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1.
Acta Med Port ; 37(1): 46-50, 2024 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-36919988

RESUMEN

Mycetoma is caused by the subcutaneous inoculation of filamentous fungi or aerobic filamentous bacteria. Cellulosimicrobium cellulans is a gram-positive bacterium from the order Actinomycetales that rarely causes human disease. The diagnosis is based on the clinical presentation and identification of the causative microorganism. We present a short literature review regarding the case report of a young man diagnosed with actinomycetoma due to Cellulosimicrobium cellulans and who received treatment with an association of amikacin and sulfamethoxazole/ trimethoprim (Welsh regimen).


Asunto(s)
Actinomycetales , Micetoma , Masculino , Humanos , Micetoma/diagnóstico , Micetoma/tratamiento farmacológico , Micetoma/microbiología , Antibacterianos/uso terapéutico , Guinea Bissau , Combinación Trimetoprim y Sulfametoxazol/uso terapéutico
2.
Int J Mycobacteriol ; 12(3): 345-349, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37721242

RESUMEN

Background: Over the past 10 years, the clinical importance of opportunistic bacteria of the order Actinomycetales has increased significantly. While many problems for the Mycobacterium tuberculosis complex have been solved, for nontuberculous mycobacteria, some questions remain open. These pathogens have a number of structural features that allow them to persist in the external environment for a long time. Methods: The main inclusion criteria were cultural characteristics in assessing the growth of microorganisms on solid egg media. If nontuberculous mycobacteria (NTM) growth was detected, identification signs were carried out using the DNA hybridization method. Subsequently, these cultures were identified using the matrix-assisted laser desorption/ionization-time-of-flight (MALDI-ToF) mass spectrometry method. In case of obtaining unacceptable results of identification from primary inoculations, re-identification to obtain pure cultures was carried out after transferring the material from primary media to agar media: 5% blood agar and universal chromogenic medium. When re-identifying isolated cultures using MALDI-ToF mass spectrometry, all isolated cultures were analyzed, regardless of whether they belonged to the NTM group or not. Results: DNA hybridization, which accounted for 59.5% of the total number of cultures included in the study, performed species identification of 188 strains. Using MALDI-ToF mass spectrometry, 345 strains were identified. Conclusion: The use of methods based on DNA hybridization makes it possible to identify quite accurately some of the most common NTM species. MALDI-ToF mass spectrometry is an important technique to allow species identification of most Actinomycetales. However, algorithms to standardize methods for their isolation from clinical material are needed.


Asunto(s)
Infecciones por Mycobacterium no Tuberculosas , Mycobacterium , Humanos , Micobacterias no Tuberculosas , Agar , Infecciones por Mycobacterium no Tuberculosas/microbiología , Medios de Cultivo , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , ADN
3.
Adv Biomed Res ; 12: 183, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37694256

RESUMEN

Background: The current study is an attempt to register the alterations in the immunological and histological parameters in mice arising from the administration of Dietza maris (D. maris) in order to confirm its protective properties. Materials and Methods: Mice underwent 7 days of treatment with three doses of D. maris. Then, animals were scrutinized in terms of body weight, relative weight of organs, delayed type of hypersensitivity (DTH) response, and hemagglutination titer (HT). The determination of villus height, villus width, crypt depth, villus/crypt ratio (V/C), Goblet cells, and intestinal epithelial lymphocyte (IEL) density in villi was carried out. Results: A boosted DTH response was observed as a result of bacteria at medium dose. A variation was noted between the hemagglutinin titer of the control group and that of the high-dose group. Crypt depth, villus width, and villus height manifested alterations. High-dose-treated mice demonstrated proliferation of Goblet cells in the villi, whereas both in medium- and high-dose-treated mice, a distribution of IELs in the villus epithelium was noted. Overall, D. maris showed a stimulatory effect on immune functions in mice. Thus, thanks to improved cellular and humoral immunity and the increased quality of intestine function, we believe that D. maris promises novel therapeutic applications in the future. Conclusion: The attained findings lend credence to immuno-stimulatory effects arising from the capacity of D. maris to function as immunological adjuvants and to enhance humoral and cellular immunity as well as the intestinal structure and function.

