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1.
Emerg Infect Dis ; 30(3): 608-610, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38407252

RESUMEN

We describe a case of endocarditis caused by Streptobacillus moniliformis bacteria, a known cause of rat-bite fever, in a 32-year-old woman with pet rats in Germany. The patient had a strong serologic response, with high IgM and IgG titers. Serologic analysis is a promising tool to identify S. moniliformis bacterial infection.


Asunto(s)
Endocarditis , Streptobacillus , Femenino , Humanos , Animales , Ratas , Adulto , Inmunoglobulina G , Inmunoglobulina M
2.
PLoS Genet ; 17(11): e1009911, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34780474

RESUMEN

The capacity of a cell to maintain proteostasis progressively declines during aging. Virtually all age-associated neurodegenerative disorders associated with aggregation of neurotoxic proteins are linked to defects in the cellular proteostasis network, including insufficient lysosomal hydrolysis. Here, we report that proteotoxicity in yeast and Drosophila models for Parkinson's disease can be prevented by increasing the bioavailability of Ca2+, which adjusts intracellular Ca2+ handling and boosts lysosomal proteolysis. Heterologous expression of human α-synuclein (αSyn), a protein critically linked to Parkinson's disease, selectively increases total cellular Ca2+ content, while the levels of manganese and iron remain unchanged. Disrupted Ca2+ homeostasis results in inhibition of the lysosomal protease cathepsin D and triggers premature cellular and organismal death. External administration of Ca2+ reduces αSyn oligomerization, stimulates cathepsin D activity and in consequence restores survival, which critically depends on the Ca2+/calmodulin-dependent phosphatase calcineurin. In flies, increasing the availability of Ca2+ discloses a neuroprotective role of αSyn upon manganese overload. In sum, we establish a molecular interplay between cathepsin D and calcineurin that can be activated by Ca2+ administration to counteract αSyn proteotoxicity.


Asunto(s)
Calcineurina/genética , Catepsina D/genética , Enfermedad de Parkinson/genética , alfa-Sinucleína/genética , Envejecimiento/efectos de los fármacos , Envejecimiento/genética , Animales , Animales Modificados Genéticamente/genética , Calcio/metabolismo , Calcio/farmacología , Muerte Celular/genética , Drosophila melanogaster/genética , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Lisosomas/efectos de los fármacos , Lisosomas/genética , Neuronas/efectos de los fármacos , Enfermedad de Parkinson/metabolismo , Enfermedad de Parkinson/patología , Agregación Patológica de Proteínas/tratamiento farmacológico , Agregación Patológica de Proteínas/genética , Agregación Patológica de Proteínas/patología , Proteolisis/efectos de los fármacos , Saccharomyces cerevisiae/genética
3.
Parasitol Res ; 123(2): 120, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38300369

RESUMEN

We report the finding of five nymphs and three adult ticks attached to German tourists while traveling the American continents. All eight specimens were morphologically identified and confirmed genetically using the 16S rRNA gene and screened for Rickettsia spp. infections. Five tick species were identified: one Amblyomma mixtum nymph from Ecuador, one Amblyomma varium nymph from Colombia, three Amblyomma coelebs nymphs from Costa Rica, one Amblyomma americanum male from the USA, one Dermacentor andersoni female and one D. andersoni male from Canada. Tick-borne microorganisms screening using the pan-Rickettsia-PCR resulted in two positive and six negative ticks. The A. mixtum nymph was positive for Rickettsia amblyommatis, while the D. andersoni female was positive for Rickettsia peacockii.


Asunto(s)
Garrapatas , Animales , Femenino , Humanos , Masculino , Amblyomma , Ninfa , ARN Ribosómico 16S/genética , Garrapatas/clasificación
4.
Circulation ; 145(25): 1853-1866, 2022 06 21.
Artículo en Inglés | MEDLINE | ID: mdl-35616058

