Bloodstream infection by Rhodococcus corynebacterioides in a pediatric patient diagnosed with high-risk retinoblastoma / Infección del torrente sanguíneo por Rhodococcus corynebacterioides en un paciente pediátrico con diagnóstico de retinoblastoma de alto riesgo

Abstract Rhodococcus is a pathogen that is known to cause infections in animals and humans, mainly in cases of immunocompromised patients. A case of a pediatric cancer patient suffering from a bloodstream infection caused by Rhodococcus corynebacterioides was described in this work. Gram positive rods were isolated from blood cultures. The target bacterium was identified using a combination of biochemical tests, the MALDI-TOF mass spectrometry technique, and the analysis of the 16S rRNA sequence. Moreover, an antimicrobial susceptibility test was performed using the E-test. The isolated bacterium was identified as R. corynebacterioides. The 3-year-old patient was successfully treated with vancomycin and meropenem. This is the first published report of R. corynebacterioides in a pediatric patient diagnosed with retinoblastoma that developed a bloodstream infection. R. corynebacterioides should be considered among the opportunistic infectious agents affecting pediatric cancer patients.

Resumen Rhodococcus es un patógeno conocido por causar infecciones en animales y humanos, principalmente en pacientes inmunocomprometidos. En este trabajo se describe el caso de un paciente pediátrico con cáncer que presentó una infección del torrente sanguíneo causada por Rhodococcus corynebacterioides. A partir de hemocultivos, se aislaron bacilos gram positivos. La bacteria diana fue identificada usando una combinación de pruebas bioquímicas, por espectrometría de masas MALDI-TOF y por el análisis de la secuencia del gen 16S ARNr. Además, se realizó una prueba de sensibilidad a los antimicrobianos utilizando E-test. La cepa bacteriana se identificó como R. corynebacterioides. El paciente, de 3 años, fue tratado con vancomicina y meropenem, exitosamente. Este es el primer reporte de R. corynebacterioides como agente causal de una infección del torrente sanguíneo en un paciente pediátrico con retinoblastoma. R. corynebacterioides debe considerarse entre los agentes infecciosos oportunistas que afectan a los pacientes pediátricos con cáncer.

Pyridine degradation characteristics of Rhodococcus sp. LV4 under high salinity conditions / 生物工程学报

Biodegradation of pyridine pollutant by microorganisms is one of the economical and effective methods to solve the environmental pollution of pyridine under high salinity conditions. To this end, screening of microorganisms with pyridine degradation capability and high salinity tolerance is an important prerequisite. In this paper, a salt-resistant pyridine degradation bacterium was isolated from the activated sludge of Shanxi coking wastewater treatment plant, and identified as a bacterium belonging to Rhodococcus on the basis of colony morphology and 16S rDNA gene phylogenetic analysis. Salt tolerance experiment showed that strain LV4 could grow and degrade pyridine with the initial concentration of 500 mg/L completely in 0%-6% saline environment. However, when the salinity was higher than 4%, strain LV4 grew slowly and the degradation time of pyridine by strain LV4 was significantly prolonged. Scanning electron microscopy showed that the cell division of strain LV4 became slower, and more granular extracellular polymeric substance (EPS) was induced to secrete in high salinity environment. When the salinity was not higher than 4%, strain LV4 responded to the high salinity environment mainly through increasing the protein content in EPS. The optimum conditions for pyridine degradation by strain LV4 at 4% salinity were 30 ℃, pH 7.0 and 120 r/min (DO 10.30 mg/L). Under these optimal conditions, strain LV4 could completely degrade pyridine with an initial concentration of 500 mg/L at a maximum rate of (29.10±0.18) mg/(L·h) after 12 h adaptation period, and the total organic carbon (TOC) removal efficiency reached 88.36%, indicating that stain LV4 has a good mineralization effect on pyridine. By analyzing the intermediate products in pyridine degradation process, it was speculated that strain LV4 achieved pyridine ring opening and degradation mainly through two metabolic pathways: pyridine-ring hydroxylation and pyridine-ring hydrogenation. The rapid degradation of pyridine by strain LV4 in high salinity environment indicates its application potential in the pollution control of high salinity pyridine environment.

