Root uptake of lipophilic zinc-rhamnolipid complexes

This study investigated the formation and plant uptake of lipophilic metal-rhamnolipid complexes. Monorhamnosyl and dirhamnosyl rhamnolipids formed lipophilic complexes with copper (Cu), manganese (Mn), and zinc (Zn). Rhamnolipids significantly increased Zn absorption by Brassica napus var. Pinnacle roots in 65Zn-spiked ice-cold solutions, compared with ZnSO4 alone. Therefore, rhamnolipid appeared to facilitate Zn absorption via a nonmetabolically mediated pathway. Synchrotron XRF and XAS showed that Zn was present in roots as Zn-phytate-like compounds when roots were treated with Zn-free solutions, ZnSO4, or Zn-EDTA. With rhamnolipid application, Zn was predominantly found in roots as the Zn-rhamnolipid complex. When applied to a calcareous soil, rhamnolipids increased dry matter production and Zn concentrations in durum (Triticum durum L. cv. Balcali-2000) and bread wheat (Triticum aestivum L. cv. BDME-10) shoots. Rhamnolipids either increased total plant uptake of Zn from the soil or increased Zn translocation by reducing the prevalence of insoluble Zn-phytate-like compounds in roots

Supplemental macronutrients and microbial fermentation products improve the uptake and transport of foliar applied zinc in sunflower (Helianthus annuus L.) plants. Studies utilizing micro X-ray florescence.

Enhancing nutrient uptake and the subsequent elemental transport from the sites of application to sites of utilization is of great importance to the science and practical field application of foliar fertilizers. The aim of this study was to investigate the mobility of various foliar applied zinc (Zn) formulations in sunflower (Helianthus annuus L.) and to evaluate the effects of the addition of an organic biostimulant on phloem loading and elemental mobility. This was achieved by application of foliar formulations to the blade of sunflower (H. annuus L.) and high-resolution elemental imaging with micro X-ray fluorescence (μ-XRF) to visualize Zn within the vascular system of the leaf petiole. Although no significant increase of total Zn in petioles was determined by inductively-coupled plasma mass-spectrometer, μ-XRF elemental imaging showed a clear enrichment of Zn in the vascular tissues within the sunflower petioles treated with foliar fertilizers containing Zn. The concentration of Zn in the vascular of sunflower petioles was increased when Zn was applied with other microelements with EDTA (commercial product Kick-Off) as compared with an equimolar concentration of ZnSO4 alone. The addition of macronutrients N, P, K (commercial product CleanStart) to the Kick-Off Zn fertilizer, further increased vascular system Zn concentrations while the addition of the microbially derived organic biostimulant "GroZyme" resulted in a remarkable enhancement of Zn concentrations in the petiole vascular system. The study provides direct visualized evidence for phloem transport of foliar applied Zn out of sites of application in plants by using μ-XRF technique, and suggests that the formulation of the foliar applied Zn and the addition of the organic biostimulant GroZyme increases the mobility of Zn following its absorption by the leaf of sunflower

Кинетика химического осаждения сульфида цинка ZnS

The paper is devoted to kinetic methods of chemical bath deposition of zinc sulfide ZnS from aqueous alkaline solutions containing ehylenediamine complex zinc salt Zn(En)n 2+ and diamide of thiocarbonic acid N2H4CS. It is established that the rate of formation of ZnS is weakly dependent on pH, depends on the concentration of the precipitant ((N2H4CS) and decreases with increasing concentration of ligand (ethylenediamine). The calculation of the theoretical curves on the experimentally obtained kinetic equation shows a satisfactory description of experimental data that allows to recommend it to calculate the rate of formation of ZnS in aqueous alkaline solutions of N2H4CS.Работа посвящена исследованию кинетическими методами химического осаждения сульфида цинка ZnS из водных щелочных растворов, содержащих этилендиаминовую комплексную соль цинка Zn(En)n 2+ и диамид тиоугольной кислоты N2H4CS. Установлено, что скорость образования ZnS слабо зависит от величины рН, зависит от концентрации осадителя (N2H4CS) и уменьшается с увеличением концентрации лиганда (этилендиамина). Расчет теоретических кривых по полученному экспериментально кинетическому уравнению показывает удовлетворительное описание полученных экспериментальных данных, что позволяет рекомендовать его для расчета скорости образования ZnS в водных щелочных растворах N2H4CS.This work was done under financial support from RFBR (Project 16-03-00566).Работа выполнена при финансовой поддержке РФФИ (Проект № 16-03-00566)

SMC is recruited to oriC by ParB and promotes chromosome segregation in Streptococcus pneumoniae

Segregation of replicated chromosomes is an essential process in all organisms. How bacteria, such as the oval-shaped human pathogen Streptococcus pneumoniae, efficiently segregate their chromosomes is poorly understood. Here we show that the pneumococcal homologue of the DNA-binding protein ParB recruits S. pneumoniae condensin (SMC) to centromere-like DNA sequences (parS) that are located near the origin of replication, in a similar fashion as was shown for the rod-shaped model bacterium Bacillus subtilis. In contrast to B. subtilis, smc is not essential in S. pneumoniae, and Δsmc cells do not show an increased sensitivity to gyrase inhibitors or high temperatures. However, deletion of smc and/or parB results in a mild chromosome segregation defect. Our results show that S. pneumoniae contains a functional chromosome segregation machine that promotes efficient chromosome segregation by recruitment of SMC via ParB. Intriguingly, the data indicate that other, as of yet unknown mechanisms, are at play to ensure proper chromosome segregation in this organism.

