[Molecular characterization of Shiga toxin producing Escherichia coli isolated from 2 livestock establishments of Paraguay].
The objective of this study was to determine the carrying of STEC in Paraguayan bovines and to analyze the virulence profile and serotypes of these isolates. A total of 197 samples of bovine fecal samples and an average of 5 to 50 colonies from stx1/stx2 positive samples were studied. The stx1, stx2, saa, ehxA and eae genes were amplified by PCR. 84.8% of the cattle were carriers of STEC. The predominant virulence profiles were stx2 and stx2/saa/ehxA. The serotyping was performed by agglutination reactions for 60 selected isolates, resulting in isolation of serogroup O103, which could produce infections in humans. This wor...
Source: Revista Argentina de Microbiologia - October 23, 2019 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

[Neisseria meningitidis isolated from patients in men who have sex with men].
Authors: García SD, Sorhuet-Pereira C, Perazzi BE, Losada ME, Cabellos Astorga G, Casco RH, Vay CA, Mollerach ME, Famiglietti ÁMR Abstract During the periods 2000-2004 and 2014-2015, Neisseria meningitidis was investigated in men who have sex with men, 1143 and 544 respectively, who consulted in the sexually-transmitted disease program. Prevalence, serogroup distribution and susceptibility to antibiotics were determined. Pharyngeal, rectal and urethral swabs were cultivated on selective Thayer-Martin modified medium. The identification was performed by biochemical tests and mass spectrometry by MALDI-...
Source: Revista Argentina de Microbiologia - October 21, 2019 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

Production of a latex agglutination reagent for the rapid diagnosis of cryptococcal meningitis.
Authors: Trovero AC, Mazza M, Rogé A, Rivas MC, Bordagorría X, Bruno S, Davel G Abstract Cryptococcosis is a fungal disease affecting more than one million people per year worldwide. Its main etiological agents are Cryptococcus neoformans species complex and Cryptococcus gattii species complex. Cryptococcal meningitis (CM) is considered an AIDS-defining condition. Rapid diagnosis by cryptococcal antigen assays, either the latex agglutination test (LA) or the lateral flow assay, is key to decreasing mortality due to cryptococcal disease. The aim of the study was to develop a latex agglutination reagent...
Source: Revista Argentina de Microbiologia - October 2, 2019 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

[Profile of antimicrobial resistance in isolates of Staphylococcus spp. obtained from bovine milk in Colombia].
Authors: Jiménez Velásquez SDC, Torres Higuera LD, Parra Arango JL, Rodríguez Bautista JL, García Castro FE, Patiño Burbano RE Abstract Staphylococcus spp. is one of the pathogens that cause bovine mastitis and may present multiple resistance to different antimicrobial groups. The aim of this study was to phenotypically identify Staphylococcus spp. isolates obtained from bovine milk and to characterize their antimicrobial resistance profile. The 101 strains were classified by phenotypic tests, their resistance to oxacillin, cefoxitin, penicillin, ampicillin, tetracycline, kanamyci...
Source: Revista Argentina de Microbiologia - September 22, 2019 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

[And we've reached the 50th  Anniversary of Revista Argentina de Microbiología].
[And we've reached the 50th Anniversary of Revista Argentina de Microbiología]. Rev Argent Microbiol. 2019 Jul - Sep;51(3):189-190 Authors: Di Conza JA, Predari SC PMID: 31514958 [PubMed - in process] (Source: Revista Argentina de Microbiologia)
Source: Revista Argentina de Microbiologia - September 15, 2019 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

Microbiological contaminations of laboratory mice and rats in conventional facilities in Argentina.
Authors: Carriquiriborde M, Milocco S, Laborde JM, Gentil F, Maschi F, Principi G, Rogers E, Cagliada MDP, Ayala MA, Carbone C Abstract Routine microbiological monitoring of rodent colonies in animal facilities is essential to evaluate the health status of the animals used in research studies. In the present study, animals were examined for the presence of selected microbial infections. In order to determine the contamination rates of mice and rats in Argentina, animals from 102 conventional facilities were monitored from 2012 to 2016. The most frequent bacteria isolated were Pseudomonas aeruginosa and Proteus spp....
Source: Revista Argentina de Microbiologia - September 9, 2019 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