Isolation, identification and characterization of a chloramphenicol-degrading bacterium / 生物工程学报

Microorganisms are the dominant players driving the degradation and transformation of chloramphenicol (CAP) in the environment. However, little bacterial strains are able to efficiently degrade and mineralize CAP, and the CAP degrading pathways mediated by oxidative reactions remain unclear. In this study, a highly efficient CAP-degrading microbial consortium, which mainly consists of Rhodococcus (relative abundance >70%), was obtained through an enrichment process using CAP-contaminated activated sludge as the inoculum. A bacterial strain CAP-2 capable of efficiently degrading CAP was isolated from the consortium and identified as Rhodococcus sp. by 16S rRNA gene analysis. Strain CAP-2 can efficiently degrade CAP under different nutrient conditions. Based on the biotransformation characteristics of the detected metabolite p-nitrobenzoic acid and the reported metabolites p-nitrobenzaldehyde and protocatechuate by strain CAP-2, a new oxidative pathway for the degradation of CAP was proposed. The side chain of CAP was oxidized and broken to generate p-nitrobenzaldehyde, which was further oxidized to p-nitrobenzoic acid. Strain CAP-2 can be used to further study the molecular mechanism of CAP catabolism, and has the potential to be used in in situ bioremediation of CAP-contaminated environment.

Optimisation of biodegradation conditions for waste canola oil by cold-adapted Rhodococcus sp. AQ5-07 from Antarctica

BACKGROUND: The potential waste canola oil-degrading ability of the cold-adapted Antarctic bacterial strain Rhodococcus sp. AQ5-07 was evaluated. Globally, increasing waste from food industries generates serious anthropogenic environmental risks that can threaten terrestrial and aquatic organisms and communities. The removal of oils such as canola oil from the environment and wastewater using biological approaches is desirable as the thermal process of oil degradation is expensive and ineffective. RESULTS: Rhodococcus sp. AQ5-07 was found to have high canola oil-degrading ability. Physico-cultural conditions influencing its activity were studied using one-factor-at-a-time (OFAT) and statistical optimisation approaches. Considerable degradation (78.60%) of 3% oil was achieved by this bacterium when incubated with 1.0 g/L ammonium sulphate, 0.3 g/L yeast extract, pH 7.5 and 10% inoculum at 10°C over a 72-h incubation period. Optimisation of the medium conditions using response surface methodology (RSM) resulted in a 9.01% increase in oil degradation (87.61%) when supplemented with 3.5% canola oil, 1.05 g/L ammonium sulphate, 0.28g/L yeast extract, pH 7.5 and 10% inoculum at 12.5°C over the same incubation period. The bacterium was able to tolerate an oil concentration of up to 4.0%, after which decreased bacterial growth and oil degradation were observed. CONCLUSIONS: These features make this strain worthy of examination for practical bioremediation of lipid-rich contaminated sites. This is the first report of any waste catering oil degradation by bacteria originating from Antarctica.

Rhodococcus equi, primer reporte de un caso de enfermedad diseminada en el Perú / Rhodococcus equi, first case report of disseminated disease in Peru

Resumen Presentamos el caso de un paciente con infección por virus de inmunodeficiencia humana (VIH) con recuento de LTCD4+ 49 céls/mm3, que consultó por un cuadro de siete meses de baja de peso, dolor abdominal, diarrea crónica y lesiones cutáneas gomosas. El mielocultivo y hemocultivos fueron positivos para Rhodococcus equi. Además, se observaron lesiones histológicas en piel e intestino compatibles con este agente como malacoplaquia, reacción granulomatosa y cuerpos de Michaelis-Gutmann. Se descartó compromiso pulmonar mediante tomografía de tórax. Recibió terapia antibacteriana combinada con claritromicina, imipenem y vancomicina. A pesar del tratamiento, el paciente evolucionó desfavorablemente y falleció.

