Restoration of the soil fertility under Cr(VI) and artificial drought condition by the utilization of plant growth-promoting Bacillus spp. SSAU2.

The study explores the potential of an indigenous halo-tolerant microbe identified as Bacillus spp. SSAU-2 in enhancing soil fertility and promoting plant growth for sustainable agricultural practices under the influence of multiple abiotic stresses such as Cr(VI), high salinity, and artificial drought condition. The study investigated various factors influencing IAA synthesis by SSAU-2, such as pH (5 to 11), salinity (10 to 50 g/L), tryptophan concentration (0.5 to 1%), carbon (mannitol mand lactose), and nitrogen sources (peptone and tryptone). The highest IAA concentration was observed at pH 10 (1.695 mg/ml) and pH 11 (0.782 mg/ml). IAA synthesis was optimized at a salinity level of 30 g/l, with lower and higher salinity levels resulting in decreased IAA concentrations. Notably, the presence of mannitol and lactose significantly augmented IAA synthesis, while glucose and sucrose had inhibitory effects. Furthermore, peptone and tryptone played a pivotal role in enhancing IAA synthesis, while ammonium chloride exerted an inhibitory influence. SSAU-2 showed a diverse array of capabilities, including the synthesis of gibberellins, extracellular polymeric substances, siderophores, and hydrogen cyanide along with nitrogen fixation and ammonia production. The microbe could efficiently tolerate 45% PEG-6000 concentration and effectively produce IAA in 15% PEG concentration. It could also tolerate high concentration of Cr(VI) and synthesize IAA even in 50 ppm Cr(VI). The findings of this study provide valuable insights into harnessing the potential of indigenous microorganisms to promote plant growth, enhance soil fertility, and establish sustainable agricultural practices essential for restoring the health of ecosystems.

Assessing the Impact of Hexavalent Chromium (Cr VI) at Varied Concentrations on Spirulina platensis for Growth, Metal Sorption, and Photosynthetic Responses.

Spirulina platensis, a photosynthetic cyanobacterium, has garnered attention for its potential role in environmental remediation due to its ability to absorb and metabolize toxic heavy metals. Understanding its response toward toxicity of one of the most common contaminants, Cr(VI) is crucial for assessing its efficacy in bioremediation efforts. This study aims to investigate the physiological and biochemical responses of Spirulina platensis to varying concentrations of Cr(VI) from 0.5 to 5 ppm, shedding light on its potential as a bioindicator for environmental contamination and its suitability for bioremediation purposes. The impact of Cr(VI) on cell density, biosorption, pigment levels, nutrient content, fluorescence response, and photosynthetic efficiency was examined. The study revealed a gradual reduction in cell density, biomass production, and biosorption efficiency with increasing Cr(VI) concentrations. Pigment levels, carbohydrate, protein, and lipid content showed significant decreases, indicating physiological stress. Fluorescence response and photosynthetic efficiency were also adversely affected, suggesting alterations in electron transfer dynamics. A threshold for chromium toxicity was observed at 0.5 ppm, beyond which significant physiological disturbances occurred. This investigation highlights the sensitivity of Spirulina platensis to Cr(VI) toxicity and its potential as a bioindicator for heavy metal contamination. Metal sorption was highest in 0.5 ppm Cr(VI) with 56.56% removal. Notably, at lower concentrations, Cr(VI) acted as an intermediate electron acceptor, enhancing the electron transport chain and potentially increasing biomass under controlled conditions. The findings underscore the importance of understanding the mechanisms underlying heavy metal stress in microalgae for effective environmental remediation strategies. The research highlights the dual role of chromium(VI) in influencing S. platensis, depending on the concentration, and underscores the importance of understanding metal ion interactions with photosynthetic organisms for potential applications in bioremediation.

Bio Prospecting of Endophytes and PGPRs in Artemisinin Production for the Socio-economic Advancement.

