Diversity of diazotrophs in arid and semi-arid regions of Haryana and evaluation of their plant growth promoting potential on Bt-cotton and pearl millet

This study revealed cultivable diazotrophs in arid and semi-arid regions of Haryana, India, harboring multiple plant growth promoting (PGP) traits, i.e. nitrogenase activity (18.84–337.26 nmol ethylene mg^?1 protein h^?1), indole-3-acetic acid production (42.4–1162.7 μg mL^?1), ammonia excretion (0.013–2.561 μg mL^?1), phosphate solubilization (55.8 %), and siderophore production (20.58 %). High diversity among diazotrophic bacterial isolates was deciphered by using amplified ribosomal DNA restriction analysis with MspI and HaeIII. All the isolates positively influenced the growth and yield of Bt-cotton and pearl millet plants under pot house conditions. On the basis of their plant growth promoting potential, 10 efficient bacterial strains were selected. Sequence analysis of these strains revealed two phyla of bacteria in the 16S rRNA library, which consisted of α and γ subclasses of the Proteobacteria and Firmicutes. The dominant group was Firmicutes (80 % of the total isolates), and the most dominant genus was Bacillus. Overall, our study reported bacterial strains with biofertilizer potential and could be considered as an excellent addition to existing beneficial microbes’ consortium for growth promotion of Bt-cotton and pearl millet plants in arid and semi-arid regions.     

Genotypic diversity in native rhizobial population nodulating Vicia faba in arid and semi-arid regions of Haryana state (India)

A Rhizobium–legume interaction stands out from other plant–microbe interactions as one in which a true developmental mutualism occurs. To study the genotypic diversity in native population of rhizobia-nodulating Vicia faba plants, we retrieved 64 rhizobial isolates from root nodules of faba bean grown in pots holding soils collected from arid and semi-arid regions of the state of Haryana, India. The amplification of nodC in all the isolates authenticated these as rhizobia. The nitrogen-fixing potential of the isolates was tested by the amplification of the nifH gene. Only 50 isolates out of 64 showed nifH gene amplification. The characterization of the isolates by amplified 16S rDNA restriction analysis (ARDRA) categorized these into 36 16S rDNA genotypes using a combination of MspI and HaeIII restriction enzymes. Majority of the isolates resolved into separate genotypes, indicating a wide diversity among them, which seemed to arise from their geographical origin and soil characteristics. These findings may be immensely useful in agriculture towards developing rhizobial inoculants specific for faba beans under arid and semi-arid conditions.     

The identification a novel,selective, non-steroidal,functional glucocorticoid receptor antagonist

The identification of novel, potent, non-steroidal/small molecule functional GR antagonist GSK1564023A selective over PR is described. Associated structure–activity relationships and the process of optimisation of an initial HTS hit are also described.     

The Leukocyte Nuclear Envelope Proteome Varies with Cell Activation and Contains Novel Transmembrane Proteins That Affect Genome Architecture

