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Intertwining of Cellular Osmotic Stress Handling Mechanisms and Heavy Metal Accumulation

Authors:
Rosina Sánchez Thomas at National Autonomous University of Mexico
Rosina Sánchez Thomas
Mariel Hernández-Garnica at National Autonomous University of Mexico
Mariel Hernández-Garnica
Juan Carlos Granados Rivas at National Autonomous University of Mexico
Juan Carlos Granados Rivas
Emma Saavedra at National Institute of Cardiology
Emma Saavedra
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Abstract and Figures

Osmoregulation mechanisms are engaged in the detoxification and accumulation of heavy metals in plants, microalgae and other microorganisms. The present review paper analyzes osmotic resistance organisms and their heavy metal accumulation mechanisms closely related to osmoregulation. In prokaryotic and eukaryotic microorganisms, such as the green algae-like protist Euglena, osmotic and heavy metal stresses share similar cell responses and mechanisms. Likewise, some plants have developed specific mechanisms associated to water stress induced by salinity, flooding, or drought, which are also activated under heavy metal stress. Thus, synthesis of osmo-metabolites and strategies to maintain stable the intracellular water content under heavy metal exposure induce a state of apparent drought by blocking the water maintenance systems. Heavy metals affect the cellular redox state, triggering signaling pathways for intracellular water maintenance, which are mediated by the concentration of reactive oxygen species. Hence, cellular responses and mechanisms associated with osmotic stress, once fully elucidated, represent new opportunities to improve mechanistic strategies for bioremediation of heavy metal-polluted sites.
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Vol.:(0123456789)
Molecular Biotechnology
https://doi.org/10.1007/s12033-024-01351-y
REVIEW PAPER
Intertwining ofCellular Osmotic Stress Handling Mechanisms
andHeavy Metal Accumulation
RosinaSánchez‑Thomas1 · MarielHernández‑Garnica1· JuanCarlosGranados‑Rivas2· EmmaSaavedra1 ·
IgnacioPeñalosa‑Castro2 · SaraRodríguez‑Enríquez3 · RafaelMoreno‑Sánchez2
Received: 5 November 2024 / Accepted: 4 December 2024
© The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2024
Abstract
Osmoregulation mechanisms are engaged in the detoxification and accumulation of heavy metals in plants, microalgae and
other microorganisms. The present review paper analyzes osmotic resistance organisms and their heavy metal accumulation
mechanisms closely related to osmoregulation. In prokaryotic and eukaryotic microorganisms, such as the green algae-like
protist Euglena, osmotic and heavy metal stresses share similar cell responses and mechanisms. Likewise, some plants have
developed specific mechanisms associated to water stress induced by salinity, flooding, or drought, which are also activated
under heavy metal stress. Thus, synthesis of osmo-metabolites and strategies to maintain stable the intracellular water content
under heavy metal exposure induce a state of apparent drought by blocking the water maintenance systems. Heavy metals
affect the cellular redox state, triggering signaling pathways for intracellular water maintenance, which are mediated by the
concentration of reactive oxygen species. Hence, cellular responses and mechanisms associated with osmotic stress, once fully
elucidated, represent new opportunities to improve mechanistic strategies for bioremediation of heavy metal-polluted sites.
Keywords Heavy metal accumulation· Heavy metal bioremediation· Microorganisms· Osmotic stress· Osmoregulation
mechanisms
Abbreviations
AsPx Ascorbate peroxidase
AQP Aquaporin
Cys Cysteine
CWI Components of the cell wall integrity
pathway
DREB Dehydration responsive element binding
γ-EC Gamma-glutamyl cysteine
γ-ECS Gamma-glutamyl cysteine synthetase
GSH Glutathione
GS Glutathione synthase
HOG High osmolarity glycerol pathway
LEA Late embryogenesis abundant
Metal-(GSH)2 Bis-glutathionate of metal
MAPK Mitogen-activated protein kinases
PCs Phytochelatins
PCS Phytochelatin synthase
PPi Pyrophosphate
ROS Reactive oxygen species
SOD Superoxide dismutase
Introduction
Heavy metals and metalloids pollution is a current world-
wide environmental concern. Natural and anthropogenic
activity has caused enhancement of these elements in soil,
* Sara Rodríguez-Enríquez
sara.rodriguez@iztacala.unam.mx;
saren960104@hotmail.com
* Rafael Moreno-Sánchez
rafael.moreno@iztacala.unam.mx;
morenosanchez@hotmail.com
1 Departamento de Bioquímica, Instituto Nacional de
Cardiología, 14080MexicoCity, Mexico
2 Carrera de Biología, Laboratorio de Control Metabólico,
Facultad de Estudios Superiores Iztacala, Universidad
Nacional Autónoma de México, Los Reyes Ixtacala, Hab Los
Reyes Ixtacala Barrio de los Árboles/Barrio de los Héroes,
54090Tlalnepantla, Mexico
3 Carrera de Medico Cirujano, Laboratorio de Control
Metabólico, Facultad de Estudios Superiores Iztacala,
Universidad Nacional Autónoma de México, Los
Reyes Ixtacala, Hab Los Reyes Ixtacala Barrio de los
Árboles/Barrio de los Héroes, 54090Tlalnepantla, Mexico
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
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