The growing demand for Artemisia annua plants in healthcare, food, and pharmaceutical industries has led to increased cultivation efforts to extract a vital compound, Artemisinin. The efficacy of Artemisinin as a potent drug against malaria disease is well established but its limited natural abundance. However, the common practice of using chemical fertilizers for maximum yield has adverse effects on plant growth, development, and the quality of phytochemicals. To address these issues, the review discusses the alternative approach of harnessing beneficial rhizosphere microbiota, particularly plant growth-promoting rhizobacteria (PGPR). Microbes hold substantial biotechnological potential for augmenting medicinal plant production, offering an environmentally friendly and cost-effective means to enhance medicinal plant production. This review article aims to identify a suitable endophytic population capable of enabling Artemisia sp. to thrive amidst abiotic stress while simultaneously enhancing Artemisinin production, thereby broadening its availability to a larger population. Furthermore, by subjecting endophytes to diverse combinations of harsh conditions, this review sheds light on the modulation of essential artemisinin biosynthesis pathway genes, both up regulated and down regulated. The collective findings suggest that through the in vitro engineering of endophytic communities and their in vivo application to Artemisia plants cultivated in tribal population fields, artemisinin production can be significantly augmented. The overall aim of this review to explore the potential of harnessing microbial communities, their functions, and services to enhance the cultivation of medicinal plants. It outlines a promising path toward bolstering artemisinin production, which holds immense promise in the fight against malaria.

Microalgal consortia differentially modulate progressive adsorption of hexavalent chromium.

A set of experiments was conducted to provide significant insights of micro-algal consortia regarding chromium adsorption. Four monocultures; Scenedesmus dimorphus, Chlorella sp., Oscillatoria sp., and Lyngbya sp., and their synthetic consortia were evaluated initially for chromium bio-adsorption at four different regimes of hexavalent chromium i.e. 0.5, 1.0, 3.0 and 5.0 ppm. Based on findings, only 1.0 and 5.0 ppm were considered for future experiments. Consequently, three different types of monoculture and consortia cells namely; live cells, heat-killed cells, and pre-treated cells were prepared to enhance their adsorption potential. Maximal adsorption of 112% was obtained at the dose of 1.0 ppm with 0.1% SDS pre-treated consortia cells over live consortia cells. In support, atomic absorption spectroscopy, laser induced breakdown spectroscopy, pulse amplitude modulated chlorophyll fluorescence, and scanning electron microscopy were performed to assess the structural and functional changes within consortia and their utilization in mitigation of elevated chromium levels.

Phytosynthesis of Silver Nanoparticles Using Oscimum sanctum Leaf Extract and Studies on Its Antidiabetic, Antioxidant, and Antibacterial Properties.

The green synthesis of plasmonic metal nanoparticles (NPs) has gained considerable attention among researchers as it is cost-effective, environmentally friendly, energy-saving, and nontoxic. We have synthesized silver NPs (Ag NPs) with Oscimum sanctum (holy Tulsi) medicinal plant leaf extract by green synthesis methods. Further, we investigate the antibacterial, antioxidant, and antidiabetic activities of the synthesized Ag NPs. Oscimum sanctum leaf extract has secondary metabolites such as phenolic and flavonoid compounds, which play a significant role in the synthesis of Ag NPs. Subsequently, these bioactive molecules get adsorbed on the large surfaces of the synthesized NPs. Spectroscopic techniques such as X-ray diffraction (XRD), UV-visible absorption, Fourier-transform infrared, and scanning electron microscopy have been used to study and characterize the phytosynthesized Ag NPs. The XRD pattern confirms the formation of crystalline Ag NPs with a high degree of intensity. UV-visible absorption spectra confirm the surface plasmon resonance peak in the range of 440-450 nm. A scanning electron microscopy picture reveals homogeneous growth of Ag NPs with particle sizes of 200-400 nm; however, crystallite size along different planes has been estimated in the range of 18-23 nm. We have found that these Ag NPs synthesized with Oscimum sanctum leaf extract show inhibitory activity against α-amylase and α-glucosidase enzymes in vitro. Our findings further reveal that these Ag NPs are more effective in inhibiting the growth of Salmonella typhi bacteria as compared to other bacterial strains.

Evaluation of potent cyanobacteria species for UV-protecting compound synthesis using bicarbonate-based culture system.

