Cobalt(II) complexes derived from a 2-aminobenzimidazole-thiazoline ligand: Synthesis, characterization, crystal structures and antimicrobial activity studies

As part of our ongoing studies related with the coordination chemistry of 2-thiazoline derivatives with transition ions, we report the synthesis of a new class of structurally novel complexes containing in their structures a 2-aminobenzimidazole ring. The resulting compound, 2-(2-aminobenzimidazole-1-yl)-2-thiazoline (BzTn), and two cobalt(II) complexes have been structurally characterized by means of physical measurements. The crystal structures of BzTn, [CoCl2(BzTn)2] (1) and [CoBr2(BzTn)2] (2) have been determined by single crystal X-ray diffraction. In both Co(II) complexes, BzTn acts as a monodentate ligand through nitrogen atom of benzimidazole ring. The distorted tetrahedral environmental around the Co(II) ions is completed with two halide ions. Besides that, the newly synthesized compounds were screened for their antimicrobial activity against 6 strains of bacteria: S. aureus, E. coli, S. epidermidis. B. subtilis, E. faecalis y P. aeruginosa.This work was supported by Junta de Extremadura grants (GR18062 and GR18096) for financial support.peerReviewe

Structural studies on the regulation of arabidopsis thaliana ion homeostasis through the cbl-cipk pathway

Resumen del Poster presentado en Environment Workshop 2013: Genomic, Physiological and Breeding Approaches for Enhancing Drought Resistance in Crops. Baeza (Spain), 23-25 September (2013)The regulation of ionic transport in plants is essential because it establishes the key physicochemical parameters for cell function. Under abiotic stress, the intracellular levels of pH, potassium (K+) and toxic cations, such as Na+, change and this affect multiple cellular systems. Consequently, the knowledge of the molecular mechanism that regulates the ionic transport is fundamental and provides opportunities to use plants to our benefit [1]. The plant cells use calcium-signaling pathways to activate certain ion channels providing the correct response to a particular stress situation. As the most abundant cation in a living plant cell, K+ is an essential ion for processes of growth, development, maintenance of turgor pressure, and plasma membrane polarization [2]. Plants living under low K+ conditions often adapt their K+ uptake through the CBL-CIPK calcium-signaling pathway, that mobilizes K+ uptake in roots [3]. Under K+ deficiency, a CBL calcium sensor activates a CIPK kinase [3] that in turn phosphorilates and activate the K+ channel. When K+ levels are restored, a phosphatase dephosphorilates and inactivates the channel (Fig. 1) [5]. We have carried out structural studies with the kinase domain and its binding partner, the interacting region of the K+ channel, to understand at molecular level how K+ uptake is regulated under stress conditions. [1] M.J. Sánchez-Barrena, M. Martínez-Ripoll, A. Albert Int. J. Mol. Sci. 2013, 14, 5734 [2] R.E. Hirsch, B.D. Lewis, E.P. Spalding, M.R. Sussman Science. 1998, 280, 127. [3] L.Li, B.G. Kim, Y.H. Cheong, G.K. Pandey, S. Luan Proc. Natl. Acad. Sci. USA, 2006,103, 12625 [4] J. Xu, H.D. Li, L.Q. Chen Y. Wnag, L.L. Liu, L. He, W.H. Wu Cell, 2006, 125, 1347. [5] S.C. Lee, W.Z. Lan, B.G. Kim, L.Li, Y.H. Cheong, G.K. Pandey, B.B. Buchanan, S. Luan Proc. Natl. Acad. Sci. USA, 2007, 40, 15959.Peer reviewe

Structure of Ligand-Bound Intermediates of Crop ABA Receptors Highlights PP2C as Necessary ABA Co-receptor

This article has been accepted for publication in Molecular Plant Published by Oxford University Press.This work was funded by grants from MINECO (BFU2014-59796-R to A. A. and BIO2014-52537-R to P.L.R.). J.L.-J was supported by a Juan de la Cierva contract from MINECO and by the Marie Sklodowska-Curie Action H2020-MSCA-IF-2015-707477.Moreno-Alvero, M.; Yunta, C.; González Guzmán, M.; Lozano Juste, J.; Benavente, J.; Arbona, V.; Menendez, M.... (2017). Structure of Ligand-Bound Intermediates of Crop ABA Receptors Highlights PP2C as Necessary ABA Co-receptor. Molecular Plant. 10(9):1250-1253. https://doi.org/10.1016/j.molp.2017.07.004S1250125310

Tomato PYR/PYL/RCAR ABA receptors show high expression in root, differential sensitivity to the ABA-agonist quinabactin and capability to enhance plant drought resistance

This article contains supplementary data at: http://jxb.oxfordjournals.org/content/65/15/4451/suppl/DC1 © The Author 2014. Published by Oxford University Press on behalf of the Society for Experimental Biology[EN] Abscisic acid (ABA) plays a crucial role in the plant’s response to both biotic and abiotic stress. Sustainable production of food faces several key challenges, particularly the generation of new varieties with improved water use efciency and drought tolerance. Different studies have shown the potential applications of Arabidopsis PYR/PYL/ RCAR ABA receptors to enhance plant drought resistance. Consequently the functional characterization of orthologous genes in crops holds promise for agriculture. The full set of tomato (Solanum lycopersicum) PYR/PYL/RCAR ABA receptors have been identied here. From the 15 putative tomato ABA receptors, 14 of them could be grouped in three subfamilies that correlated well with corresponding Arabidopsis subfamilies. High levels of expression of PYR/ PYL/RCAR genes was found in tomato root, and some genes showed predominant expression in leaf and fruit tissues. Functional characterization of tomato receptors was performed through interaction assays with Arabidopsis and tomato clade A protein phosphatase type 2Cs (PP2Cs) as well as phosphatase inhibition studies. Tomato receptors were able to inhibit the activity of clade A PP2Cs differentially in an ABA-dependent manner, and at least three receptors were sensitive to the ABA agonist quinabactin, which inhibited tomato seed germination. Indeed, the chemical activation of ABA signalling induced by quinabactin was able to activate stress-responsive genes. Both dimeric and monomeric tomato receptors were functional in Arabidopsis plant cells, but only overexpression of monomeric-type receptors conferred enhanced drought resistance. In summary, gene expression analyses, and chemical and transgenic approaches revealed distinct properties of tomato PYR/PYL/RCAR ABA receptors that might have biotechnological implications.This work was supported by the Ministerio de Ciencia e Innovacion, Fondo Europeo de Desarrollo Regional and Consejo Superior de Investigaciones Cientificas (grants BIO2011-23446 to PLR, BFU2011-25384 to AA, and Fontagro and COST1106 for networking activities to AG); fellowships to LR and MP; and a Juan de la Cierva contract to MGG. Cristina Martinez-Andujar and the Bioinformatics Core Service of the IBMCP are acknowledged for the SlEF1a marker and help in bioinformatics analyses, respectively.González Guzmán, M.; Rodriguez, L.; Lorenzo Orts, L.; Pons Puig, C.; Sarrion-Perdigones, A.; Fernandez, MA.; Peirats Llobet, M.... (2014). Tomato PYR/PYL/RCAR ABA receptors show high expression in root, differential sensitivity to the ABA-agonist quinabactin and capability to enhance plant drought resistance. Journal of Experimental Botany. 65(15):4451-4464. https://doi.org/10.1093/jxb/eru219S44514464651