Protective effect on wood by metabolic extracts from plant growth-promoting rhizobacteria against decay fungi.
Authors: García-Ortiz V, Hernández-Soberano C, Martínez-Pacheco M, Ambriz-Parra E, Velázquez Becerra C PMID: 31378516 [PubMed - as supplied by publisher] (Source: Revista Argentina de Microbiologia)
Source: Revista Argentina de Microbiologia - August 6, 2019 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

[Morphological and molecular differentiation by high resolution melting curves (HRMA) and sequencing of the Trichophyton mentagrophytes complex in human strains in Valpara íso, Chile].
In conclusion, no reliable morphophysiological patterns were established to differentiate between the species of the complex. Molecularly, all the strains studied were classified as T. interdigitale. PMID: 31350016 [PubMed - as supplied by publisher] (Source: Revista Argentina de Microbiologia)
Source: Revista Argentina de Microbiologia - July 28, 2019 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

[Isolation of enterocin-producing Enterococcus hirae strains from the intestinal content of the Patagonian mussel (Mytilus edulis platensis)].
Authors: Vallejo M, Parada RB, Marguet ER Abstract Two bacteriocin-producing lactic acid bacterial strains were isolated from the intestinal content of the Patagonian mussel and characterized by phenotypic and molecular tests. The isolates were identified as Enterococcus hirae and named E. hirae 463Me and 471Me. The presence of the enterocin P gene was identified in both strains by PCR techniques, while enterocin hiracin JM79 was detected only in the 471Me strain. Both strains were sensitive to clinically important antibiotics and among the virulence traits investigated by PCR amplification, only cylLl and cylLs co...
Source: Revista Argentina de Microbiologia - July 21, 2019 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

Progression of the predatory activity of an Argentine strain of Arthrobotrys oligospora (Helotiales: Orbiliaceae) on Panagrellus redivivus (Rhabditidae: Panagrolaimidae).
Authors: Maestro M, Sauka DH PMID: 31272726 [PubMed - as supplied by publisher] (Source: Revista Argentina de Microbiologia)
Source: Revista Argentina de Microbiologia - July 7, 2019 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

Arbuscular mycorrhizal fungi in heavy metal highly polluted soil in the Riachuelo river basin.
Authors: Colombo RP, Benavidez ME, Fernandez Bidondo L, Silvani VA, Bompadre MJ, Statello M, Scorza MV, Scotti A, Godeas AM Abstract The Riachuelo river basin (RRB) is considered one of the most polluted environments in the world. Knowledge of arbuscular mycorrhizal fungi (AMF) adapted to this extremely polluted environment is important for the establishment of future soil restoration projects. This work aims to make a first list of AMF species present on the RRB. Soil and root samples were randomly taken in an area of approximately 1500m2, mycorrhization percentages were evaluated. AMF species were detected by mol...
Source: Revista Argentina de Microbiologia - July 7, 2019 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

[High seroprevalence of Neospora caninum in dogs with clinical suspicion of neosporosis in Montevideo, Uruguay].
Authors: Satragno D, Pavón-Rocha AJ, Rábago-Castro JL, la Cruz-Hernández NI PMID: 31272728 [PubMed - as supplied by publisher] (Source: Revista Argentina de Microbiologia)
Source: Revista Argentina de Microbiologia - July 7, 2019 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

An Stx-EAEC O59:NM[H19] strain isolated from a hemolytic uremic syndrome case in Argentina.
In this study, we report an HUS case associated with an O59:NM[H19] strain, harboring stx2a, iha, lpfAO26, lpfAO113 genes associated with STEC, and aatA, aap, pic, sigA, agg4A genes associated with enteroaggregative E. coli (EAEC), named Stx-EAEC. The strain showed low toxicity on Vero cells, and was resistant to streptomycin and trimethoprim/sulfonamides. The child carried the bacteria for more than 100 days. Since the large outbreak associated with Stx-EAEC O104:H4, many strains with similar profiles have been described. In Germany, an O59:NM[H19] strain, with comparable characteristics to the Argentine strain, was isola...
Source: Revista Argentina de Microbiologia - July 4, 2019 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