RESUMEN

BACKGROUND: The insulin-like growth factor 1 (IGF1) pathway is a key regulator of cellular metabolism and aging. Although its inhibition promotes longevity across species, the effect of attenuated IGF1 signaling on cardiac aging remains controversial. METHODS: We performed a lifelong study to assess cardiac health and lifespan in 2 cardiomyocyte-specific transgenic mouse models with enhanced versus reduced IGF1 receptor (IGF1R) signaling. Male mice with human IGF1R overexpression or dominant negative phosphoinositide 3-kinase mutation were examined at different life stages by echocardiography, invasive hemodynamics, and treadmill coupled to indirect calorimetry. In vitro assays included cardiac histology, mitochondrial respiration, ATP synthesis, autophagic flux, and targeted metabolome profiling, and immunoblots of key IGF1R downstream targets in mouse and human explanted failing and nonfailing hearts, as well. RESULTS: Young mice with increased IGF1R signaling exhibited superior cardiac function that progressively declined with aging in an accelerated fashion compared with wild-type animals, resulting in heart failure and a reduced lifespan. In contrast, mice with low cardiac IGF1R signaling exhibited inferior cardiac function early in life, but superior cardiac performance during aging, and increased maximum lifespan, as well. Mechanistically, the late-life detrimental effects of IGF1R activation correlated with suppressed autophagic flux and impaired oxidative phosphorylation in the heart. Low IGF1R activity consistently improved myocardial bioenergetics and function of the aging heart in an autophagy-dependent manner. In humans, failing hearts, but not those with compensated hypertrophy, displayed exaggerated IGF1R expression and signaling activity. CONCLUSIONS: Our findings indicate that the relationship between IGF1R signaling and cardiac health is not linear, but rather biphasic. Hence, pharmacological inhibitors of the IGF1 pathway, albeit unsuitable for young individuals, might be worth considering in older adults.


Asunto(s)
Factor I del Crecimiento Similar a la Insulina , Longevidad , Anciano , Animales , Promoción de la Salud , Humanos , Factor I del Crecimiento Similar a la Insulina/metabolismo , Masculino , Ratones , Miocitos Cardíacos/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Receptor IGF Tipo 1/genética , Receptor IGF Tipo 1/metabolismo
5.
J Clin Microbiol ; 61(8): e0190522, 2023 08 23.
Artículo en Inglés | MEDLINE | ID: mdl-37439667

RESUMEN

Mycoplasma bovis is a fastidious pathogen of cattle causing massive economic losses in the calf and dairy industries worldwide. Since there is no approved standard method for antimicrobial susceptibility testing (AST) of M. bovis, the Clinical and Laboratory Standards Institute has requested the development of a suitable method. Therefore, this study aimed at developing a method for harmonized broth microdilution AST of M. bovis. For this, 131 M. bovis field isolates and M. bovis strain DSM 22781T were collected and macrorestriction analysis was performed to select 15 epidemiologically unrelated M. bovis strains for method validation steps. To select a suitable broth for AST of M. bovis, growth determinations were performed using five media and growth curves were compiled. Then, susceptibility testing was performed considering the exact (precondition of five identical MICs) and essential (MIC mode, accepting a deviation of ±1 dilution step) MIC agreements to evaluate the reproducibility of MIC values using a panel of 16 antimicrobial agents. Subsequently, the remaining field isolates were tested and the suitability of quality control (QC) strains was assessed. Growth experiments showed that SP4 broth was the only one of the five media that yielded sufficient growth of M. bovis. Therefore, it was selected as the test medium for AST and homogeneous MIC values were obtained (exact and essential agreements of 36 to 100% and 92 to 100%, respectively). For all other isolates tested, easy-to-read MIC endpoints were determined with this medium. High overall MIC50 and/or MIC90 values were observed for aminoglycosides and macrolides, and some isolates showed elevated MICs of fluoroquinolones, gentamicin, and/or tiamulin. Since the MICs of four commonly used QC strains were partially not within their ranges, a 20-fold MIC testing of M. bovis DSM 22781T was performed and met the criteria for a new QC strain. For harmonized AST of M. bovis, SP4 broth seems to be suitable with an incubation time of 72 ± 2 h and further validation of M. bovis DSM 22781T as a future QC strain is recommended.