Abstract We present the case of a patient with human immunodeficiency virus (HIV) with a LTCD4 + 49 cells/mm3, who was admitted due to a seven-month period of weight loss, abdominal pain, chronic diarrhea and rubbery skin lesions. Myeloculture and blood cultures were positive for Rhodococcus equi. In addition, histological lesions in the skin and intestine compatible with this agent were observed, such as malacoplachy, granulomatous reaction and Michaelis-Gutmann bodies. Pulmonary involvement was ruled out by chest tomography. The patient received antibacterial therapy combined with clarithromycin, imipenem, and vancomycin. Despite the treatment, the patient evolved unfavorably and died.

Clinical and pathological findings of Rhodococcus equi infection in foals / Achados clínicos e patológicos da infecção por Rhodococcus equi em potros

Infection by Rhodococcus equi is considered one of the major health concerns for foals worldwide. In order to better understand the disease's clinical and pathological features, we studied twenty cases of natural infection by R. equi in foals. These cases are characterized according to their clinical and pathological findings and immunohistochemical aspects. Necropsy, histologic examination, bacterial culture, R. equi and Pneumocystis spp. immunohistochemistry were performed. The foals had a mean age of 60 days and presented respiratory signs (11/20), hyperthermia (10/20), articular swelling (6/20), prostration (4/20), locomotor impairment (3/20) and diarrhea (3/20), among others. The main lesions were of pyogranulomatous pneumonia, seen in 19 foals, accompanied or not by pyogranulomatous lymphadenitis (10/20) and pyogranulomatous and ulcerative enterocolitis (5/20). Pyogranulomatous osteomyelitis was seen in 3 foals, one of which did not have pulmonary involvement. There was lymphoplasmacytic (4/20), lymphoplasmacytic and neutrophilic (1/20) or pyogranulomatous arthritis (1/20), affecting multiple or singular joints. Immunohistochemistry revealed to be a valuable tool for the detection of R. equi, confirming the diagnosis in all cases. Furthermore, pulmonary immunostaining for Pneumocystis spp. demonstrates that a coinfection with R. equi and this fungal agent is a common event in foals, seen in 13 cases.(AU)

Infecção por Rhodococcus equi é considerado um dos maiores problemas sanitários para potros em todo o mundo. Para melhor compreender a apresentação clínica e patológica da enfermidade, foram avaliados vinte casos de infecção natural por R. equi em potros. Os casos são caracterizados de acordo com seus achados clínicos e patológicos e aspectos imuno-histoquímicos. Foram realizados exames de necropsia, histologia, bacteriologia e imuno-histoquímica para R. equi e Pneumocystis spp. Os potros tinham idade media de 60 dias e apresentaram sinais respiratórios (11/20), hipertermia (10/20), aumento de volume articular (6/20), prostração (4/20), distúrbios locomotores (3/20) e diarreia (3/20), entre outros. As lesões mais importantes eram pneumonia piogranulomatosa, vista em 19 potros, acompanhada ou não por linfadenite piogranulomatosa (10/20) e enterocolite ulcerativa (5/20). Osteomielite piogranulomatosa foi constatada em três potros, um dos quais não apresentava envolvimento pulmonar. Artrites afetando uma ou múltiplas articulações eram caracterizadas por infiltrado linfoplasmocítico (4/20), linfoplasmocítico e neutrofílico (1/20) e piogranulomatoso (1/20). A imuno-histoquímica demonstrou ser uma ferramenta valiosa na detecção de R. equi, permitindo confirmar o diagnóstico em todos os casos avaliados. Além disso, a imuno-histoquímica para Pneumocystis spp. demonstra que a coinfecção por R. equi e o agente fúngico é um evento frequente em potros, constatado em 13 casos.(AU)

Biodegradation of 4-nitrophenol by a Rhodococcus species and a preliminary insight into its toxicoproteome based on mass spectrometry analysis