Fungemia following Saccharomyces cerevisiae var. boulardii probiotic treatment in an elderly patient.
We report a case of fungemia in a patient suffering from Clostridiumdifficile-associated diarrhea and treated with metronidazole and a probiotic containing S. cerevisiae var. boulardii. The yeasts isolated from the blood culture and capsules were identified by MALDI-TOF MS and API ID 32 C as S. cerevisiae, and showed the same appearance and color on CHROMAgar Candida. Treatment with fluconazole 400mg/day was initiated and the probiotic was stopped. The patient was discharged from hospital in good condition and was referred to a rehabilitation center. We suggest that the potential benefit of S. cerevisiae var. boulardii sho...
Source: Revista Argentina de Microbiologia - July 4, 2019 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

[Epidemiological data description of pediatric patients with diarrhea by Aeromonas spp. and the antibiotic susceptibility of this agent].
Authors: Del Valle de Toro A, Santos-Pérez JL, Navarro-Marí JM, Gutiérrez-Fernández J Abstract The aim of our study was to describe the epidemiological features of pediatric patients with diarrhea caused by Aeromonas spp. and to study the antibiotic susceptibility of this agent during a seven-year period. Aeromonas caviae was identified in 93 stool samples from 52.2% males and 85.6% patients younger than 36 months. The season with the lowest number of isolates was winter (14.4%). Co-infection with other diarrheagenic microorganisms was observed in 31.1% of the cases. The largest number o...
Source: Revista Argentina de Microbiologia - July 1, 2019 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

Diversity of Achromobacter species recovered from patients with cystic fibrosis, in Argentina.
In conclusion, prompt and accurate identification tools were necessary to determine that different Achromobacter species may colonize/infect the airways of patients with CF. Moreover, antimicrobial therapy should be administered based on the susceptibility profile of individual Achromobacter sp. isolates. PMID: 31253503 [PubMed - as supplied by publisher] (Source: Revista Argentina de Microbiologia)
Source: Revista Argentina de Microbiologia - July 1, 2019 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

[Cross-resistance between isoniazid and ethionamide and its strong association with mutation C-15T in Mycobacterium tuberculosis isolates from Peru].
The objective of this study was to determine the cross-resistance between both drugs in Mycobacterium tuberculosis isolates from a hospital with high incidence of tuberculosis in Lima, Peru. The frequency of mutations to isoniazid in the katG gene and the inhA promoter region was identified by the Genotype MTBDRplus v2.0 molecular test. The gold standard Agar Proportion method (APM) allowed todetect resistance to isoniazid and ethionamide. Of 107 isoniazid-resistant isolates (54 multidrug-resistant isolates identified by the Genotype MTBDRplus test, 45.8% (49/107) were also resistant to ethionamide by the APM. Mutations we...
Source: Revista Argentina de Microbiologia - July 1, 2019 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

[Scedosporium spp. osteomyelitis: A case report].
We present here a case of a 54- year- old male patient with a diagnosis of chronic bacterial osteomyelitis due to an aquatic accident and exposed fracture of tibia-fibula of both members, which was treated with broad-spectrum antibiotics for 120 days. Eight months after the onset of the disease, Scedosporium spp. was isolated from the collection of one of the affected member, which was treated with voriconazole in combination with terbinafine. PMID: 31204057 [PubMed - as supplied by publisher] (Source: Revista Argentina de Microbiologia)
Source: Revista Argentina de Microbiologia - June 19, 2019 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

Moringa straw as cellulase production inducer and cellulolytic fungi source.
Authors: Vázquez-Montoya EL, Castro-Ochoa LD, Maldonado-Mendoza IE, Luna-Suárez S, Castro-Martínez C Abstract Currently, the valorization of agroindustrial waste is of great interest. Moringa oleifera is a multipurpose tree whose softwood residues could be used as raw material for low-cost cellulase production. The aim of this study was to isolate, identify, and characterize microorganisms with cellulolytic activity in different carbon sources. We isolated and purified 42 microorganisms from M. oleifera biomass. Fungi presenting the largest hydrolytic halos in carboxymethylcellulose as a substr...
Source: Revista Argentina de Microbiologia - June 19, 2019 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