Asunto(s)
Antiinfecciosos , Mycoplasma bovis , Animales , Bovinos , Reproducibilidad de los Resultados , Antibacterianos/farmacología , Fluoroquinolonas , Medios de Cultivo , Pruebas de Sensibilidad Microbiana
6.
J Anat ; 242(1): 91-101, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-34958481

RESUMEN

Aging is associated with cardiac hypertrophy and progressive decline in heart function. One of the hallmarks of cellular aging is the dysfunction of mitochondria. These organelles occupy around 1/4 to 1/3 of the cardiomyocyte volume. During cardiac aging, the removal of defective or dysfunctional mitochondria by mitophagy as well as the dynamic equilibrium between mitochondrial fusion and fission is distorted. Here, we hypothesized that these changes affect the number of mitochondria and alter their three-dimensional (3D) characteristics in aged mouse hearts. The polyamine spermidine stimulates both mitophagy and mitochondrial biogenesis, and these are associated with improved cardiac function and prolonged lifespan. Therefore, we speculated that oral spermidine administration normalizes the number of mitochondria and their 3D morphology in aged myocardium. Young (4-months old) and old (24-months old) mice, treated or not treated with spermidine, were used in this study (n = 10 each). The number of mitochondria in the left ventricles was estimated by design-based stereology using the Euler-Poincaré characteristic based on a disector at the transmission electron microscopic level. The 3D morphology of mitochondria was investigated by 3D reconstruction (using manual contour drawing) from electron microscopic z-stacks obtained by focused ion beam scanning electron microscopy. The volume of the left ventricle and cardiomyocytes were significantly increased in aged mice with or without spermidine treatment. Although the number of mitochondria was similar in young and old control mice, it was significantly increased in aged mice treated with spermidine. The interfibrillar mitochondria from old mice exhibited a lower degree of organization and a greater variation in shape and size compared to young animals. The mitochondrial alignment along the myofibrils in the spermidine-treated mice appeared more regular than in control aged mice, however, old mitochondria from animals fed spermidine also showed a greater diversity of shape and size than young mitochondria. In conclusion, mitochondria of the aged mouse left ventricle exhibited changes in number and 3D ultrastructure that is likely the structural correlate of dysfunctional mitochondrial dynamics. Spermidine treatment reduced, at least in part, these morphological changes, indicating a beneficial effect on cardiac mitochondrial alterations associated with aging.


Asunto(s)
Miocardio , Espermidina , Ratones , Animales , Espermidina/farmacología , Espermidina/metabolismo , Miocitos Cardíacos/metabolismo , Mitocondrias , Suplementos Dietéticos
7.
Artículo en Inglés | MEDLINE | ID: mdl-37578899

RESUMEN

One novel Streptococcus strain (SQ9-PEAT) and two novel Staphylococcus strains (SQ8-PEAT and GRT3T) were isolated from faeces of a wild eastern grey squirrel. The strains were non-spore-forming, non-motile Gram-positive cocci, facultative anaerobes. The genomes for these strains were sequenced. The 16S rRNA gene and core-genome-based phylogenetic analyses showed that strain SQ9-PEAT was closely related to Streptococcus hyointestinalis, strain SQ8-PEAT to Staphylococcus pettenkoferi and Staphylococcus argensis, and strain GRT3T to Staphylococcus rostri, Staphylococcus muscae and Staphylococcus microti. Average nucleotide identity and pairwise digital DNA-DNA hybridization values calculated for these novel strains compared to type strain genomes of phylogenetically related species within the genera Streptococcus and Staphylococcus clearly revealed that strain SQ9-PEAT represents a novel species of the genus Streptococcus and strains SQ8-PEAT and GRT3T represent two novel species of the genus Staphylococcus. Phenotypical features of these novel type strains differed from the features of the type strains of other phylogenetically related species. MALDI-TOF mass spectrometry supported identification of these novel species. Based on these data, we propose one novel species of the genus Streptococcus, for which the name Streptococcus sciuri sp. nov. with the type strain SQ9-PEAT (=DSM 114656T=CCUG 76426T=NCTC 14727T) is proposed, and two novel species of the genus Staphylococcus, for which the names Staphylococcus marylandisciuri sp. nov. with the type strain SQ8-PEAT (=DSM 114685T=CCUG 76423T=NCTC 14723T) and Staphylococcus americanisciuri sp. nov. with the type strain GRT3T (=DSM 114696T=CCUG 76427T=NCTC 14722T) are proposed. The genome G+C contents are 38.29, 36.49 and 37.26 mol% and complete draft genome sizes are 1 692 266, 2 371 088 and 2 237 001 bp for strains SQ9-PEAT, SQ8-PEAT and GRT3T, respectively.