Aim: The objective of this study was to understand the possible fate of 4-NP through the molecular mechanism and to identify potential enzymes involved in 4-NP biodegradation by Rhodococcus sp. strain BUPNP1 Methodology: Biodegradation of 4-NP was detected spectrophotometrically at 400 nm and also confirmed by TLC and HPLC. Comparative study of proteomes was performed by 2-D gel electrophoresis followed by peptide mass fingerprinting and bioinformatic analysis to identify and/ or predict the possible functions of over-expressed proteins in 4-NP treated cells of BUNP1. Results: Utilization of 4-nitrophenol and its hydrolysis intermediate 4-nitrocatechol (4-NC) and 1,2,4-Benzenetriol as sole carbon source indicated the presence of genomic information encoding the enzyme necessary for the operation of 4-nitrophenol degradation pathway in the strain BUPNP1. It could transform 4-NP into 4-NC by monooxygenase whose major activity was detected during initial stage of degradation. The 4-NC further depleted in the medium to release nitrite ions. In order to investigate the molecular changes occurring during degradation, a comparative study of proteome profiles was carried out where; 4-nitrophenol treated cells were compared against cells grown on glucose as control. The comparative study indicated expression of several protein spots under 4-nitrophenol treated condition. Interpretation: This study showed the potential of BUPNP1 strain belonging to genus Rhodococcus towards induced expression of some unique proteins which might have possible role in 4-NP biodegradation process

Rhodococcus equi como causa de neumonía en el síndrome de inmunodeficiencia adquirida / Rhodococcus equi as a cause of pneumonia in the acquired immunodeficiency syndrome

RESUMEN Rhodococcus equi es un microorganismo emergente asociado a infecciones oportunistas en individuos inmunocomprometidos, especialmente en pacientes con infección por virus de inmunodeficiencia humana. Se desarrolló una búsqueda en la Biblioteca Virtual de Infomed, fueron revisados 215 trabajos científicos sin limitación de año y país, seleccionándose 55. El rhodococcus es un patógeno intracelular capaz de crecer y persistir dentro de los macrófagos que expresan en su superficie el receptor Mac-1 (CD11b/CC18), y posteriormente destruirlos. La manifestación clínica más frecuente es la neumonía de comienzo insidioso y en su evolución natural tiende a la cavitación. El diagnóstico se realiza mediante su identificación en cultivo de muestras de tejido afectado. Los hemocultivos son positivos en el 50% de los inmunodeprimidos En el diagnóstico radiográfico, los hallazgos más comunes referidos en la literatura científica son el compromiso lobar y la cavitación. La particular evolución que experimentan los pacientes con síndrome de inmunodeficiencia adquirida y neumonía por R. equi, obliga a implementar esquemas terapéuticos basados en antimicrobianos con actividad bactericida intracelular, administrados inicialmente por vía intravenosa y durante un tiempo prolongado e incluso la cirugía. La infección por R. equi es una complicación infrecuente en pacientes con síndrome de inmunodeficiencia adquirida, pero con una elevada tasa de letalidad, por lo que debe ser sospechado en pacientes que presenten una infección respiratoria de curso inhabitual. El diagnóstico precoz, el tratamiento antimicrobiano combinado y prolongado y el inicio de la Terapia Antiretroviral de Gran Actividad en forma temprana pueden mejorar la evolución y el pronóstico de estos pacientes.

ABSTRACT Rhodococcus equi is an emergent microorganism associated to opportunistic infections in immune-compromised individuals, especially in patients infected with the human immunodeficiency virus. A search was carried out in the Virtual Library of Infomed; 215 scientific works were reviewed without limits of publication years and countries. From them, 55 were chosen. Rhodococcus equi is an intracellular pathogen that is able to grow and live inside the macrophages expressing the Mac-1 (CD11b/CC18) receptor in the surface and destroying them later. The most common clinical manifestation is insidious beginning pneumonia, tending to cavitation in its natural evolution. The diagnosis is made through identification in culture of affected tissues samples. Blood cultures are positive in 50 % of the immune-depressed people. At the radiographic diagnosis, the most common findings referred to in the scientific literature are lobar compromise and cavitation. The particular evolution of the patients with acquired immune-deficiency syndrome and pneumonia due to Rhodococcus equi forces the implementation of therapeutic schemes based on antimicrobials with intracellular bactericide activity, administered firstly intravenously and during a long time, and even to perform the surgery. Rhodococcus equi infection is an infrequent complication in patients with acquired immunodeficiency syndrome, but having a high lethality rate, therefore it should be suspected in patients presenting a respiratory infection of unusual curse. The precocious diagnosis, combined and prolonged antimicrobial treatment and early beginning of the highly active antiretroviral therapy could improve the evolution and prognosis of these patients.

