Resistance phenotype and virulence potential of Leclercia adecarboxylata strains isolated from different sources.

Introduction. Leclercia adecarboxylata is a member of Enterobacterales, often considered an opportunistic pathogen. Recent reports have highlighted L. adecarboxylata as an emerging pathogen harbouring virulence and resistance determinants.Gap statement. Little information exists on virulence and resistance determinants in L. adecarboxylata strains isolated from environmental, food, and clinical samples.Aim. To determine the presence of resistance and virulence determinants and plasmid features in L. adecarboxylata strains isolated from environmental, food, and clinical samples, as well as their phylogenetic relationship.Results. All strains tested showed resistance to ß-lactams and quinolones but were sensitive to aminoglycosides and nitrofurans. However, even though fosfomycin resistance is considered a characteristic trait of L. adecarboxylata, the resistance phenotype was only observed in 50 % of the strains; bla TEM was the most prevalent BLEE gene (70 %), while the quinolone qnrB gene was observed in 60 % of the strains. Virulence genes were differentially observed in the strains, with adhesion-related genes being the most abundant, followed by toxin genes. Finally, all strains carried one to seven plasmid bands ranging from 7 to 125 kbps and harboured several plasmid addiction systems, such as ParDE, VagCD, and CcdAB in 80 % of the strains.Conclusions. L. adecarboxylata is an important emerging pathogen that may harbour resistance and virulence genes. Additionally, it has mobilizable genetic elements that may contribute to the dissemination of genetic determinants to other bacterial genera.

Isolation, in vitro, and in vivo pathogenicity test of Tilapia lake virus (TiLV) and development of a prognostic semi-quantitative lesion scoring system for differentiating clinical/subclinical infection in farmed tilapia (Oreochromis niloticus L.).

Tilapia lake virus ('TiLV-MH-2022') was recently recovered from the naturally infected farmed tilapia. Reverse transcription-polymerase chain reaction (RT-PCR) using segment 1 specific primers, followed by Sanger sequencing, confirmed the infection. The pairwise sequence homology of segment 1 showed its close relationship with the previous isolates. The virus was successfully detected from the mucus, which emphasised the possibility of non-invasive screening of tilapia on a large scale. The virus inoculum prepared from the infected tissues was tested for in vivo and in vitro pathogenicity. Around 100-140 nm-sized electron-dense virus particles were observed in the infected OnlL cells. Based on the onset of symptoms and lesions, all RT-PCR-positive fish were categorised into two groups, 'clinical' and 'subclinical'. A lesion-scoring technique was developed for assessing the pathogenicity of the virus isolate. The external and internal gross lesions and histopathological alterations in the critical organs of the fish, such as the brain, kidney, gills, and liver, were assessed on a scale of 0 (no gross lesion) to 5 (most severe lesions). Overall lesion score was significantly high in the clinical and subclinical groups for gross and histopathology, respectively. This study is the first such attempt to standardise a semi-quantitative lesion scoring technique for TiLV infection, which establishes a clinical relevance and prognostic ability to distinguish between the apparent and inapparent infection.

The emergence of multidrug-resistant Proteus vulgaris infection in cage reared Pangasianodon hypophthalmus: Molecular characterization and host-pathogen response.

The study investigates the causative agent responsible for massive mortality in Pangasianodon hypophthalmus cage farms. The infected pangasius were lethargic, not taking feed, and had exophthalmia, deep ulceration, and hemorrhage on the ventral body surface. Pathogens were isolated from infected pangasius tissue samples, and the strain was preliminarily identified as Proteus vulgaris based on morphology, biochemical tests, 16S rRNA PCR sequencing, and phylogenetic analysis. The microbiological analysis revealed that P. vulgaris was associated with the disease outbreak and mortality of P. hypophthalmus, as confirmed by the biofilm formation, swimming activity, and survival assay results. The isolated P. vulgaris was resistant to several antibiotics, including Doxycycline, Dicloxacillin, Polymyxin B, Chloramphenicol, and Imipenem, exhibiting multiple antibiotic-resistant phenotypes. Furthermore, a host-pathogen model was developed to investigate the in vivo effect of emerging P. vulgaris infection in striped catfish. Results showed that P. vulgaris infection exhibited varying degrees of cellular changes in the kidney, liver, and gill tissues of infected P. hypophthalmus samples. The transcription analysis further highlights that P. vulgaris modulates the antioxidants, immune activation, growth regulator, homeostasis, degradation of invading DNA, and DNA damage-related gene expression in liver, kidney, spleen, skin, and gill tissue samples of infected P. hypophthalmus. The lessons learned from the study could be critical in understanding the P. vulgaris infection patterns and pathobiology necessary to enable risk assessment and develop management measures to control the bacterium's virulence.