Asunto(s)
Ácidos Grasos , Streptococcus , Filogenia , ARN Ribosómico 16S/genética , Composición de Base , ADN Bacteriano/genética , Técnicas de Tipificación Bacteriana , Ácidos Grasos/química , Análisis de Secuencia de ADN , Heces , Streptococcus/genética , Staphylococcus
8.
Curr Microbiol ; 80(8): 253, 2023 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-37354372

RESUMEN

A novel Neisseria strain, designated CSL10203-ORH2T, was isolated from the oropharynx of a wild California sea lion (Zalophus californianus) that was admitted to The Marine Mammal Center in California, USA. The strain was originally cultured from an oropharyngeal swab on BD Phenylethyl Alcohol (PEA) agar with 5% sheep blood under aerobic conditions. Phylogenetic analyses based on 16S rRNA, rplF, and rpoB gene sequences and the core genome sequences indicated that the strain was most closely related to only N. zalophi CSL 7565T. The average nucleotide identity and digital DNA-DNA hybridization values between strain CSL10203-ORH2T and the closely related species N. zalophi CSL 7565T were 89.84 and 39.70%, respectively, which were significantly lower than the accepted species-defined thresholds for describing novel prokaryotic species at the genomic level. Both type strains were phenotypically similar but can be easily and unambiguously distinguished between each other by the analysis of their housekeeping genes, e.g., rpoB, gyrB, or argF. The major fatty acids in both type strains were C12:0, C16:0, C16:1-c9, and C18:1-c11. Based on the genomic, phenotypic, and phylogenetic properties, the novel strain represents a novel species of the genus Neisseria, for which the name Neisseria montereyensis sp. nov. with the type strain CSL10203-ORH2T (= DSM 114706T = CCUG 76428T = NCTC 14721T) is proposed. The genome G + C content is 45.84% and the complete draft genome size is 2,310,535 bp.


Asunto(s)
Leones Marinos , Animales , Ovinos/genética , Leones Marinos/genética , Filogenia , Técnicas de Tipificación Bacteriana , Neisseria/genética , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Ácidos Grasos , Genómica , Orofaringe , ADN , ADN Bacteriano/genética , Hibridación de Ácido Nucleico , Fosfolípidos
9.
Artículo en Inglés | MEDLINE | ID: mdl-35776769

RESUMEN

Seven genotypically distinct strains assigned to the genus Erysipelothrix were isolated in different laboratories from several animal sources. Strain D17_0559-3-2-1T and three further strains were isolated from samples of duck, pig and goose. The strains had >99 % 16S rRNA gene sequence similarity to each other and to strain VA92-K48T and two further strains isolated from samples of medical leech and a turtle. The closest related type strains to the seven strains were those of Erysipelothrix inopinata (96.74 %) and Erysipelothrix rhusiopathiae (95.93 %). Average nucleotide identity, amino acid identity and in silico DNA-DNA hybridization results showed that the strains represented two separate novel species. One further phylogenetically distinct strain (165301687T) was isolated from fox urine. The strain had highest 16S rRNA gene sequence similarity to the type strains of Erysipelothrix tonsillarum (95.67 %), followed by Erysipelothrix piscisicarius (95.58 %) and Erysipelothrix larvae (94.22 %) and represented a further novel species. Chemotaxonomic and physiological data of the novel strains were assessed, but failed to unequivocally differentiate the novel species from existing members of the genus. MALDI-TOF MS data proved the discrimination of at least strain 165301687T from all currently described species. Based on the presented phylogenomic and physiological data, we propose three novel species, Erysipelothrix anatis sp. nov. with strain D17_0559-3-2-1T (=DSM 111258T= CIP 111884T=CCM 9044T) as type strain, Erysipelothrix aquatica sp. nov. with strain VA92-K48T (=DSM 106012T=LMG 30351T=CIP 111492T) as type strain and Erysipelothrix urinaevulpis sp. nov. with strain 165301687T (=DSM 106013T= LMG 30352T= CIP 111494T) as type strain.


