Search Results (151)

Background:Enterococcus spp. is the third leading cause of healthcare-associated infections in the American continent, often because of the virulence factors that protect the bacterium against host defenses and facilitate tissue attachment and genetic material exchange. In addition, vancomycin, considered a last-resort treatment, has shown reduced efficacy in Enterococcus spp. strains. However, the relationship between bacterial resistance and virulence factors remains unclear. This study intends to evaluate the prevalence of glycopeptide-resistant genotypes and virulence factors in Enterococcus spp. strains. Methods: Over six months, 159 Enterococcus spp. strains causing nosocomial infections were analyzed. Multiplex PCR was performed to identify species, glycopeptide-resistant genotypes, and 12 virulence factors. Results: The most abundant species identified were Enterococcus faecalis and E. faecium. Vancomycin resistance was observed in 10.7% of the isolates, and the vanA genotype was present in 47% of resistant samples. The main virulence factors detected were acm (54%), which is related to cell adhesion; gel E (66%), a metalloproteinase linked to tissue damage; and the sex pheromones cpd (64%) and ccf (84%), which are involved in horizontal gene transfer. A significant association was found between the prevalence of acm, ccf, and cpd in VRE isolates, indicating the potential dissemination of genes to emerging strains via horizontal gene transfer. In addition, a new E. faecium, which displayed five virulence factors and harbored the vanA sequence type, was identified and registered as ST2700. Conclusions:Enterococcus faecalis and E. faecium are clinically critical due to multidrug resistance and virulence factors like acm, which aids host colonization. Genes ccf and cpd promote resistance spread via horizontal transfer, while the emerging ST2700 strain requires urgent monitoring to curb its virulent, drug-resistant spread. Full article

During field surveys carried out in 2021 at two farms in Lombardy (North Italy), leaf samples were collected from 113 plants (both symptomatic and asymptomatic) belonging to 18 medicinal and aromatic species. Amplification and nucleotide sequence analyses of the 16S rRNA gene revealed the presence of ‘Candidatus Phytoplasma solani’ (subgroup 16SrXII-A) in 69 plants (61% infection rate) belonging to 14 of the 18 examined species. Among the 14 infected species, only Nepeta cataria L. exhibited symptoms including leaf and stem reddening. Molecular typing analyses showed that ‘Ca. P. solani’ strains identified in this study constitute a genetically homogeneous population, carrying the stamp gene sequence variant St5 and the new vmp1 gene sequence variant Vm93. Phylogenetic analyses showed that ‘Ca. P. solani’ strain St5/Vm93 belongs to the cluster b-II, associated with the bindweed-related pathosystem. In silico-translated Vmp1 protein sequence alignment suggested that ‘Ca. P. solani’ strain St5/Vm93 could be generated by recombination events between ‘Ca. P. solani’ strains co-infecting the same host. The results suggested future research investigating the diffusion and the ecology of ‘Ca. P. solani’ strain St5/Vm93 in agroecosystems (including other crops), and its effect on the composition of biologically active compounds in aromatic and medicinal plants. Full article

Military Orders in the Iberian Peninsula in the Middle Ages were greatly involved in both the processes of conquest and subsequent transformation of the territories seized from Islamic rule. Evidence of this involvement is still visible today through solid and long-lasting buildings raised in response to the new needs of the dominant Christian society. The most significant were fortresses, and all their variants, followed by the temples of various sizes and categories. However, there were also other lesser-known constructions including mills, hospitals, houses of the commandery, and houses of agricultural domains. This study, based on written and archaeological sources, focuses on the constructions linked to the Military Orders, especially those of the Orders of Santiago, Calatrava, and St. John throughout the Kingdom of Castile between the 12th and 15th centuries. This analysis thus delves into the temporal sequence and regional variations of these features that not only led to a transformation of the landscape but also reflected changes in the framework of a particular type of society affected by power relations, technological evolution, available resources and wealth, as well as by its mentality and identity. Founded on data gleaned through basic research, this study thus attempts to reconstruct, among other aspects, this historical development by identifying the operational sequence which began with the procurement of raw materials, passing through the construction processes, and the application of different techniques. The study has likewise placed a special emphasis on the alarifes and the final results of their duties by analysing their choices of construction techniques and their functions. Full article