Characterization of a colistin resistant, hypervirulent hospital isolate of Acinetobacter courvalinii from Canada.

Non-baumannii Acinetobacter spp. are becoming more prevalent in clinical settings including those that present resistance to last-resort antibiotics such as colistin. AB222-IK40 is an Acinetobacter courvalinii strain isolated from the Ottawa Hospital Research Institute located in Ottawa, Canada. To our knowledge, it is the first report of clinical A. courvalinii in Canada. Based on the susceptibility profile, AB222-IK40 is resistant to colistin and non-susceptible to ertapenem. Whole-genome sequencing allowed for genomic investigation into colistin resistance mechanisms. No previously identified mechanism(s) were observed, but a mobile colistin resistance (mcr)-like gene and a UDP-glucose dehydrogenase gene were identified. Based on phylogenomic analyses, the mcr-like gene is an intrinsic phosphoethanolamine transferase. This gene family is implicated in one of the many mechanisms responsible for colistin resistance in Acinetobacter baumannii as well as Acinetobacter modestus. UDP-glucose dehydrogenase is involved in colistin resistance in Enterobacterales and has been shown to be involved in capsule formation in A. baumannii. Global lipidomics revealed greater abundance of phosphatidyl-myo-inositol and lyso-phosphatidyl ethanolamine moieties in the membrane of A. courvalinii than in A. baumannii. Lipidomic profiles showed differences that were probably responsible for the colistin resistance phenotype in AB222-IK40. This isolate was also hypervirulent based on survival assays in Galleria mellonella. As this is the first report of A. courvalinii from a hospital in Canada, this species may be an emerging clinical pathogen, and therefore, it is important to understand this mechanism of its colistin resistance and hypervirulence.

Emergence of Salmonella Infantis carrying the pESI-like plasmid from eggs in egg grading and packing plants in Korea.

The plasmid of emerging S. Infantis (pESI) or pESI-like plasmid in Salmonella enterica Infantis are consistently reported in poultry and humans worldwide. However, there has been limited research on these plasmids of S. Infantis isolated from eggs. Therefore, this study aimed to analyze the prevalence and characteristics of S. Infantis carrying the pESI-like plasmid from eggs in egg grading and packing plants. In this study, the pESI-like plasmid was only detected in 18 (78.3%) of 23 S. Infantis isolates, and it was absent in the other 9 Salmonella serovars. In particular, S. Infantis isolates carrying the pESI-like plasmid showed the significantly higher resistance to ß-lactams, phenicols, cephams, aminoglycosides, quinolones, sulfonamides, and tetracyclines than Salmonella isolates without the pESI-like plasmid (p < 0.05). Moreover, all S. Infantis isolates carrying the pESI-like plasmid were identified as extended-spectrum ß-lactamase (ESBL) producer, harboring the blaCTX-M-65 and blaTEM-1 genes, and carried non-ß-lactamase resistance genes (ant(3'')-Ia, aph(4)-Ia, aac(3)-IVa, aph(3')-Ic, sul1, tetA, dfrA14, and floR) against five antimicrobial classes. However, all isolates without the pESI-like plasmid only carried the blaTEM-1 gene among the ß-lactamase genes, and either had no non-ß-lactamase resistance genes or harbored non-ß-lactamase resistance genes against one or two antimicrobial classes. Furthermore, all S. Infantis isolates carrying the pESI-like plasmid carried class 1 and 2 integrons and the aadA1 gene cassette, but none of the other isolates without the pESI-like plasmid harbored integrons. In particular, D87Y substitution in the gyrA gene and IncP replicon type were observed in all the S. Infantis isolates carrying the pESI-like plasmid but not in the S. Infantis isolates without the pESI-like plasmid. The distribution of pulsotypes between pESI-positive and pESI-negative S. Infantis isolates was clearly distinguished, but all S. Infantis isolates were classified as sequence type 32, regardless of whether they carried the pESI-like plasmid. This study is the first to report the characteristics of S. Infantis carrying the pESI-like plasmid isolated from eggs and can provide valuable information for formulating strategies to control the spread of Salmonella in the egg industry worldwide.