Asunto(s)
Escarabajos , Erysipelothrix , Animales , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Erysipelothrix/genética , Ácidos Grasos/química , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Porcinos
10.
Microb Ecol ; 83(1): 18-33, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33745062

RESUMEN

Large baleen and toothed whales play crucial ecological roles in oceans; nonetheless, very little is known about their intestinal microbiomes. Based on striking differences in natural history and thus in feeding behaviours, it can be expected that intestinal microbiomes of large baleen whales and toothed whales are different. To test this hypothesis, the phylogenetic composition of faecal microbiomes was investigated by a 16S rRNA gene amplicon sequence-based approach for Bacteria and Archaea. Faecal samples from free-ranging large whales collected off the Azores Archipelago (Portugal) were used, comprising 13 individual baleen whales (one sei, two blue and ten fin whales) and four sperm whales. The phylogenetic composition of the Bacteria faecal microbiomes of baleen and toothed whales showed no significant differences at the phylum level. However, significant differences were detected at the family and genus levels. Most abundant phyla were Firmicutes, Bacteroidetes, Proteobacteria, Tenericutes and Spirochaeta. Few highly abundant bacterial genera were identified as key taxa with a high contribution to differences among baleen and toothed whales microbiomes. Only few archaeal sequences were detected, primarily Methanomassiliicoccales representing potential methanogenic Archaea. This is the first study that directly compares the faecal bacterial and archaeal microbiomes of free-ranging baleen and toothed whales which represent the two parvorders of Cetacea which members are fully aquatic large mammals which were evolutionary split millions of years ago.


Asunto(s)
Balaenoptera , Microbiota , Animales , Filogenia , ARN Ribosómico 16S/genética , Cachalote/microbiología
11.
Antonie Van Leeuwenhoek ; 115(7): 857-870, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35489013

RESUMEN

Bovine mastitis causes enormous economic losses in the dairy industry with Streptococcus uberis as one of the most common bacterial pathogens causing clinical and subclinical variations. In most cases mastitis can be cured by intramammary administration of antimicrobial agents. However, the severity of the clinical manifestations can vary greatly from mild to severe symtoms. In this study, a comparative genomic analysis of 24 S. uberis isolates from three dairy farms in Germany, affected by different courses of infection was conducted. While there were sporadic mild infections in farm A and B, a large number of infections were observed within a very short period of time in farm C. The comparison of virulence genes, antimicrobial resistance genes and prophage regions revealed no features that might be responsible for this severe course. However, almost all isolates from farm C showed the same, novel MLST profile (ST1373), thus a clonal outbreak cannot be excluded, whereby the actual reason for the particular virulence remains unknown. This study demonstrates the importance of extensive metagenomic studies, including the host genomes and the environment, to gain further evidence on the pathogenicity of S. uberis.


Asunto(s)
Mastitis Bovina , Infecciones Estreptocócicas , Animales , Bovinos , Femenino , Mastitis Bovina/epidemiología , Mastitis Bovina/microbiología , Tipificación de Secuencias Multilocus , Infecciones Estreptocócicas/microbiología , Infecciones Estreptocócicas/veterinaria , Streptococcus/genética
12.
Mol Cell ; 53(5): 710-25, 2014 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-24560926

RESUMEN

Acetyl-coenzyme A (AcCoA) is a major integrator of the nutritional status at the crossroads of fat, sugar, and protein catabolism. Here we show that nutrient starvation causes rapid depletion of AcCoA. AcCoA depletion entailed the commensurate reduction in the overall acetylation of cytoplasmic proteins, as well as the induction of autophagy, a homeostatic process of self-digestion. Multiple distinct manipulations designed to increase or reduce cytosolic AcCoA led to the suppression or induction of autophagy, respectively, both in cultured human cells and in mice. Moreover, maintenance of high AcCoA levels inhibited maladaptive autophagy in a model of cardiac pressure overload. Depletion of AcCoA reduced the activity of the acetyltransferase EP300, and EP300 was required for the suppression of autophagy by high AcCoA levels. Altogether, our results indicate that cytosolic AcCoA functions as a central metabolic regulator of autophagy, thus delineating AcCoA-centered pharmacological strategies that allow for the therapeutic manipulation of autophagy.