The present investigation evaluates the potential of three cyanobacteria species Anabaena cylindrica, Nostoc commune and Synechococcus BDUSM-13 for photo-protecting mycosporine-like amino acids (MAAs) synthesis using bicarbonate-based culture system. Current investigations witnessed noteworthy bicarbonate tolerance of all species (NaHCO3; 0.5, 1 and 2 g L- 1) in terms of their growth rate, chlorophyll content, biomass productivity and carbon fixation ability. Among all strains, Synechococcus BDUSM-13 showed maximum surge in specific growth rate (i.e. 0.72 day-1) at 1 g L-1, productivity (i.e. 0.92 ± 0.06 g day-1 L-1) and chlorophyll content (i.e. 0.09 g L-1) at 2 g day-1 L-1. Synechococcus cells were also has the 0.48 g dw-1 carbon content with highest CO2 fixation rate (i.e. 0.653 g.CO2 mL-1 day-1) at 2 g L-1. Though, they were not able to produce MAAs after long UV-B exposure (i.e. 24 and 48 h). A. cylindrica strain was the most competent species for the bicarbonate-based approach, produced UV-protecting iminomycosporine compound (i.e. shinorine, λ max at 334 ± 2 nm) along with carbon fixation (i.e. 0.49 g CO2 mL-1 day-1) at 2 g L-1 NaHCO3. This suggests the bicarbonate supplementation during cultivation is a promising strategy to increase cellular abundance, biomass productivity and carbon fixation in cyanobacteria. However, UV-B irradiation may cause species-specific differences in the MAAs synthesis to produce UV-protecting compounds.

Genetic polymorphisms of matrix metalloproteinases and their inhibitors in potentially malignant and malignant lesions of the head and neck.

Matrix metalloproteinases (MMPs) are a family of zinc-dependent proteinases that are capable of cleaving all extra cellular matrix (ECM) substrates. Degradation of matrix is a key event in progression, invasion and metastasis of potentially malignant and malignant lesions of the head and neck. It might have an important polymorphic association at the promoter regions of several MMPs such as MMP-1 (-1607 1G/2G), MMP-2 (-1306 C/T), MMP-3 (-1171 5A/6A), MMP-9 (-1562 C/T) and TIMP-2 (-418 G/C or C/C). Tissue inhibitors of metalloproteinases (TIMPs) are naturally occurring inhibitors of MMPs, which inhibit the activity of MMPs and control the breakdown of ECM. Currently, many MMP inhibitors (MMPIs) are under development for treating different malignancies. Useful markers associated with molecular aggressiveness might have a role in prognostication of malignancies and to better recognize patient groups that need more antagonistic treatment options. Furthermore, the introduction of novel prognostic markers may also promote exclusively new treatment possibilities, and there is an obvious need to identify markers that could be used as selection criteria for novel therapies. The objective of this review is to discuss the molecular functions and polymorphic association of MMPs and TIMPs and the possible therapeutic aspects of these proteinases in potentially malignant and malignant head and neck lesions. So far, no promising drug target therapy has been developed for MMPs in the lesions of this region. In conclusion, further research is required for the development of their potential diagnostic and therapeutic possibilities.

Design and simulation of diatom-based microcantilever immunobiosensor for the early detection of Karnal bunt.

Fungal pathogen, Tilletia indica, the cause of Karnal bunt disease in wheat, is severely affecting the yield and grain quality, worldwide. Thus, strict quarantine regulations by most wheat growing countries have to be followed, leading to trade barriers for wheat export. The conventional methods being used for pathogen detection at symptomatic stage requires the germination of Tilletia spores for the processing of samples. Thus, it is time-consuming and expensive. This study proposes a simulated microcantilever-based piezoelectric biosensor for the early detection of T. indica. Four different materials, SiO2, SiC, Si3N4, and Poly Si, were used for the microcantilever design. Microcantilever was coated with siliceous frustules of diatom that provides high surface area and enhanced sensitivity for specific antibody against the antigen, T. indica. Ansys software was used for the simulation analysis. Simulation results showed that microcantilever beam of SiO2 length of 150 µm, width of 30 µm and thickness 1 µm enhanced the sensitivity by two times against the antibody in comparison to normal microcantilever beam. The results concluded that SiO2 with coated diatom is the best material for the microcantilever fabrication, thus, providing an excellent protocol for fabrication of microcantilever-based biosensor which is both cost- and time effective.

Development of a Diatom-Based Photoluminescent Immunosensor for the Early Detection of Karnal Bunt Disease of Wheat Crop.