Background/Objectives: The global spread of carbapenemase-producing K. pneumoniae (CPKP) strains represent a severe public health threat due to very limited choice of antibacterial therapy. Cefiderocol, a novel siderophore-cephalosporin, may represent a new therapeutic option but resistance is increasingly being described. Our aim was to investigate in vitro cefiderocol susceptibility among CPKP strains in Hungary and assess correlations between resistance, carbapenemase types, and clonal lineages. Methods: The study was performed on 420 CPKP strains from 34 Hungarian healthcare institutes (HCIs) submitted to the National Reference Laboratory of Antimicrobial Resistance (March 2021 to April 2023). The disk diffusion method (Liofilchem, Via Scozia, Italy) was used for in vitro cefiderocol susceptibility testing (according to EUCAST guidelines). For molecular epidemiologic investigation, we used whole genome sequencing (Illumina MiSeq, 150 bp paired-end) and pulsed-field gel electrophoresis (PFGE). Carbapenemase gene type was determined by multiplex PCR. Statistical analysis was performed in R (v.4.2.0). Results: Dominant high-risk clones (ST147, ST395, ST258) exhibited regional distribution, with ST147/NDM-1 strains showing the highest cefiderocol resistance (75%). Overall resistance was 65%. Carbapenemase gene types occurred as follows: 35 bla_VIM, 53 bla_KPC, 57 bla_OXA-48-like, 153 bla_NDM, and 122 bla_OXA-48-like+bla_NDM. Cefiderocol resistance rates by carbapenemase type were 20%, 44%, 70%, and 75% in the case of bla_VIM, bla_OXA-48-like, bla_KPC, bla_NDM, and bla_OXA-48-like+bla_NDM. Conclusions: The results show a high prevalence of cefiderocol resistance in CPKP in Hungary, with different rates of resistance in different carbapenemase gene-carrying high-risk clones, highlighting the growing challenge in treating these infections. Full article

Proteins of the PF10950 family feature the DUF2775 domain of unknown function. The most studied are specific tissue (ST) proteins with tandem repeats, which are putative precursors of cyclopeptide alkaloids. Here, we study uncharacterised short ST (SST) proteins with the DUFF2775 domain by analysing 194 sequences from 120 species of 39 taxonomic families in silico. SST proteins have a signal peptide and their size and several other characteristics depend on their individual taxonomic family. Sequence analyses revealed that SST proteins contain two well-conserved regions, one resembling the ST repeat, which could constitute the core of cyclopeptide alkaloids. We studied the unique SST1 gene of Arabidopsis thaliana, which is adjacent to and co-expressed with a gene encoding a protein with a BURP domain, associated with cyclopeptide production. The empirical analysis indicated that the SST1 promoter is mainly activated in the roots, where most of the transcripts accumulate, and that the SST1 protein accumulates in the root vascular cambium. At the cellular level, SST fused to GFP appears in vesicles that co-localise with the endoplasmic reticulum and the vacuole. Thus, SSTs are a new type of PF10950 protein found in core eudicots with two conserved regions that could be involved in root biology. Full article

Carbapenem-resistant Pseudomonas aeruginosa (CRPA) is a significant opportunistic human pathogen, posing a considerable threat to public health due to its antimicrobial resistance and limited treatment options. The incidence of CRPA is high in the Philippines; however, genomic analysis of CRPA in this setting is limited. Here, we provide the phenotypic and molecular characterization of 35 non-duplicate CRPA obtained from three tertiary hospitals in Metro Manila, Philippines, from August 2022 to January 2023. Six sequence types (STs), including international high-risk clones ST111 and ST357, were identified. This article highlights the first report in the Philippines on the identification of P. aeruginosa harboring Klebsiella pneumoniae Carbapenemase-2 (KPC-2), coproduced with Verona Integron-encoded Metallo-beta-lactamase-2 (VIM-2) and Oxacillinase-74 (OXA-74). Notably, this is also the first report of KPC in the Philippines identified in P. aeruginosa. New Delhi Metallo-beta-lactamase-7 (NDM-7), coproduced with Cefotaxime-Munich-15 (CTX-M-15) and Temoneira-2 (TEM-2), was also identified from a novel ST4b1c. The relentless identification of NDM in the Philippines’ healthcare setting poses a significant global public health risk. The initial detection of the P. aeruginosa strain harboring KPC exacerbated the situation, indicating the inception of potential dissemination of these resistance determinants within P. aeruginosa in the Philippines. Full article