5.
Enferm Infecc Microbiol Clin (Engl Ed) ; 40(10): 562-567, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36464473

RESUMEN

INTRODUCTION: The incidence of infections caused by aerobic actinomycetes is increasing. Recent changes in taxonomy and the variability in susceptibility patterns among species make necessary a proper identification and antibiotic susceptibility testing. MATERIAL AND METHODS: Fifty-three strains of aerobic actinomycetes were identified by MALDI-TOF MS using the VITEK MS Mycobacterium/Nocardia kit (bioMérieux, France) in a tertiary hospital in Spain during a six-year period. Antimicrobial susceptibility testing of the isolates was performed using the Sensititre Rapmycoi microdilution panel (Thermo Fisher Scientific, Massachusetts, USA). RESULTS: Forty strains of Nocardia spp. were identified in the study, being N. farcinica and N. cyriacigeorgica the most prevalent ones. All isolates were susceptible to linezolid and the resistance to amikacin was only observed in one isolate of Gordonia sputi. Resistance to cotrimoxazole was only found in five isolates. CONCLUSIONS: Routine identification and antimicrobial susceptibility testing of aerobic actinomycetes is advisable for an efficient identification of species and effective treatment.


Asunto(s)
Actinomycetales , Antiinfecciosos , Infecciones por Mycobacterium , Nocardia , Humanos , Linezolid
6.
Int J Mol Sci ; 23(23)2022 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-36499372

RESUMEN

Streptomyces are of great interest in the pharmaceutical industry as they produce a plethora of secondary metabolites that act as antibacterial and antifungal agents. They may thrive on their own in the soil, or associate with other organisms, such as plants or invertebrates. Some soil-derived strains exhibit hemolytic properties when cultivated on blood agar, raising the question of whether hemolysis could be a virulence factor of the bacteria. In this work we examined hemolytic compound production in 23 ß-hemolytic Streptomyces isolates; of these 12 were soil-derived, 10 were arthropod-associated, and 1 was plant-associated. An additional human-associated S. sp. TR1341 served as a control. Mass spectrometry analysis suggested synthesis of polyene molecules responsible for the hemolysis: candicidins, filipins, strevertene A, tetrafungin, and tetrin A, as well as four novel polyene compounds (denoted here as polyene A, B, C, and D) in individual liquid cultures or paired co-cultures. The non-polyene antifungal compounds actiphenol and surugamide A were also identified. The findings indicate that the ability of Streptomyces to produce cytolytic compounds (here manifested by hemolysis on blood agar) is an intrinsic feature of the bacteria in the soil environment and could even serve as a virulence factor when colonizing available host organisms. Additionally, a literature review of polyenes and non-polyene hemolytic metabolites produced by Streptomyces is presented.


Asunto(s)
Streptomyces , Humanos , Streptomyces/química , Antifúngicos/farmacología , Antifúngicos/química , Antibacterianos/farmacología , Antibacterianos/metabolismo , Polienos/farmacología , Polienos/química , Hemólisis , Factores de Virulencia/metabolismo
7.
Enferm. infecc. microbiol. clín. (Ed. impr.) ; 40(10): 562-567, dic. 2022. tab
Artículo en Español | IBECS | ID: ibc-212841

RESUMEN

Introduction: The incidence of infections caused by aerobic actinomycetes is increasing. Recent changes in taxonomy and the variability in susceptibility patterns among species make necessary a proper identification and antibiotic susceptibility testing. Material and methods: Fifty-three strains of aerobic actinomycetes were identified by MALDI-TOF MS using the VITEK MS Mycobacterium/Nocardia kit (bioMérieux, France) in a tertiary hospital in Spain during a six-year period. Antimicrobial susceptibility testing of the isolates was performed using the Sensititre Rapmycoi microdilution panel (Thermo Fisher Scientific, Massachusetts, USA). Results: Forty strains of Nocardia spp. were identified in the study, being N. farcinica and N. cyriacigeorgica the most prevalent ones. All isolates were susceptible to linezolid and the resistance to amikacin was only observed in one isolate of Gordonia sputi. Resistance to cotrimoxazole was only found in five isolates. Conclusions: Routine identification and antimicrobial susceptibility testing of aerobic actinomycetes is advisable for an efficient identification of species and effective treatment.(AU)


