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Nanoparticles (NPs) that can activate macrophages infected with the tuberculosis causative pathogen Mycobacterium tuberculosis, could be an effective host directed therapy for the disease. In this study, curdlan was conjugated to poly(lactic-co-glycolic acid) (PLGA) to produce immunotherapeutic NPs. Various physicochemical characterizations were used to evaluate the curdlan-PLGA copolymer and the NPs. Molecular dynamics and simulation studies were used to characterize the interaction between curdlan, on the polymer and on NPs, with the Dectin-1 macrophage receptor. NPs with varying curdlan densities were evaluated for their effects on the production of pro- and anti-inflammatory cytokines in M. tuberculosis infected RAW264.7 macrophages. The killing efficacy of the NPs against intracellular M. tuberculosis was assessed. Physicochemical characterization of the curdlan-PLGA copolymer and NPs indicated successful formation of curdlan-PLGA copolymer and NPs of varying curdlan density (0 - 8% w/w) had sizes between 330 – 453 nm. Modelling studies showed curdlan to have a strong affinity for Dectin-1. Cytotoxicity assays showed the NPs to be non-toxic over 72 h. The proinflammatory cytokine TNF-α was found to be significantly upregulated by the NPs. The NPs reduced intracellular M. tuberculosis burden over 72 h. These NPs are a promising host directed therapy for intracellular eradication of M. tuberculosis.

This study assessed biofilm production ability (BPA) and other microbiological features of Streptococcus canis strains. Companion animal-origin 40 strains from each year (2015/2017) were randomly selected with the host information, and three blood-origin strains from 2 humans/1 dog were included. We measured BPA using crystal violet staining, along with S. canis M-like protein (SCM) allele typing, sequence type (ST) determination, antimicrobial resistance (AMR) phenotyping/genotyping, and virulence-associated gene profiling (gbp-ap1-fp1-brp). BPA measurements revealed that 35 strains with BPA and 48 strains without BPA. There was association of the producer with isolation year (2017). We found association between the non-producer and SCM allele 1/ST9: there was association of the producer with SCM allele 10/ST21. We observed correlation between the producer and presence of AMR genotypes. There was association between the producer and ap1 detection and between non-producer and gbp detection. Our observations suggest the correlation between the producer and other microbiological features (isolation year/SCM allele type 10/ST21/presence of AMR genotypes/ap1 detection).

The aim of this study was to investigate the clinical features, distribution and antimicrobial susceptibility of Nocardia species isolated from pulmonary nocardiosis cases in tertiary hospital in China. The species were collected from January 1, 2018 to May 31, 2019 and identified using MALDI-TOF MS or PCR. Antimicrobial susceptibility testing was performed using the broth microdilution method. Within the 44 Nocardia species, N. farcinica was the most frequently identified species (n = 36), followed by N. nova (n = 5), N. otitidiscaviarum (n = 1), N. cyriacigeorgica (n = 1), and N. transvalensis (n = 1). The top three predisposing factors of pulmonary nocardiosis were chronic obstructive pulmonary disease (45.5%), hypertension (34.1%), and tuberculosis (31.8%). All 44 Nocardia strains were susceptible to amikacin, trimethoprim / sulfamethoxazole, and linezolid. The resistance rates of Nocardia to amoxicillin-clavulanic acid, ciprofloxacin, clarithromycin, ceftriaxone, tobramycin, and imipenem were 4.5%, 9.1%, 79.5%, 72.7%, 63.6%, and 38.6%, respectively. Two Nocardia strains had decreased sensitivity to trimethoprim / sulfamethoxazole. In conclusion, N. farcinica was the most frequently isolated Nocardia species in the First Hospital of Changsha. All isolated clinical Nocardia strains showed susceptible to amikacin, trimethoprim / sulfamethoxazole, and linezolid, suggesting that these drugs can be primary therapeutic choices for treating Nocardia infections.

Background: Nosocomial bacterial infections from carbapenem-resistant Klebsiella pneumoniae (CRKP) are associated with high mortality in neurosurgical patients. This study examined the post-neurosurgical meningitis outbreak caused by CRKP of patients with nervous system tumours，and analysed the molecular characteristics of the causative strain.Methods: Neurosurgical cancer patients with meningitis caused by CRKP between 2017–2019 were retrospectively analysed. Identification of strains and antimicrobial susceptibilities was conducted using BD Phoenix-100, 16S rRNA gene sequencing and broth microdilution. Multilocus sequence typing (MLST) and pulsed-field gel electrophoresis (PFGE) were used to identify the subtypes of K. pneumoniae. The genotype correlation, resistance genes and plasmid of isolates were assessed by whole-genome sequencing (WGS).Results: Isolates were resistant to almost all of the tested antimicrobial agents except polymyxin and tigecycline. The PFGE and MLST revealed all isolates were the same strain - ST11–while WGS phylogenetic analysis indicated they were closely related. The isolates harboured blaKPC-2 and an IncFII-type plasmid; the blaKPC-2 gene had a similar genetic environment across isolates.Conclusions: The results of molecular analysis showed that ST11 and IncFII-type plasmid in CRKP have close correlations and indicate a long-term retrospective genomic study throughout the hospital for KPC-producing K. pneumoniae is necessary.

Escherichia coli is a pathogen associated with infections in piglets in the post-weaning phase, its pathogenicity is related to the animal's susceptibility to bacterial enterotoxins. The objective of the present study was to determine the EOs activity against E. coli strain, in the form planktonic and sessile. Although the Disc-Diffusion tests to determine the Minimum Inhibitory Concentration, do not fully corroborate with the other analyzes of this study, it was noticed bacteria inhibition. The EOs were prepared at 0.4%, 0.8% and 1.0% for tests. The tested EOs were effective against E. coli planktonic cells (p

Brucella spp. are facultative intracellular pathogens that invade, survive and proliferate in numerous phagocytic and non-phagocytic cell types, thereby leading to human and animal brucellosis. Outer membrane proteins (Omps) are major immunogenic and protective antigens that are implicated in Brucella virulence. A strain deleted of the omp16 gene has not been obtained which suggests that the Omp16 protein is vital for Brucella survival. Nevertheless, we previously constructed an omp16 conditional deletion strain of Brucella, ΔOmp16. Here, the virulence and immune response elicted by this strain were assessed in a mouse model of infection. Splenomegaly was significantly reduced at two weeks post-infection in ΔOmp16-infected mice compared to infection with the parental strain. The bacterial load in the spleen also was significantly decreased at this post-infection time point in ΔOmp16-infected mice. Histopathological changes in the spleen were observed via hematoxylin-eosin staining and microscopic examination which showed that infection with the ΔOmp16 strain alleviated spleen histopathological alterations compared to mice infected with the parental strain. Moreover, the levels of humoral and cellular immunity were similar in both ΔOmp16-infected mice and parental strain-infected mice. The results overall show that the virulence of ΔOmp16 is attenuated markedly, but that the immune responses mediated by the deletion and parental strains in mice are indistinguishable. The data provide important insights that illuminate the pathogenic strategies adopted by Brucella.

