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FBackground. Stenotrophomonas are ubiquitous gram-negative bacteria, which can survive in a wide range of environments. They can use many substances for their growth and are known to be intrinsically resistant to many antimicrobial agents. They have been tested for biotechnological applications, bioremediation, and production of antimicrobial agents. Method. Stenotrophomonas sp. Pemsol was isolated from a crude oil contaminated soil. The capability of this isolate to tolerate and degrade polycyclic aromatic hydrocarbons (PAH) such as anthraquinone, biphenyl, naphthalene, phenanthrene, phenanthridine, and xylene was evaluated in Bushnell Hass medium containing PAHs as the sole carbon sources. The metabolites formed after 30-day degradation of naphthalene by Pemsol were analyzed using Fourier Transform Infra-red Spectroscopic (FTIR), Ultra-Performance Liquid Chromatography-Mass Spectrometry (UPLC-MS) and Gas Chromatography-Mass Spectrometry (GC-MS). The genome of Pemsol was also sequenced and analyzed. Results. Anthraquinone, biphenyl, naphthalene, phenanthrene, and phenanthridine except xylene can be used as sole carbon sources for Pemsol's growth in Bushnell Hass medium. The degradation of naphthalene at a concentration of 1 mg/mL within 30 days was tested. A newly formed catechol peak and the disappearance of naphthalene peak detected on the UPLC-MS, and GC-MS analyses spectra respectively confirmed the complete degradation of naphthalene. Pemsol does not produce biosurfactant and neither bio-emulsify PAHs. The whole genome was sequenced and assembled into one scaffold with a length of 4,373,402 bp. A total of 145 genes involved in the degradation of PAHs were found in its genome, some of which are Pemsol-specific as compared with other 11 Stenotrophomonas genomes. Most specific genes are located on the genomic islands. Stenotrophomonas sp. Pemsol's possession of few genes that are associated with bio-emulsification gives the genetic basis for its inability to bio-emulsify PAH. A possible degradation pathway for naphthalene in Pemsol was proposed following the analysis of Pemsol's genome. ANI and GGDH analysis indicated that Pemsol is likely a new species of Stenotrophomonas. It is the first report on a complete genome sequence analysis of a PAH-degrading Stenotrophomonas. Stenotrophomonas sp. Pemsol possesses features that make it a good bacterium for genetic engineering and will be an excellent tool for the remediation of crude oil or PAH-contaminated soil. [ABSTRACT FROM AUTHOR]

The genus Aeromonas are widely distributed in aquatic ecosystems are Gram-negative rods, oxidase-positive, and glucose-fermenting, considered emerging pathogens in humans. Aeromonas belongs to the fish microbiota, these microorganisms have a diversity of virulence factors responsible for a variety of infections in humans mainly gastrointestinal diseases. The presence of Aeromonas in products intended for consumption with high commercial demand such as tilapia generates sanitary concern due to the pathogenic potential of this bacteria. In this context, identification of virulence genes in strains of Aeromonas isolated in Oreochromis spp. intended for human consumption in Reynosa, Tamaulipas, Mexico is important due to the lack of molecular studies in this geographical area. In the present study the pathogenic potential of 15 strains of Aeromonas (A. veronii, A. hydrophila and A. schubertii) from Oreochromis spp. for human consumption were analyzed. Through PCR six virulence genes were analyzed (alt, ast, aerA, hlyA, gcat and stx1) and the strains used as control were: Aeromonas hydrophila subsp. hydrophila ATCC 7966, Aeromonas caviae 429865 INP, Escherichia coli O157: H7 and Escherichia coli K12. El 100 % (n = 15) of the strains harbored at least one virulence gene, aerA gene was detected in 86.66 % of the analyzed strains, while ast and stx1 genes were not identified. Moreover, Aeromonas strains had associated genes in the same strain: aerA / gcat, alt / aerA, alt / aerA / gcat / hlyA and alt / aerA / gcat, of which aerA / gcat were observed mostly in A. veronii, while A. hydrophila had the highest associations. These findings indicate that the strains of Aeromonas isolated in Oreochromis spp. have the potential to cause human diseases, and therefore, this species used as food, could be a vehicle for infections caused by Aeromonas. It also allows to provide information on this emerging microorganism to effectively treat and control any epidemiological event caused by Aeromonas spp. in the future. [ABSTRACT FROM AUTHOR]

A novel predatory bacterium, strain LBG001 T , has been isolated from Reynosa, Mexico. The 16S rRNA shares approximately 97 % sequence identity with many reported strains in the genus Bdellovibrio including the type strain Bdellovibrio bacteriovorus HD100 T . Phylogenetic trees based on the 16S rRNA gene and on 30 concatenated housekeeping genes or core genes showed that LBG001 T is on a separate branch from the B. bacteriovorus group. LBG0001 T has a genome size of 3 582 323 bp with a G+C content of 43.1 mol %. The average nucleotide identity, average amino acid identity and digital DNA-DNA hybridization values with other members of the genus Bdellovibrio (<79, <72 and <17 %, respectively) qualifies the strain to represent a new species in the genus. Strain LBG001 T formed visible plaques on all 10 tested Gram-negative bacterial species. The phenotypic characteristics, phylogenetic analysis and genomic taxonomic studies support the classification of the strain as representing a new species for which the name Bdellovibrio reynosensis sp. nov. is proposed. The type strain is LBG001 T (=ATCC TSD-288 T = CM-CNRG 0932 T ).