[Development of sequence characterized amplified region markers for identification of Azospirillum brasilense Az39].
Authors: Coniglio A, López G, Gualpa J, Molina R, Rosas S, Puente M, Mora V, Cassán F Abstract Azospirillum brasilense Az39 has been used since more than 30 years by several companies in South America for biofertilizers production. This strain may promote plants growth and development, as well as the ability of inoculated plants to tolerate environmental stresses, which determines an increase in the productivity under field conditions. At present, there are no protocols in Argentina to confirm the identity of Az39 in commercial products; however, such biofertilizers are formulated almost exclusively w...
Source: Revista Argentina de Microbiologia - June 17, 2019 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

Tolerance of dark septate endophytic fungi (DSE) to agrochemicals in vitro.
Authors: Spagnoletti FN, Chiocchio VM Abstract Dark septate endophytes (DSE) are a heterogeneous group of fungi, mostly belonging to the Phylum Ascomycota, that are involved in a mutualistic symbiosis with plant roots. The aim of this study is to evaluate the behavior of two strains of DSE isolated from wheat roots of two cropping areas in the province of Buenos Aires, Argentina, against some agrochemicals. Of all the isolates obtained, two strains were identified as Alternaria alternata and Cochliobolus sp. These DSE were found to be tolerant to glyphosate, carbendazim and cypermethrin when evaluated at the recomm...
Source: Revista Argentina de Microbiologia - June 11, 2019 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

[Presentation of the National Network for Microbiological Identification by Mass Spectrometry website. Guide for the interpretation of MALDI-TOF MS results].
Authors: Rocca MF, Almuzara M, Barberis C, Vay C, Viñes P, Prieto M PMID: 31178239 [PubMed - as supplied by publisher] (Source: Revista Argentina de Microbiologia)
Source: Revista Argentina de Microbiologia - June 11, 2019 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

[Effect of glyphosate on microbiota, soil quality and biofortified bean crop in Codazzi, department of Cesar, Colombia].
In conclusion, in plots with high weed pressure by Cyperus rotundus, the use of mulch is recommended as an alternative to maintain bean productivity over time; by offering protection against the effect of the herbicide on both the root system of the plant and the soil microbiota of the biofortified bean crop. PMID: 31153682 [PubMed - as supplied by publisher] (Source: Revista Argentina de Microbiologia)
Source: Revista Argentina de Microbiologia - June 4, 2019 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

First report of a clinical isolate of blaOXA-48- carbapenemase producing Raoultella ornithinolytica in South America.
Authors: Reyes JA, Villavicencio F, Villacís JE, Pavón E, Campoverde N, Espinel M, Núñez B, Trueba G PMID: 31133355 [PubMed - as supplied by publisher] (Source: Revista Argentina de Microbiologia)
Source: Revista Argentina de Microbiologia - May 30, 2019 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

[Reportable mycoses: Utopia or reality. A forgotten matter still unresolved].
Authors: Fernandez NB, Davel G PMID: 31097349 [PubMed - as supplied by publisher] (Source: Revista Argentina de Microbiologia)
Source: Revista Argentina de Microbiologia - May 18, 2019 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

Five-assay microbiological system for the screening of antibiotic residues.
Authors: Tumini M, Nagel OG, Althaus RL Abstract A novel microbiological system in microtiter plates consisting of five bioassays is presented for the detection and classification of antibiotic residues in milk. The bioassays were optimized for the detection of beta-lactams (Bioassay B: Geobacillus stearothermophilus), macrolides (Bioassay M: Bacillus megaterium with fusidic acid), tetracyclines (Bioassay T: B. megaterium with chloramphenicol), quinolones (Bioassay Q: Bacillus licheniformis) and sulfamides (Bioassay QS: B. licheniformis with trimethoprim) at levels near the maximum residue limits (MRL). The respons...
Source: Revista Argentina de Microbiologia - May 7, 2019 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

