ABSTRACT
Background & objectives: Bacterial biofilms a multi-layered defence, comprise extracellular DNA (eDNA) and proteins, protect bacteria from harmful environment and nutrient limitation and utilize the mutual benefits within a community. Bacterial biofilms also defend bacteria from harsh environments such as antibiotic treatment. This leads to poor antibiotic penetration, slow growth, adaptive stress responses, and formation of persister cells. This study was done to determine the relation of antibiotic resistance deciphered by the biofilms in Lactobacillus plantarum, a lactic acid bacteria (LAB) with probiotic significance. Methods: The gentamicin-resistant L. plantarum isolates were allowed to form biofilms and subjected to DNase I and proteinase K treatment. The optical density (OD) values were recorded for the biofilm assay and the cell count for the number of viable cells was taken for the control and the test samples. Percentage reduction was calculated based on the difference between the initial and final OD for both the parameters. Results: The biofilm assay revealed that the native L. plantarum isolates which were phenotypically susceptible, possessed the ability to form biofilms. The OD values were significantly decreased in comparison to the biofilm-forming control culture when these were treated with DNase I and proteinase K. Interpretation & conclusions: The study revealed that the biofilms formed by L. plantarum comprised of eDNA and proteins which was evidenced by the reduction in OD values and percentage in comparison to the control upon DNase I and proteinase K treatment. This indicates that the eDNA and biofilm matrix proteins are vital constituents of biofilms and may carry significant risk when coupled with antibiotic resistance.
ABSTRACT
La alergia es una reacción de hipersensibilidad iniciada por mecanismos inmunológicos y mediada por anticuerpos o células; se desencadena en individuos previamente sensibilizados a un alérgeno. En la mayoría de los casos, el anticuerpo responsable de la reacción alérgica es la inmunoglobulina E (IgE). Según la naturaleza y el mecanismo de entrada del alérgeno se producirá la IgE específica; en las alergias se afectan determinados órganos y tejidos con producción de sintomatologías específicas. Uno de los mecanismos que los eosinófilos utilizan durante la fase de respuesta de las alergias son sus trampas extracelulares (EET), que han sido poco estudiadas en cuanto a su inducción, regulación y función. Hasta el momento se conoce la presencia de dichas trampas en procesos inflamatorios intestinales, enfermedades autoinmunes y múltiples procesos infecciosos, pero se han hecho pocas investigaciones sobre su implicación en las enfermedades alérgicas. Este es un artículo de revisión sobre la estructura de las EET, las moléculas involucradas en su formación y la posible función que desempeñan en la patogénesis de las alergias. Además, se revisan los principales aspectos de los procesos celulares y moleculares involucrados en la inmunopatogénesis de las alergias y los aspectos centrales de la estructura, composición y funcionamiento de los eosinófilos.
Allergy is a hypersensitivity reaction initiated by specific immunologic mechanisms. It can be mediated by antibodies or cells, developed in individuals previously sensitized by an allergen. In most cases, the antibody responsible for the allergic reaction is immunoglobulin E (IgE). Depending on the nature and mechanism of entry of the allergen, it will bring about the production of specific IgE affecting certain organs and tissues with specific symptoms. Eosinophil extracellular DNA traps or EETs are one of the mechanisms used by eosinophils been well studied in terms of their induction, regulation and function. EETs have been detected in inflammatory intestinal processes, autoimmune diseases and multiple infectious diseases, but few investigations have been made about their involvement in allergic diseases. This is a review about the structure of EETs, the molecules involved in their formation, and their possible role in the pathogenesis of allergies. Furthermore, the main aspects of cellular and molecular processes involved in the immunopathogenesis of allergies, and the central aspects of the structure, composition and functioning of eosinophils are reviewed.