Leishmania major: Cell type dependent distribution of a 43 kDa antigen related to silent information regulatory-2 protein family

In previous studies we have characterized several Leishmania major polypeptides and showed that one member of this group (LmSIR2rp) shared significant homology to silent information regulator 2 (SIR2) of Saccharomyces cerevisiae, a protein playing a role in both telomeric and mating type loci repression in these organisms. In the present study, by using molecular and immunological approaches, we could identify LmSIR2rp homologues in different Leishmania species and developmental stages (eg logarithmic (LP) and stationary phase promastigotes (SP) and amastigotes). The reactive antigen was also detected in Trypanosoma cruzi extracts. Surprisingly, immunofluorescence assays revealed that LmSIR2rp is associated mainly with cytoplasmic granules of different sizes and numbers depending on the life stage of the parasite used. No reactivity was observed in the nucleus, in agreement with the Western blot showing an absence of immunoreactivity of anti-LmSIR2rp immune serum against parasite nuclear extracts. Furthermore, immunoprecipitation of [³⁵S]methionine-labeled promastigote antigens after pulse chase experiments, using anti-LmSIR2rp fusion protein antibodies, showed that the protein is among parasite excreted-secreted antigens (ESA). Moreover, immunoflurescence assays conducted with short time incubations of either purified LmSIR2rp or viable promastigotes with murine macrophages, revealed that LmSIR2rp could be bound to the macrophage surface. The unexpected cytoplasmic localization of LmSIR2rp and its presence in ESA may suggest a new mode of action for silent information regulatory factor homologues.     

16.1% Efficient Hysteresis‐Free Mesostructured Perovskite Solar Cells Based on Synergistically Improved ZnO Nanorod Arrays

Significant efficiency improvements are reported in mesoscopic perovskite solar cells based on the development of a low‐temperature solution‐processed ZnO nanorod (NR) array exhibiting higher NR aspect ratio, enhanced electron density, and substantially reduced work function than conventional ZnO NRs. These features synergistically result in hysteresis‐free, scan‐independent, and stabilized devices with an efficiency of 16.1%. Electron‐rich, nitrogen‐doped ZnO (N:ZnO) NR‐based electron transporting materials (ETMs) with enhanced electron mobility produced using ammonium acetate show consistently higher efficiencies by one to three power points than undoped ZnO NRs. Additionally, the preferential electrostatic interaction between the ­nonpolar facets of N:ZnO and the conjugated polyelectrolyte polyethylenimine (PEI) has been relied on to promote the hydrothermal growth of high aspect ratio NR arrays and substantially improve the infiltration of the perovskite light absorber into the ETM. Using the same interactions, a conformal PEI coating on the electron‐rich high aspect ratio N:ZnO NR arrays is ­successfully applied, resulting in a favorable work function shift and altogether leading to the significant boost in efficiency from <10% up to >16%. These results largely surpass the state‐of‐the‐art PCE of ZnO‐based perovskite solar cells and highlight the benefits of synergistically combining mesoscale control with doping and surface modification.     

Loss of Prolyl Carboxypeptidase in Two-Kidney,One-Clip Goldblatt Hypertensive Mice

It is well documented that angiotensin (Ang) II contributes to kidney disease progression. The protease prolyl carboxypeptidase (PRCP) is highly expressed in the kidney and may be renoprotective by degrading Ang II to Ang-(1-7). The aim of the study was to investigate whether renal PRCP protein expression and activity are altered in two-kidney, one-clip (2K1C) Goldblatt hypertensive mice. Left renal artery was constricted by using 0.12 mm silver clips. Blood pressure was measured using telemetry over the eleven weeks of study period and revealed an immediate increase in 2K1C animals during the first week of clip placement which was followed by a gradual decrease to baseline blood pressure. Similarly, urinary albumin excretion was significantly increased one week after 2K1C and returned to baseline levels during the following weeks. At 2 weeks and at the end of the study, renal pathologies were exacerbated in the 2K1C model as revealed by a significant increase in mesangial expansion and renal fibrosis. Renal PRCP expression and activity were significantly reduced in clipped kidneys. Immunofluorescence revealed the loss of renal tubular PRCP but not glomerular PRCP. In contrast, expression of prolyl endopeptidase, another enzyme capable of converting Ang II into Ang-(1-7), was not affected, while angiotensin converting enzyme was elevated in unclipped kidneys and renin was increased in clipped kidneys. Results suggest that PRCP is suppressed in 2K1C and that this downregulation may attenuate renoprotective effects via impaired Ang II degradation by PRCP.     