Asunto(s)
Acetilcoenzima A/química , Autofagia , Citosol/enzimología , Regulación Enzimológica de la Expresión Génica , Adenosina Trifosfato/química , Animales , Línea Celular Tumoral , Núcleo Celular/metabolismo , Citoplasma/metabolismo , Citosol/metabolismo , Proteína p300 Asociada a E1A/química , Proteínas Fluorescentes Verdes/metabolismo , Células HCT116 , Células HeLa , Humanos , Ácidos Cetoglutáricos/química , Ratones , Ratones Endogámicos C57BL , Microscopía Fluorescente , Mitocondrias/metabolismo , ARN Interferente Pequeño/metabolismo
13.
Clin Infect Dis ; 72(10): 1826-1829, 2021 05 18.
Artículo en Inglés | MEDLINE | ID: mdl-32658299

RESUMEN

Rat bite fever (RBF) is predominantly caused by Streptobacillus moniliformis. We report a human infection with Streptobacillus felis. Clinical presentation was consistent with RBF, but serologic testing was negative for S moniliformis. Eventually, S felis-specific sequences were detected in skin lesions of the patient and in the oropharynx of local cats.


Asunto(s)
Fiebre por Mordedura de Rata , Streptobacillus , Animales , Gatos , Humanos , Masculino , Orofaringe , Fiebre por Mordedura de Rata/diagnóstico , Fiebre por Mordedura de Rata/tratamiento farmacológico
14.
BMC Genomics ; 22(1): 110, 2021 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-33563210

RESUMEN

BACKGROUND: The accumulation of intracellular fat depots is a polygenic trait. Therefore, the extent of lipid storage in the individuals of a species covers a broad range and is determined by many genetic factors. Quantitative trait loci analysis can be used to identify those genetic differences between two strains of the same species that are responsible for the differences in a given phenotype. We used this method and complementary approaches to identify genes in the yeast Saccharomyces cerevisiae that are involved in neutral lipid storage. RESULTS: We selected two yeast strains, the laboratory strain BY4741 and the wine yeast AWRI1631, with a more than two-fold difference in neutral lipid content. After crossing, sporulation and germination, we used fluorescence activated cell sorting to isolate a subpopulation of cells with the highest neutral lipid content from the pool of segregants. Whole genome sequencing of this subpopulation and of the unsorted pool of segregants implicated several loci that are involved in lipid accumulation. Three of the identified genes, PIG1, PHO23 and RML2, were investigated in more detail. Deletions of these genes and the exchange of the alleles between the two parental strains confirmed that the encoded proteins contribute to neutral lipid storage in S. cerevisiae and that PIG1, PHO23 and RML2 are the major causative genes. Backcrossing of one of the segregants with the parental strains for seven generations revealed additional regions in the genomes of both strains with potential causative genes for the high lipid accumulation phenotype. CONCLUSIONS: We identified several genes that contribute to the phenotype of lipid accumulation in an allele-specific manner. Surprisingly, no allelic variations of genes with known functions in lipid metabolism were found, indicating that the level of storage lipid accumulation is determined by many cellular processes that are not directly related to lipid metabolism.


Asunto(s)
Proteínas de Saccharomyces cerevisiae , Vino , Mapeo Cromosómico , Humanos , Proteínas Nucleares , Sitios de Carácter Cuantitativo , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética
15.
Emerg Infect Dis ; 27(10): 2686-2690, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34545798

RESUMEN

Toxin-producing Corynebacterium ulcerans, a causative agent of diphtheria in humans, was isolated from 53 hedgehogs in Belgium during the spring of 2020. Isolates showed low levels of acquired antimicrobial drug resistance. Strain diversity suggests emergence from an endemic situation. These findings stress the need for raising public awareness and improved wildlife disease surveillance.