Tetanus is a potentially fatal public health illness resulted from the neurotoxins generated by Clostridium tetani. C. tetani is not easily culturable and culturing the relevant bacteria from infected wounds has rarely been useful in diagnosis; PCR-based assays can only be conducted at highly sophisticated laboratories. Therefore, a real-time recombinase polymerase amplification assay (Exo-RPA) was constructed to identify the fragments of the neurotoxin gene of C. tetani. Primers and the exo probe targeting the conserved region were designed, and the resulting amplicons could be detected in less than 20 min, with a detection limit of 20 copies/reaction. The RPA assay displayed good selectivity, and there were no cross-reactions with other infectious bacteria common in penetrating wounds. Tests of target-spiked serum and pus extract revealed that RPA is robust to interfering factors and has great potential for further development for biological sample analysis. This method has been confirmed to be reliable for discriminating between toxic and nontoxic C. tetani strains. The RPA assay dramatically improves the diagnostic efficacy with simplified device architecture and is a promising alternative to real-time PCR for tetanus detection.

Clostridioides difficile infection (CDI) is a significant cause of hospital-acquired and antibiotic-mediated intestinal diseases and is a growing global public health concern. Overuse of antibiotics and their effect on normal intestinal flora has increased the incidence and severity of infections. Thus, the development of new, effective, and safe treatment options is a high priority. Here, we report a new probiotic strain, Bacillus amyloliquefaciens (BA PMC-80), and its in vitro/in vivo anti-C. difficile effect as a prospective novel candidate that can replace the use of conventional antibiotics. BA PMC-80 showed a significant anti-C. difficile effect on co-culture assay and its cell-free supernatant (CFS) also exhibited a considerable anti-C. difficile effect with an 89.06 µg/mL 50% minimal inhibitory concentration in broth microdilution assay. The CFS was stable and equally functional under different pH, heat, and proteinase treatments. It also exhibited a high sensitivity against current antibiotics and no toxicity in sub-chronic toxicity in hamsters. Finally, BA PMC-80 showed a moderate effect in a hamster CDI model with reduced infection severity and delayed death. However, further studies are required to optimize the treatment condition of the hamster CDI model for better efficacy and identify the antimicrobial compound produced by BA PMC-80.

За останні роки проблема розвитку резистентності патогенних мікроорганізмів до основних груп антибактеріальних препаратів переросла з медичної у вагому соціально-економічну. Можливість набуття патогенними мікроорганізмами резистентності до основних груп антибактеріальних препаратів пов’язана зі здатністю бактерій набувати нової генетичної інформації. Ключовим фактором поширення резистентності є здатність бактерій передавати цю інформацію не тільки спадково, а й під час безпосереднього контакту однієї бактерії з іншою за допомогою плазмід. Провідними біохімічними механізмами резистентності є посилення експресії генів і синтез білків (на які діє антибіотик) зі зміною їх структури, синтез бета-лактамаз, які інактивують антибіотик, активне виведення (ефлюкс) антибіотика з мікробної клітини, зниження проникності для антибіотика клітинної мембрани бактерії, формування метаболічного «шунта» та ін.Основними шляхами запобігання антибіотикорезистентності та її подолання вважають запобігання поширенню антибіотикорезистентних збудників та раціональне застосування антибіотиків. У нашій роботі висвітлені сучасні уявлення про механізми розвитку резистентності патогенних мікроорганізмів до основних груп антибактеріальних препаратів і шляхи подолання цієї актуальної проблеми.

Introducción: El objetivo final de la terapia endodóntica es la eliminación de microorganismos en el interior del conducto radicular. Algunas bacterias pueden sobrevivir a esta terapia; entre las comúnmente detectadas en fallas endodónticas se encuentra el E. faecalis. Los cementos biocerámicos se presentan como una alternativa eficiente en la terapia de endodoncia debido a su capacidad de sellado y sus propiedades antimicrobianas. Métodos: Estudio experimental in vitro, en el que se sembró la bacteria (E. faecalis) en una caja de Petri, se tomaron de 5 a 10 cepas y se disolvieron en caldo de Mueller Hinton, para luego depositar el inóculo más el cemento en diferentes concentraciones en una placa de 96 pozos y medir el nivel de absorbancia de cada muestra en un espectrofotómetro. Para el análisis estadístico se utilizaron las pruebas no paramétricas de Mann-Whitney y Kruskal Wallis. Resultados: Al comparar de dos en dos los datos obtenidos no se obtuvieron datos esta-dísticamente significativos, pero al comparar las diferentes concentraciones de ambos cementos se obtuvo que el cemento de Grossman al 2 % tiene mayor efecto antimicrobiano. Conclusión: No hay diferencia significativa en la actividad antimicrobiana del MTA Fillapex® y el cemento de Grossman contra el E. faecalis, pero al comparar el cemento de Grossman al 2 %, este tiene mayor efecto antimicrobiano en comparación con el mismo cemento a diversas concentraciones.

Антибіотик-асоційована діарея залишається актуальною проблемою медицини. У нашому спостереженні діарея на тлі антибактеріальної терапії спостерігалася в 10 % пацієнтів. Антибіотики з групи цефалоспоринів 3-го покоління викликають дисбіотичні порушення в кишечнику переважно за рахунок росту умовно-патогенної флори (грибів роду Candida) та E.coli з гемолітичними властивостями. Вживання харчового функціонального продукту Субалін не лише зменшує негативний вплив антибіотиків на нормофлору кишечника, а й сприяє ліквідації дисбіотичних порушень, що вже існують. На нашу думку, для повного відновлення кількісного та якісного складу мікрофлори курс пробіотичних препаратів повинен перевищувати тривалість антибактеріальної терапії на 7–10 днів, але це потребує проведення додаткових досліджень.

A total of 244 Candida albicans isolates recovered from vulvovaginal candidiasis (VVC) patients in Suzhou, Eastern China, were investigated. According to CLSI documents M27-A4 and M59-3ed/M60-2ed, the MIC geometric means of nine antifungals in increasing order were micafungin (0.048 mg/L), anidulafungin (0.132 mg/L), caspofungin (0.19 mg/L), itraconazole (0.23 mg/L), posaconazole (0.25 mg/L), voriconazole (0.28 mg/L), 5-flucytosine (0.44 mg/L), amphotericin B (0.49 mg/L) and fluconazole (2.01 mg/L) respectively. Of note, 6.5% (16/244) C. albicans isolates showed resistance mainly to anidulafungin (mono-echinocandin resistance), while voriconazole had the lowest susceptibility rate of 34.8% (85/244), followed by fluconazole 59.4% (145/244), respectively. All isolates were genotyped by allelic combination of 3 microsatellite markers (CEF3, CAIII and LOC4). A total of 129 different allelic genotypes were identified, in which seven different clades were recognized with a discriminatory power of 0.96. Genotypes A-D were present in 35% of the isolates. In conclusion, decrease in antifungal drug susceptibility to C. albicans isolates from VVC is alarming. Our findings revealed the genetic diversity of C. albicans isolates among VVC patients and provided insights into the molecular epidemiology of Candida infections in China.