Comparison of three molecular subtyping techniques for Listeria monocytogenes.
Authors: Londero A, Costa M, Sucari A, Leotta G Abstract Listeria monocytogenes is a foodborne pathogen. The recent alert for L. monocytogenes in vegetables from Argentina warns about the importance of reinforcing its isolation, characterization and subtyping in food, clinical and environmental samples. The aim of the present study was to compare the discriminatory power of enterobacterial repetitive intergenic consensus polymerase chain reaction (ERIC-PCR), automated ribotyping and pulsed-field gel electrophoresis (PFGE) to subtype strains of L. monocytogenes isolated from Argentine meat and environmental samples....
Source: Revista Argentina de Microbiologia - April 28, 2019 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

Experimental infection of sheep with Bovine leukemia virus (BLV): Minimum dose of BLV-FLK cells and cell-free BLV and neutralization activity of natural antibodies.
In this report, we aimed to determine the minimum amount of FLK-BLV cells or cell-free supernatant containing BLV needed to produce infection in sheep. We also evaluated the amount of antibodies obtained from a naturally-infected cow required to neutralize this infection. We observed that both sheep experimentally inoculated with 5000 FLK-BLV cells became infected, as well as one of the sheep receiving 500 FLK-BLV cells. None of the animals inoculated with 50 FLK-BLV cells showed evidence of infection. The cell-free FLK-BLV supernatant proved to be infective in sheep up to a 1:1000 dilution. Specific BLV antibodies showed ...
Source: Revista Argentina de Microbiologia - April 28, 2019 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

Seroprevalence of leptospirosis in human groups at risk due to environmental, labor or social conditions.
Authors: Meny P, Menéndez C, Ashfield N, Quintero J, Rios C, Iglesias T, Schelotto F, Varela G Abstract Leptospirosis is important in Uruguay due to the economic loss caused by the diseases of production animals, mainly bovines, and also due to frequent human infection. We decided to study anti-Leptospira antibodies in the sera of dairy workers, rice laborers, veterinarians, suburban slum dwellers and garbage recyclers. Our aims were to estimate the seroprevalence of infection by Leptospira spp. in these people at risk, the relative importance of the known risk factors associated with infection, and the impa...
Source: Revista Argentina de Microbiologia - April 15, 2019 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

Carbon-substrate utilization profiles by Cladorrhinum (Ascomycota).
Authors: Barrera VA, Martin ME, Aulicino M, Martínez S, Chiessa G, Saparrat MCN, Gasoni AL Abstract Fungi from the genus Cladorrhinum (Ascomycota) are promising agents in the biocontrol of phytopathogens, in the promotion of plant growth, and in the production of enzymes with technological application. We analyzed comparatively the ability of 5 native strains of Cladorrhinum samala and Cladorrhinum bulbillosum with reference strains belonging to the same genus. We used 95 individual carbon sources available in microplates from the Biolog® FF system. Although most of the strains mainly used soluble carboh...
Source: Revista Argentina de Microbiologia - April 15, 2019 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

[Detection of Human T lymphotropic virus 1 (HTLV-1) Cosmopolitan subtype Transcontinental subgroup (Aa) and HTLV-2 subtype b in blood donors of Corrientes].
Authors: Borda MA, Svibel GR, Biglione MM, Berini CA Abstract A molecular epidemiological study was conducted in a population of 9422 blood donors in the province of Corrientes, Northeastern Argentina, to determine the prevalence of Human T-cell lymphotropic virus types 1 and 2 (HTLV-1/2), the phylogenetic identification of HTLV-1 and 2 subtypes/subgroups and perform a mutation analysis. Based on the results obtained, it was shown that both HTLV-1 and HTLV-2 are circulating in a low-risk population of Corrientes, although with a similar prevalence to that of non-endemic areas. Phylogenetic studies identified the HT...
Source: Revista Argentina de Microbiologia - April 4, 2019 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