Francisella salimarina infection in farmed cobia (Rachycentron canadum) and dusky grouper (Epinephelus marginatus) in Brazil: A case report.

This study aimed to identify and characterize isolates of Francisella salimarina associated with an outbreak on a marine fish farm in Brazil and to analyse their genetic variability and antimicrobial susceptibility. In 2021, diseased cobias (Rachycentron canadum, n = 10) and dusky groupers (Epinephelus marginatus, n = 10) were sampled and subjected to bacteriological and pathological examinations. The isolates obtained were morphologically and biochemically characterized and identified by matrix-assisted laser desorption/ionization-time of flight (MALDI-ToF) and 16S rRNA gene sequencing. The genetic diversity of these isolates was analysed using repetitive extragenic palindromic-polymerase chain reaction (REP-PCR). Antimicrobial susceptibility was assessed using the disk diffusion technique. Macroscopically, the fish presented skin ulcerations, ocular lesions, hepatomegaly and splenomegaly. A pleomorphic, gram-negative, catalase- and oxidase-positive bacterium was isolated from seven cobias and two groupers. The 16S rRNA gene sequences showed >99% coverage and identity with other deposited sequences of F. salimarina. The results of the biochemical analysis corresponded to these bacterial species. Histologically, granulomas were observed in the spleen, liver and heart of the cobias (n = 6), and necrotizing and fibrinous dermatitis and myositis were identified in some groupers (n = 2). The isolates exhibited the same banding pattern when REP-PCR was performed, indicating that they were clonally related. Finally, the antibiogram test, no inhibition halo was observed for amoxicillin and trimethoprim-sulfamethoxazole. To our knowledge, this is the first report of F. salimarina infection in cobias and dusky groupers.

Host Range Characterization of Phytophthora sansomeana Across Corn, Soybean, Wheat, Winter Cereal Rye, Dry Bean, and Oats and an In Vitro Assessment of Seed Treatment Sensitivity.

Formally described in 2009, Phytophthora sansomeana is a pathogen of increasing interest in native, agricultural, and horticulturally important plant species. The objective of this study was to elucidate the symptomatic and asymptomatic host range of P. sansomeana on six agricultural crop species commonly used in field crop rotations in Michigan. In addition, sensitivity to oomicides commonly used in seed treatments, including oxathiapiprolin, mefenoxam, ethaboxam, and pyraclostrobin, was performed to aid in disease management recommendations. Plant biomass, quantity of P. sansomeana DNA in roots, and reisolations were used to assess pathogenicity and virulence of 18 isolates of P. sansomeana on each plant species using an inoculated seedling growth chamber assay. Isolates displayed varying levels of virulence to the hosts tested. Reisolations were completed for each plant species tested, and varying quantities of P. sansomeana DNA were found within all plant species root samples. Corn, wheat, soybean, dry bean, and winter cereal rye plants were symptomatic hosts with significant reduction observed in the total plant biomass. No significant reduction in total plant biomass was observed in oats, and oat roots harbored the least amount of P. sansomeana DNA. No P. sansomeana isolates were insensitive to the oomicide compounds tested with mean absolute inhibition (EC50) values of fungicide required for 50% growth inhibition values of 7.8 × 10-2 µg/ml for mefenoxam, 1.13 × 10-1 µg/ml for ethaboxam, 2.6 × 10-2 µg/ml for oxathiapiprolin, and 3.04 × 10-1 µg/ml for pyraclostrobin. These results suggest that common crop rotations in Michigan may not be a viable option to reduce soilborne inoculum accumulation and oomicide seed treatments could be considered for early-season management of P. sansomeana.