Актуальність. Бойові поранення кінцівок, кількість яких стрімко зросла з 2014 року, часто ускладнюються розвитком хірургічної інфекції. Сучасною тенденцією є зростання частки неферментуючих грамнегативних паличок серед етіологічних чинників госпітальних хірургічних інфекційних ускладнень. Мета дослідження: обґрунтувати вибір раціональної антибактеріальної терапії та профілактики спричиненої цими мікроорганізмами госпітальної хірургічної інфекції поранень кінцівок. Матеріали та методи. У трьох військово-медичних клінічних центрах (міста Київ, Львів, Вінниця) проведено аналіз результатів бактеріологічних досліджень бойових поранень. Аналіз стійкості до антибіотиків та профілів резистентності проводили відповідно до рекомендацій EUCAST та національних рекомендацій з інфекційного контролю. Порівняння резистентності до окремих препаратів проводили за критерієм Пірсона χ2. Результати. Проаналізовано результати 326 бактеріологічних обстежень, з яких отримано дані про 378 мікроорганізмів. Частка паличок роду Acinetobacter та роду Pseudomonas сягає 40 % серед усього спектра контамінант бойових поранень кінцівок. За станом чутливості до різних хіміотерапевтичних препаратів більшість ізолятів належить до полірезистентних або штамів із розширеною резистентністю. Рекомендації з антибактеріальної терапії госпітальних хірургічних інфекцій, до яких входить монотерапія карбапенемами та комбінації з включенням цефалоспоринів та фторхінолонів, будуть неефективні. До тигецикліну, колістину B та фосфоміцину виявляє стійкість менше від 25 % ізолятів P.aeruginosa та Acinetobacter spp. Виявлено штами з однаковими комбінаціями детермінант стійкості, такі штами виявляються навіть у географічно віддалених госпіталях. ­Висновки. Полірезистентність мікроорганізмів, факти об’єднання штамів в однакові фенотипи резистентності, що виявляються в різних госпіталях, вказують на те, що сучасні бойові поранення контамінуються спорідненими клональними популяціями, які мають єдине госпітальне джерело походження. Розробляти заходи антибактеріальної терапії потрібно в масштабах усього лікувально-евакуаційного ланцюга, без урахування локальних особливостей резистентності.

У роботі узагальнені дані щодо властивостей Bacillus subtilis та їх застосування у клінічній практиці. Унікальність препарату Субалін обумовлена поєднанням здатності бацил пригнічувати ріст патогенної та умовно-патогенної флори та виробляти інтерферон, завдяки чому препарат проявляє антибактеріальну, противірусну та імуномодулюючу дію. Застосування препарату разом з антибіотиком дозволяє досягти високої клінічної ефективності, максимальної ерадикації збудників інфекцій, запобігає подальшим рецидивам.

We observed high rates of bloodstream infections (BSIs) following fecal microbiota transplantation (FMT) for graft-versus-host-disease (33 events in 22 patients). To trace the BSIs' origin, we applied a metagenomic bioinformatic pipeline screening donor and recipient stool samples for bacteremia-causing strains in 13 cases. Offending strains were not detected in FMT donations. Enterococcus faecium, Escherichia coli, Pseudomonas aeruginosa, and Acinetobacter baumannii could be detected in stool samples before emerging in the blood. In this largest report of BSIs post-FMT, we present an approach that may be applicable for evaluating BSI origin following microbiota-based interventions. Our findings support FMT safety in immunocompromised patients but do not rule out FMT as an inducer of bacterial translocation.

Mouse hepatitis virus (MHV) is a murine coronavirus and one of the most important pathogens in laboratory mice. Although various strains of MHV have been isolated, they are generally excreted in the feces and transmitted oronasally via aerosols and contaminated bedding. In this study, we attempted to determine the basic reproduction numbers of three strains of MHV to improve our understanding of MHV infections in mice. Five-week-old female C57BL/6J mice were inoculated intranasally with either the Y, NuU, or JHM variant strain of MHV and housed with two naive mice. After 4 weeks, the presence or absence of anti-MHV antibody in the mice was determined by the enzyme-linked immunosorbent assay. We also examined the distribution of MHV in the organs of Y, NuU, or JHM variant-infected mice. Our data suggest that the transmissibility of MHV is correlated with viral growth in the gastrointestinal tract of infected mice. To the best of our knowledge, this is the first report to address the basic reproduction numbers among pathogens in laboratory animals.

Mushrooms represent a large family of fleshy fungi that have been of high interest since ancient ages due to their medicinal and nutritional importance. Therefore, it can represent a significant source of bioactive compounds in malaria control. The few numbers of studies on in vitro antiplasmodial and insecticidal properties of their extracts and chemical constituents led to interesting results reported in numerous scientific publications. This review aims to provide a comprehensive compilation of literature up to 2021 on the antiplasmodial, insecticidal as well as cytotoxic chemical constituents of medicinal mushrooms that can help in the management of malaria both against the parasite Plasmodium falciparum and the mosquitoe Anopheles stephensis acting as a vector of malaria through its bites. For this purpose, some searches have been done in some online libraries using keywords like Basidiomycete, mushroom, malaria, Plasmodium, Anopheles and antiplasmodial without language restriction. Among the reported compounds, 51 selected ones displayed significant antiplasmodial potency with IC50 values lower than 10 μM against P. falciparum strains sensitive or resistant to chloroquine. For instance, ganoderic acid AW1 demonstrated a strong antiplasmodial activity with IC50 of 257.8 nM against P. falciparum D6, while strong activities were displayed by ganoweberianones A (IC50 = 0.050 μM) and B (IC50 = 0.46 μM) against P. falciparum K1. Moreover, some mushroom methanol extracts demonstrated good larvicidal and ovicidal activities against Anopheles stephensis. This paper provides further insights into the development of new antiplasmodial drugs or new potent eco-friendly pesticides to control mosquito vectors.

This study evaluates the influence of mixed algal extract (Chlorella vulgaris, Euglena viridis and Spirulina platensis) on common carp Cyprinus Carpio, which infected infect with bacterial pathogen Aeromonas hydrophila. C. carpio was administered intraperitoneally with various doses such as methanol extract (0, 0,1, 1, 10 and 100 mg/kg). The immunological parameters of fish blood and serum samples (Neutrophil activity, Lysozyme activity, Serum myeloperoxidase intensity, Serum bactericidal activity, and Serum antiprotease activity) were investigated at 7, 14, 21, and 28 days of post-immunization. Fish had been tested by virulent A. hydrophila for 30 days after treatment and 14 days after infection were identified with mortalities. The findings showed that neutrophil levels, lysozyme activity, serum bactericidal activity, myeloperoxidase activity, and serum antiprotease activity significantly enhanced (pA. hydrophila disease infection. Results indicated that mixed algal extract in C. carpio positively impacts non-specific immune parameters and boosts disease tolerance to A. hydrophila infections.