Asunto(s)
Infecciones por Corynebacterium , Erizos , Animales , Corynebacterium/genética , Infecciones por Corynebacterium/diagnóstico , Infecciones por Corynebacterium/epidemiología , Toxina Diftérica , Humanos
16.
Annu Rev Nutr ; 40: 135-159, 2020 09 23.
Artículo en Inglés | MEDLINE | ID: mdl-32634331

RESUMEN

Natural polyamines (spermidine and spermine) are small, positively charged molecules that are ubiquitously found within organisms and cells. They exert numerous (intra)cellular functions and have been implicated to protect against several age-related diseases. Although polyamine levels decline in a complex age-dependent, tissue-, and cell type-specific manner, they are maintained in healthy nonagenarians and centenarians. Increased polyamine levels, including through enhanced dietary intake, have been consistently linked to improved health and reduced overall mortality. In preclinical models, dietary supplementation with spermidine prolongs life span and health span. In this review, we highlight salient aspects of nutritional polyamine intake and summarize the current knowledge of organismal and cellular uptake and distribution of dietary (and gastrointestinal) polyamines and their impact on human health. We further summarize clinical and epidemiological studies of dietary polyamines.


Asunto(s)
Análisis de los Alimentos , Valor Nutritivo , Espermidina/metabolismo , Animales , Dieta , Humanos
17.
Artículo en Inglés | MEDLINE | ID: mdl-33999792

RESUMEN

Four novel independent strains of Streptococcus spp. were isolated from faeces of alpaca (SL1232T), cattle (KCJ4950), and from respiratory tract of wild California sea lions (CSL7508T, CSL7591T). The strains were indole-, oxidase- and catalase-negative, non-spore-forming, non-motile Gram-positive cocci in short and long chains, facultative anaerobes. The 16S rRNA gene of SL1232T and KCJ4950 shared 99.40-99.60% nucleotide similarity to strains of S. equinus, S. lutetiensis, S. infantarius, and the 16S rRNA gene of CSL7508T and CSL7591T demonstrated 98.72 and 98.92% similarity, respectively, to S. marimammalium. All other known Streptococcus species had the 16S rRNA gene sequence similarities of ≤95%. The genomes were sequenced for the novel strains. Average nucleotide identity (ANI) analysis for strains SL1232T and KCJ4950, showed the highest similarity to S. equinus, S. lutetiensis, and S. infantarius with 85.21, 87.17, 88.47, 85.54, 87.47 and 88.89%, respectively, and strains CSL7508T and CSL7591T to S. marimammalium with 87.16 and 83.97%, respectively. Results of ANI were confirmed by pairwise digital DNA-DNA hybridization and phylogeny, which also revealed that the strains belong to three novel species of the genus Streptococcus. Phenotypical features of the novel species were in congruence with closely related members of the genus Streptococcus and gave negative reactions with the tested Lancefield serological groups (A-D, F and G). MALDI-TOF mass spectrometry supported identification of the species. Based on these data, we propose three novel species of the genus Streptococcus, for which the name Streptococcus vicugnae sp. nov. is proposed with the type strain SL1232T (=NCTC 14341T=DSM 110741T=CCUG 74371T), Streptococcus zalophi sp. nov. is proposed with the type strain CSL7508T (=NCTC 14410T=DSM 110742T=CCUG 74374T) and Streptococcus pacificus sp. nov. is proposed with the type strain CSL7591T (=NCTC 14455T=DSM 111148T=CCUG 74655T). The genome G+C content is 36.89, 34.85, and 35.34 % and draft genome sizes are 1906993, 1581094 and 1656080 bp for strains SL1232T, CSL7508T, and CSL7591T, respectively.