First Report of Bacterial Leaf Spot Disease on Sesame (Sesamum indicum L.) Caused by Pseudomonas syringae pv. sesami in North Carolina.

In July 2022, dark brown to black, angular, water-soaked lesions were observed on sesame leaves (Sesamum indicum L.) in a research plot established to assess yield potential for eight varieties at the North Carolina (NC) Sandhills Research Station (Chavez 2023). Symptoms were indicative of a bacterial leaf spot (BLS). At early flowering stage, leaf spots were present on scattered plants; varieties ES108, SS3301, and ES201 exhibited up to 75% disease prevalence, with lower frequency in ES103, S39, S4302, S3251, and S3276. Symptomatic leaves from 3-4 plants were collected on four different dates from July through September. A section of symptomatic tissue was excised and macerated in sterile deionized water (SDW). A 10 µL aliquot was streaked onto SPA medium (15 g sucrose, 5.0 g proteose peptone, 0.50 g MgSO4 7H2O, 0.25 g K2HPO4, 15 g agar per liter of SDW) and incubated at 28ºC. After 72 h, numerous, smooth, white-cream colored, convex-shaped, colonies were individually isolated. Five randomly selected isolates from the different collection dates, designated as AHP108-AHP111 and AHP116, were genotyped. The 16S rRNA, gyrB, rpoD, and gapA genes were sequenced (Heuer et al. 1997; Hwang et al. 2005) and deposited to NCBI (GenBank Accessions: P213467- PP213470; OQ628040-OQ628042; PP214983-PP214994; and PP255798). These five isolates shared 100% sequence identity for gyrB and rpoD. AHP108-AHP111 shared 100% sequence identity for 16S rRNA and gapA, with 99.7% and 90.8% identity, respectively, for AHP116. A phylogenetic tree was inferred from a maximum-likelihood analysis of concatenated gyrB, rpoD, and gapA sequences of the five isolates and the top 11 hts from a blastn search of the NCBI nucleotide database. Those hits included closely related sequences from Pseudomonas syringae pv. sesami type strains ICMP 763T and ICMP 7459T. Based on this phylogenetic analysis AHP108-AHP111 and AHP116 are P. syringae pv. sesami. Recent genomic analysis suggests this pathovar is part of P. amygdali (Gomila et al. 2017), but an official name change has not been proposed. Each of the five isolates were infiltrated into leaves of sesame varieties ES108, ES103, and S327, consistently resulting in similar symptoms. Thus, strain AHP116, as a representative, was used to fulfill Koch's postulates using five, 30-day-old potted sesame plants (var. S3301). Plants were spray-inoculated with a bacterial suspension of ~108 CFU/ml until runoff; plants were incubated in moist chambers 24 h pre and post inoculation at 28ºC with 80% relative humidity and a 12 h photoperiod. At 13 days post inoculation, symptoms resembling those on plants at the Sandhills Research Stations in 2022 were evident. Reisolated bacteria were confirmed to be AHP116 through 16S rRNA and gyrB amplification and sequencing. No symptoms were observed on the five water-inoculated plants. BLS of sesame has been reported in Asia and is thought to be seedborne (Firdous et al. 2009; Prathuangwong and Yowabutra 1997). To our knowledge, this is the first report of P. syringae pv. sesami causing BLS on sesame in North Carolina. Sesame cultivation in the state increased from approximately 2,000 acres in 2022 to 13,000 acres in 2023 and there is interest in cultivating sesame as a rotational and alternative crop because it requires minimal input costs. Potential outbreaks of BLS in this warm, humid region could negatively affect sesame production, where little is known about the economic impact of the disease.

First case of Chryseobacterium gallinarum bloodstream infection: a diagnostic and therapeutic challenge for an emerging pathogen.

