Original Research ARTICLE
Marine archaeon Methanosarcina acetivorans enhances polyphosphate metabolism under persistent cadmium stress
- 1Instituto Nacional de Cardiologia Ignacio Chavez, Mexico
- 2Departamento de Bioquímica, Instituto Nacional de Cardiología, Mexico
- 3Other, Mexico
- 4Other, Mexico
- 5Instituto Nacional de Medicina Genómica (INMEGEN), Mexico
- 6Biotechnology Institute, National Autonomous University of Mexico, Mexico
- 7Department of Biochemistry, Faculty of Medicine, National Autonomous University of Mexico, Mexico
- 8Department of Physiology, Faculty of Medicine, National Autonomous University of Mexico, Mexico
Phosphate metabolism was studied to determine whether polyphosphate (polyP) pools play a role in the enhanced resistance against Cd2+ and metal-removal capacity of Cd2+-preadapted (CdPA) Methanosarcina acetivorans. Polyphosphate kinase (PPK), exopolyphosphatase (PPX) and phosphate transporter transcript levels and their activities increased in CdPA cells compared to control (Cnt) cells. K+ inhibited recombinant Ma-PPK and activated Ma-PPX, whereas divalent cations activated both enzymes. Metal-binding polyP and thiol-containing molecule contents, Cd2+-removal, and biofilm synthesis were significantly higher in CdPA cells>Cnt cells plus a single addition of Cd2+>Cnt cells. Also, CdPA cells showed a higher number of cadmium, sulfur, and phosphorus enriched-acidocalcisomes than control cells. Biochemical and physiological phenotype exhibited by CdPA cells returned to that of Cnt cells when cultured without Cd2+. Furthermore, no differences in the sequenced genomes upstream and downstream of the genes involved in Cd2+ resistance were found between CdPA and Cnt cells, suggesting phenotype loss rather than genome mutations induced by chronic Cd2+-exposure. Instead, a metabolic adaptation induced by Cd2+ stress was apparent. The dynamic ability of M. acetivorans to change its metabolism, depending on the environmental conditions, may be advantageous to remove cadmium in nature and biodigesters.
Keywords: heavy metal-binding molecules, polyphosphate kinase,, Exopolyphosphatase, biofilm induction, methanogenesis, archaeal metabolism
Received: 27 May 2019;
Accepted: 09 Oct 2019.
Copyright: © 2019 Jasso-Chávez, Lira-Silva, González-Sánchez, Larios Serrato, Mendoza-Monzoy, Pérez-Villatoro, Morett, Vega-Segura, Torres-Márquez, Zepeda-Rodríguez and Moreno-Sánchez. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
* Correspondence: PhD. Ricardo Jasso-Chávez, Instituto Nacional de Cardiologia Ignacio Chavez, Tlalpan, Mexico, firstname.lastname@example.org