Introducción: La incidencia de infecciones por actinomicetos aerobios está aumentando. Los recientes cambios en la taxonomía y la variabilidad en la sensibilidad entre especies hacen necesaria una identificación y estudio de sensibilidad adecuados. Material y métodos: Se identificaron 53 cepas de actinomicetos aerobios mediante MALDI-TOF utilizando el kit VITEK-MS Mycobacterium/Nocardia (bioMérieux, Francia) en un hospital terciario español durante seis años. Los estudios de sensibilidad de los aislados se realizaron utilizando el panel de microdilución Sensititre Rapmycoi (Thermo Fisher Scientific, Massachusetts, EE. UU.). Resultados: Se identificaron 40 cepas de Nocardia spp., siendo Nocardia farcinica y Nocardia cyriacigeorgica las más prevalentes. Todos los aislados fueron sensibles a linezolid, y solo se detectó resistencia a amikacina en un aislado de Gordonia sputi. Solo se encontró resistencia al cotrimoxazol en cinco aislados. Conclusiones: Es aconsejable realizar la identificación de rutina y las pruebas de sensibilidad antimicrobiana de los actinomicetos aerobios para conseguir una identificación eficiente de las especies y un tratamiento eficaz.(AU)


Asunto(s)
Humanos , Masculino , Femenino , Técnicas In Vitro , Epidemiología , Sensibilidad y Especificidad , Actinomycetales , Infecciones por Actinomycetales , Nocardia , Bacteria Gordonia , Enfermedades Transmisibles , España
8.
Curr Issues Mol Biol ; 44(2): 889-927, 2022 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-35723345

RESUMEN

The genus of Curtobacterium, belonging to the Microbacteriaceae family of the Actinomycetales order, includes economically significant pathogenic bacteria of soybeans and other agricultural crops. Thorough phylogenetic and full-genome analysis using the latest genomic data has demonstrated a complex and contradictory taxonomic picture within the group of organisms classified as the Curtobacterium species. Based on these data, it is possible to delineate about 50 new species and to reclassify a substantial part of the Curtobacterium strains. It is suggested that 53 strains, including most of the Curtobacterium flaccumfaciens pathovars, can compose a monophyletic group classified as C. flaccumfaciens. A genomic analysis using the most recent inventory of bacterial chromosomal and plasmid genomes deposited to GenBank confirmed the possible role of Microbacteriaceae plasmids in pathogenicity and demonstrated the existence of a group of related plasmids carrying virulence factors and possessing a gene distantly related to DNA polymerase found in bacteriophages and archaeal and eukaryotic viruses. A PCR diagnostic assay specific to the genus Curtobacterium was developed and tested. The presented results assist in the understanding of the evolutionary relations within the genus and can lay the foundation for further taxonomic updates.

9.
Enferm Infecc Microbiol Clin (Engl Ed) ; 40(5): 255-257, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35577444

RESUMEN

PURPOSE: Gordonia species are known to be opportunistic human pathogens causing secondary infections. We present the second case in the world of endocarditis caused by Gordonia bronchialis and a review of all the cases of endocarditis caused by Gordonia spp. METHODS: The identification was performed by matrix-assisted desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) and 16S rRNA gene sequencing were performed to confirm the identification. Antimicrobial susceptibility was performed by MIC test Strip on Mueller-Hinton agar supplemented with 5% defibrinated sheep blood according to Clinical and Laboratory Standards Institute. RESULTS: Pacemaker-induced endocarditis due to Gordonia bronchialis infection was determined in an 88-year old woman. The patient was treated with ceftriaxone and ciprofloxacin until completing 6 weeks from the pacemaker explant with a good evolution. CONCLUSION: The case presented supports the pathogenic role of Gordonia bronchialis as an opportunistic pathogen and highlights the high risk of suffering infections caused by environmental bacteria.