Chryseobacterium spp. belongs to the Flavobacteriaceae family and is a rod-shaped gram-negative, glucose non-fermenting, non-motile bacterium ubiquitous in the environment. In humans, Chryseobacterium may be responsible for infections such as urinary tract infections (UTI) and ventriculitis with a pathogenic burden increasing in recent years. Chryseobacterium gallinarum was isolated for the first time in 2014 in a pharyngeal scrape sample of chicken and, until now, only one case of human UTI has been described in a pregnant 20-year-old Indian patient. Herein, we report the first case of bloodstream infection caused by C. gallinarum in a 67-year-old female burn patient, correctly identified by 16S-rRNA sequencing and successfully treated with cefepime and fosfomycin.

Unveiling Trichosporon austroamericanum sp. nov.: A Novel Emerging Opportunistic Basidiomycetous Yeast Species.

During an epidemiological survey, a potential novel species within the basidiomycetous yeast genus Trichosporon was observed. The clinical strain was obtained from a urine sample taken from a Brazilian kidney transplant recipient. The strain was molecularly identified using the intergenic spacer (IGS1) ribosomal DNA locus and a subsequent phylogenetic analysis showed that multiple strains that were previously reported by other studies shared an identical IGS1-genotype most closely related to that of Trichosporon inkin. However, none of these studies provided an in-depth characterization of the involved strains to describe it as a new taxon. Here, we present the novel clinically relevant yeast for which we propose the name Trichosporon austroamericanum sp. nov. (holotype CBS H-24937). T. austroamericanum can be distinguished from other siblings in the genus Trichosporon using morphological, physiological, and phylogenetic characters.

First Isolation of the Heteropathotype Shiga Toxin-Producing and Extra-Intestinal Pathogenic (STEC-ExPEC) E. coli O80:H2 in French Healthy Cattle: Genomic Characterization and Phylogenetic Position.

The emerging heteropathotype shigatoxigenic (STEC) and extra-intestinal pathogenic Escherichia coli (ExPEC) O80:H2 has been the second leading cause of pediatric HUS in France since the mid-2010s. In contrast with other highly pathogenic STEC serotypes, for which ruminants have clearly been identified as the main human infection source, this heteropathotype's reservoir remains unknown. In this context, we describe for the first time the isolation of seven STEC O80:H2 strains from healthy cattle on a single cattle farm in France. This study aimed at (i) characterizing the genome and (ii) investigating the phylogenetic positions of these O80:H2 STEC strains. The virulomes, resistomes, and phylogenetic positions of the seven bovine isolates were investigated using in silico typing tools, antimicrobial susceptibility testing and cgMLST analysis after short-read whole genome sequencing (WGS). One representative isolate (A13P112V1) was also subjected to long-read sequencing. The seven isolates possessed ExPEC-related virulence genes on a pR444_A-like mosaic plasmid, previously described in strain RDEx444 and known to confer multi-drug resistance. All isolates were clonally related and clustered with human clinical strains from France and Switzerland with a range of locus differences of only one to five. In conclusion, our findings suggest that healthy cattle in France could potentially act as a reservoir of the STEC-ExPEC O80:H2 pathotype.

Epidemiological trends and clinical features of the ongoing monkeypox epidemic: A preliminary pooled data analysis and literature review.

An emerging outbreak of monkeypox infection is quickly spreading worldwide, being currently reported in more than 30 countries, with slightly less than 1000 cases. In the present preliminary report, we collected and synthesized early data concerning epidemiological trends and clinical features of the ongoing outbreak and we compared them with those of previous outbreaks. Data were pooled from six clusters in Italy, Australia, the Czech Republic, Portugal, and the United Kingdom, totaling 124 cases (for 35 of which it was possible to retrieve detailed information). The ongoing epidemic differs from previous outbreaks in terms of age (54.29% of individuals in their thirties), sex/gender (most cases being males), risk factors, and transmission route, with sexual transmission being highly likely. Also, the clinical presentation is atypical and unusual, being characterized by anogenital lesions and rashes that relatively spare the face and extremities. The most prevalent sign/symptom reported was fever (in 54.29% of cases) followed by inguinal lymphadenopathy (45.71%) and exanthema (40.00%). Asthenia, fatigue, and headache were described in 22.86% and 25.71% of the subjects, respectively. Myalgia was present in 17.14% of the cases. Both genital and anal lesions (ulcers and vesicles) were reported in 31.43% of the cases. Finally, cervical lymphadenopathy was described in 11.43% of the sample, while the least commonly reported symptoms were diarrhea and axillary lymphadenopathy (5.71% of the case series for both symptoms). Some preliminary risk factors can be identified (being a young male, having sex with other men, engaging in risky behaviors and activities, including condomless sex, human immunodeficiency virus positivity (54.29% of the sample analyzed), and a story of previous sexually transmitted infections, including syphilis). On the other hand, being fully virally suppressed and undetectable may protect against a more severe infectious course. However, further research in the field is urgently needed.

