Dna profiling and strategies for in planta localisation of bacteria intimately associated with Billbergia magnifica ssp. acutisepalia

Plant Cell, Tissue and Organ Culture (PCTOC) -     

Oncogenic translation directs spliceosome dynamics revealing an integral role for SF3A3 in breast cancer

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Induction of systemic resistance by mixtures of fungal and endophytic bacterial isolates against <Emphasis Type="Italic">Pythium aphanidermatum</Emphasis>

The efficacy of eight fungal and ten endophytic bacterial isolates were tested for their ability to inhibit the growth of Pythium aphanidermatum, the causal agent of chilli damping-off. In vitro studies revealed that Trichoderma viride (TVA) and endophytic Pseudomonas fluorescens (EBL 20-PF) showed the highest inhibition of mycelial growth (71.5%; 76.7%) of P. aphanidermatum. Both the antagonists were compatible with each other and they were tested alone and together in vivo for the control of P. aphanidermatum. Besides, the induction of defense-related enzymes such as peroxidase (PO), polyphenoloxidase (PPO), phenylalanine ammonia-lyase (PAL), PR-protein like β-1, 3-glucanase and the accumulation of phenolics in chilli seedlings due to the application of bioagents were also studied. Combined application of talc-based formulation of bio-agents and challenge inoculated with P. aphanidermatum recorded maximum induction of defense-related enzymes, PR-proteins and accumulation of phenolics compared with individual application. This study suggest that the increased induction of defense-related enzymes (four to fivefold) and phenolic content (sixfold) due to the combination treatment of bioagents might have involved in the reduction of damping-off incidence and in turn increased the plant growth and yield of chilli.     

Fouling and stability of polymers and composites in marine environment

Effect of biofouling on various polymers and composites such as, Polyurethane (PU), Silicone rubber (SR), Polyester (PET), Glass Fiber Reinforced Polymer (GFRP), Carbon fibre Reinforced Plastic (CFRP) and Syntactic foams (SF) deployed for a period of one year in marine waters at a depth of 1 m was studied. These materials find wide marine applications. SR with lowest surface energy was the least fouled. Maximum barnacle attachment was seen on hard surface (GFRP) and minimum on flexible surface (SR). Attachment of barnacles and polychaetes are positively correlated with surface energy. Fouling load is positively correlated with Surface energy and hardness. The surface energy, hardness and tensile strength reduced while surface roughness considerably increased during this period. Maximum gravimetric weight loss was seen in PET (7.49%) followed by PU (4.25%) and minimum in CFRP (0.45%). Maximum thermogravimetric weight loss was observed in PET (73.5% at 400 °C) followed by PU (71.1%) and least in SR (2.4%). Fourier Transform infrared spectrum revealed that carbonyl/oxidation indices decreased for PET, GFRP, CFRP, and SR indicating biotic degradation. The same index increased for PU indicating abiotic oxidation.     

Novel fluorescent protein from Hydnophora rigida possesses green emission

Fluorescent proteins are a family of proteins capable of producing fluorescence at various specific wavelengths of ultra violet light. We have previously reported the identification and characterization of a novel cyan fluorescent protein (HriCFP) from a reef coral species, Hydnophora rigida. In search of new members of the diverse family of fluorescent proteins, here we report a new green fluorescent protein (HriGFP) from H. rigida. HriGFP was identified, cloned, expressed in Escherichia coli and purified to homogeneity by metal affinity and size exclusion chromatography. The dynamic light scattering and gel filtration experiments suggested the presence of monomers in solution. The peptide mass fingerprint on the purified protein established the identity of HriGFP. HriGFP had excitation peak at 507 nm and emission peak at 527 nm. HriGFP was similar to HriCFP except the last 16 amino acid sequence at the C-terminal; however, they have shown least similarity with other known fluorescent proteins. Moreover the computational model suggests that HriGFP is a globular protein which consists of 6 α-helices and 3 β-sheets. Taken together our results suggested that HriGFP is a novel naturally occurring fluorescent protein that exists as a monomer in solution.     