Asunto(s)
Endocarditis , Bacteria Gordonia , Marcapaso Artificial , Actinobacteria , Animales , Bacteria Gordonia/genética , Humanos , Marcapaso Artificial/efectos adversos , ARN Ribosómico 16S/genética , Ovinos/genética
10.
Artículo en Inglés | IBECS | ID: ibc-203500

RESUMEN

PurposeGordonia species are known to be opportunistic human pathogens causing secondary infections. We present the second case in the world of endocarditis caused by Gordonia bronchialis and a review of all the cases of endocarditis caused by Gordonia spp.MethodsThe identification was performed by matrix-assisted desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) and 16S rRNA gene sequencing were performed to confirm the identification. Antimicrobial susceptibility was performed by MIC test Strip on Mueller-Hinton agar supplemented with 5% defibrinated sheep blood according to Clinical and Laboratory Standards Institute.ResultsPacemaker-induced endocarditis due to Gordonia bronchialis infection was determined in an 88-year old woman. The patient was treated with ceftriaxone and ciprofloxacin until completing 6 weeks from the pacemaker explant with a good evolution.ConclusionThe case presented supports the pathogenic role of Gordonia bronchialis as an opportunistic pathogen and highlights the high risk of suffering infections caused by environmental bacteria.


ObjetivoLas especies de Gordonia son patógenos humanos oportunistas que causan infecciones secundarias. Presentamos el segundo caso en el mundo de endocarditis causada por Gordonia bronchialis, así como una revisión de todos los casos de endocarditis causados por Gordonia spp.MétodosLa identificación fue realizada mediante espectrometría de masas MALDI-TOF MS, y se confirmó mediante secuenciación del gen 16S rRNA. La susceptibilidad antimicrobiana se realizó mediante tiras reactivas MIC en agar Müller-Hinton suplementado con un 5% de sangre ovina desfibrinada, conforme al Clinical and Laboratory Standards Institute (CLSI).ResultadosLa endocarditis del marcapasos debido a infección por Gordonia bronchialis se encontró en una mujer de 88 años. La paciente fue tratada con ceftriaxona y ciprofloxacina hasta completar el periodo de 6 semanas desde el explante del marcapasos, con buena evolución.ConclusiónEste caso respalda el rol patogénico de Gordonia bronchialis como patógeno oportunista, subrayando el alto riesgo de padecer infecciones causadas por bacterias ambientales.


Asunto(s)
Humanos , Femenino , Anciano , Ciencias de la Salud , Endocarditis , Marcapaso Artificial , Bacteria Gordonia , Atención Dirigida al Paciente , Enfermedades Transmisibles , Microbiología , Estudios de Casos y Controles , Ceftriaxona , Ciprofloxacina
11.
Univ. salud ; 24(1): 85-94, ene.-abr. 2022. tab, graf
Artículo en Español | LILACS, COLNAL | ID: biblio-1361189

RESUMEN

Introducción: La resistencia a los antimicrobianos (RAM) es un problema de salud pública que manifiesta la disminuida eficacia de estos agentes en la prevención y tratamiento de una proporción cada vez más amplia de patologías. Los actinomicetos son un grupo bacteriano importante de productores de metabolitos activos contra patógenos. Objetivo: Aislar actinomicetos del bosque tropical de Nariño, con potencial producción de metabolitos inhibitorios contra bacterias multidrogo-resistentes. Materiales y métodos: Se tomaron muestras de suelo de Bosque Tropical Húmedo de la Reserva Natural del Río Ñambí, se analizaron microbiológica y molecularmente. Se estimuló la producción in vitro de metabolitos secundarios y evaluó el efecto inhibitorio de estos extractos contra las bacterias multidrogo-resistentes Escherichia coli y Staphylococcus aureus. Resultados: Se obtuvieron 11 aislados presuntivos, se confirmó que cuatro de ellos correspondieron al género Streptomyces sp. Las pruebas de inhibición contra bacterias multidrogo-resistentes E. coli y S. aureus, permitieron verificar que el aislado P3772 fue el más eficiente en la inhibición de los patógenos. Conclusiones: Todos los actinomicetos evaluados presentan actividad antibacteriana contra al menos una de las bacterias patógenas estudiadas; destacando el aislado P3772, que inhibe a E. coli y S. aureus. Se espera caracterizar los compuestos vinculados a la actividad antibacteriana.


