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Nitrogen and phosphorus dual stress significantly inhibited the maize growth and decreased the accumulation of nitrogen and phosphorus in plants. The co-application of nitrogen and phosphorus most significantly increased the biomass compared to the dual deficiency stress, and to our surprise, the repair effect of nitrogen application alone was basically similar to the repair effect of simultaneous application of nitrogen and phosphorus reflected in biomass as well as nitrogen and phosphorus content. Transcriptomic analysis showed that DEGs related to phosphorus transporters in N versus NP group and N versus P group were all up-regulated. These all confirm that the nitrogen application alone mitigated damages caused by low nitrogen and phosphorus dual stress comparable to that of nitrogen and phosphorus co-application. These indicate that the presence of nitrogen is conducive to the accumulation and transportation of phosphorus.

Summary: β‐1,6‐glucan is an important component of the fungal cell wall. The β‐1,6‐glucan synthase gene KRE6 was thought to be essential in the fungal pathogen Candida albicans because it could not be deleted in previous efforts. Also, the role of its homolog SKN1 was unclear because its deletion caused no defects. Here, we report the construction and characterization of kre6Δ/Δ, skn1Δ/Δ and kre6Δ/Δ skn1Δ/Δ mutants in C. albicans. While deleting KRE6 or SKN1 had no obvious phenotypic consequence, deleting both caused slow growth, cell separation failure, cell wall abnormalities, diminished hyphal growth, poor biofilm formation and loss of virulence in mice. Furthermore, the GPI‐linked cell surface proteins Hwp1 and the invasin Als3 or Ssa1 were not detected in kre6Δ/Δ skn1Δ/Δ mutant. In GMM medium, RT‐qPCR and western blotting revealed a constitutive expression of KRE6 and growth conditions‐associated activation of SKN1. Like many hypha‐specific genes, SKN1 is repressed by Nrg1, but its activation does not involve the transcription factor Efg1. Dysregulation of SKN1 reduces C. albicans ability to damage epithelial and endothelial cells and attenuates its virulence. Given the vital role of β‐1,6‐glucan synthesis in C. albicans physiology and virulence, Kre6 and Skn1 are worthy targets for developing antifungal agents. It has long been thought that the β‐1,6‐glucan synthase gene KRE6 is essential and its homolog SKN1 is redundant in Candida albcians. We show that KRE6 is not essential and SKN1 is functional and can compensate for the function of KRE6. We, for the first time, reveal that in addition to the chitin and β‐1,3‐glucan synthesis machinery, β‐1,6‐glucan synthesis also possesses a compensatory strategy in C. albicans. [ABSTRACT FROM AUTHOR]

RNAIII is known as the key effector of staphylococcal accessory gene regulator (agr) quorum-sensing system, which plays a central role in the pathogenesis of Staphylococcus aureus. As a regulatory RNA, RNAIII regulates multiple targets, including exoproteins and cell-wall-associated proteins. Lipoteichoic acid synthase (LtaS) is involved in the synthesis of lipoteichoic acid (LTA) that is one of the major components of cell wall. The chemical compound targeting to LtaS decreases S. aureus growth via blocking LTA production. Until now, the regulatory mechanism of LtaS expression is still not clear. The level of ltaS mRNA in S. aureus is analyzed by semi-quantitative RT-PCR analysis and qRT-PCR. The protein level of LtaS is determined by Western blotting. The putative interaction sites between RNAIII and LtaS mRNA are predicted. And LtaS-5′UTR-lacZ and LtaS-5′UTR-mutant-lacZ reporter vectors are constructed according to the putative interaction sites. Our data show that the expression of ltaS is regulated by RNAIII in S. aureus. The level of LtaS is significantly higher in the RNAIII deficient strain compared to its parent strain. In the further investigation, 5′UTR of ltaS was predicted to be the putative interaction site of RNAIII. The results of detection of β-galactosidase activities suggest that RNAIII can inhibit the expression level of LtaS through acting on the 5′UTR region of LtaS mRNA. Our finding presents that LtaS is another target of RNAIII and RNAIII suppresses the expression of LtaS via acting as an antisense RNA in S. aureus. [ABSTRACT FROM AUTHOR]