The Addition of Zinc in Nutritive Rich Feed Containing Lemuru Oil to Growth and Birth Weight of Bali Cattle

An experiment was conducted to examine the addition of zinc in nutritive rich feed contained lemuru oil to growth and birth weight of Bali cattle. The experiment design used was randomized complete block design. The animal were randomly assigned into four group of treatments, i. e addition of 0, 75, 150 and 225 mg ZnSO4 kg-1 on nutritive rich feed (NRF) containing lemuru oil. The basal diet consist dried grass while NRF consisted of palm sugar, leucaena and glirisidia leaf meal, rice bran fermentation, fish meal, lemuru oil and urea. The crude protein content of NRF was 23%, while total digestible nutrient (TDN) was 70%. Addition ZnSO4 in the diet did not increase significantly zinc status, prostaglandin E2 (PGE2) concentration and ME retention. However, level of ZnSO4 addition increase significantly (P<0.01) zinc absorption, N retention, growth and birth weight of Bali Cattle (P<0.01). The fastest of growth was achieved at level of ZnSO4 addition of 150 mg ZnSO4.kg-1 NRF. (Animal Production 11(1): 59-65 (2009

Cyclic AMP pathway activation and extracellular zinc induce rapid intracellular zinc mobilization in Candida albicans

LK was supported by Innovation Fund Denmark, DK (4019-00019B). Pcovery ApS received funding from Wellcome Trust, Research Councils, UK (100480/Z/12), Novo Seeds, DK and Boehringer Ingelheim Venture Fund, D. DW is supported by a Sir Henry Dale Fellowship jointly funded by the Wellcome Trust and the Royal Society (102549/Z/13/Z), the Medical Research Council and University of Aberdeen (MR/N006364/1) and received support from a Wellcome Trust Strategic Award for Medical Mycology and Fungal Immunology (097377/Z/11/Z). The funders had no part in study design, data collection and interpretation, or the decision to submit the work for publication.Peer reviewedPublisher PD

Respon Padi Ir64 terhadap Pemberian Zn dengan Pengaturan Jadwal Tanam di Lahan Pasang Surut

In rice cultivation in tidal land are inundated land constraints. Under conditions of stagnant nutrient zinc is not available and the seedlings will experience stress submerged. This research aimed to evaluate the response of paddy ups and downs against the granting of multiple doses of zinc and setting planting schedule. The experiment was conducted in Teluk Sungkai, Kuala Cenaku in September 2014 - January 2015. The experiment was arranged in completely randomized factorial design with two factors and three replications. The first factor is the dose of zinc: 30 kg ZnSO4/ha, 40 kg ZnSO4/ha, and 50 kg ZnSO4/ha. The second factor is planting schedule: 5 days after the large tidal, 10 days after the large tidal, and 15 days after the large tidal. Based on this research the best dosage of zinc is 40 kg ZnSO4/ha and schedule 15 days after the large tidal better than the other planting schedule for paddy\u27s growth and production

The reaction mechanism of metallo-beta-lactamases is tuned by the conformation of an active site mobile loop

Carbapenems are "last resort" β-lactam antibiotics used to treat serious and life-threatening health care-associated infections caused by multidrug-resistant Gram-negative bacteria. Unfortunately, the worldwide spread of genes coding for carbapenemases among these bacteria is threatening these life-saving drugs. Metallo-β-lactamases (MβLs) are the largest family of carbapenemases. These are Zn(II)-dependent hydrolases that are active against almost all β-lactam antibiotics. Their catalytic mechanism and the features driving substrate specificity have been matter of intense debate. The active sites of MβLs are flanked by two loops, one of which, loop L3, was shown to adopt different conformations upon substrate or inhibitor binding, and thus are expected to play a role in substrate recognition. However, the sequence heterogeneity observed in this loop in different MβLs has limited the generalizations about its role. Here, we report the engineering of different loops within the scaffold of the clinically relevant carbapenemase NDM-1. We found that the loop sequence dictates its conformation in the unbound form of the enzyme, eliciting different degrees of active-site exposure. However, these structural changes have a minor impact on the substrate profile. Instead, we report that the loop conformation determines the protonation rate of key reaction intermediates accumulated during the hydrolysis of different β-lactams in all MβLs. This study demonstrates the existence of a direct link between the conformation of this loop and the mechanistic features of the enzyme, bringing to light an unexplored function of active-site loops on MβLs.Fil: Palacios, Antonela Rocio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Biología Molecular y Celular de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Biología Molecular y Celular de Rosario; ArgentinaFil: Mojica, María F.. Case Western Reserve University; Estados UnidosFil: Giannini, Estefanía. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Biología Molecular y Celular de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Biología Molecular y Celular de Rosario; ArgentinaFil: Taracila, Magdalena A.. Case Western Reserve University; Estados Unidos. Louis Stokes Veterans Affairs Medical Center; Estados UnidosFil: Bethel, Christopher R.. Louis Stokes Veterans Affairs Medical Center; Estados UnidosFil: Alzari, Pedro M.. Institut Pasteur de Paris; FranciaFil: Otero, Lisandro Horacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; ArgentinaFil: Klinke, Sebastian. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; ArgentinaFil: Llarrull, Leticia Irene. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Biología Molecular y Celular de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Biología Molecular y Celular de Rosario; ArgentinaFil: Bonomo, Robert A.. Case Western Reserve University; Estados UnidosFil: Vila, Alejandro Jose. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Biología Molecular y Celular de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Biología Molecular y Celular de Rosario; Argentin