Introduction: Antimicrobial resistance (AR) is a public health problem that reveals the diminished efficacy of these agents in the prevention and treatment of an increasingly larger number of pathologies. Actinomycetes are an important bacterial producer group of metabolites that are active against pathogens. Objective: To isolate actinomycetes from the tropical forest of Nariño (Colombia), which have the potential to produce inhibitory metabolites against multi-drug resistant bacteria. Materials and methods: Soil samples were taken from the Humid Tropical Forest of the Río Ńambí Natural Reserve and analyzed through microbiological and molecular assays. In vitro production of secondary metabolites was first stimulated, followed by the assessment of the inhibitory effect of these extracts against multi-drug resistant Escherichia coli and Staphylococcus aureus. Results: 11 presumptive isolates were obtained, confirming that four of them corresponded to the Streptomyces sp. genus. The bacterial isolate P3772 was identified as the one with the highest inhibitory effect against multi-drug resistant E. coli and S. aureus. Conclusions: All the actinomycetes evaluated presented antibacterial activity. The isolate P3772 stands out, which inhibited both E. coli and S. aureus. The compounds associated with this antibacterial activity will be characterized in future studies.


Asunto(s)
Humanos , Masculino , Femenino , Bacterias , Antiinfecciosos , Staphylococcus aureus , Actinobacteria , Farmacorresistencia Bacteriana , Escherichia coli , Antibacterianos
12.
Metabolites ; 12(3)2022 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-35323689

RESUMEN

Anti-virulence agents are non-bacteriostatic and non-bactericidal emerging therapeutic options which hamper the production of virulence factors in pathogenic flora. In Staphylococcus aureus and Enterococcus faecalis, regulation of virulence genes' expression occurs through the cyclic peptide-mediated accessory gene regulator (agr) and its ortholog fsr quorum sensing systems, respectively. In the present study, we screened a set of 54 actinomycetales secondary metabolites as novel anti-virulence compounds targeting quorum sensing system of the Gram-positive bacteria. The results indicated that four compounds, Phenalinolactones A-D, BU-4664LMe, 4,5-dehydrogeldamycin, and Questinomycin A, potentially inhibit the agr quorum sensing system and hemolytic activity of S. aureus. On the other hand, Decatromicin A and B, Okilactomycin, Rishirilide A, Abyssomicin I, and Rebeccamycin selectively blocked the fsr quorum sensing system and the gelatinase production in E. faecalis at sub-lethal concentrations. Interestingly, Synerazol uniquely showed the capability to inhibit both fsr and agr quorum sensing systems. Further, in silico molecular docking studies were performed which provided closer insights into the mode of action of these compounds and proposed that the inhibitory activity of these compounds could be attributed to their potential ability to bind to the ATP-active site of S. aureus AgrA. Taken together, our study highlights the potential of actinomycetales secondary metabolites with diverse structures as anti-virulence quorum sensing inhibitors.

13.
J Appl Microbiol ; 132(3): 2475-2487, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34773307

RESUMEN

AIMS: Geosmin is associated with off-flavour problems in recirculating aquaculture systems (RAS) and represents an economic problem for the aquaculture industry. This study aims at investigating factors influencing the composition of the bacterial microbiota, in particular the presence of geosmin producers and the environmental and farming factors favouring geosmin accumulation. METHODS AND RESULTS: Several water quality parameters were correlated to the composition of the microbiota with special emphasis on the presence of geosmin producers within 26 different RAS from four European countries. Three novel groups of geosmin-producing bacteria were quantified to identify potential correlations with geosmin concentration. CONCLUSIONS: The microbiome differed significantly between systems. However, phosphate levels, calcium levels and redox potential correlated to geosmin concentration in the water and the presence of the Actinomycetales geosmin-producers but not with the presence of other groups of geosmin-producing bacteria. Oxygen levels and conductivity were found to negatively correlate with geosmin concentration. A large proportion of the detected geosmin producers represented novel taxonomic groups not previously linked with this activity. SIGNIFICANCE AND IMPACT OF THE STUDY: These results improve our understanding of the diversity of microbiota in RAS and the water quality parameters favouring the populations of geosmin-producing bacteria and the production of geosmin.