Pathologic characteristics for the Rhodococcus equi infection in foals in Jeju / 대한수의학회지

From 1996 to 2014, 14 foals from nine farms in Jeju were diagnosed with a Rhodococcus equi infection. Clinically, most foals showed characteristic respiratory signs, including hyperthermia and dyspnea. The seasonal occurrence of R. equi infection in foals was higher in summer, such as June (eight foals; 57.1%) and July (four foals; 28.6%), than in the other seasons. The major cases of R. equi infections were observed among two-month-old (eight foals; 57.1%) and three-month-old (three foals; 21.4%) foals. Histopathologically, bronchopneumonia, abscess, and granulomatous pneumonia were the most prevalent lesions in the lungs of foals. Colonic ulcers and submucosal abscesses were found in a foal. Some foals showed granulomatous lymphadenitis and abscesses in the mesenteric and other lymph nodes. According to the polymerase chain reaction using 10 tissue samples of foals and nine R. equi isolates, the vapA gene was detected in 11/11 (100%) foals. Immunohistochemical staining using the anti-VapA monoclonal antibody was applied to detect the R. equi VapA antigen in the organs of foals. R. equi VapA antigens were demonstrated in most lungs and some mesenteric and hilar lymph nodes of 13 foals. Isolated virulent R. equi VapA bacteria showed high sensitivity to gentamicin, quinolones, rifampin, and vancomycin.

Rubber gloves biodegradation by a consortium, mixed culture and pure culture isolated from soil samples

Abstract An increasing production of natural rubber (NR) products has led to major challenges in waste management. In this study, the degradation of rubber latex gloves in a mineral salt medium (MSM) using a bacterial consortium, a mixed culture of the selected bacteria and a pure culture were studied. The highest 18% weight loss of the rubber gloves were detected after incubated with the mixed culture. The increased viable cell counts over incubation time indicated that cells used rubber gloves as sole carbon source leading to the degradation of the polymer. The growth behavior of NR-degrading bacteria on the latex gloves surface was investigated using the scanning electron microscope (SEM). The occurrence of the aldehyde groups in the degradation products was observed by Fourier Transform Infrared Spectroscopy analysis. Rhodococcus pyridinivorans strain F5 gave the highest weight loss of rubber gloves among the isolated strain and posses latex clearing protein encoded by lcp gene. The mixed culture of the selected strains showed the potential in degrading rubber within 30 days and is considered to be used efficiently for rubber product degradation. This is the first report to demonstrate a strong ability to degrade rubber by Rhodococcus pyridinivorans.

Characterization of Rhodococcus sp. A5wh isolated from a high altitude Andean lake to unravel the survival strategy under lithium stress / Caracterización de las estrategias seguidas por Rhodococcus sp. A5wh proveniente de laguna de altura en su adaptación a la presencia de litio

Lithium (Li) is widely distributed in nature and has several industrial applications. The largest reserves of Li (over 85%) are in the so-called "triangle of lithium" that includes the Salar de Atacama in Chile, Salar de Uyuni in Bolivia and Salar del Hombre Muerto in Argentina. Recently, the use of microorganisms in metal recovery such as copper has increased; however, there is little information about the recovery of lithium. The strain Rhodococcus sp. A5wh used in this work was previously isolated from Laguna Azul. The assays revealed that this strain was able to accumulate Li (39.52% of Li/g microbial cells in 180 min) and that it was able to grow in its presence up to 1 M. In order to understand the mechanisms implicated in Li tolerance, a proteomic approach was conducted. Comparative proteomic analyses of strain A5wh exposed and unexposed to Li reveal that 17 spots were differentially expressed. The identification of proteins was performed by MALDI-TOF/MS, and the obtained results showed that proteins involved in stress response, transcription, translations, and metabolism were expressed under Li stress. This knowledge constitutes the first proteomic approach to elucidate the strategy followed by Rhodococcus to adapt to Li.