In the present study, we isolated S. canis from milk samples in a dairy farm with suspicions of subclinical mastitis. Milk samples testing positive on California Mastitis Test (CMT) were collected from different cows for bacteriological and genomic analyses to identify the causative pathogen, and somatic cell counts (SCC) were determined. A multiplex qPCR assay was conducted to detect 15 potential pathogens, and all samples showed negative results. Conventional bacteriology procedures were performed; DNA of the bacterial strains was extracted, sequenced, and submitted to bioinformatic analysis. Three CMT positive milk samples showed SCC > 200 × 10³ cell/mL. However, these same three samples were positive for bacteria phenotypically identified as Streptococci, and the strains were confirmed as S. canis using MS MALDI-TOF methodology. In susceptibility testing, resistance against tetracycline was detected, revealing a potential chronic infection in one cow, while the presence of the same bacteria was observed in two other cows. Genomic DNA from four S. canis isolates, obtained in the first and second sampling, was sequenced. Genetic relationships revealed a unique sequence type (ST24). The gene (tetM) related with resistance to TE was highlighted. Although the association between S. canis and mastitis is not routinely detected, early diagnosis of bacterial infections and the study of the antimicrobial profile are crucial for effective therapy. Pets could act as a potential reservoir, so improving hygienic conditions is needed to prevent new infections. Full article

Streptococcus agalactiae, known as group B streptococci (GBS), colonizes the digestive and genitourinary tracts and causes neonatal diseases and infections in immunocompromised and elderly individuals. GBS neonatal disease prevention includes intrapartum antibiotic prophylaxis. We characterized 101 GBS isolates obtained from patients in João Pessoa, northeastern Brazil, owing to the need to develop and implement vaccines to prevent GBS infections. Capsular types were determined using multiplex-PCR, and antibiotic susceptibility profiles were determined using disc diffusion or the gradient strip method. Clonal diversity was evaluated using pulsed-field gel electrophoresis. Fourteen selected isolates had the genome sequenced and evaluated for virulence and resistance genes. The GBS population had high clonal diversity, with serotype Ia and V prevalence. Among the sequenced isolates, we detected antibiotic resistance genes (ant(6)-Ia, catA8, ermA, ermB, lsaE, lsnuB, mefA/msrD, tetM, tetO, and tetS), several virulence genes, and mobile genetic elements integrated into the chromosome. The most frequent Sequence Type (ST) was ST144, followed by ST196, ST28, ST19, ST12, ST23, ST103, and the new ST1983 (CC103). Phylogenetically, ST103 and ST1983 were distant from the other STs. Our data revealed highly virulent GBS strains in this population and a new ST that could be related to a zoonotic origin. Full article

The emergence of Salmonella enterica serotype Dublin (S. Dublin) presents significant challenges to animal and human health. We analyzed 109 S. Dublin isolates from bovine submissions to the Penn State Animal Diagnostic Laboratory between 2011 and 2022. Using whole genome sequencing, we assessed their phenotypic and genotypic resistance patterns and correlated these traits with case histories and pathology reports. Core-genome analysis identified cgSTs with similar allelic profiles between our isolates and those from the U.S. and Canada, while some cgSTs were unique to our study. Histopathologic findings suggest a predominance of respiratory and gastroenteric/hepatic lesions, aligning with the histopathological case definition for S. Dublin infection. Critically, all isolates were multidrug-resistant, particularly to ampicillin (87%), ceftiofur (89%), chlortetracycline (94%), oxytetracycline (94%), enrofloxacin (17%), florfenicol (94%), sulfadimethoxine (97%), and trimethoprim (20%). Plasmid genomic analysis unveiled distinct plasmid types including virulence, resistance, and hybrid plasmids, carrying unique compositions of virulence genes and antimicrobial resistance. These findings underscore the importance of managing calf movement to control the introduction and dissemination of new cgSTs in Pennsylvania and potentially nationwide. Furthermore, they emphasize the urgent need to mitigate S. Dublin transmission, combat antimicrobial resistance, and enhance surveillance efforts to effectively protect animal and human health. Full article

Background: Staphylococcus aureus is one of the most prevalent pathogens causing mastitis in dairy animals and represents a serious issue of public health concern due to its resistance against multiple antimicrobials. Objectives: This study assessed 101 S. aureus isolates obtained from quarter milk of animals with subclinical mastitis in the Ragusa area (Sicily, Italy). Methods: Antibiotic resistance against nine antibiotics was evaluated using the Kirby–Bauer method, and the Minimum Inhibitory Concentration (MIC) values were measured for oxacillin (OXA) and vancomycin (VA). Additionally, the isolates were genetically characterized through multiplex PCR to identify the presence of spa, mecA, mecC, pvl, vanA, vanB, and vanC genes, along with pulsed-field gel electrophoresis analysis and multi-locus sequence typing (MLST). Results: The highest rates of antibiotic resistance were found against gentamicin (47.5%) and erythromycin (29.7%), with 86.1% of strains exhibiting resistance to at least two antimicrobials and 33.7% showing resistance to three antimicrobial classes. Furthermore, the results indicated that the presence of antibiotic resistance genes was not correlated with phenotypic resistance, and a phylogenetic analysis revealed varying phenotypic resistance profiles even within the same PFGE cluster. Lastly, alongside a new allelic profile ST 9471, MLST analysis identified five additional STs clustered into three CCs, with CC5 originating from human ancestral strains through human-to-animal host transfers, making it the dominant group. Conclusions: This study provided valuable insights into regional trends, allowing for the identification of significant antibiotic-resistant patterns and offering an understanding of bacterial dynamics in these environments, underscoring the importance of routine resistance surveillance in dairy farms. Full article