In India, the major crop is wheat. Its production is severely hampered by seed-borne diseases such as smut and bunt which are responsible for the reduction of crop yield with poor grain quality. In the current study, an attempt was made to prepare a photoluminescence (PL)-based immunosensor for early detection of Karnal bunt (KB) disease. The KB disease-causing pathogen Tilletia indica was detected using functionalized diatom frustules as a sensing platform. The teliospore-covered platform, on exposure to light, showed enhanced intensity of PL in comparison to control. This response was directly proportional to the concentration of spores. For the development of a stable frustule-based immunosensor platform, gluteraldehyde was added for the covalent immobilization of the T. indica antibody onto amine-functionalized diatom substrates. Frustules of diatom consisting of a nanoporous three-dimensional biogenic silica material exhibit a unique property of emitting strong, visible blue PL under ultraviolet (UV) excitation. PL studies were done to reveal the specificity and binding of the conjugated diatom platform that will distinguish between the T. indica (complementary) and A. niger (noncomplementary) antigens. Four times better intensity of PL was observed against the complementary one in comparison to a noncomplementary setup (control). The immunocomplex frustule-based platform serves as a suitable sensor platform for early detection of KB.

Evaluation of carbon capture in competent microalgal consortium for enhanced biomass, lipid, and carbohydrate production.

Enrichment of carbon dioxide (CO2) in environment is a major factor for enhancement of global warming on Earth surface. Microalgal consortia play an important role in inhibiting the alarming fluxes of CO2 through sustainable mechanism of bioconversion of CO2 into biomass. In the present investigation, eight heterogeneous consortia of cyanobacteria and green algae such as MC1, MC2, MC3, MC4, MC5, MC6, MC7, and MC8 for the sustainable utilization of effective CO2 sequestration and biomass production were studied. Two factorial central composite designs (% CO2 and pH) were used for optimization of cellular morphology, growth, and development of consortia. The photosynthetic quantum yield of consortium MC8 was found to be maximum (0.61) in comparison with other consortia. The morphological and physiological behavior of the above consortium was analyzed under C, 5, 10, and 15% concentrations of CO2 resource capture in 250 mL BG-11+ medium. We have identified that 10% CO2 concentrated medium maximally promoted the cellular growth in terms of cell dimension, dried biomass, carbohydrate, and lipid contents in this consortium. As such, the elemental composition of carbon and carbon capturing capability was high at 10% CO2 concentration. However, further CO2 enrichment (15%) led to decline in growth and morphology of cell size as compared to control. The results indicate that the optimum CO2 enrichment in consortia exhibits potent commercial utilization for rapid biomass production and plays a distinguished role in global carbon sequestration and mitigation agent.

Composition and functional property of photosynthetic pigments under circadian rhythm in the cyanobacterium Spirulina platensis.

Circadian rhythm is an important endogenous biological signal for sustainable growth and development of cyanobacteria in natural ecosystems. Circadian effects of photosynthetically active radiation (PAR), ultraviolet-A (UV-A) and ultraviolet-B (UV-B) radiations on pigment composition have been studied in the cyanobacterium Spirulina platensis under light (L)/dark (D) oscillation with a combination of 4/20, 8/16, 12/12, 16/8, 20/4 and 24/24 h time duration. Circadian exposure of PAR + UV-A (PA) and PAR + UV-A + UV-B (PAB) showed more than twofold decline in Chl a, total protein and phycocyanin (PC) in light phase and significant recovery was achieved in dark phase. The fluorescence emission wavelength of PC was shifted towards lower wavelengths in the light phase of PAB in comparison to P and PA whereas the same wavelength was retrieved in the dark phase. The production of free radicals was accelerated twofold in the light phase (24 h L) whereas the same was retrieved to the level of control during the dark phase. Oxidatively induced damage was alleviated by antioxidative enzymes such as catalase (CAT), peroxidase (POD), superoxide dismutase (SOD) and ascorbate peroxidase (APX) in the light phase (0-24-h L) whereas the dark phase showed significant inhibition of the same enzymes. Similar characteristic inhibition of free radicals and recovery of PC was observed inside cellular filament after circadian rhythm of 24/24 h (L/D). Circadian exposure of P, PA and PAB significantly altered the synthesis and recovery of pigments that could be crucial for optimization and sustainable production of photosynthetic products for human welfare.

Direct sunlight enabled photo-biochemical synthesis of silver nanoparticles and their Bactericidal Efficacy: Photon energy as key for size and distribution control.