El litio (Li) es un elemento químico con múltiples aplicaciones industriales. Es considerado uno de los minerales más ampliamente distribuidos en la naturaleza. Sus mayores reservas (más del 85%) se encuentran en el llamado «triángulo de litio¼: salar de Atacama, en Chile; salar de Uyuni, en Bolivia, y salar del Hombre Muerto, en Argentina. En los últimos años, el empleo de microorganismos en la recuperación de metales se ha visto incrementado; sin embargo, hay muy poca información sobre la recuperación de Li por esta vía. En este estudio se trabajó con Rhodococcus sp. A5wh, cepa aislada de Laguna Azul. Los ensayos revelaron que este microorganismo fue capaz de acumular Li (39,52% de Li/g de biomasa en 180 min) y de crecer en presencia de este metaloide hasta una concentración de 1 M. Para comprender los mecanismos implicados en la tolerancia al Li, se llevó a cabo el análisis proteómico comparativo de esta cepa expuesta o no expuesta al Li. Los resultados revelaron 17 spots expresados en forma diferencial. La identificación de las proteínas se realizó porMALDI-TOF/MS. Este estudio constituye el primer enfoque proteómico para dilucidar la estrategia seguida por Rhodococcus en su adaptación al estrés.

Pharmaceutical Care for Infant Patient with Rhodococcus equi Infection / 医药导报

Objective To provide reference for drug use in infant patients with Rhodococcus equi(R.equi) infection. Methods By participating in drug therapy for an infant patient with Rhodococcus equi infection,clinical pharmacist assisted physicians to develop treatment plan and provide reasonable pharmaceutical care. Results Therapeutic selection was improved through pharmaceutical care process. Conclusion Participation of clinical pharmacist can fully play their advantages in the field of drug efficacy,and improve the level of clinical treatment.

One case of acquired immunodeficiency syndrome complicated with Rhodococcus equi infection and review of the literatures / 中国感染控制杂志

Rhodococcus equi (R.equi) belongs to Rhodococcus spp.,and is a gram-positive bacterium.R.equi infection is a rare complication in advanced stage of patients with acquired immunodeficiency syndrome (AIDS).Diagnosis and treatment of one case of AIDS complicated with R.equi infection in a hospital was summarized,related literatures about AIDS complicated with R.equis infection published at home and abroad between January 2007 and January 2017 were reviewed,so as to improve clinicians' understanding on clinical characteristics of AIDS combined with R.equi infection,early diagnosis of the disease can be achieved,and at least 2 kinds of antibiotics are selected for anti-infective treatment,highly active antiretroviral therapy can be given as soon as possible,better clinical outcomes can be expected.

Response of Rhodococcus erythropolis strain IBBPo1 to toxic organic solvents

Abstract Recently, there has been a lot of interest in the utilization of rhodococci in the bioremediation of petroleum contaminated environments. This study investigates the response of Rhodococcus erythropolis IBBPo1 cells to 1% organic solvents (alkanes, aromatics). A combination of microbiology, biochemical, and molecular approaches were used to examine cell adaptation mechanisms likely to be pursued by this strain after 1% organic solvent exposure. R. erythropolis IBBPo1 was found to utilize 1% alkanes (cyclohexane, n-hexane, n-decane) and aromatics (toluene, styrene, ethylbenzene) as the sole carbon source. Modifications in cell viability, cell morphology, membrane permeability, lipid profile, carotenoid pigments profile and 16S rRNA gene were revealed in R. erythropolis IBBPo1 cells grown 1 and 24 h on minimal medium in the presence of 1% alkanes (cyclohexane, n-hexane, n-decane) and aromatics (toluene, styrene, ethylbenzene). Due to its environmental origin and its metabolic potential, R. erythropolis IBBPo1 is an excellent candidate for the bioremediation of soils contaminated with crude oils and other toxic compounds. Moreover, the carotenoid pigments produced by this nonpathogenic Gram-positive bacterium have a variety of other potential applications.