[Spotted fever in Argentina. Description of two clinical cases].
Authors: Armitano RI, Guillemi E, Escalada V, Govedic F, Lopez JL, Farber M, Borras P, Prieto M Abstract Rickettsioses are zoonotic tick-borne diseases. In Argentina, there are two epidemiological scenarios: jungle of Salta and Jujuy, involving vectors from the "Amblyomma cajennense Complex" (A. sculptum, and A. toneliae) and Rickettsia rickettsii as the main etiological agent; and the second scene to Delta del Rio Paraná and Samborombón Bay, where Amblyomma triste acts as a vector; and the provinces of Córdoba, La Rioja, San Luis and La Pampa where Amblyomma tigrinum is the vector. I...
Source: Revista Argentina de Microbiologia - April 1, 2019 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

[What can we do to prevent multidrug-resistance?]
Authors: Nastro M PMID: 30904052 [PubMed - in process] (Source: Revista Argentina de Microbiologia)
Source: Revista Argentina de Microbiologia - March 26, 2019 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

Correlation between ammonia-oxidizing microorganisms and environmental factors during cattle manure composting.
Authors: Sun Y, Zhu L, Xu X, Meng Q, Men M, Xu B, Deng L Abstract Cattle manure composting was performed in an aerated vessel. Community structure and diversity of ammonia-oxidizing bacteria (AOB) and ammonia-oxidizing archaea (AOA) were investigated using polymerase chain reaction and denaturing gradient gel electrophoresis (PCR-DGGE) techniques targeting the ammonia monooxygenase alpha subunit (amoA) gene and the correlation between AOB and AOA communities and environmental factors was explored. Thirteen (13) AOB sequences were obtained, which were closely related to Nitrosomonas spp., Nitrosomonas eutropha, and ...
Source: Revista Argentina de Microbiologia - March 26, 2019 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

Weissella paramesenteroides encapsulation and its application in the use of fish waste.
Authors: Libonatti C, Agüeria D, García C, Basualdo M Abstract The goal of the present study was to evaluate the encapsulation of Weissella paramesenteroides, isolated from bee bread, as a technological tool for its use in biological fish silage. The pH decrease in fish silages using the bacteria encapsulated and in a non-encapsulated form was compared. W. paramesenteroides showed a good performance in the development of biological fish silage. The alginate encapsulation method showed an encapsulation efficacy of 85% and provides a reliable technological application. PMID: 30905352 [PubMed - in proc...
Source: Revista Argentina de Microbiologia - March 26, 2019 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

The bZIP transcription factor Afap1 mediates the oxidative stress response and aflatoxin biosynthesis in Aspergillus flavus.
Authors: Guan X, Zhao Y, Liu X, Shang B, Xing F, Zhou L, Wang Y, Zhang C, Bhatnagar D, Liu Y Abstract Aflatoxin is a carcinogenic secondary metabolite produced mainly by Aspergillus flavus and Aspergillus parasiticus, which can seriously endanger the health of humans and animals. Oxidative stress is a common defense response, and it is known that reactive oxygen species (ROS) can induce the synthesis of a series of secondary metabolites, including aflatoxin. By using mutants lacking the afap 1 gene, the role of afap1 gene in oxidative stress and aflatoxin synthesis was assessed. The growth of the mutant strains was...
Source: Revista Argentina de Microbiologia - March 26, 2019 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

[Food poisoning outbreak in a kindergarten in the Province of Buenos Aires, Argentina].
Authors: Manfredi EA, Rivas M Abstract On November 27, 2008, a foodborne disease outbreak associated with the consumption of chicken salad occurred in a kindergarten in the District of Hurlingham, Province of Buenos Aires. Thirty-seven children and 10 adults with gastrointestinal symptoms were affected. Five children were hospitalized with signs of dehydration, one of them requiring intensive care. Staphylococcus aureus subsp. aureus was isolated from the mentioned food in 4 out of 5 stool specimens from the patients, and in 3 out of 5 food handlers (nose of food handler #1, hands of food handlers #2 and 3). The is...
Source: Revista Argentina de Microbiologia - March 21, 2019 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