У статті наведений аналіз літературних даних останніх років із питання формування та поширеності резистентності Helicobacter pylori до різних антибактеріальних препаратів, що використовуються для ерадикації цього мікроорганізму. Обговорені особливості терапевтичних підходів, шляхи подолання стійкості даної інфекції, вибір схем ерадикаційної терапії залежно від рівня резистентності Helicobacter pylori до антибактеріальних препаратів. Особливу увагу приділено питанню про поширеність антибіотикорезистентності Helicobacter pylori в дитячому віці.

Bacillus velezensis RB.IBE29 is a potent biocontrol agent with high chitinase activity isolated from the rhizosphere of black pepper cultivated in the Central Highlands, Vietnam. Genome sequences revealed that this species possesses some GH18 chitinases and AA10 protein(s); however, these enzymes have not been experimentally characterized. In this work, three genes were identified from the genomic DNA of this bacterium and cloned in Escherichia coli. Sequence analysis exhibited that the ORF of chiA consists of 1,203 bp and encodes deduced 45.46 kDa-chitinase A of 400 aa. The domain structure of chitinase A is composed of a CBM 50 domain at the N-terminus and a catalytic domain at the C-terminus. The ORF of chiB includes 1,263 bp and encodes deduced 47.59 kDa-chitinase B of 420 aa. Chitinase B consists of two CBM50 domains at the N-terminus and a catalytic domain at the C-terminus. The ORF of lpmo10 is 621 bp and encodes a deduced 22.44 kDa-AA10 protein, BvLPMO10 of 206 aa. BvLPMO10 contains a signal peptide and an AA10 catalytic domain. Chitinases A and B were grouped into subfamily A of family 18 chitinases. Amino acid sequences in their catalytic domains lack aromatic residues (Trp, Phe, Tyr) probably involved in processivity and substrate binding compared with well-known bacterial GH18 chitinases. chiB was successfully expressed in E. coli. Purified rBvChiB degraded insoluble chitin and was responsible for inhibition of fungal spore-germination and egg hatching of plant-parasitic nematode. This is the first report describing the analysis of the chitinase system from B. velezensis.

The Enterococcus faecalis (E. Faecalis) virulence factor plays an essential role in the persistence of root canal infection. Virulence factors of Enterococcus faecalis such as lipoteichoic acid, extracellular superoxide, gelatinase, hyaluronidase, and cytolysin are known to increase the ability of Enterococcus faecalis to induce inflammatory processes, colonization formation, and increase resistance. The virulence factor of E. faecalis is mediated by LTA, which has pattern recognition receptors for cytokine release, bone resorption and triggers apoptosis of osteoblasts, osteoclasts, periodontal connective tissue, macrophages, and neutrophils, which have implications for the occurrence of periradicular lesions. Lipoteichoic acid is also involved in producing D-alanine, which stimulates signals to other bacteria to form biofilms. The E. faecalis will change the balance of oxygen radical production in the periapical lesion, fragment collagen. The fight host's defense mechanisms that cause periapical damage and worsening bone loss. Furthermore, cytolysin will respond to changes in oxygen conditions in the depleting root canals for the dominance of E. faecalis against other bacteria. The energy needs of E. faecalis that assisted by hyaluronidase, which degrades hyaluronan dentin. İt has to produce disaccharide degradation products that can be transported and metabolized intracellularly. These materials hydrolyzing the substrate to obtain essential carbon for its growth. This article aims to describe the molecular aspect of E. faecalis virulence that is involved in root canal infections.

We highlight the need to include an analysis of the B-1 B cell subset to complement the characterization of the cell-mediated immune response to the Mycobacterium tuberculosis Beijing lineage. The literature describes the B-1 cell repertoire’s involvement in the cell-mediated response within granulomas, which is different from the classic antibody response B cells are generally associated with. Specifically, the B-1 B cell subset migrates from other compartments along with other cells to the infection site. We provide details to complement the reported results from Cerezo-Cortes et al.

Streptococcus uberis is a common cause of mastitis. The pathogenicity among different strains of S. uberis and the resultant host immune responses remain to be elucidated. Herein, we document immune responses among 3 strains of S. uberis, and preliminary explore whether and how intestinal immunity play a role in host anti-infection processes. Mice have been proved to be effective experimental animals for bovine mastitis, so utilizing a mouse intramammary infection model, we assay immune responses and gut flora changes of 3 S. uberis strains by histopathologic examination, RT-PCR, Western blot and 16s rDNA sequencing. We find that the immune responses among the 3 sequence type (ST) S. uberis strains may be linked to the hasA/B and lbp virulence genes, and the beta diversity of the intestinal may be independent of the ST type of S. uberis. Twenty phyla and 30 genera of intestinal flora are identified, Verrucomicrobia and Akkermansia being the most prominent phylum and genus respectively. These bacteria have strong anti-inflammatory and protective effects against S. uberis challenge. These datas provide a foundation for further studies to elucidate gut flora function and exploration of therapeutic targets for mastitis. This article is protected by copyright. All rights reserved.

Serum resistance is a poorly understood but common trait of some systemic disease pathogenic strains of bacteria. In this study, we analysed the role Escherichia coli type three secretion system 2 (ETT2) of avian pathogenic Escherichia coli (APEC) in serum resistance by bacteria survival number in serum culture, mRNA Seq and Tandem Mass Tag™ (TMT™) detection, lipopolysaccharide (LPS) extraction, and biofilm formation detection. We found that the ETT2 gene cluster deletion strain (ΔETT2) is more resistant to the killing effect of serum than wild type APEC40. The analysis of ΔETT2 compared to APEC40 in the transcriptomics and proteomics data showed that ETT2 has a negative effect in the ATP-binding cassette (ABC) translator system and quorum sensing system and a positive effect in purine metabolism. ETT2 may affect the LPS, biofilm, flagella, and fimbriae which may affect the serum resistance. These results could lead to effective strategies for managing the infection of APEC. The mRNA Seq data of this study are available in the Sequence Read Archive of the National Center for Biotechnology Information under the BioProject PRJNA757182, and proteomic raw data have been deposited under the accession number IPX0003420000 at iProX.