Asunto(s)
Canfanos , Calidad del Agua , Acuicultura/métodos , Canfanos/análisis , Naftoles/análisis
14.
Iran J Microbiol ; 13(1): 81-90, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33889366

RESUMEN

BACKGROUND AND OBJECTIVES: Tsukamurella species are Gram-positive rods that exist in a broad range of environments. In this study, the efficacy of heat-killed Tsukamurella inchonensis on growth performance, intestinal morphology, and humoral immune responses of broiler chicken was evaluated. MATERIALS AND METHODS: Ross broiler chicks in the cage were randomly allocated to five groups. Trail diets were prepared by adding 106 cells per bird of heat-killed T. inchonensis into the basal trading diet for group 1 continuously dosed for 24 h from day 1 to day 13, and for group 2, 24 h on days 1 to 5; 8; 9, 12 and 13. Group 3 was received 106 bacteria as a subcutaneous injection on days 1, 6, and 12. Groups 4 and 5 were not received T. inchonensis during the experiment period. RESULTS: Feed intake (FI) and feed conversion ratio (FCR) were not altered by different delivery methods of T. inchonensis supplementation. The pulsed dosed in feed tended to provide higher body weight gain (BWG) than the negative control groups. T. inchonensis treatments, never less of the ways of delivery, boosted (P<0.05) the antibody titers to Newcastle disease virus (NDV), and avian influenza (AI) (H9N2) virus, especially when broiler chickens treated with pulse dosed in the feed. The most significant intestinal development (p<0.05) was observed between groups 1 and 2. There were no significant differences in the thymus, liver, and bursa of Fabricius relative weight. Still, there were significant increases in the relative weight of spleen on day 14 in vaccinated chickens treated with T. inchonensis pulse dosed. CONCLUSION: It seems that the supplementation of T. inchonensis in the broiler diet can improve intestinal morphology and humoral immune response, which was represented by increased antibody response to NDV, and AI vaccines significantly, but it cannot affect FI and FCR.

15.
Artículo en Inglés, Español | MEDLINE | ID: mdl-33812738

RESUMEN

INTRODUCTION: The incidence of infections caused by aerobic actinomycetes is increasing. Recent changes in taxonomy and the variability in susceptibility patterns among species make necessary a proper identification and antibiotic susceptibility testing. MATERIAL AND METHODS: Fifty-three strains of aerobic actinomycetes were identified by MALDI-TOF MS using the VITEK MS Mycobacterium/Nocardia kit (bioMérieux, France) in a tertiary hospital in Spain during a six-year period. Antimicrobial susceptibility testing of the isolates was performed using the Sensititre Rapmycoi microdilution panel (Thermo Fisher Scientific, Massachusetts, USA). RESULTS: Forty strains of Nocardia spp. were identified in the study, being N. farcinica and N. cyriacigeorgica the most prevalent ones. All isolates were susceptible to linezolid and the resistance to amikacin was only observed in one isolate of Gordonia sputi. Resistance to cotrimoxazole was only found in five isolates. CONCLUSIONS: Routine identification and antimicrobial susceptibility testing of aerobic actinomycetes is advisable for an efficient identification of species and effective treatment.

16.
Artículo en Inglés, Español | MEDLINE | ID: mdl-33446400

RESUMEN

PURPOSE: Gordonia species are known to be opportunistic human pathogens causing secondary infections. We present the second case in the world of endocarditis caused by Gordonia bronchialis and a review of all the cases of endocarditis caused by Gordonia spp. METHODS: The identification was performed by matrix-assisted desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) and 16S rRNA gene sequencing were performed to confirm the identification. Antimicrobial susceptibility was performed by MIC test Strip on Mueller-Hinton agar supplemented with 5% defibrinated sheep blood according to Clinical and Laboratory Standards Institute. RESULTS: Pacemaker-induced endocarditis due to Gordonia bronchialis infection was determined in an 88-year old woman. The patient was treated with ceftriaxone and ciprofloxacin until completing 6 weeks from the pacemaker explant with a good evolution. CONCLUSION: The case presented supports the pathogenic role of Gordonia bronchialis as an opportunistic pathogen and highlights the high risk of suffering infections caused by environmental bacteria.