Stenotrophomonas' metabolic versatility plays important roles in the remediation of contaminated environment and plant growth promotion. We investigated two Stenotrophomonas strains isolated from textile polluted sewage for their ability to decolorize and degrade azo dyes. Two Stenotrophomonas strains (TepeL and TepeS) were isolated from textile effluents (Tepetitla, Mexico) using the selective agar Stenotrophomonas vancomycin, imipenem, amphotericin B agar (SVIA). Isolates' identity was determined by the sequencing of their partial 16S rRNA fragments. Their abilities to decolorize dyes were tested in a Luria broth supplemented with varying concentrations (50 mg/L-1 g/L) of textile dyes (acidic red, methyl orange, reactive green, acidic yellow, and reactive black). Fourier-transform infrared (FTIR) spectroscopy and ultra-performance liquid chromatography-mass spectrometry (UPLC-MS) metabolite analyses were used to determine the effect of the isolates' growth on the dyes (acidic red, methyl orange). We also identified the enzymes that may be involved in the degradation process. Phylogenetic analysis based on the 16S rDNA sequences showed that the isolates belong to the genus Stenotrophomonas. Stenotrophomonas sp. TepeL and TepeS respectively decolorize all the azo dyes at the tested concentration except at 1 g/L and degraded the azo dyes. The degradation resulted in the formation of N, N-dimethyl p-phenylenediamine, and sodium 4-amino-1-naphthalenesulfonate from methyl orange and acid red. TepeL and TepeS rapidly decolorized and degraded the azo dyes tested. This result showed that the two isolates have a good potential for the decontamination of textile effluents., (© 2021. Sociedade Brasileira de Microbiologia.)

Background: Stenotrophomonas species are multi-resistant bacteria with ability to cause opportunistic infections., Objective: We isolated 45 Stenotrophomonas species from soil, sewage and the clinic with the aim of investigating their susceptibility to commonly used antimicrobial agents., Methodology: The identities of isolates were confirmed with 16S rRNA gene sequence and MALDI-TOF analysis. Anti-microbial resistance, biofilm production and clonal diversity were also evaluated. The minimum inhibitory concentration technique as described by Clinical & Laboratory Standards Institute: CLSI Guidelines (CLSI) was employed for the evaluation of isolate susceptibility to antibiotics., Result: Forty-five Stenotrophomonas species which include 36 environmental strains and 9 clinical strains of S. maltophilia were considered in this study. 32 (88.9 %) environmental strains were identified to be S. maltophilia , 2 (5.6 %) were Stenotrophomonas nitritireducens , and 2 (5.6 %) cluster as Stenotrophomonas spp. Stenotrophomonas isolates were resistant to at least six of the antibiotics tested, including Trimethoprim / Sulfamethoxazole ( SXT )., Conclusion: Environmental isolates from this study were resistant to SXT which is commonly used for the treatment of S. maltophilia infections. This informs the need for good public hygiene as the environment could be a reservoir of multi-resistant bacteria. It also buttresses the importance of surveillance study in the management of bacterial resistance., (© 2020 Elufisan TO et al.)

Objective: To establish a description of the psychiatric population of the Instituto Nacional de Perinatología (INPer), as well as of the exposed newborns to psychopharmacological treatment during the gestation., Material and Method: One hundred forty-six women were gathered, by means of serial files; 85 of them had an obstetric episode of high risk and 61 were assisted in the institution due to gynecological alterations. A clinical psychologist and a psychiatrist carried out, each one, an interview and the clinical history of all the women. Once the type diagnosis was determined (DSM-IV), they received psicotherapeutical, pharmacological or mixed treatment, until the resolution of the obstetric episode and the gathering of the neonatal data., Results: The findings reported that the prevalence or mental disorders (DSM-IV) that are not adaptive at the INPer is 1.8%. The diagnostic distribution of the psychiatric population ranked in first place the affective disorders (63.7%), particularly major depression disorder (42.5%). These percentages correspond at the institutional total population's 1.19 and 0.79. As for the treatment type, 57 women received psychotherapy, 75 received psychopharmacological treatment and 14 received both treatments. The newborn babies of obstetric patients who received psychopharmacological treatment did not show differences in Apgar, weight, size, complications or obstetric resolution in comparison with patients who received psychotherapy and again with respect to institutional media., Discussion: The prevalence found in the Institution is significantly inferior to that reported at a national and global level, due to the use of two diagnostic interviews by mental health specialists. The wrong use of the sieve is one of the reasons for overdiagnosis in mental health.

Onchocerciasis is a serious disease vectored by black flies in the genus Simulium that are infected with the filarial parasite Onchocerca volvulus. In the Americas, black flies of the Simulium ochraceum s.l. species complex are important vectors of this parasite. Cytological studies have suggested that this species complex consists of at least three cytotypes that inhabit distinct habitats. In this study, the NADH dehydrogenase subunit four (ND4) and internal transcribed spacer (ITS) of the ribosomal RNA gene cluster were used to explore the degree of genetic diversity among S. ochraceum s.l. populations found in the three O. volvulus foci in Mexico. Both sequence regions were found to exhibit intra- and interpopulation variation. Four different ND4 alleles were found among the populations examined. Similarly, variation was noted in the ITS domain sequences within and among populations. Variation within the ITS sequence was primarily confined to a complex microsatellite locus. Four ITS length variants were observed, two of which were only seen in flies collected from the onchocerciasis focus in northern Chiapas. These data suggest that the ND4 and ITS sequences may prove to be useful markers for exploring interactions within and among the S. ochraceum s.l. populations in Mexico.