Diseases caused by harmful microorganisms pose a serious threat to human health. Safe and environment-friendly disinfectants are, therefore, essential in preventing and controlling such pathogens. This study aimed to investigate the antimicrobial activity and mechanism of a novel hydrogen peroxide and silver (H 2 O 2 -Ag + ) complex (HSC) in combatting Staphylococcus aureus ATCC 29213, Escherichia coli O157:H7 NCTC 12900 and Salmonella typhimurium SL 1344. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values against S. aureus were found to be 0.014 % H 2 O 2 -3.125 mg/L Ag + , while 0.028 % H 2 O 2 -6.25 mg/L Ag + for both E. coli and S. typhimurium . Results of the growth curve assay and time-kill trial suggest that the HSC could inhibit the growth of the tested bacteria, as 99.9 % of viable cells were killed following treatment at the 1 MIC for 3 h. Compared with Oxytech D10 disinfectant (0.25 % H 2 O 2 -5 mg/L Ag + ), the HSC exhibited better antibacterial efficacy at a lower concentration (0.045 % H 2 O 2 -10 mg/L Ag + ). The mechanism of antibacterial action of HSC was found including the disruption of the bacterial cell membrane, followed by entry into the bacteria cell to reduce intracellular adenosine triphosphate (ATP) concentration, and inhibit the activity of antioxidases, superoxide dismutase (SOD) and catalase (CAT). The enhanced bactericidal effect of hydrogen peroxide combined with silver indicates a potential for its application in environmental disinfection, particularly in the food industry.

Abutilon indicum Linn. (AI) is used in ayurvedic system and has shown potential to treat microbial infections. In the present study syringaldehyde was reported for the first time from the leaves of AI ethyl acetate extract and quantified by HPTLC analysis. Further, syringaldehyde showed significant broad spectrum anti-bacterial activity against Bacillus subtilis (BS) and Klebsiella pneumonia (KP). CLSM analysis also indicated at the ability of the molecule to inhibit biofilm formation in fungus Aspergillus fumigatus indicating its potent anti-fungal activity. Overall the molecule has potential to be used as anti-microbial compound with wide application.

Human oral microflora is one of the most complex microbial communities known. A consistent competitive environment in this niche necessitates the generation of bacteriocins or antimicrobial peptides (AMPs), which play a significant impact on niche ecology by inhibiting the growth of closely related inhabitants. In the current study, draft genomes of oral commensal Streptococcus salivarius strains were analyzed using various bioinformatic tools to design novel short antibiofilm peptides. The antimicrobial potency of peptides was predicted by using AMP database and Bactibase. Novel short peptides were designed, synthesized and evaluated against oral oppurtinistic pathogenic microbes. Synthetic short peptides (SSPs) displayed effective inhibition of biofilm formation by specific oral bacterial strains, indicating their potential applicability as targeted antibiofilm agents for variety of dental material surface coating applications.

Hard-shelled mussel (Mytilus coruscus) is a popular seafood in South Korea because of its delicacy and high nutritional value. Our study aimed to identify antimicrobial and heavy-metal resistance determinants in Aeromonas isolates from marketed hard-shelled mussel in South Korea. A total of 33 Aeromonas species were isolated, and antimicrobial disk diffusion test was done to observe antimicrobial resistance patterns. In addition, broth microdilution test was performed to determine resistance to heavy-metals. PCR amplification was done to detect resistance genes. High resistance to amoxicillin (100.0%), ampicillin (93.9%), rifampicin (78.8%), and cephalothin (48.5%) was observed where least resistance to other antimicrobials was also detected. In addition, the isolates showed high resistance to cadmium (Cd) (57.6%), and 42.4% and 27.3% were resistant to chromium (Cr) and copper (Cu). The occurrence of antimicrobial resistance genes, such as blaTEM, blaSHV, blaCTX-M, tetB, tetE, and intI1 genes, was observed in 9 (27.3%), 8 (24.2%), 8 (24.2%), 6 (18.2%), 5 (15.2%), and 9 (27.3%) isolates, respectively. Also, heavy-metal resistance genes, czcA, copA, and merA were detected in 17 (51.5%), 11 (33.3%), and 7 (21.2%) of the isolates, respectively. The results suggest that mussels are a reservoir of multidrug and heavy-metal-resistant Aeromonas spp.

Several species from the genus Quambalaria (order Microstromatales) cause diseases on eucalypts (Eucalyptus and related genera) both in plantations and natural ecosystems. We developed real-time quantitative PCR (qPCR) assays to rapidly detect and distinguish five Quambalaria species. The design of the species-specific qPCR assay for each species, Q. pitereka (PIT), Q. coyrecup (COR), Q. cyanescens (CYN), Q. pusilla (PUS), and Q. eucalypti (EUC), was based on the ITS region and was evaluated for specificity and sensitivity. The PIT, COR, and CYN qPCR assays could amplify as little as 10 fg µl−1 from pure cultures, whereas PUS and EUC qPCR assays could amplify 100 fg µl−1 of their target species. The PIT, COR, and CYN qPCR assays were further validated using naturally and artificially infected samples of their plant host Corymbia calophylla. These assays will be used for rapid diagnostics and future experiments on the infection process.

When infected by Helicobacter pylori, it often causes gastritis, gastric ulcer, or gastric cancer. Antibiotics are used to treat H. pylori infection, as they inhibit or kill H. pylori often ex-tending to reduce the incidences of gastric adenoma and cancer. However, H. pylori has developed drug resistance to many clinically used antibiotics over the years, thereby providing no warranty of successful treatment whenever H. pylori infection befalls. We report here that fucoidan from Sargassumhemiphyllum can effectively reduce infection of H. pylori without development of drug resistance. Fucoidan demonstrated a strong anti-inflammation activity in RAW264.7 cell model. Using AGS cell model, fucoidan decreased H. pylori adhesion to host cells and thus reduced its infection rate, especially in post-treatment where the infection rate was reduced to 40%. Mechanistically, fucoidan intervenes the proper functions of adhesion molecules BabA and AlpA of H. pylori. Moreover, fucoidan is able to significantly lower the total count of H. pylori and the levels of IL-6 and TNF-α in vivo. Added together, these convergent results suggest that fucoidan is an effective agent in a position to protect stomach from H. pylori infection by reducing its total count and induced inflammation.

Summary Heat acclimation (HA) is the best strategy to improve heat stress tolerance by inducing positive physiological adaptations. Evidence indicates that the gut microbiome plays a fundamental role in the development of HA, and modulation of gut microbiota can improve tolerance to heat exposure and decrease the risks of heat illness. In this study, for the first time, we applied 16S rRNA gene sequencing and untargeted liquid chromatography–mass spectrometry (LC‐MS) metabolomics to explore variations in the gut microbiome and faecal metabolic profiles in rats after HA. The gut microbiota of HA subjects exhibited higher diversity and richer microbes. HA altered the gut microbiota composition with significant increases in the genera Lactobacillus (a major probiotic) and Oscillospira alongside significant decreases in the genera Blautia and Allobaculum. The faecal metabolome was also significantly changed after HA, and among the 13 perturbed metabolites, (S)‐AL 8810 and celastrol were increased. Moreover, the two increased genera were positively correlated with the two upregulated metabolites and negatively correlated with the other 11 downregulated metabolites, while the correlations between the two decreased genera and the upregulated/downregulated metabolites were completely contrary. In summary, both the structure of the gut microbiome community and the faecal metabolome were improved after 28 days of HA. These findings provide novel insights regarding the improvement of the gut microbiome and its functions as a potential mechanism by which HA confers protection against heat stress., Evidence indicates that the gut microbiome plays a fundamental role in the development of HA. In this study, we applied 16S rRNA gene sequencing and untargeted liquid chromatography‐mass spectrometry (LC‐MS) metabolomics to explore variations in the gut microbiome and fecal metabolic profiles in rats after HA. Our study demonstrates for the first time that HA has a significant effect on the gut microbiome and fecal metabolome, and this may be a potential mechanism by which HA confers protection against heat stress.