Exosome mediated transfer of miRNA-140 promotes enhanced chondrogenic differentiation of bone marrow stem cells for enhanced cartilage repair and regeneration

Exosomes (EXs) are nanocarrier vesicles with 20-50 nm dimensions. They are involved in cell proliferation and differentiation and in protecting the integrity of materials. They can be isolated from plasma and immunoreactive components. Recent studies demonstrated their potential role in cartilage regeneration. To enhance their regenerative effect, molecules like microRNA (miR-140) can be loaded in EX that acts as RNA delivery systems. In this study, we combined EX with miR-140 to enhance cell differentiation by inducing membrane fusion and consequent miRNA released into the cytoplasm. The carrier RNA complex was successfully synthesized through freeze and thaw method leading to the formation of EX-containing miR-140. The EX morphology was assessed through transmission electron microscopy and their miR-140 uptake efficiency through real-time polymerase chain reaction (RT-PCR). The effects on bone marrow stem cells (BMSCs) were evaluated by in vitro cell culture. Cell adhesion and morphology were studied using a bio-scanning electron microscope and confocal laser scanning microscope. Differentiation BMSCs into chondrocytes was analyzed by RT-PCR and histology. Our results confirm the bioactive role of EX loaded with miR-140 in the differentiation of BMSCs into chondrocytes. EXs were biocompatible involving in the cartilage healing process through chromogenic differentiation of BMCS exploiting the tissue engineering route.     

The effects of oxygen–ozone therapy on regulatory T-cell responses in multiple sclerosis patients

Multiple sclerosis (MS) is a common degenerative disorder of the central nervous system. The decreased frequency and dysfunction of Treg cells cause inflammation and disease progression. Ozone autohemotherapy can be used as a potential therapeutic approach to regulate the immune system responses and inflammation in MS. For this purpose, 20 relapsing-remitting multiple sclerosis patients were under treatment with ozone twice weekly for 6 months. The frequency of Treg cell, the expression levels of the Treg cell-related factors (FoxP3, IL-10, TGF-β, miR-17, miR-27, and miR-146A), and the secretion levels of IL-10 and TGF-β were assessed. We found a significant increase in the number of Treg cells, expression levels of FoxP3, miRNAs (miR-17 and miR-27), IL-10, and TGF-β factors in patients after oxygen–ozone (O₂-O₃) therapy compared to before treatment. In contrast, oxygen–ozone therapy notably decreased the expression level of miR-146a in treated patients. Interestingly, the secretion levels of both IL-10 and TGF-β cytokines were considerably increased in both serum and supernatant of cultured peripheral blood mononuclear cells in posttreatment condition compared to pretreatment condition. According to results, oxygen–ozone therapy raised the frequency of Treg cell and its relevant factors in treated MS patients. Oxygen–ozone therapy would contribute to improving the MS patients by elevating the Treg cell responses.     

Characterization of IAA Production by the Mangrove Cyanobacterium Phormidium sp. MI405019 and Its Influence on Tobacco Seed Germination and Organogenesis

The production of indole-3-acetic acid (IAA) by a mangrove root-associated cyanobacterium, Phormidium sp. MI405019, was demonstrated in this study. The extracellular extract (ECE) of this cyanobacterial culture filtrate was tested on tobacco seed germination and callus differentiation. In ECE treatment, seed germination was increased by 40 % when compared to that of control. In addition, ECE also induced multiple roots from tobacco callus. Further, the factors such as concentration of l-tryptophan and NaCl (salinity) on IAA production were studied. IAA in the medium was initially increased up to a certain period and subsequently decreased in all salinity ranges tested. The amount of IAA production was decreased after 48 h in the culture grown in media amended with 2 % NaCl and without NaCl. However, the IAA concentration was increased up to 96 h in media containing 4 % NaCl. IAA produced by Phormidium sp. MI405019 was extracted from the culture filtrate and its identity was confirmed by thin-layer chromatography and ultra-fast liquid chromatography. To the best of our knowledge, this is the first report of IAA production by cyanobacteria isolated from a mangrove ecosystem. Based on the results in this study, the utilization of Phormidium sp. MI405019 in the aspects of mangrove growth promotion was discussed.     

Anticancer effects and lysosomal acidification in A549 cells by Astaxanthin from Haematococcus lacustris

Astaxanthin (AXN) is known to have health benefits by epidemiological studies. Therefore, it is of interest to assess the effect of AXN (derived from indigenous unicellular green alga Haematococcus lacustris) to modulate cell cycle arrest, lysosomal acidification and eventually apoptosis using in vitro in A549 lung cancer cells. Natural extracts of astaxanthin were obtained by standardized methods as reported earlier and characterized by standard HPLC and MS. Treatment of A549 cells with AXN (purified fraction) showed significant reduction in cell viability (about 50%) as compared to crude extract at 50µM concentration. Thus, we show the anticancer effects and lysosomal acidification in A549 cells by Astaxanthin from Haematococcus lacustris for further consideration. Together, our results demonstrated the anticancer potential of AXN from Haematococcus lacustris, which is found to be mediated via its ability to induce cell cycle arrest, lysosomal acidification and apoptotic induction.