Asunto(s)
Camélidos del Nuevo Mundo/microbiología , Bovinos/microbiología , Filogenia , Leones Marinos/microbiología , Streptococcus/clasificación , Animales , Técnicas de Tipificación Bacteriana , Composición de Base , Secuencia de Bases , California , ADN Bacteriano/genética , Ácidos Grasos/química , Heces/microbiología , Florida , Maryland , Hibridación de Ácido Nucleico , ARN Ribosómico 16S/genética , Sistema Respiratorio/microbiología , Análisis de Secuencia de ADN , Streptococcus/aislamiento & purificación
18.
Antonie Van Leeuwenhoek ; 114(9): 1361-1371, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34170418

RESUMEN

Corynebacterium (C.) diphtheriae is one of the two etiological pathogens for human diphtheria with significant morbidity and mortality. Recently, members of its biovar Belfanti have been described as two novel species, C. belfantii and C. rouxii. The most important virulence factor and also the premise to cause diphtheria is the isolate's capacity to encode and express the diphtheria toxin (DT). In contrast to C. ulcerans, which represents a potentially zoonotic pathogen, C. diphtheriae (incl. the novel deduced species) has almost exclusively been found to comprise a human pathogen. We here report three rare cases of C. rouxii isolation from dogs suffering from disseminated poly-bacterial exsudative to purulent dermatitis and a traumatic labial defect, respectively. The isolates were identified as C. diphtheriae based on commercial biochemistry and matrix-assisted laser desorption/ionisation-time of flight mass spectrometry (MALDI-TOF MS) analysis. However, recently described specific spectral peaks were highly similar to spectra of C. rouxii, which was confirmed by whole genome sequencing. Further investigations of the dog isolates for the presence of DT by tox gene qPCR revealed negative results. The findings from this study point out that skin infections in companion animals can be colonized by uncommon and so believed human specific pathogens, thereby resembling the clinical signs of cutaneous diphtheria.


Asunto(s)
Infecciones por Corynebacterium , Corynebacterium diphtheriae , Difteria , Enfermedades de los Perros , Úlcera Cutánea , Animales , Corynebacterium/genética , Infecciones por Corynebacterium/veterinaria , Corynebacterium diphtheriae/genética , Difteria/veterinaria , Toxina Diftérica , Enfermedades de los Perros/microbiología , Perros , Úlcera Cutánea/microbiología , Úlcera Cutánea/veterinaria , Secuenciación Completa del Genoma
19.
Antonie Van Leeuwenhoek ; 114(3): 235-251, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33591460

RESUMEN

The Gram-stain-negative, oxidase negative, catalase positive strain KPC-SM-21T, isolated from a digestate of a storage tank of a mesophilic German biogas plant, was investigated by a polyphasic taxonomic approach. Phylogenetic identification based on the nearly full-length 16S rRNA gene revealed highest gene sequence similarity to Acinetobacter baumannii ATCC 19606T (97.0%). Phylogenetic trees calculated based on partial rpoB and gyrB gene sequences showed a distinct clustering of strain KPC-SM-21T with Acinetobacter gerneri DSM 14967T = CIP 107464T and not with A. baumannii, which was also supported in the five housekeeping genes multilocus sequence analysis based phylogeny. Average nucleotide identity values between whole genome sequences of strain KPC-SM-21T and next related type strains supported the novel species status. The DNA G + C content of strain KPC-SM-21T was 37.7 mol%. Whole-cell MALDI-TOF MS analysis supported the distinctness of the strain to type strains of next related Acinetobacter species. Predominant fatty acids were C18:1 ω9c (44.2%), C16:0 (21.7%) and a summed feature comprising C16:1 ω7c and/or iso-C15:0 2-OH (15.3%). Based on the obtained genotypic, phenotypic and chemotaxonomic data we concluded that strain KPC-SM-21T represents a novel species of the genus Acinetobacter, for which the name Acinetobacter stercoris sp. nov. is proposed. The type strain is KPC-SM-21T (= DSM 102168T = LMG 29413T).


Asunto(s)
Acinetobacter , Biocombustibles , Acinetobacter/genética , Anaerobiosis , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Ácidos Grasos/análisis , Hibridación de Ácido Nucleico , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN
20.
Dis Aquat Organ ; 145: 15-20, 2021 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-34080579

RESUMEN

Bufonid herpesvirus 1 (BfHV1) was initially described in 2014 from cases of mortalities and dermatitis in Swiss populations of the common toad Bufo bufo. We identified a closely related herpesvirus strain in a German common toad population affected by an ongoing epidemic of multifocal proliferative to ulcerative skin disease since 2018.


Asunto(s)
Bufo bufo , Herpesviridae , Animales , Alemania/epidemiología , Piel
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