Several fibrinogen binding proteins (Fibs) play important roles in the pathogenesis of Staphylococcus aureus ( S. aureus). Most Fibs can promote the aggregation of platelets during infection, but the extracellular fibrinogen-binding protein (Efb) is an exception. It is reported that Efb can specifically bind fibrinogen and inhibit the aggregation of platelet with its N terminal. However, the biological significance of platelet aggregation inhibition in the infection caused by S. aureus is unclear until now. Here, we demonstrated that the persistence and aggregation of platelets were important for killing S. aureus in whole blood. It was found that the N terminal of Efb (EfbN) and platelets inhibitors could increase the survival of S. aureus in whole blood. The study in  vivo also showed that EfbN and platelets inhibitors could reduce the killing of S. aureus and increase the lethality rate of S. aureus in the acute infection mouse model. [ABSTRACT FROM AUTHOR]

The mechanism of phosphate (Pi)-mediated salt tolerance in maize is poorly understood. In this study, the effects of Pi (H2PO4−) on the salt tolerance of two contrasting genotypes was investigated in a pot experiment. We discovered that the application of 3 mM Pi could alleviate salt injury caused by 200 mM NaCl. High amounts of compatible solutes and low amounts of reactive oxygen species (ROS) were also observed under Pi application. Consistent with the increased tolerance, the total number of roots and the growth of shoots increased to relieve salt stress. This phenomenon could be associated with the observed increased expression of nitrate transporters. Furthermore, the seedlings presented a negative relationship between sodium (Na+) and Pi (low Na+ content and high Pi content), which is related to the genes ZmNHX1, ZmPHT1;8, and ZmPHT1;9, indicating that the exclusion of Na+ was promoted by high Pi uptake. However, high Na+ and low potassium (K+) efflux were detected in the roots, and these were positively correlated with two K+ transporters. These observations indicate that Na+ exclusion was directly induced by high K+ retention rather than Pi absorption. We conclude that maize salt tolerance increased in response to Pi application by promoting Na+ exclusion. [ABSTRACT FROM AUTHOR]

Fusarium ear rot (FER) incited by Fusarium verticillioides is a major disease of maize that reduces grain quality globally. Host resistance is the most suitable strategy for managing the disease. We report the results of genome-wide association study (GWAS) to detect alleles associated with increased resistance to FER in a set of 818 tropical maize inbred lines evaluated in three environments. Association tests performed using 43,424 single-nucleotide polymorphic (SNPs) markers identified 45 SNPs and 15 haplotypes that were significantly associated with FER resistance. Each associated SNP locus had relatively small additive effects on disease resistance and accounted for 1-4% of trait variation. These SNPs and haplotypes were located within or adjacent to 38 candidate genes, 21 of which were candidate genes associated with plant tolerance to stresses, including disease resistance. Linkage mapping in four biparental populations to validate GWAS results identified 15 quantitative trait loci (QTL) associated with F. verticillioides resistance. Integration of GWAS and QTL to the maize physical map showed eight colocated loci on chromosomes 2, 3, 4, 5, 9, and 10. QTL on chromosomes 2 and 9 are new. These results reveal that FER resistance is a complex trait that is conditioned by multiple genes with minor effects. The value of selection on identified markers for improving FER resistance is limited; rather, selection to combine small effect resistance alleles combined with genomic selection for polygenic background for both the target and general adaptation traits might be fruitful for increasing FER resistance in maize., (Copyright © 2016 Chen et al.)

The title compound, {[Nd(2)(CH(2)CHCOO)(6)(H(2)O)(3)]·3H(2)O}(n), was synthesized by hydro-thermal methods. The structure contains one-dimensional coordination polymers in which two distinct Nd(III) atoms show different coordination modes. One is coordinated by four bidentate acrylate ligands, two of which bridge Nd(III) atoms, and by two O atoms from a further two bridging acrylate ligands. The other Nd(III) atom is coordinated by two bidentate acrylate ligands, two O atoms from bridging acrylate ligands, and three water mol-ecules. Extensive hydrogen bonding between the coordinated and uncoordin-ated water mol-ecules and the O atoms of the acrylate ligands link the coordination polymers into a three-dimensional network.

In the title compound, {[Cu(C(7)H(3)NO(4))(H(2)O)(3)]·H(2)O}(n), the Cu(II) ion is bonded to three water mol-ecules, one N,O-bidentate pyridine-2,3-dicarboxyl-ate dianion and one O-bonded symmetry-generated dianion, resulting in a distorted CuNO(5) octa-hedral geometry. The bridging ligand results in an infinite chain. A network of O-H⋯O hydrogen bonds helps to establish the crystal structure.