Analysis for the presence of determinants involved in the transport of mercury across bacterial membrane from polluted water bodies of India

Abstract

Mercury, which is ubiquitous and recalcitrant to biodegradation processes, threatens human health by escaping to the environment via various natural and anthropogenic activities. Non-biodegradability of mercury pollutants has necessitated the development and implementation of economic alternatives with promising potential to remove metals from the environment. Enhancement of microbial based remediation strategies through genetic engineering approaches provides one such alternative with a promising future. In this study, bacterial isolates inhabiting polluted sites were screened for tolerance to varying concentrations of mercuric chloride. Following identification, several Pseudomonas and Klebsiella species were found to exhibit the highest tolerance to both organic and inorganic mercury. Screened bacterial isolates were examined for their genetic make-up in terms of the presence of genes (merP and merT) involved in the transport of mercury across the membrane either alone or in combination to deal with the toxic mercury. Gene sequence analysis revealed that the merP gene showed 86–99% homology, while the merT gene showed >98% homology with previously reported sequences. By exploring the genes involved in imparting metal resistance to bacteria, this study will serve to highlight the credentials that are particularly advantageous for their practical application to remediation of mercury from the environment.

Bioremediation treatment process through mercury-resistant bacteria isolated from Mithi river

“…and Klebsiella sp. were reported in study by Jan et al (2016) was capable of tolerating 148 ppm of mercury, while the Acinetobacter sp. and Klebsiella sp.…”

Determinantes Genéticos Y Sus Mecanismos De Acción Implicados en La Resistencia Bacteriana a Metales Pesados: Una Revisión.

“…Tras la unión de Hg 2+ , los cambios de conformación de MerR inducen un subenrollamiento del ADN promotor, facilitando la formación de un complejo abierto para iniciar la transcripción (32).Los genes merP y merT se distribuyen por todo el árbol filogenético(33). Por el contrario, Jan et al(34) identificaron que de 18 cepas aisladas de sitios contaminados de la India, 14 aislados portaban el gen merP y solo 12 cepas el gen merT. Principalmente, P. aeruginosa ARY1 y Klebsiella sp.…”