Escherichia coli (E. coli) has the ability to induce clinical and subclinical mastitis in dairy cows, causing a huge loss for the dairy industry. In this study, 51 subclinical mastitis isolates and 36 clinical mastitis isolates from eight provinces of China between 2019 and 2021 were used to investigate the differences in their biological characteristics. The results showed that B1 (52.9%) and A (39.1%) were the predominant phylogroups; R1 (50.6%) was the predominant lipopolysaccharide (LPS) core type; and 44 STs (ST10 and ST58 were the most sequence-prevalent STs) and 2 new STs (ST14828 and ST14829) were identified; however, no significant difference was observed between the clinical and subclinical group strains. To compare the virulence gene differences between the clinical and subclinical mastitis-related isolates, 18 common virulence genes (including afaE, eaeA, papC, saa, sfa, ompA, aer, irp2, iucD, escV, sepD, east1, estB, stx2e, CNF1, cba, hlyA and traT) were determined using the PCR method. The results showed that the detection rates of traT, irp2 and iucD in clinical mastitis isolates were significantly higher than those in subclinical mastitis isolates (p ˂ 0.05). Meanwhile, subclinical-group E. coli had stronger biofilm formation abilities than the clinical group (p < 0.05) in 78 (89.7%) mastitis-related E. coli that could form biofilms. Furthermore, 87 mastitis-related E. coli showed severe resistance against tetracycline (37.9%), ampicillin (36.8%), streptomycin (34.5%) and cotrimoxazole (28.7%); their most prevalent resistance genes were blaCTX-M (33.3%), tetA (27.6%), sul2 (18.4%) and strB (28.7%). It was noteworthy that the clinical-group strains had a higher resistance against ampicillin and possessed higher amounts of the resistance gene blaCTX-M (p < 0.05) compared to the subclinical group. This study aims to provide references for preventing the E. coli isolates from inducing different types of mastitis. Full article

Background/Objectives: Carbapenem resistance poses a significant health threat. This study reports the first detection and characterization of a novel variant of New Delhi metallo-β-lactamase (bla_NDM-60) in Escherichia coli from the United Arab Emirates (UAE), including its genetic context and relationship to global strains. Methods: NDM-60-producing E. coli was isolated from a rectal swab during routine screening. Characterization involved whole-genome sequencing, antimicrobial susceptibility testing, and comparative genomic analysis with 66 known NDM variants. Core genome analysis was performed against 42 global E. coli strains, including the single other reported NDM-60-positive isolate. Results: The strain demonstrated extensive drug resistance, including resistance to novel β-lactam/β-lactamase inhibitor combinations, notably taniborbactam. NDM-60 differs from the closely related NDM-5 by a single amino acid substitution (Asp202Asn) and two amino acid substitutions (Val88Leu and Met154Leu) compared to NDM-1. NDM-60 is located on a nonconjugative IncX3 plasmid. The strain belongs to sequence type 940 (ST940). Phylogenetic analysis revealed high diversity among the global ST940 strains, which carry a plethora of resistance genes and originated from humans, animals, and the environment from diverse geographic locations. Conclusions: NDM-60 emergence in the UAE represents a significant evolution in carbapenemase diversity. Its presence on a nonconjugative plasmid may limit spread; however, its extensive resistance profile is concerning. Further studies are needed to determine the prevalence, dissemination, and clinical impact of NDM-60. NDM evolution underscores the ongoing challenge in managing antimicrobial resistance and the critical importance of vigilant molecular surveillance. It also highlights the pressing demand to discover new antibiotics to fight resistant bacteria. Full article