Rapid and reliable inactivation protocols for the diagnostics of emerging viruses: The example of SARS-CoV-2 and monkeypox virus.

The emergence and sustained transmission of novel pathogens are exerting an increasing demand on the diagnostics sector worldwide, as seen with the ongoing severe acute respiratory coronavirus 2 (SARS-CoV-2) pandemic and the more recent public health concern of monkeypox virus (MPXV) since May 2022. Appropriate and reliable viral inactivation measures are needed to ensure the safety of personnel handling these infectious samples. In the present study, seven commercialized diagnosis buffers, heat (56°C and 60°C), and sodium dodecyl sulfate detergent (2.0%, 1.0%, and 0.5% final concentrations) were tested against infectious SARS-CoV-2 and MPXV culture isolates on Vero cell culture. Cytopathic effects were observed up to 7 days postinoculation and viral load evolution was measured by semiquantitative polymerase chain reaction. The World Health Organization recommends an infectious titer reduction of at least 4 log10 . As such, the data show efficacious SARS-CoV-2 inactivation by all investigated methods, with >6.0 log10 reduction. MPXV inactivation was also validated with all investigated methods with 6.9 log10 reductions, although some commercial buffers required a longer incubation period to yield complete inactivation. These results are valuable for facilities, notably those without biosafety level-3 capabilities, that need to implement rapid and reliable protocols common against both SARS-CoV-2 and MPXV.

The high diversity of Scedosporium and Lomentospora species and their prevalence in human-disturbed areas in Taiwan.

Scedosporium and Lomentospora are important opportunistic pathogens causing localized or disseminated infection in humans. Understanding their environmental distribution is critical for public hygiene and clinical management. We carried out the first environmental survey in urbanized and natural regions in Taiwan. Overall, Scedosporium and Lomentospora species were recovered in 132 out of 273 soil samples (48.4%) across Taiwan. We morphologically and molecularly identified six Scedosporium and one Lomentospora species. All four major clinical relevant species were isolated with high frequency, i.e., Scedosporium apiospermum (42.4%), S. boydii (21.8%), Lomentosporaprolificans (14.5%), S. aurantiacum (8.5%); two clinically minor species, Pseudallescheria angusta (6.7%) and S. dehoogii (5.6%), and a saprobic species, S. haikouense (0.6%), had moderate to rare incidence. These fungal species had high incidence in urban (48.6%) and hospital (67.4%) soil samples, and had limited distribution in samples from natural regions (5%). Multivariate analysis of the fungal composition revealed strong evidence of the preferential distribution of these fungi in urban and hospital regions compared with natural sites. In addition, strong evidence suggested that the distribution and abundance of these fungal species were highly heterogeneous in the environment; samples in vicinity often yielded varied fungal communities. We concluded that these fungal species were prevalent in soil in Taiwan and their occurrences were associated with human activities. Although, hygiene sensitive sites such as hospitals were not harboring heavier fungal burdens than other urban facilities in our survey, still, aware should be taken for the high frequency of these clinical relevant species around hospital regions.

Scedosporium and Lomentospora are two fungal genera that can cause infections to wildlife and humans. Our experiment demonstrated that these fungi are ubiquitous in the soil in Taiwan. Their proximity to human-dwelling regions raises our awareness of their exposure to those who are susceptible.

Candida khanbhai sp. nov., a new clinically relevant yeast within the Candida haemulonii species complex.