17.
Front Microbiol ; 11: 2008, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32973726

RESUMEN

MSMEG_4305 is a two-domain protein of Mycolicibacterium smegmatis (Mycobacterium smegmatis) (Mycolicibacterium smegmatis). The N-terminal domain of MSMEG_4305 encodes an RNase H type I. The C-terminal domain is a presumed CobC, predicted to be involved in the aerobic synthesis of vitamin B12. Both domains reach their maximum at distinct pH, approximately 8.5 and 4.5, respectively. The presence of the CobC domain influenced RNase activity in vitro in homolog Rv2228c. Here, we analyzed the role of MSMEG_4305 in vitamin B12 synthesis and the functional association between both domains in vivo in M. smegmatis. We used knock-out mutant of M. smegmatis, deficient in MSMEG_4305. Whole-cell lysates of the mutants strain contained a lower concentration of vitamin B12, as it determined with immunoenzimatic assay. We observed growth deficits, related to vitamin B12 production, on media containing sulfamethazine and propionate. Removal of the CobC domain of MSMEG_4305 in ΔrnhA background hardly affected the growth rate of M. smegmatis in vivo. The strain carrying truncation showed no fitness deficit in the competitive assay and it did not show increased level of RNA/DNA hybrids in its genome. We show that homologs of MSMEG_4305 are present only in the Actinomycetales phylogenetic branch (according to the old classification system). The domains of MSMEG_4305 homologs accumulate mutations at a different rate, while the linker region is highly variable. We conclude that MSMEG_4305 is a multidomain protein that most probably was fixed in the phylogenetic tree of life due to genetic drift.

19.
New Microbes New Infect ; 31: 100575, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31333849

RESUMEN

Varibaculum timonense sp. nov. strain Marseille-P3369T (= CSURP3369) is a new species from the order Actinomycetales that has been isolated from a fresh stool sample of a healthy French woman.

20.
Int J Mol Sci ; 20(11)2019 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-31167367

RESUMEN

Bacteria from the species Trueperella pyogenes are a part of the biota of skin and mucous membranes of the upper respiratory, gastrointestinal, or urogenital tracts of animals, but also, opportunistic pathogens. T. pyogenes causes a variety of purulent infections, such as metritis, mastitis, pneumonia, and abscesses, which, in livestock breeding, generate significant economic losses. Although this species has been known for a long time, many questions concerning the mechanisms of infection pathogenesis, as well as reservoirs and routes of transmission of bacteria, remain poorly understood. Pyolysin is a major known virulence factor of T. pyogenes that belongs to the family of cholesterol-dependent cytolysins. Its cytolytic activity is associated with transmembrane pore formation. Other putative virulence factors, including neuraminidases, extracellular matrix-binding proteins, fimbriae, and biofilm formation ability, contribute to the adhesion and colonization of the host tissues. However, data about the pathogen-host interactions that may be involved in the development of T. pyogenes infection are still limited. The aim of this review is to present the current knowledge about the pathogenic potential and virulence of T. pyogenes.


Asunto(s)
Actinomycetaceae/fisiología , Infecciones por Bacterias Grampositivas/microbiología , Actinomycetaceae/clasificación , Actinomycetaceae/patogenicidad , Animales , Toxinas Bacterianas/química , Toxinas Bacterianas/genética , Toxinas Bacterianas/inmunología , Reservorios de Enfermedades , Genoma Bacteriano , Genómica/métodos , Infecciones por Bacterias Grampositivas/inmunología , Infecciones por Bacterias Grampositivas/transmisión , Interacciones Huésped-Patógeno/inmunología , Humanos , Filogenia , Unión Proteica , Dominios y Motivos de Interacción de Proteínas , ARN Ribosómico 16S , Relación Estructura-Actividad , Virulencia , Factores de Virulencia/química , Factores de Virulencia/genética , Factores de Virulencia/inmunología
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