The enormous chemical diversity and strain variability of prokaryotic protein glycosylation makes a large-scale exploration exceptionally challenging. Therefore, despite the universal relevance of protein glycosylation across all domains of life, the understanding of their biological significance and the evolutionary forces shaping oligosaccharide structures remains highly limited.Here, we report on a newly established mass binning glycoproteomics approach that establishes the chemical identity of the carbohydrate components and performs untargeted exploration of prokaryotic oligosaccharides from large-scale proteomics data directly. We demonstrate our approach by exploring an enrichment culture of the globally relevant anaerobic ammonium-oxidizing bacterium Ca. Kuenenia stuttgartiensis. By doing so we resolved a remarkable array of oligosaccharides, produced by two entirely unrelated glycosylation machineries targeting the same surface-layer protein (SLP) simultaneously. More intriguingly, the investigated strain also accomplished modulation of highly specialized sugars, supposedly in response to its energy metabolism—the anaerobic oxidation of ammonium —which depends on the acquisition of substrates of opposite charge. Ultimately, we provide a systematic approach for the compositional exploration of prokaryotic protein glycosylation, and reveal for the first time a remarkable balance between maximising cellular protection through a complex array of oligosaccharides and adhering to the requirements of the ‘metabolic lifestyle’.

The housekeeping sortase A (SrtA), a membrane-associated cysteine transpeptidase, is responsible for anchoring surface proteins to the cell wall peptidoglycan in Gram-positive bacteria. This process is essential for the regulation of bacterial virulence and pathogenicity. Therefore, SrtA is considered to be an ideal target for antivirulence therapy. In this study, we report that ML346, a compound with a barbituric acid and cinnamaldehyde scaffold, functions as an irreversible inhibitor of Staphylococcus aureus SrtA (SaSrtA) and Streptococcus pyogenes SrtA (SpSrtA) in vitro at low micromolar concentrations. According to our X-ray crystal structure of the SpSrtAΔN81/ML346 complex (Protein Data Bank ID: 7V6K), ML346 covalently modifies the thiol group of Cys208 in the active site of SpSrtA. Importantly, ML346 significantly attenuated the virulence phenotypes of S. aureus and exhibited inhibitory effects on Galleria mellonella larva infection caused by S. aureus. Collectively, our results indicate that ML346 has potential for development as a covalent antivirulence agent for treating S. aureus infections, including methicillin-resistant S. aureus.

Objective: Chemical investigation of the extract of sponge-derived fungus, Aspergillus niger, was performed by liquid chromatography coupled with QExactive mass spectrometry for the first time. Methods: A total number of 444 constituents were detected, 288 of which were identified positively or tentatively by the comprehensive utilization of accurate molecular weight and fragmentation information acquired from quadrupole orbitrap mass spectrometry. The identified compounds were divided into several types, namely, organic acid, alkaloid, saccharide, amino acid and cyclopeptide, terpenoid, polyketone, phenylpropanoid and other types of compounds. Systematic diagnostic ions and featured fragment patterns were summarized for each type, based on which 8 novel compounds belonging to the same type were characterized. Results: This work provided a rapid approach for the research of micro constituents in a complex analyte. Furthermore, the anti-tumor activity of the extract was evaluated on two different cell lines-Bel-7402 and Hela-S3 in vitro. The tumor-inhibitory effect of the Aspergillus niger extract was confirmed and may be mainly derived from its pro-apoptotic action. Moreover, the extract exerted more significant cytotoxicity in Bel-7402 cells than Hela-S3 cells, indicative of its selectivity on specific tumor cells. Conclusion: The evidence suggested that the Aspergillus niger extract may potentially serve as a remedy for the prevention and therapy of hepatic and breast carcinoma.

The transmission of certain bacteria from the mother's gut to the infant's gut via breast milk (BM) is critical for offspring's immune system development. Dysbiosis of the BM microbiota can be caused by a variety of reasons, which can be influenced by probiotics delivered via the enteromammary route. The goal of this study was to investigate the bacterium that can be transmitted from mother to infant's intestine during various lactation periods in 19 mother-child dyads. Bacterial transmission is most common during the colostrum phase when bacteria with certain amplicon sequence variants (ASVs) enter the newborn intestine and inhabit it permanently. We have established that anaerobic gut-associated bacteria, such as Faecalibacterium, Blautia and Lachnoclostridium, transfer from the mother to the infant's gut with lactation dependence using the idea of weighted transfer ratios. Streptococcus salivarius, Bifidobacterium longum, and Lactobacillus gasseri were transferred from the maternal gut to the BM, as well as from the BM to the newborn gut, dependent on different ASVs. These findings suggest that isolating key microorganisms from breast milk could be utilized to modify the microbiota of BM or newborns by giving the mother a probiotic or adding it to artificial milk to promote neonatal health.

Filamentous fungi are used as production hosts for various commercially valuable enzymes and chemicals including organic acids and secondary metabolites. We previously revealed that α-1,3-glucan and galactosaminogalactan (GAG) contribute to hyphal aggregation in the industrial fungus Aspergillus oryzae, and that production of recombinant protein in shake-flask culture is higher in a mutant lacking both α-1,3-glucan and GAG (AGΔ-GAGΔ) than in the parental strain. Here, we compared the productivity of the wild type, AGΔ-GAGΔ, and mutants lacking α-1,3-glucan (AGΔ) or GAG (GAGΔ) in batch culture with intermittent addition of glucose in a 5-L lab-scale bioreactor. The hyphae of the wild type and all mutants were dispersed by agitation, although the wild type and AGΔ formed small amounts of aggregates. Although mycelial weight was similar among the strains, the concentration of a secreted recombinant protein (CutL1) was the highest in AGΔ-GAGΔ. Evaluation of fluid properties revealed that the apparent viscosities of mycelial cultures of the wild type and AGΔ-GAGΔ decreased as the agitation speed was increased. The apparent viscosity of the AGΔ-GAGΔ culture tended to be lower than that of the wild-type strain at each agitation speed, and was significantly lower at 600 rpm. Overall, the lack of α-1,3-glucan and GAG in the hyphae improved culture rheology, resulting in an increase in recombinant protein production in AGΔ-GAGΔ. This is the first report of flow behavior improvement by a cell-surface component defect in a filamentous fungus.

