fragment was sequenced to have 1,605 bp. The gene consisted of 535 amino acid residues with a calculated molecular mass of 60.9 kD. It was identical to the published TGase gene (GenBank NO.AJ421525). The TGase fragment was cloned...
Thu, 09/17/2020 - 22:20
Free radicals produced during oxidation on the one hand and food contaminated with food source microorganisms on the other hand are serious threats to human health which increase the need to use natural compounds to replace synthetic and chemical substances used. In the present study, the antioxidant and antimicrobial activity of the cinnamon extract was investigated during hamburger meat storage...
Thu, 09/17/2020 - 16:00
Tuberculosis (TB) is one of the major causes of death related to antimicrobial resistance worldwide because of the spread of Mycobacterium tuberculosis multi- and extensively drug resistant (multi-drug resistant (MDR) and extensively drug-resistant (XDR), respectively) clinical isolates. To fight MDR and XDR tuberculosis, three new antitubercular drugs, bedaquiline (BDQ), delamanid, and...
Thu, 09/17/2020 - 16:00
Staphylococcus aureus is an opportunistic bacterium of the human body and a leading cause of nosocomial infections. Methicillin resistant S. aureus (MRSA) infections involving biofilm lead to higher mortality and morbidity in patients. Biofilm causes serious clinical issues, as it mitigates entry of antimicrobials to reach the etiological agents. It plays an important role in resilient chronic...
Thu, 09/17/2020 - 16:00
Despite the continuous emergence of multi-drug resistant pathogens, the number of new antimicrobials reaching the market is critically low. Natural product peptides are a rich source of bioactive compounds, and advances in mass spectrometry have achieved unprecedented capabilities for the discovery and characterization of novel molecular species. However, traditional bioactivity assay formats...
Thu, 09/17/2020 - 10:04
ABSTRACT Listeria monocytogenes is thought to colonize the brain using one of three mechanisms: direct invasion of the blood-brain barrier, transportation across the barrier by infected monocytes, and axonal migration to the brain stem. The first two pathways seem to occur following unrestricted bacterial growth in the blood and thus have been linked to immunocompromise. In contrast, cell-to-cell...
Thu, 09/17/2020 - 10:04
ABSTRACT Enterohemorrhagic Escherichia coli (EHEC) O157:H7 is a major cause of foodborne gastrointestinal illness. The adhesion of EHEC to host tissues is the first step enabling bacterial colonization. Adhesins such as fimbriae and flagella mediate this process. Here, we studied the interaction of the bacterial flagellum with the host cell’s plasma membrane using giant unilamellar vesicles...
Thu, 09/17/2020 - 10:04
This publication reports the availability of draft genome sequences of 171 Listeria monocytogenes strains isolated from various food-related sources from California between 2007 and 2017. All isolates contain at least two antimicrobial resistance genes.
Thu, 09/17/2020 - 10:04
Shiga toxin-producing Escherichia coli (STEC) is a foodborne pathogen transmitted from animals to humans through contaminated food. Cattle are the main reservoir of STEC, but their genetic diversity is still poorly characterized, especially regarding strains isolated in Portugal. We therefore present the draft genomic sequences of 12 STEC strains isolated from cattle in the north of Portugal.
Thu, 09/17/2020 - 06:23
Author(s): Silvia Guillén, María Marcén, Ignacio Álvarez, Pilar Mañas, Guillermo Cebrián
Wed, 09/16/2020 - 22:19
Significance and Impact of the Study: Campylobacter fetus subsp. venerealis (Cfv) is frequently associated with lowered fertility and abortion in ruminants. These infections are responsible for significant reproductive wastage in infected beef and dairy herds and may reduce gross profit margins up to 66%. In India, decreased fertility rates in productive animals are traditionally attributed to...
Wed, 09/16/2020 - 22:17
An important toxin‐antitoxin (TA) system hok/sok, encoded by R1 plasmid of Escherichia coli, is involved in post segregation killing of cells that have lost the plasmid. The lethal properties of hok protein have been utilized for the environmental containment of microbes and the development of potential vaccine candidates. We aim to demonstrate the potent anti‐microbial property of 19 amino acid...
Wed, 09/16/2020 - 16:00
PurposeLefamulin is a novel antibiotic approved by the U.S. Food and Drug Administration in 2019 for the treatment of community-acquired bacterial pneumonia (CABP). In this study we evaluated the in vitro antimicrobial activity of lefamulin in order to better understand its antibiogram.MethodsThe test strains were isolated from patients across China during the period from 2017 to 2019, including...
Wed, 09/16/2020 - 16:00
Salmonella Enteritidis (SE) is a facultative intracellular pathogen that colonizes the chicken gut leading to contamination of carcasses during processing. A reduction in intestinal colonization by SE could result in reduced carcass contamination thereby reducing the risk of illnesses in humans. Short chain fatty acids such as butyrate are microbial metabolites produced in the gut that exert...
Wed, 09/16/2020 - 16:00
Larval diets used for artificial rearing can have a significant effect on insect biology. The Queensland fruit fly (aka “Qfly”), Bactrocera tryoni (Froggatt) (Diptera: Tephritidae), is one of the greatest challenges for fruit growers in Australia. The sterile insect technique (SIT) is being developed to manage outbreaks in regions that remain free of Qfly and to reduce populations in regions...