Invasive fungal infections caused by non-albicans Candida species are increasingly reported. Recent advances in diagnostic and molecular tools enabled better identification and detection of emerging pathogenic yeasts. The Candida haemulonii species complex accommodates several rare and recently described pathogenic species, C. duobushaemulonii, C. pseudohaemulonii, C. vulturna, and the most notorious example is the outbreak-causing multi-drug resistant member C. auris. Here, we describe a new clinically relevant yeast isolated from geographically distinct regions, representing the proposed novel species C. khanbhai, a member of the C. haemulonii species complex. Moreover, several members of the C. haemulonii species complex were observed to be invalidly described, including the clinically relevant species C. auris and C. vulturna. Hence, the opportunity was taken to correct this here, formally validating the names of C. auris, C. chanthaburiensis, C. konsanensis, C. metrosideri, C. ohialehuae, and C. vulturna.

Although C. albicans remains the major pathogenic yeast, other previously rare or even novel species are on the rise in the clinic. The most notorious example is the rapid global emergence of multidrug-resistant C. auris. Here we describe its novel sibling species C. khanbhai.

Kingella pumchi sp. nov., an organism isolated from human vertebral puncture tissue.

A Gram-negative, non-motile rod and strictly aerobic bacterium, designated as 18B16333T, was isolated from vertebral puncture tissue of a patient at Peking union medical college hospital in China. Growth occurred in NaCl concentrations of 0-1% (w/v) (optimum growth at 0% NaCl), at temperatures of 25-40 °C (optimum growth at 37 °C) and at pH 6.0-9.0 (optimum growth at pH 8.0). Diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine were the predominant polar lipids, and the major fatty acids were C16:0, C18:1 ω7c/C18:1 ω6c and C16:1 ω7c/C16:1 ω6c. Phylogenetic analysis based on 16S rRNA gene sequence comparisons indicated that strain 18B16333T was most closely related to Kingella potus CCUG 49773 T (97.3%, 16S rRNA gene sequence identity) and Neisseria bacilliformis CCUG 50858 T (96.8%). The ANI values between strain 18B16333T and the type strains K. potus CCUG 49773 T, N. bacilliformis CCUG 50858 T, Kingella kingae CCUG 352 T and Neisseria gonorrhoeae CCUG 26876 T were 77.3%, 79.1%, 72.1% and 75.4%, respectively. The dDDH values between strain 18B16333T and the four reference strains mentioned above were 24.8%, 26.9%, 24.2% and 20.7%. Further core gene analysis distinctively clustered strain 18B16333T with four Kingella species but not with Neisseria species. Based on the phenotypic, chemotaxonomic, and phylogenetic properties, strain 18B16333T represents a novel species of the genus Kingella, for which the name Kingella pumchi sp. nov. is proposed. The type strain is Kingella pumchi 18B16333T (= CICC 24913 T = CCUG 75125 T).

Ophidiomycosis is associated with alterations in the acute glycemic and glucocorticoid stress response in a free-living snake species.

Emerging fungal pathogens are a direct threat to vertebrate biodiversity. Elucidating the mechanisms by which mycoses impact host fitness is an important step towards effective prediction and management of disease outcomes in populations. The vertebrate acute stress response is an adaptive mechanism that allows individuals to meet challenges to homeostasis and survival in dynamic environments. Disease may cause stress, and coping with fungal infections may require shifts in resource allocation that alter the ability of hosts to mount an acute response to other external stressors. We examined the glucocorticoid and glycemic response to acute capture stress in a population of free-living pygmy rattlesnakes, Sistrurus miliarius, afflicted with an emerging mycosis (ophidiomycosis) across seasons. In all combinations of disease status and season, acute capture stress resulted in a significant glucocorticoid and glycemic response. While disease was not associated with elevated baseline or stress-induced corticosterone (CORT), disease was associated with an increased glucocorticoid stress response (post-stress minus baseline) across seasons. Both baseline and stress-induced glucose were lower in snakes with ophidiomycosis compared to uninfected snakes. The relationship between glucose and pre- and post-stress CORT depended on infection status, and positive correlations were only observed in uninfected snakes. The variables which explained CORT and glucose levels were different. The pattern of CORT was highly seasonal (winter high - summer low) and negatively related to body condition. Glucose, on the other hand, did not vary seasonally or with body condition and was strongly related to sex (male high - female low). Our results highlight the fact that circulating CORT and glucose are sensitive to different intrinsic and extrinsic predictor variables and support the hypothesis that disease alters the acute physiological stress response. Whether the effects of ophidiomycosis on the acute stress response result in sublethal effects on fitness should be investigated in future studies.