The objectives of this investigation were a) to isolate bacteria from different foods (dairy products, fruits, and vegetables) and evaluate their probiotic potential and b) to select, identify, and characterize the strain with the highest probiotic potential. From 14 food samples, a total of 117 strains were isolated; however, only 42 (T1 to T42) showed the morphology (gram-positive, coco, and bacillar form) and were catalase- and oxidase-negative to be considered as a presumptive lactic acid bacteria (LAB). The antagonistic activity of the 42 strains was evaluated on Escherichia coli (O157:H7E09), Listeria monocytogenes (ATCC 19115), Staphylococcus aureus (ATCC 25923), and Salmonella enterica serotype Typhimurium (ATCC 14028). The strains with the highest antagonistic activity were nine isolates from the following: pulque (T1), sprouted beans (T26), ranchero cheese (T30, T31, T32, T33, T35, T36), and tenate cheese (T40) with inhibition zones from 17.0 ± 1.2 to 19.3 ± 2.8 mm. Based on the antagonistic activity against pathogenic bacteria and resistance to low pH and bile salts, strain T40 exhibited the highest probiotic potential. Using the 16S rRNA technique, strain T40 was identified as Lacticaseibacillus paracasei (the previous taxonomic nomenclature was Lactobacillus paracasei , prior to the nomenclature change in April 2020); this strain presented no resistance to ampicillin, gentamicin, erythromycin, and tetracycline. The antagonistic activity was evaluated in situ (fresh cheese) against pathogenic bacteria, evidencing the probiotic potential of L. paracasei . Finally, Lacticaseibacillus paracasei isolated from tenate cheese showed characteristics as a probiotic microorganism and high potential in food technology.

To disclose the antimicrobial susceptibility and wide adaptability of commonly occurring genotypes of Salmonella enterica serovar Typhimurium, the antimicrobial resistance and multilocus sequence t...

Multidrug-resistant (MDR) Staphylococcus aureus biofilms have emerged as a serious threat to human health. Recently, the development of antibiotic replacement therapy has gained much attention due to the potential application of bacteriocin. The present study sought to evaluate the antibacterial effect of bacteriocin XJS01 against MDR S. aureus, a previously reported bacteriocin against S. aureus strain 2612:1606BL1486 (S. aureus_26, an MDR strain demonstrated here), and its potential application as an antibiofilm agent. The minimum bactericide concentration of XJS01 against MDR S. aureus_26 was 33.18 μg/mL. XJS01 exhibited excellent storage stability and resistance against acid and reduced the density of established MDR S. aureus_26 biofilm. The hemolytic and HEK293T cytotoxicity activities of XJS01 and the histological analyses in mice confirmed its safety. Moreover, XJS01 effectively disrupted the MDR S. aureus_26 biofilm established on the skin wound surface and reduced the biofilm-isolated bacteria, thereby decreasing the release of pro-inflammatory cytokines and the proliferation of alternatively activated macrophages. Compared to mupirocin, XJS01 exhibited an excellent therapeutic effect on mice skin wounds, confirming it to be a potential alternative to antibiotics.

Pathogens can affect physiological and immunological reactions in immunocompromised animals and genetically engineered mice. Specifically, murine norovirus (MNV), Helicobacter, and intestinal protozoa are prevalent in rodent laboratory facilities worldwide. In this study, microbiological test results of the soiled bedding of sentinel mice showed the prevalence of MNV (50.9%, 28/55), Helicobacter hepaticus (29.1%, 16/55), Trichomonas spp. (14.5%, 8/55), and Entamoeba spp. (32.7%, 18/55). No single infections were detected as all cases were confirmed to have complex infections with two or four pathogens. In previous studies, the success rate of the cross-fostering method was not perfect; therefore, in this study, the entire mouse strain of the SPF rodent facility was rederived using embryo transfer. For up to three years, we confirmed that the results were negative with regular health surveillance tests. Embryo transfer was, thus, determined to be an effective method for the rederivation of specific pathogen free (SPF) barrier mouse facilities. This is the report for the effectiveness of embryo transfer as an example of successful microbiological clean-up of a mouse colony with multiple infections in an entire SPF mouse facility and embryo transfer may be useful for rederiving.

Introduction: Staphylococcus haemolyticus is an acquired opportunistic pathogen causing nosocomial infections. Our previous studies of S. haemolyticus showed a group of isolates that produced a sig...

Lactococcus lactis strains residing in the microbial community of a complex dairy starter culture named “Ur” are hosts to prophages belonging to the family Siphoviridae. L. lactis strains (TIFN1 to TIFN7) showed detectable spontaneous phage production and release (109 to 1010 phage particles/ml) and up to 10-fold increases upon prophage induction, while in both cases we observed no obvious cell lysis typically described for the lytic life cycle of Siphoviridae phages. Intrigued by this phenomenon, we investigated the host-phage interaction using strain TIFN1 (harboring prophage proPhi1) as a representative. We confirmed that during the massive phage release, all bacterial cells remain viable. Further, by monitoring phage replication in vivo, using a green fluorescence protein reporter combined with flow cytometry, we demonstrated that the majority of the bacterial population (over 80%) is actively producing phage particles when induced with mitomycin C. The released tailless phage particles were found to be engulfed in lipid membranes, as evidenced by electron microscopy and lipid staining combined with chemical lipid analysis. Based on the collective observations, we propose a model of phage-host interaction in L. lactis TIFN1 where the phage particles are engulfed in membranes upon release, thereby leaving the producing host intact. Moreover, we discuss possible mechanisms of chronic, or nonlytic, release of LAB Siphoviridae phages and its impact on the bacterial host. IMPORTANCE In complex microbial consortia such as fermentation starters, bacteriophages can alter the dynamics and diversity of microbial communities. Bacteriophages infecting Lactococcus lactis are mostly studied for their detrimental impact on industrial dairy fermentation processes. In this study, we describe a novel form of phage-bacterium interaction in an L. lactis strain isolated from a complex dairy starter culture: when the prophages harbored in the L. lactis genome are activated, the phage particles are engulfed in lipid membranes upon release, leaving the producing host intact. Findings from this study provide additional insights into the diverse manners of phage-bacterium interactions and coevolution, which are essential for understanding the population dynamics in complex microbial communities like fermentation starters.

The rise of antibiotic resistance has increased the need for alternative ways of preventing and treating enteropathogenic bacterial infection. Various probiotic bacteria have been used in animal and human. However, Saccharomyces boulardii is the only yeast currently used in humans as probiotic. There is scarce research conducted on yeast species commonly found in kefir despite its claimed potential preventative and curative effects. This work focused on adhesion properties, and antibacterial metabolites produced by Kluyveromyces lactis and Saccharomyces unisporus isolated from traditional kefir grains compared to Saccharomyces boulardii strains. Adhesion and sedimentation assay, slide agglutination, microscopy and turbidimetry assay were used to analyze adhesion of Salmonella Arizonae and Salmonella Typhimurium onto yeast cells. Salmonella growth inhibition due to the antimicrobial metabolites produced by yeasts in killer toxin medium was analyzed by slab on the lawn, turbidimetry, tube dilution and solid agar plating assays. Alcohol and antimicrobial proteins production by yeasts in killer toxin medium were analyzed using gas chromatography and shotgun proteomics, respectively. Salmonella adhered onto viable and non-viable yeast isolates cell wall. Adhesion was visualized using scanning electron microscope. Yeasts-fermented killer toxin medium showed Salmonella growth inhibition. The highest alcohol concentration detected was 1.55%, and proteins with known antimicrobial properties including cathelicidin, xanthine dehydrogenase, mucin-1, lactadherin, lactoperoxidase, serum amyloid A protein and lactotransferrin were detected in yeasts fermented killer medium. These proteins are suggested to be responsible for the observed growth inhibition effect of yeasts-fermented killer toxin medium. Kluyveromyces lactis and Saccharomyces unisporus have anti-salmonella effect comparable to Saccharomyces boulardii strains, and therefore have potential to control Salmonella infection.

