Bacterioma de plastisfera y determinación de genes de resistencia antimicrobiana en vertedero de la región del Bíobío.
Loading...
Date
2024
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Universidad de Concepción
Abstract
Plastisfera se refiere a la comunidad microbiana de la superficie de las partículas de plástico. Aunque han sido bien estudiadas en ecosistemas acuáticos, los estudios terrestres han sido limitados. Este estudio se llevó a cabo en un vertedero de 40 años de antigüedad en Rocuant-Andalién, ubicado a 20 m del Océano Pacífico. Se muestrearon transectos de 1 km de longitud, totalizando seis sitios. El tipo de polímero de los residuos plásticos se identificó mediante espectroscopia infrarroja con transformada de Fourier (FT-IR), mientras que microscopia electrónica de barrido (SEM) se utilizó para obtener imágenes de la superficie del plástico. Se secuenció la región V3-V4 del gen 16S rRNA bacteriano para analizar la comunidad microbiana utilizando un enfoque metagenómico. Además, se analizó el gen intI1 mediante PCR convencional, revelando la presencia potencial de genes de resistencia a antibióticos de relevancia clínica humana en el 67 % de las seis parcelas. El tipo de plástico más abundante fue el polietileno de alta densidad (HDPE) (56 %). No se encontró relación entre el tipo de plástico y la presencia del gen intI1. La microscopía reveló la presencia de microorganismos en las muestras, incluidos bacilos, cocos y bacterias filamentosas, que formaban pequeños grupos en las superficies de plástico. La secuenciación de amplicones del 16S rRNA mostró un predominio de miembros pertenecientes a los filos Actinobacteria, Firmicutes y Proteobacteria en la mayoría de las muestras. Los índices de diversidad alfa indicaron una elevada diversidad y riqueza entre las muestras, pero no hubo diferencias estadísticas significativas entre los sitios. El análisis de diversidad beta indicó diferencias significativas en las comunidades bacterianas entre los lugares de muestreo, pero no entre los tipos de polímeros. Este estudio entrega información sobre las comunidades bacterianas asociadas a los residuos plásticos de los vertederos, incluida la alta diversidad, la documentación de diversos microorganismos y las diferencias en las comunidades bacterianas y los posibles problemas ecológicos y sanitarios relacionados con la resistencia a los antibióticos.
Plastispheres refer to microbial communities on the surface of plastic particles. Although they have been well studied in aquatic ecosystems, terrestrial studies are limited. This study was conducted at a 40-year-old landfill site in Rocuant-Andalién, close to 20 m from the Pacific Ocean. One 1 km-long transects were sampled, totaling six plots. The plastic debris polymer type was identified using Fourier-transform infrared spectroscopy (FT-IR) whereas scanning electron microscopy (SEM) was used to obtain images of the plastic. The V3-V4 region of the bacterial 16S rRNA gene was sequenced to analyze the microbial community using a metagenomic approach. Additionally, the intI1 gene was screened by conventional PCR, revealing the potencial presence of antibiotic-resistance genes of human clinical relevance in 67 % of the six plots. The most abundant plastic type was high density polyethylene (HDPE) (56 %). No association was found between the type of plastic and the presence of the intI1 gene. Microscopy revealed the presence of microorganisms in the samples, including bacilli, cocci, and filamentous bacteria, forming small clusters on the plastic surfaces. 16S rRNA amplicon sequencing showed a predominance of members belonging to the Actinobacteria, Firmicutes, and Proteobacteria phyla in most samples. Alpha diversity indices indicated high diversity and richness among the samples, but there were no significant statistical difference between the sites. Beta diversity analysis indicated significant differences in bacterial communities between sampling sites but not among polymer types. This study provides insights into the bacterial communities associated with landfill plastic waste, including high diversity, documenting diverse microorganisms and differences in the bacterial communities and potential ecological and health concerns related to antibiotic resistance.
Plastispheres refer to microbial communities on the surface of plastic particles. Although they have been well studied in aquatic ecosystems, terrestrial studies are limited. This study was conducted at a 40-year-old landfill site in Rocuant-Andalién, close to 20 m from the Pacific Ocean. One 1 km-long transects were sampled, totaling six plots. The plastic debris polymer type was identified using Fourier-transform infrared spectroscopy (FT-IR) whereas scanning electron microscopy (SEM) was used to obtain images of the plastic. The V3-V4 region of the bacterial 16S rRNA gene was sequenced to analyze the microbial community using a metagenomic approach. Additionally, the intI1 gene was screened by conventional PCR, revealing the potencial presence of antibiotic-resistance genes of human clinical relevance in 67 % of the six plots. The most abundant plastic type was high density polyethylene (HDPE) (56 %). No association was found between the type of plastic and the presence of the intI1 gene. Microscopy revealed the presence of microorganisms in the samples, including bacilli, cocci, and filamentous bacteria, forming small clusters on the plastic surfaces. 16S rRNA amplicon sequencing showed a predominance of members belonging to the Actinobacteria, Firmicutes, and Proteobacteria phyla in most samples. Alpha diversity indices indicated high diversity and richness among the samples, but there were no significant statistical difference between the sites. Beta diversity analysis indicated significant differences in bacterial communities between sampling sites but not among polymer types. This study provides insights into the bacterial communities associated with landfill plastic waste, including high diversity, documenting diverse microorganisms and differences in the bacterial communities and potential ecological and health concerns related to antibiotic resistance.
Description
Tesis presentada para optar al grado de Magíster en Ciencias con mención en Microbiología
Keywords
Vertederos, Plásticos, Microorganismos