Wed, 09/16/2020 - 16:00
Avian pathogenic Escherichia coli (APEC) is the causal agent of colibacillosis, one of the most common bacterial infections in the poultry sector. Antimicrobial susceptibility testing (AST) is essential for rational and prudent antimicrobial therapy. Subsequently, uniformity in test results from the various testing methodologies used in diagnostic laboratories is pivotal. The aim of this study...
Wed, 09/16/2020 - 16:00
The emergence of antimicrobial-resistant (AR) Salmonella has a major concern worldwide. This study was designed to determine the AR profiles and serovars distribution of Salmonella enterica isolated from different breeds of breeder chickens in the province of Henan, China. For this, 2,139 dead embryo samples were collected from 28 breeder chicken hatcheries, representing two domestic and four...
Wed, 09/16/2020 - 16:00
Regulation of the environmental stress response and virulence of Shigella flexneri may involve multiple signaling pathways; however, these mechanisms are not well-defined. In bacteria, small regulatory RNAs (sRNAs) regulate bacterial growth, metabolism, virulence, and environmental stress response. Therefore, identifying novel functional sRNAs in S. flexneri could help elucidate pathogenic...
Wed, 09/16/2020 - 12:01
Polychlorinated biphenyls (PCBs) are ubiquitously detected and have been linked to metabolic diseases. Gut microbiome is recognized as a critical regulator of disease susceptibility; however, little is known how PCBs and gut microbiome interact to modulate hepatic xenobiotic and intermediary metabolism. We hypothesized the gut microbiome regulates PCB-mediated changes in the metabolic...
Wed, 09/16/2020 - 10:04
ABSTRACT The bacterial and fungal community involved in ambrosia beetle fungiculture remains poorly studied compared to the famous fungus-farming ants and termites. Here we studied microbial community dynamics of laboratory nests, adults, and brood during the life cycle of the sugarcane shot hole borer, Xyleborus affinis. We identified a total of 40 fungal and 428 bacterial operational taxonomic...
Wed, 09/16/2020 - 08:02
by Pankaj Dhaka, Satya Veer Singh Malik, Jay Prakash Yadav, Manesh Kumar, Sukhadeo B. Barbuddhe, Deepak B. Rawool Coxiella burnetii is a highly infectious zoonotic pathogen infecting wide range of mammals, including humans. In the present study, a total of 711 blood samples from bovines [cattle (n = 543) and buffaloes (n = 168)] from eight farms at different geographical locations in India were...
Wed, 09/16/2020 - 06:14
Author(s): Abraham Fikru Mechesso, Dong Chan Moon, Su-Jeong Kim, Hyun-Ju Song, Hee Young Kang, Seok Hyeon Na, Ji-Hyun Choi, Ha-Young Kim, Soon-Seek Yoon, Suk-Kyung Lim Food-producing animals are considered a leading source of human Salmonella infections in Korea. However, there is a lack of comprehensive and up-to-date data regarding the diversity and resistance profiles of Salmonella serotypes...
Wed, 09/16/2020 - 06:14
Author(s): Shen Yang, Jian Li, Jude Juventus Aweya, Zijin Yuan, Wuyin Weng, Yueling Zhang, Guang-Ming Liu Antimicrobial peptides are being explored for use as food preservatives to prevent foodborne diseases. In this study, bioinformatics tools were used to screen potential antimicrobial amino acid sequences from the whey acidic protein (WAP) of large yellow croaker (Larimichthys crocea). A novel...
Tue, 09/15/2020 - 16:01
In this work, we report the isolation and detailed functional characterization for the new non-ribosomally synthesized antibiotic 5812-A/C, which was derived from metabolites of Streptomyces roseoflavus INA-Ac-5812. According to its chemical structure, the studied 5812-A/C preliminary is composed of a cyclic peptide part covalently bounded with an arabinose residue. N-terminal amino acid...
Tue, 09/15/2020 - 16:01
BackgroundEnterobacter cloacae is an opportunistic pathogen which is responsible for serious nosocomial infections. A gene which plays an important role in resistance to carbapenems is the New Delhi metallo-β-lactamase 1 (NDM-1). Currently, the spread of NDM-1-producing E. cloacae strains is a serious public threat.MethodsA multidrug-resistant E. cloacae ssp. dissolvens strain CBG15936 was...
Tue, 09/15/2020 - 16:01
Background: We conducted this retrospective study to reveal the accuracy of metagenomic next-generation sequencing (mNGS) for diagnosing osteoarticular infections from fresh abscess specimens obtained from patients in an HIV-naive population.Methods: We retrospectively analyzed hospital records at three participating TB-specialized hospitals for patients admitted with suggestive diagnoses of...
Tue, 09/15/2020 - 10:03
Members of the small multidrug resistant (SMR) efflux pump family known as SugE (more recently renamed to Gdx) are known for their narrow substrate selectivity to small guanidinium (Gdm+) compounds and disinfectant quaternary ammonium compounds (QACs). Gdx members have been identified on multidrug resistant plasmids in Gram-negative bacilli, but their functional role remains unclear as few have...
Mon, 09/14/2020 - 22:18
Clostridium difficile (C.difficile) can cause antibiotic‐associated diarrhea or pseudo‐membranous colitis in humans and animals. Currently, the various methods such as microbiological culture,cytotoxic assay, ELISA and PCR have been used to detect Clostridium difficile infection (CDI). These conventional methods, however, require long detection time and professional staff. The paper is to...

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