In vitro effect of the crude extract of a potato common scab streptomycete in Sinaloa, Mexico.
This study reports that Streptomyces sp. V2 has a toxigenic region (TR) that is associated with the thaxtomin gene cluster. PMID: 30799233 [PubMed - as supplied by publisher] (Source: Revista Argentina de Microbiologia)
Source: Revista Argentina de Microbiologia - February 28, 2019 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

[Corynebacterium pseudotuberculosis biovar ovis: Evaluation of antibiotics susceptibility in vitro].
Authors: Gallardo AA, Toledo RA, González Pasayo RA, Azevedo V, Robles C, Paolicchi FA, Estevao Belchior SG Abstract The aims of this work were to study the antibiotic susceptibility in Corynebacterium pseudotuberculosis isolated from small ruminants and to determine the presence of integrons that contain resistance genes. Fifteen isolates of different sources were analysed using the diffusion and the dilution methods. When the diffusion method was performed, amoxicillin-clavulanic, ampicillin, cefotaxime, cefoxitin, ciprofloxacin, chloramphenicol, erythromycin, streptomycin, gentamicin, imipenem, kanamycin,...
Source: Revista Argentina de Microbiologia - February 26, 2019 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

Identification of an Argentinean isolate of Spodoptera frugiperda granulovirus.
Authors: Pidre ML, Sabalette KB, Romanowski V, Ferrelli ML Abstract The fall armyworm, Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae), is an important maize pest. Due to the environmental impact and emergence of resistance caused by chemical pesticides and transgenic events, the use of baculoviruses becomes a safe and useful alternative for its control in integrated pest management strategies. Here we report the identification of a novel isolate of a granulovirus of S. frugiperda native to the central region of Argentina, named SfGV ARG. We observed that larvae infected with SfGV ARG showed a yellowish...
Source: Revista Argentina de Microbiologia - February 25, 2019 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

[Synthesis and regulation of flavor compounds derived from brewing yeast: fusel alcohols].
Authors: Loviso CL, Libkind D Abstract Among the main beer components, fusel alcohols are important because of their influence on the flavor of the final product, and therefore on its quality. During the production process, these compounds are generated by yeasts through the metabolism of amino acids. The yeasts, fermentation conditions and wort composition affect fusel alcohols profiles and their concentrations. In this review, we provide detailed information about the enzymes involved in fusel alcohols formation and their regulation. Moreover, we describe how the type of yeast used, the fermentation temperature a...
Source: Revista Argentina de Microbiologia - February 6, 2019 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

[Effects of the culture medium and the methodology applied on the biofilm formation of 2diarrheagenic Escherichia coli strains].
Authors: Cáceres ME, Etcheverría AI, Padola NL Abstract The ability to form biofilms of pathogenic microorganisms in a wide variety of environments, surfaces and conditions constitute an important risk, both for the food industry and for public health. The aim of this work was to evaluate and to compare the effects of the methodology applied and the culture medium used on the ability of a non-O157 verotoxigenic Escherichia coli strain and an enteropathogenic strain to form biofilm on polystyrene surface. Two methodological variants were tested in static culture and culture mediums with different compo...
Source: Revista Argentina de Microbiologia - January 24, 2019 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

RNA-seq analysis of the response of plant-pathogenic oomycete Phytophthora parasitica to the fungicide dimethomorph.
Authors: Hao K, Lin B, Nian F, Gao X, Wei Z, Luo G, Lu Y, Lan M, Yang J, Wu G Abstract Phytophthora parasitica is an important oomycete that causes disease in a variety of plants, dimethomorph fungicides being specific for oomycetes. The aim of this study was to use RNA-seq to rapidly discover the mechanism by which dimethomorph acts in the treatment of P. parasitica. We found that the expression of 832 genes changed significantly after the dimethomorph treatment, including 365 up-regulated genes and 467 down-regulated genes. According to the Gene Ontology (GO) enrichment analysis, pathway enrichment and verificati...
Source: Revista Argentina de Microbiologia - January 24, 2019 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

Endophytic microorganisms Agrobacterium tumefaciens 6N2 and Meyerozyma guilliermondii 6N serve as models for the study of microbial interactions in colony biofilms.
Authors: Bertini EV, Leguina ACDV, Castellanos de Figueroa LI, Nieto-Peñalver CG PMID: 30651186 [PubMed - as supplied by publisher] (Source: Revista Argentina de Microbiologia)
Source: Revista Argentina de Microbiologia - January 19, 2019 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