A first case of prosthetic joint infection with Actinomyces radingae.

Prosthetic joint infection is a common clinical orthopedic problem but infections caused by Actinomyces species have been rarely reported. An increasing number of reports identifying Actinomyces in cases of prosthetic joint infection suggest it may be an emerging pathogen. We describe here the first known case of a prosthetic joint infection caused by Actinomyces radingae.

First isolation of Carnobacterium maltaromaticum from farmed Rainbow Trout in Virginia.

OBJECTIVE: Carnobacterium maltaromaticum is considered an emerging pathogen of salmonids in the United States and around the world. METHODS: Bacterial cultures obtained from the posterior kidney and skin of moribund Rainbow Trout Oncorhynchus mykiss from a commercial aquaculture facility in Virginia, USA, grew C. maltaromaticum, which was confirmed by additional phenotypic and molecular characterization. RESULT: A presumptive diagnosis based on the clinical signs, necropsy observations, histopathology, and bacterial cultures was bacterial septicemia due to C. maltaromaticum. CONCLUSION: This represents the first documentation of C. maltaromaticum in Rainbow Trout from Virginia.

Enteroinvasive Escherichia coli O96:H19 is an Emergent Biofilm-Forming Pathogen.

Enteroinvasive Escherichia coli (EIEC) is a diarrheagenic E. coli pathotype carrying a virulence plasmid that encodes a type III secretion system (TTSS) directly implicated in bacterial cell invasion. Since 2012, EIEC serotype O96:H19 has been recognized in Europe, Colombia, and most recently Uruguay. In addition to the invasion phenotype, the strains isolated from Colombian children with moderate-to-severe gastroenteritis had a strong biofilm formation phenotype, and as a result, they are referred to as biofilm-forming enteroinvasive E. coli (BF-EIEC). The objective of this study was to characterize the biofilm formation phenotype of the BF-EIEC O96:H19 strain 52.1 isolated from a child with moderate-to-severe gastroenteritis in Colombia. Random mutagenesis using Tn5 transposons identified 100 mutants unable to form biofilm; 20 of those had mutations within the pgaABCD operon. Site-directed mutagenesis of pgaB and pgaC confirmed the importance of these genes in N-acetylglucosamine-mediated biofilm formation. Both biofilm formation and TTSS-mediated host cell invasion were associated with host cell damage on the basis of cytotoxic assays comparing the wild type, invasion gene mutants, and biofilm formation mutants. Multilocus sequence typing-based phylogenetic analysis showed that BF-EIEC strain 52.1 does not cluster with classic EIEC serotype strains. Instead, BF-EIEC strain 52.1 clusters with EIEC serotype O96:H19 strains described in Europe and Uruguay. In conclusion, BF-EIEC O96:H19, an emerging pathogen associated with moderate-to-severe acute gastroenteritis in children under 5 years of age in Colombia, invades cells and has a strong biofilm formation capability. Both phenotypes are independently associated with in vitro cell cytotoxicity, and they may explain, at least in part, the higher disease severity reported in Europe and Latin America. IMPORTANCE Enteroinvasive Escherichia coli (EIEC), a close relative of Shigella, is implicated in dysenteric diarrhea. EIEC pathogenicity involves cell invasion mediated by effector proteins delivered by a type III secretion system (TTSS) that disrupt the cell cytoskeleton. These proteins and the VirF global regulator are encoded by a large (>200 kb) invasion plasmid (pINV). This study reports an emergent EIEC possessing a cell invasion phenotype and a strong polysaccharide matrix-mediated biofilm formation phenotype. Both phenotypes contribute to host cell cytotoxicity in vitro and may contribute to the severe disease reported among children and adults in Europe and Latin America.