A favored hypothesis to explain the pathology underlying nuclear envelopathies is that mutations in nuclear envelope proteins alter genome/chromatin organization and thus gene expression. To identify nuclear envelope proteins that play roles in genome organization, we analyzed nuclear envelopes from resting and phytohemagglutinin-activated leukocytes because leukocytes have a particularly high density of peripheral chromatin that undergoes significant reorganization upon such activation. Thus, nuclear envelopes were isolated from leukocytes in the two states and analyzed by multidimensional protein identification technology using an approach that used expected contaminating membranes as subtractive fractions. A total of 3351 proteins were identified between both nuclear envelope data sets among which were 87 putative nuclear envelope transmembrane proteins (NETs) that were not identified in a previous proteomics analysis of liver nuclear envelopes. Nuclear envelope localization was confirmed for 11 new NETs using tagged fusion proteins and antibodies on spleen cryosections. 27% of the new proteins identified were unique to one or the other of the two leukocyte states. Differences in expression between activated and resting leukocytes were confirmed for some NETs by RT-PCR, and most of these proteins appear to only be expressed in certain types of blood cells. Several known proteins identified in both data sets have functions in chromatin organization and gene regulation. To test whether the novel NETs identified might include those that also regulate chromatin, nine were run through two screens for different chromatin effects. One screen found two NETs that can recruit a specific gene locus to the nuclear periphery, and the second found a different NET that promotes chromatin condensation. The variation in the protein milieu with pharmacological activation of the same cell population and consequences for gene regulation suggest that the nuclear envelope is a complex regulatory system with significant influences on genome organization.The nuclear envelope (NE)1 is a double membrane system consisting of the intermediate filament nuclear lamin polymer and associated proteins attached to the inner nuclear membrane (INM) (1), nuclear pore complexes (NPCs) that direct transport of soluble macromolecules in and out of the nucleus (2), and the outer nuclear membrane (ONM) and associated proteins. Structurally, the ONM is continuous with the endoplasmic reticulum (ER) and is studded with ribosomes (3), yet it also contains unique proteins, many of which connect the cytoskeleton to the NE (4). On the other side, lamins and many INM proteins directly connect chromatin to the NE. Lamins and an increasing number of nuclear envelope transmembrane proteins (NETs) have been linked to a similarly increasing number of diseases ranging from muscular dystrophy to neuropathy, dermopathy, lipodystrophy, bone disorders, and progeroid aging syndromes (5, 6).A favored hypothesis to explain how different NE proteins can produce such a wide range of disease pathologies is that chromatin-NE connections are disrupted with NE protein mutations, yielding changes in gene regulation. This hypothesis is supported by observations that the distribution of dense peripheral chromatin is affected in fibroblasts from patients with NE-linked muscular dystrophy, cardiomyopathy, mandibuloacral dysplasia, and progeria (7–10). Furthermore, many binding partners have been identified for NETs that are either chromatin proteins, enzymes that modify chromatin proteins, or regulators of gene expression (1, 11). These include markers of silent chromatin such as heterochromatin protein 1 (12) and proteins that modify chromatin to a silent conformation such as histone deacetylase 3 (13). The importance of the NE to global genome organization has been underscored by several recent studies that showed that affinity-based recruitment of a specific chromosome locus by the NE both pulled entire chromosomes to the periphery and affected gene regulation in complex ways (14–16).To identify NE proteins likely to be involved in genome organization, we turned to lymphocytes as a model system. Lymphocytes in the resting state tend to have massive amounts of dense peripheral chromatin as determined by electron microscopy studies. Upon activation with phytohemagglutinin, this dense chromatin largely dissipates as the cells actively express genes (17–20). Thus, to identify proteins that might be involved in tethering heterochromatin to the NE or in changing its organization, we analyzed the NE proteomes of leukocyte populations (∼70% lymphocytes) in both the resting and phytohemagglutinin (PHA)-activated states. The previously validated subtractive approach was applied (21) using microsomes and mitochondria, the principal membrane contaminants expected, as subtractive fractions.Many new NE proteins were identified that had not been identified in previous NE proteomics investigations using liver and neuroblastoma cells (21, 22). NE residence was confirmed for 12 novel NETs by expression of epitope-tagged versions and using antibodies on tissue cryosections.Roughly one-quarter of the proteins identified varied between the resting and activated states. Some NET differences between the two data sets were confirmed by RT-PCR. Among the known proteins identified were several that suggest that changes in NE composition associated with PHA activation contribute to gene regulation. Novel NETs identified also appear to play significant roles in genome organization/regulation as we found that several can either recruit a specific locus to the nuclear periphery or promote chromatin condensation. As several studies have implicated misregulation of chromatin organization in NE diseases (7, 8), these newly identified NETs may contribute to the diverse pathologies associated with NE diseases.     

Normal mode analysis of gamma form of oleic acid

Oleic acid is one of the major components of a variety of oils and its spectra are very complex due to the presence of a large number of conformational states (alpha, beta, gamma). In the present communication, an attempt has been made to unravel the complex spectra by calculating the normal modes and examining the spectral features such as line position, line width, band intensity, group frequency concept and spectral relationship between the finite and infinite systems.     

The sterol-binding antibiotic nystatin inhibits entry of non-opsonized Leishmania donovani into macrophages

Leishmania donovani is an obligate intracellular parasite that infects macrophages of the vertebrate host resulting in visceral leishmaniasis in humans, a major public health problem worldwide. The molecular mechanisms involved in internalization of Leishmania are still poorly characterized. We report here that cholesterol sequestration by the sterol-binding antifungal polyene antibiotic nystatin markedly inhibits binding and entry of non-opsonized L. donovani promastigotes into macrophages. Interestingly, these effects are not observed when serum-opsonized L. donovani are used for infectivity studies thus pointing the essential role of cholesterol in mediating entry of the parasite via the non-opsonic pathway. Based on our earlier results where leishmanial infectivity was shown to be sensitive to physical depletion of cholesterol from macrophages, these results indicate that the mere sequestration of cholesterol in the host plasma membrane is sufficient to inhibit the binding and entry of non-opsonized L. donovani. These results represent the first report on the effect of a cholesterol-sequestering agent on the entry of Leishmania parasites to host macrophages. More importantly, these findings offer the possibility of reevaluating the mechanism behind the effectiveness of current therapeutic strategies to treat leishmaniasis.