Biofilm formation by Rhodococcus equi and putative association with macrolide resistance / Formação de biofilme por Rhodococcus equi e possível associação com resistência a macrolídeos

Rhodococcus equi is a facultative intracellular pathogen, which cause severe pyogranulomatous pneumonia in foals and tuberculosis-like lesions in humans. Its ability to form biofilm was described in strains isolated from chronic diseases associated to treatment failures in humans. This study aimed to verify the biofilm formation by 113 R. equi isolated from equine samples (clinical and fecal) using two different methods (biofilm-culturing with and without additional glucose and epifluorescence microscopy). We also aimed to determine the efficacy of azithromycin, clarithromycin and erythromycin on R. equi in established biofilm. We found 80.5% (26/41) and 63% (58/72) biofilm-positive isolates, in fecal and clinical samples, respectively. The additional glucose increased the biofilm formation by R. equi fecal samples, but not by clinical samples. The antimicrobials tested herein were not able to eradicate R. equi in biofilm even at higher concentrations. This is the first study showing the biofilm formation by R. equi isolated from equine samples. Our findings indicate that R. equi biofilm-producers may be more resistant to the antimicrobials evaluated. Further studies are warranted to test this hypothesis...

Rhodococcus equi é um patógeno intracelular facultativo, o qual causa pneumonia piogranulosa severa em potros e lesões semelhantes à tuberculose em humanos. A sua capacidade de formar biofilme foi descrita em cepas humanas, isoladas a partir de doenças crônicas associadas a falhas de tratamento. Este estudo teve como objetivo verificar a formação de biofilme por 113 cepas de R. equi, isoladas a partir de amostras de equinos (clínicas e fecais), utilizando-se dois diferentes métodos (biofilme em cultura - com e sem adição de glicose - e microscopia de epifluorescência). Além disso, buscou-se determinar a eficácia da azitromicina, claritromicina e eritromicina sobre biofilme consolidado de R. equi. Verificou-se 80,5% (26/41) e 63% dos isolados (58/72) positivos para formação de biofilme, em amostras fecais e clínicas, respectivamente. A adição de glicose amentou a formação de biofilme em amostras fecais, mas não em amostras clínicas. Os antimicrobianos aqui testados não foram capazes de erradicar R. equi em biofilme consolidado, mesmo em concentrações elevadas. Este é o primeiro estudo a demonstrar a formação de biofilme por cepas de R. equi isoladas a partir de amostras de equinos. Os resultados indicam que os isolados de R. equi produtores de biofilme podem ser mais resistentes aos antimicrobianos avaliados. Estudos adicionais são necessários para testar essa hipótese...

Isolation of an aryloxyphenoxy propanoate (AOPP) herbicide-degrading strain Rhodococcus ruber JPL-2 and the cloning of a novel carboxylesterase gene (feh)

The strain JPL-2, capable of degrading fenoxaprop-P-ethyl (FE), was isolated from the soil of a wheat field and identified as Rhodococcus ruber. This strain could utilize FE as its sole carbon source and degrade 94.6% of 100 mg L−1 FE in 54 h. Strain JPL-2 could also degrade other aryloxyphenoxy propanoate (AOPP) herbicides. The initial step of the degradation pathway is to hydrolyze the carboxylic acid ester bond. A novel esterase gene feh, encoding the FE-hydrolyzing carboxylesterase (FeH) responsible for this initial step, was cloned from strain JPL-2. Its molecular mass was approximately 39 kDa, and the catalytic efficiency of FeH followed the order of FE > quizalofop-P-ethyl > clodinafop-propargyl > cyhalofop-butyl > fluazifop-P-butyl > haloxyfop-P-methyl > diclofop-methy, which indicated that the chain length of the alcohol moiety strongly affected the hydrolysis activity of the FeH toward AOPP herbicides.

Biodegradation of crude oil by individual bacterial strains and a mixed bacterial consortium

Three bacterial isolates identified as Alcanivorax borkumensis SK2, Rhodococcus erythropolis HS4 and Pseudomonas stutzeri SDM, based on 16S rRNA gene sequences, were isolated from crude oil enrichments of natural seawater. Single strains and four bacterial consortia designed by mixing the single bacterial cultures respectively in the following ratios: (Alcanivorax: Pseudomonas, 1:1), (Alcanivorax: Rhodococcus, 1:1), (Pseudomonas: Rhodococcus, 1:1), and (Alcanivorax: Pseudomonas: Rhodococcus, 1:1:1), were analyzed in order to evaluate their oil degrading capability. All experiments were carried out in microcosms systems containing seawater (with and without addition of inorganic nutrients) and crude oil (unique carbon source). Measures of total and live bacterial abundance, Card-FISH and quali-, quantitative analysis of hydrocarbons (GC-FID) were carried out in order to elucidate the co-operative action of mixed microbial populations in the process of biodegradation of crude oil. All data obtained confirmed the fundamental role of bacteria belonging to Alcanivorax genus in the degradation of linear hydrocarbons in oil polluted environments.