Healthcare associated infections due to carbapenem-resistant Klebsiella pneumoniae (CRKP) are a major concern in Portuguese hospitals. Whole genome sequencing (WGS) can improve infection control, but this practice is not routinely used by hospital clinical laboratories in Portugal. We simulated the investigation of a CRKP outbreak based on WGS, with the aim of determining, in the minimum possible time, genetic relatedness between CRKP clinical and environmental isolates.Ten CRKP clinical isolates routinely obtained in the hospital laboratory were used. Forty environmental samples - from sinks and sink drains of ward rooms - were collected. Environmental samples were plated on selective media and presumptive CRKP colonies were isolated. Total DNA was extracted from all putative CRKP isolates and sequenced. Clonal relatedness was determined by multi-locus sequence typing and core genome single nucleotide polymorphism analysis; the presence of carbapenemase genes was evaluated.Clinical isolates were characterized in 48 hours: eight strains were confirmed as CRKP, of which six were of ST13 and carried blaKPC-3. Environmental samples results were obtained in six days: eight CRKP were isolated from which five were of ST13 and carried blaKPC-3. Clinical and environmental ST13 isolates were highly related: ten (of 11) isolates differed from each other in0.001% of 2 172 367 core nucleotides.WGS can be used as a high-resolution effective tool to investigate healthcare associated infections and track routes of dissemination in real-time.In Portugal, routine use of WGS to improve infection control could thrive through collaborative initiatives between hospitals and research institutes.Introdução: As infeções associadas aos cuidados de saúde por Klebsiella pneumoniae resistente aos carbapenemos (CRKP) são uma preocupação nos hospitais portugueses. A sequenciação total do genoma [whole genome sequencing (WGS)] pode ajudar no controlo de infecção, mas esta prática não é comummente utilizada nos laboratórios clínicos hospitalares em Portugal. O objetivo deste estudo foi simular a investigação de um surto causado por CRKP, utilizando WGS. Pretendia-se testar a utilização desta técnica e determinar, no menor tempo possível, relações genéticas entre estirpes. Material e Métodos: Foram analisados dez isolados clínicos de CRKP. Foram obtidas quarenta amostras ambientais que foram inoculadas em meio seletivo para isolamento de colónias sugestivas de CRKP e depois sequenciado o DNA total dos isolados presumptivamente identificados como CRKP A relação clonal entre as estirpes foi determinada por multi-locus sequence typing e análise de single nucleotide polymorphisms no genoma core. Foi determinada a presença de genes de carbapenemases. Resultados: Os isolados clínicos foram caraterizados em 48 horas: oito isolados foram confirmados como CRKP. A maioria pertencia ao ST13 (n = 6) e possuía o gene blaKPC-3. As amostras ambientais foram caraterizadas em seis dias: foram isoladas oito CRKP, das quais cinco eram ST13 e continham o gene blaKPC-3. Os isolados ST13 clínicos e ambientais eram muito semelhantes entre si: dez dos 11 isolados diferiam entre si em menos de 0,001% dos 2 172 367 nucleótidos core analisados. Discussão: A sequenciação total do genoma pode ser usada como uma ferramenta útil para investigar infecções nosocomiais e rastrear cadeias de disseminação em tempo real. Conclusão: Em Portugal, o uso desta técnica em controlo de infecção pode ser implementado através de colaborações entre hospitais e institutos de investigação.

To treat infections caused by Candida albicans, azoles, polyenes, and echinocandins are used. However, resistance occurs against all three, so there is an urgent need for new antifungal drugs with a novel mode of action. Recently, it became clear that central metabolism plays an important role in the virulence of C. albicans. Glycolysis is, for example, upregulated during virulence conditions, whereas the glyoxylate cycle is important upon phagocytosis by host immune cells. These findings indicate that C. albicans adapts its metabolism to the environment for maximal virulence. In this review, we provide an overview of the potency of different central metabolic pathways and their key enzymes as potential antifungal drug targets.

A series of some new pyrazole-substituted 7H-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazines was synthesized in this study. The structures of target substances were confirmed by using 1H and 13С NMR spectroscopy, mass spectrometry and elemental analysis. The synthesized compounds have been evaluated for antimicrobial activity against five bacterial strains (Escherichia coli, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, Staphylococcus aureus) and two fungal strains (Candida albicans and Cryptococcus neoformans). The antimicrobial screening studies of synthesized substances established that 2 of 12 compounds show pronounced antibacterial activity against the strain Staphylococcus aureus.

Peach scab caused by Venturia carpophila is one of the most destructive fungal diseases of peach worldwide, and it seriously affects peach production. Until now,the infectious process and pathogenesis of V. carpophila on peach have remained unclear. Here we present the infection behavior of V. carpophila at the ultrastructural and cytological levels in peach leaves with combined microscopic investigations (i.e., light microscopy, confocal laser scanning microscopy, scanning electron microscopy, and transmission electron microscopy). V. carpophila germinated at the tip of conidia and produced short germ tubes on peach leaf surfaces at 2 days post inoculation (dpi). At 3 dpi, swollen tips of germ tubes differentiated into appressoria. At 5 dpi, penetration pegs produced by appressoria broke through the cuticle layer and then differentiated into thick subcuticular hyphae in the pectin layer of the epidermal cell walls. At 10 dpi, the subcuticular hyphae extensively colonized in the pectin layer. The primary hyphae ramified into secondary hyphae and proliferated along with the incubation. At 15 dpi, the subcuticular hyphae divided laterally to form stromata between the cuticle layer and the cellulose layer of the epidermal cells. At 30 dpi, conidiophores developed from the subcuticular stromata. Finally, abundant conidiophores and new conidia appeared on leaf surfaces at 40 dpi. These results provide useful information for further a understanding of V. carpophila pathogenesis.

Cystic fibrosis is characterized by abnormal mucous secretions in the lungs that favor the proliferation of colonizing bacteria, with Pseudomonas aeruginosa and Staphylococcus aureus being the most isolated, however, other less known species could also have an impact on the health of the patient. Here we demonstrate the isolation and antibiotic resistance profiles of Inquilinus limosus, a rarely reported multidrug resistant bacterium, and compare them to a co-infectant strain of Pseudomonas aeruginosa. Likewise, we found that co-infection with both bacteria promotes increased formation of neutrophil extracellular traps, which can have an impact on the disease severity and make treatment difficult.