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Biology subjects

Barauna, R. A.

Publications and source records attributed to Barauna, R. A..

2 recordsLinked to original sources

Antimicrobial Susceptibility Profiles of Bacteria Isolated from The Ozama River in Santo Domingo, Dominican Republic

The dissemination of antimicrobial-resistant bacteria in environmental waters is an emerging concern in medical and industrial settings. In the present study, our research team analyzed superficial water samples from 3 different collection sites along the Ozama River, the most important river in the Dominican metropolitan area. Seventy-six isolates were obtained from culture media previously enriched with cefotaxime and imipenem and subsequently identified by MALDI-ToF. Our isolates spanned 12 genera of bacteria; over 30% were of clinical relevance, and 43% exhibited a phenotype classified as multi-drug resistance. The most frequent species identified as Stenotrophomonas maltophilia (n = 33), an emerging nosocomial pathogen. This study constitutes part of the initiative to understand the profiles of the perils of multi-drug resistance in metropolitan areas of the Dominican Republic: a nation with poor antibiotic use regulation. IMPORTANCENearly two billion people are sourcing their water from low-quality reservoirs world-wide. These reservoirs consist of contaminated waters with anthropogenic pollutants such as antibiotics, disinfectants, and other substances used to treat water in societies with scarce resources and unregulated industries. Furthermore, the exposure of these antibiotics to potable water reservoirs promotes the increase of clinically relevant bacteria with antibiotic-resistance capabilities, becoming a public health crisis. Therefore, treating patients with infectious diseases and providing prophylactic measures against infection-associated conditions (such as post-surgical recovery) has become progressively more difficult. Based on this evidence frame, it is of considerable importance to analyze the bacterial profiles of rivers that fall prey to anthropogenic contamination, as these investigations on antibiotic resistance will, of course, benefit the life of humans.

microbiology↗

Human activities impact microbial communities of Amazon Mangroves

Mangroves provide a unique ecological environment for complex microbial communities. They are particularly important in controlling the chemical environment of the ecosystem. Microbial diversity analyses of these ecosystems help us understand the environmental dynamics and the changes due to impacts. Amazonian mangroves are distributed across Amapa, Para and Maranhao states occupying an area of 9,000 km2 and correspond to 70% of the mangroves in Brazil, in which studies on microbial biodiversity are extremely rare. The present study aimed to determine changes in microbial community structure along the PA-458 highway that divided the mangrove. Mangrove samples were collected from three zones, (i) under anthropogenic actions, (ii) in the process of recovery and (ii) preserved. Total DNA was extracted, submitted for 16S rDNA amplification and sequenced on the Illumina MiSeq platform. Reads were analyzed using USEARCH tools and packages available in R Platform. The most abundant phyla were Proteobacteria, followed by Firmicutes and Bacteroidetes in all three mangrove locations. Genera such as Desulfuromonas, Desulfatiglans, Collinsella, Dorea, Dialister were not found in the impacted mangrove. The impacted mangrove proved to be ecologically different from other mangroves. Our results show that human impact in the mangrove areas has resulted in loss of biodiversity, caused by the construction of the PA-458 highway, reducing the support and maintenance of habitat life and the ecosystems resilience to disturbance.

genetics↗