Pneumonia due to Rhodococcus equi in a non-Hodgkin's lymphoma patient: case report

The authors reported a lung infection by Rhodococcus equi in a 25 years-old male patient admitted to hospital with cough, dyspnea, fever, and previous diagnosis of pleural effusion. R. equi was isolated from pleural fluid and the patient acquired nosocomial infection by Acinetobacter baumannii, isolated from chest drain. The patient was treated with antibiotics. During hospitalization, he was diagnosed with non-Hodgkin lymphoma of precursor T-cell lymphoblastic lymphoma subtype in biopsy of pleura. After undergoing surgery for pulmonary decortication for drain empyema, the patient died due to septicemia(AU)

Los autores informan de una infección pulmonar por Rhodococcus equi en un paciente masculino de 25 años que fuera hospitalizado con tos seca, disnea, fiebre y diagnóstico previo de derrame pleural. R. equi se aisló del líquido pleural y el paciente adquiere una infección nosocomial con Acinetobacter baumannii aisladas de un drenaje torácico. El paciente recibió tratamiento con antibióticos y, durante la hospitalización, fue diagnosticado linfoma no Hodgkin subtipo de linfoma linfoblástico de precursoras de células T en la biopsia pleural. Después de la cirugía para decorticación pulmonar para la fuga de empiema, el paciente falleció debido a una septicemia(AU)

A Case of Recurrent Meningitis Caused by Rhodococcus species Successfully Treated with Antibiotic Treatment and Intrathecal Injection of Vancomycin through an Ommaya Reservoir

Human infection by Rhodococcus species is rare and mostly limited to immunocompromised hosts such as patients infected with the human immunodeficiency virus (HIV) or organ transplant recipients. The most common strain is R. equi, and the most common clinical presentation is pulmonary infection, reported in 80% of Rhodococcus spp. infections. The central nervous system is an uncommon infection site. We report a case of a patient with pneumonia, brain abscess, and recurrent meningitis caused by Rhodococcus spp. He initially presented with pneumonia with necrosis, which progressed to brain abscess and recurrent meningitis. Rhodococcus spp. was identified from the cerobrospinal fluid (CSF) collected during his fourth hospital admission. Despite prolonged treatment with appropriate antibiotics, meningitis recurred three times. Finally, in order to administer antibiotics directly into the CSF and bypass the blood-brain barrier, an Ommaya reservoir was inserted for administration of 90 days of intrathecal vancomycin and amikacin in conjunction with intravenous and oral antibiotics; the patient was finally cured with this treatment regimen.

Malacoplaquia pulmonar associada à imunodeficiência por HTLV-1 e HIV / Pulmonary malakoplakia associated with immunodeficiency by HTLV-1 and HIV

Malakoplakia is a rare chronic inflammatory disease often confused with neoplasia. In this paper we report two cases of pulmonary Malakoplakia, both with typical clinical diagnosis of tuberculosis and lung cancer. A patient with human T-lymphotropic virus type I (HTLV-1) and diagnosis of adult T-cell leukemia/lymphoma, and another patient with human immunodeficiency virus (HIV), which was treated for tuberculosis, but, after pulmonary lobectomy, was evidenced Rodococosis equi, progressed to death...

Malacoplaquia é uma rara doença inflamatória crônica muitas vezes confundida com neoplasia. Neste artigo, relatam-se dois casos de malacoplaquia pulmonar, ambos com quadro clínico sugestivo de tuberculose e neoplasia pulmonar. Uma paciente com vírus T-linfotrópico humano tipo I (HTLV-1) e diagnóstico de leucemia/linfoma de células T do adulto, e um paciente com vírus da imunodeficiência humana (HIV), tratado para tuberculose, mas após lobectomia pulmonar foi evidenciado Rodococose equi, evoluindo para óbito...