Background/Objectives: Antimicrobial resistance represents a challenge to public health systems because of the array of resistance and virulence mechanisms that lead to treatment failure and increased mortality rates. Although for years the main driver of carbapenem resistance in Italy has been the Klebsiella pneumoniae KPC carbapenemase, recent years have seen an increase in VIM and NDM metallo-beta-lactamases (MBLs). We conducted a five-year survey of New Delhi Metallo-beta-Lactamase (NDM)-producing Klebsiella pneumoniae (NDM-Kpn) clinical isolates from the Lazio region, Italy; the study aimed to elucidate the molecular mechanisms underpinning their resistant and virulent phenotype. Methods: Antimicrobial susceptibility was evaluated by automated systems and broth microdilution. In silico analysis of acquired resistance and virulence genes was performed using whole-genome sequencing (WGS), molecular typing through MLST, and core genome multi-locus sequence typing (cgMLST). Conclusions: A total of 126 clinical NDM-Kpn isolates were collected from 19 distinct hospitals in the Lazio region. Molecular analysis highlighted the existence of NDM-1 (108/126) and NDM-5 (18/126) variants, 18 Sequence Types (STs), and 15 Cluster Types (CTs). Notably, 31/126 isolates displayed a virulence score of 4, carrying ybt, ICEKp, iuc, and rmp genes. This study identified a variety of NDM-Kpn STs, mainly carrying the bla_NDM-1 gene, with a significant number linked to high-risk clones. Of these isolates, 24.6% showed high-level resistance and virulence, emphasizing the risk of the spread of strains that combine multi-drug-resistance (MDR) and virulence. Proactive surveillance and international collaborations are needed to prevent the spread of high-risk clones, as well as further research into new antimicrobial agents to fight antibiotic resistance. Full article

Background: The increase in antimicrobial resistance includes emerging mechanisms such as 16S ribosomal RNA methylases, which confer high-level resistance to aminoglycosides. In this regard, the most predominant genes observed worldwide are rmtB and armA, but their presence in Uruguay is unknown. Objectives: We describe the genomic characterization of isolates carrying rmtB and rmtC, together with bla_NDM-5 and bla_NDM-1, respectively, and rmtD in our country. Methology: Five isolates from patients admitted to three hospitals were studied. Identification and antibiotic susceptibility testing were performed using the Vitek2 System. Whole Genome Sequencing was conducted, and hybrid assembly was performed with Unicycler. In silico analysis using the Center for Genomic Epidemiology’s tools was undertaken to predict antibiotic resistance determinants, plasmid incompatibility groups, and sequence types. Results: We report three K. pneumoniae ST307 isolates with an IncR plasmid carrying bla_NDM-5/bla_CTX-M-15/bla_TEM-1B/rmtB/dfrA14/dfrA12/sul1/qacEΔ1/ermB/mphA, one K. pneumoniae ST258 harboring an IncC plasmid containing rmtC/bla_NDM-1/bla_CMY-6/aac(6′)-Ib/sul1, and one E. cloacae ST88 isolate with an IncFIB/II plasmid hosting rmtD, within a novel Tn21-like transposon named Tn7825, alongside bla_OXA-101/sul1/tet(G)/floR, and a new variant of bla_TEM assigned as bla_TEM-258. One of the strains, named UH_B2, also carried an IncM1 plasmid encoding qnrE1/bla_TEM-1/bla_CTX-M-8 associated with ISEcp1. Conclusions: This is the first description of plasmids harboring 16S rRNA methyltransferases in Uruguay. The association and dissemination of diverse antibiotic-resistant genes underpin the health threat they represent, highlighting the lack of available antibiotics effective against multidrug-resistant microorganisms. Full article

Bacillus cereus sensu lato can contaminate food and cause food poisoning by producing toxins such as cereulide, toxin BL, and cytotoxin K. In this study, we retrospectively analyzed B. cereus sensu lato from retail food products and food poisoning cases using PCR methods to determine their virulence profiles. A new toxin profile, encoding all four toxins (hbl, nhe, cytK, ces), was found in 0.4% of isolates. The toxin profiles, classified into A-J, revealed that 91.8% harbored nhe genes, while hbl, cytK, and ces were detected in 43.8%, 46.9%, and 4.2% of isolates, respectively. Whole-genome sequencing (WGS) identified four distinct species within the B. cereus group, with 21 isolates closely related to B. cereus sensu stricte, 25 to B. mosaicus, 2 to B. toyonensis, and 1 to B. mycoides. Three novel sequence types (STs 3297, 3298, 3299) were discovered. Antibiotic resistance genes were common, with 100% of isolates carrying beta-lactam resistance genes. Fosfomycin (80%), vancomycin (8%), streptothricin (6%), tetracycline (4%), and macrolide resistance (2%) genes were also detected. These results highlight the genetic diversity and antibiotic resistance potential of B. cereus sensu lato strains in Polish food products. Full article