Contrasting Effects of Farmyard Manure (FYM) and Compost for Remediation of Metal Contaminated Soil

We investigated effect of farm yard manure (FYM) and compost applied to metal contaminated soil at rate of 1% (FYM-1, compost-1), 2% (FYM-2, compost-2), and 3% (FYM-3, compost-3). FYM significantly (P < 0.001) increased dry weights of shoots and roots while compost increased root dry weight compared to control. Amendments significantly increased nickel (Ni) in shoots and roots of maize except compost applied at 1%. FYM-3 and -1 caused maximum Ni in shoots (11.42 mg kg^?1) and roots (80.92 mg kg^?1), respectively while compost-2 caused maximum Ni (14.08 mg kg^?1) and (163.87 mg kg^?1) in shoots and roots, respectively. Plants grown in pots amended with FYM-2 and compost-1 contained minimum Cu (30.12 and 30.11 mg kg^?1) in shoots, respectively. FYM-2 and compost-2 caused minimum zinc (Zn) (59.08 and 66.0 mg kg^?1) in maize shoots, respectively. FYM-2 caused minimum Mn in maize shoots while compost increased Mn in shoots and roots compared to control. FYM and compost increased the ammonium bicarbonate diethylene triamine penta acetic acid (AB-DTPA) extractable Ni and Mn in the soil and decreased Cu and Zn. Lower remediation factors for all metals with compost indicated that compost was effective to stabilize the metals in soil compared to FYM.     

Phylogenetic and Evolutionary Analyses of the Frizzled Gene Family in Common Carp (Cyprinus carpio) Provide Insights into Gene Expansion from Whole-Genome Duplications

In humans, the frizzled (FZD) gene family encodes 10 homologous proteins that commonly localize to the plasma membrane. Besides being associated with three main signaling pathways for cell development, most FZDs have different physiological effects and are major determinants in the development process of vertebrates and. Here, we identified and annotated the FZD genes in the whole-genome of common carp (Cyprinus carpio), a teleost fish, and determined their phylogenetic relationships to FZDs in other vertebrates. Our analyses revealed extensive gene duplications in the common carp that have led to the 26 FZD genes that we detected in the common carp genome. All 26 FZD genes were assigned orthology to the 10 FZD genes of on-land vertebrates, with none of genes being specific to the fish lineage. We postulated that the expansion of the FZD gene family in common carp was the result of an additional whole genome duplication event and that the FZD gene family in other teleosts has been lost in their evolution history with the reason that the functions of genes are redundant and conservation. Through the expression profiling of FZD genes in common carp, we speculate that the ancestral gene was likely capable of performing all functions and was expressed broadly, while some descendant duplicate genes only performed partial functions and were specifically expressed at certain stages of development.     

In vitro propagation of Caralluma tuberculata and evaluation of antioxidant potential

Present study describes rapid in vitro propagation of Caralluma tuberculata, a traditional medicinal plant, and antioxidant potential of calli and plants extracts. The highest callus induction rate (93.3%) with maximum weight of calli 5.2 g was achieved from shoot tip explants on MS medium supplemented with 9.04 μM 2,4-D and 4.44 μM BA. The maximum shoot induction rate (71.1%) with mean number of shoots 3.66 ± 1.53 and 4.6 cm average shoot length was observed on 13.32 μM BA, 4.52 μM 2,4-D and 2.89 μM GA3 appended in MS medium. The developed shoots were best rooted in the presence of 5.07 μM IAA with 3.0 ± 0.15 roots per plantlet. The plants were successfully acclimatized under in vivo conditions. The plants and calli extracts exhibited good antioxidant activities, however, plant extract activities were more pronounced. The phenolic compounds in plant and calli extracts were 0.16% and 0.057%, respectively. While the flavonoids were 0.092% in plant and 0.039% in calli extract. Total Phenolics, flavonoids; DPPH radical scavenging activity and reducing power potential distributed among different fractions depending upon polarity of the solvent. The highest DPPH scavenging activity and reducing power was exhibited by water fractions; 4.95 mg/mL and 0.729 OD at 10 mg/mL, respectively. The micropropagation protocol can be successfully used for large-scale multiplication and conservation of germplasm of this threatened plant. Furthermore, antioxidant value describes importance of this valuable plant as food and medicine.     