Genetic diversity of Mycoplasma hyopneumoniae in Mendoza province.
Authors: Sosa C, Blois A, Ibáñez F, Tamiozzo P Abstract In Argentina, enzootic pneumonia (EP) is highly prevalent and different genetic types of Mycoplasma hyopneumoniae have been identified. However, there is a lack of information about prevalence and other epidemiological aspects of EP in Mendoza province. A multiple Locus variable-number tandem repeat analysis (MLVA) targeting P97 R1, P97 R1A and P146 R3 loci was used to assess the genetic diversity of M. hyopneumoniae from clinical specimens recovered from pigs from five herds located in different districts of Mendoza province. M. hyopneumoniae co...
Source: Revista Argentina de Microbiologia - January 19, 2019 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

Yeast diversity in Vitis non-vinifera ecosystems.
Authors: Raymond Eder ML, Rosa AL Abstract The surface of grapes lodges a complex community of yeast species responsible for spontaneous alcoholic fermentation. The study of indigenous Saccharomyces and "non-Saccharomyces" yeasts during grape must fermentation constitutes a major research area in microbial enology. Although there are detailed studies on the microbiota of Vitis vinifera L. grapes, little is known about the diversity of yeast communities present in non-vinifera Vitis ecosystems (i.e., grapes and spontaneously fermenting grape musts). Potentially scientific and/or enological valuable yeast s...
Source: Revista Argentina de Microbiologia - January 16, 2019 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

[Detection of serovars of Salmonella in artificially reared calves in Mar y Sierras Dairy Basin, Argentina].
In conclusion, 11 Salmonella serovars were detected in one out of 3dairy farms in Mar and Sierras Dairy Basin, and not only were these serovars associated with diarrhea signs including the presence of mucus in feces, but they were also more prevalent among calves aged up to 21 days. PMID: 30638637 [PubMed - as supplied by publisher] (Source: Revista Argentina de Microbiologia)
Source: Revista Argentina de Microbiologia - January 16, 2019 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

Clinical and microbiological characteristics of community-acquired pneumonia associated with Streptococcus pneumoniae in adult patients in Mexico.
In conclusion, head trauma was the most common comorbidity in the CAP group. The most prevalent serotype was 19A. Decreased susceptibility to most antimicrobials tested was observed. PMID: 30635204 [PubMed - as supplied by publisher] (Source: Revista Argentina de Microbiologia)
Source: Revista Argentina de Microbiologia - January 14, 2019 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

[Electronic cardiovascular device-associated to infective endocarditis caused by Mycobacterium mageritense].
We describe a case of endocarditis caused by Mycobacterium mageritense in a patient with an autologous pericardial patch and a pressure catheter in the left auricle. The bacterial species was identified as Mycobacterium mageritense by mass spectrometry (MALDI-TOF MS), score 2.3, and confirmed by 16S rRNA analysis with 99.8 and 100% agreement, respectively. PMID: 30591316 [PubMed - as supplied by publisher] (Source: Revista Argentina de Microbiologia)
Source: Revista Argentina de Microbiologia - December 30, 2018 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research

National production of certified reference fungal cultures.
Authors: Davel GO, Mazza M, Refojo N, Taverna CG, Rivas MC, Fernández J, Vivot ME, Mazza MG, Mastromónaco GM, Bueno NS, Molina V, Brero ML, Kornblit F Abstract Reference fungal cultures (RFCs) are essential for the internal quality control of laboratories. The production of these cultures requires standardized procedures (IRAM 14950:2016 and ISO 17034:2016 standards) carried out by a recognized and accredited laboratory. The aim of this work was to produce RFC in paper disks of autochthonous strains, characterized by two, homogeneous and stable reference methods traceable at species level. RFC were pr...
Source: Revista Argentina de Microbiologia - December 30, 2018 Category: Microbiology Tags: Rev Argent Microbiol Source Type: research