The NorM MATE Transporter from N.?gonorrhoeae: Insights into Drug and Ion Binding from Atomistic Molecular Dynamics Simulations

The multidrug and toxic compound extrusion transporters extrude a wide variety of substrates out of both mammalian and bacterial cells via the electrochemical gradient of protons and cations across the membrane. The substrates transported by these proteins include toxic metabolites and antimicrobial drugs. These proteins contribute to multidrug resistance in both mammalian and bacterial cells and are therefore extremely important from a biomedical perspective. Although specific residues of the protein are known to be responsible for the extrusion of solutes, mechanistic details and indeed structures of all the conformational states remain elusive. Here, we report the first, to our knowledge, simulation study of the recently resolved x-ray structure of the multidrug and toxic compound extrusion transporter, NorM from Neisseria gonorrhoeae (NorM_NG). Multiple, atomistic simulations of the unbound and bound forms of NorM in a phospholipid lipid bilayer allow us to identify the nature of the drug-protein/ion-protein interactions, and secondly determine how these interactions contribute to the conformational rearrangements of the protein. In particular, we identify the molecular rearrangements that occur to enable the Na⁺ ion to enter the cation-binding cavity even in the presence of a bound drug molecule. These include side chain flipping of a key residue, GLU-261 from pointing toward the central cavity to pointing toward the cation binding side when bound to a Na⁺ ion. Our simulations also provide support for cation binding in the drug-bound and apo states of NorM_NG.     

Assessment of the genetic diversity among Glyptosternum maculatum, an endemic fish of Yarlung Zangbo River, Tibet, China using SSR markers

The genetic diversity of Glyptosternum maculatum populations from Nyang River, Lhasa River, and Shetongmon Reach of Yarlung Zangbo River was assessed using six microsatellite markers. Overall, the genetic diversity across the three populations was low. The Shetongmon population exhibited the highest level of genetic diversity in terms of number of alleles and effective alleles, heterozygosity, and polymorphic information content value, followed by the Nyang population and Lhasa population. The analysis of molecular variance demonstrated that almost the variation (86.64%) occurred within populations. The differentiation among populations was not significant, and population structure was weak. These results revealed that three natural populations of G. maculatum are not genetically differentiated and the large disparity of living altitude did not caused genetic differentiation between different populations. Our observations will help identify the genetic relationship among populations to understand the genetic diversity of G. maculatum.     

The role of volatile and non-volatile antibiotics produced by Pseudomonas chlororaphis strain PA23 in its root colonization and control of Sclerotinia sclerotiorum

Pseudomonas chlororaphis strain PA23 has demonstrated excellent biocontrol in the canola phyllosphere. This bacterium produces the non-volatile antibiotics phenazine and pyrrolnitrin as well as the volatile antibiotics nonanal, benzothiazole and 2-ethyl-1-hexanol. In vitro experiments were conducted to study the effects of different mutations on the production of these three organic volatile antibiotics by PA23. In planta experiments in the greenhouse investigated the role of the non-volatile antibiotics on root colonization and biocontrol ability of PA23 against Sclerotinia sclerotiorum on sunflower. Analysis of phenazine- and pyrrolnitrin-deficient Tn mutants of PA23 revealed no differences in production of the three volatile antibiotics. On all sampling dates, PA23 applied alone or in combination with the mutants showed significantly higher (P = 0.05) root bacterial number and Sclerotinia wilt suppression (P = 0.05). Decline of the bacterial population seemed to be inversely proportional to/or negatively correlated with the number of antibiotics produced by PA23 but the relative importance of phenazine or pyrrolnitrin on root colonization and/or wilt suppression was not clear. In several cases, the strains producing at least one antibiotic maintained relatively higher bacterial numbers than non-producing strains. However, by 6 weeks after sowing, there was a rapid and significant (P = 0.05) increase in the proportion of introduced bacteria capable of producing at least one antibiotic over the total bacterial population. Furthermore, combining certain mutants with PA23 reduced the root colonization and biocontrol ability of PA23. Strain PA23-314 (gacS mutant) showed competitive colonization in comparison to the other mutants for most sampling dates.