It is highly desirable to discover novel green synthesis methods for cheap and scalable synthesis of nanoparticles (NPs) to reduce the negative impact on the environment. But these approaches generally impose great challenge in controlling size, shape, and homogeneity of product NPs. Here in the present study, we report a novel approach enabling direct sunlight and oyster mushroom (Pleurotus citrinopileatus) extract for the photo-biochemical synthesis of Ag NPs. Sunlight of different wavelength was used to control the size and distribution of photo-biochemically produced NPs. Interestingly, it is observed that a smaller wavelength of sunlight produces smaller sized of NPs with a narrow size distribution. For examples; blue sunlight produces colloidal silver NPs with an average diameter of ~ 3.28 nm and 0.72 nm size distribution, while full sunlight produces comparatively larger sized (7.08 nm) NPs with wider (2.92 nm) size distribution. Since present approach uses only direct sunlight, freely available renewable energy source, a cheap biological extract as reducing and capping agent and cheap silver precursor, therefore it is an environment-friendly approach and can be used for the synthesis of NPs at industrial scale. Moreover, the size-dependent bactericidal effect has also been studied against pathogenic, Escherichia coli, bacteria. The minimum inhibitory concentration (MIC) 25 ppm and MBC 30 ppm have been observed for silver NPs of 3.28 nm average diameter.

Anticancer Potential of Steviol in MCF-7 Human Breast Cancer Cells.

OBJECTIVE: This study aimed to investigate the cytotoxicity, apoptosis induction, and mechanism of action of steviol on human breast cancer cells (Michigan Cancer Foundation-7 [MCF-7]). MATERIALS AND METHODS: Sulforhodamine-B assay was performed to analyze cytotoxic potential of Steviol whereas flow cytometer was used to analyze cell cycle, apoptosis, and reactive oxygen species generation. RESULTS: Studying the viability of cells confirms the IC50 of Steviol in MCF-7 cells which was 185 µM. The data obtained from fluorescence-activated cell sorter analysis reveal Steviol-mediated G2/M-phase arrest (P < 0.05) in addition to the presence of evident sub-G0/G1 peak (P < 0.05) in the MCF-7 cells, signifying the ongoing apoptosis. CONCLUSION: Thus, results suggest that induction of apoptosis in MCF-7 cells was due to dose-dependent effect of Steviol. Our first in vitro findings indicate Steviol as a promising candidate for the treatment of breast cancer. SUMMARY: Steviol remarkably inhibited the growth MCF-7 HBCCs in a dose dependent mannerIt abolishes cell cycle progression by arresting cells at G2/M phaseSteviol induces the cells to undergo apoptosisSteviol induces the cells to generate reactive oxygen species (ROS). Abbreviations used: MCF-7: Michigan Cancer Foundation-7; SRB: Sulforhodamine-B assay; FACS: Fluorescence-activated cell sorter; ROS: Reactive oxygen species; DNA: Deoxyribonucleic acid.

An analysis of phosphorylation sites in protein kinases from Leishmania.

Protein kinases are promising drug targets for Leishmaniasis. We have evaluated the phosphorylation potential of protein kinases in different species and strains of Leishmania. Phosphorylation potential of serine, threonine and tyrosine residues of kinases in Leishmania parasite were studied. The results indicate that some species specific residues of serine, threonine and tyrosine have a phosphorylation potential of 1 suggesting that these residues are important target sites in protein kinases based anti-leishmanial therapies.

Elucidating hydrogenase surfaces and tracing the intramolecular tunnels for hydrogenase inhibition in microalgal species.

Intramolecular tunnels are majorly attracting attention as possible pathways for entry of inhibitors like oxygen and carbon monoxide to the active sites of the enzymes, hydrogenases. The results of homology modeling of the HydSL protein, a NiFe-hydrogenase from Chlamydomonas reinhardtii and Chlorella vulgaris are presented in this work. Here we identify and describe molecular tunnels observed in HydSL hydrogenase enzyme systems. The possible determinant of the oxygen stability of already studied hydrogenases could be the lack of several intramolecular tunnels. The possible tunnels were traced out using MOLE 2 software, which showed several intramolecular pathways that may be connecting the active sites of the enzyme. The RMSD value showed a great deal of significance in the enzyme homology. This is the first report of its kind in which mapping of the intramolecular tunnels in the four-hydrogenase enzymes disclosed potential variations between designed models and acknowledged structures. We are seeking out the explanations for oxygen sensitivity of studied hydrogenases within the structure of intramolecular tunnels. Local and Global RMSD (Root mean square deviation) was calculated for models and templates, which showed value of 1.284 indicating a successful homology model. The tunnel tracing study by Mole 2 indicated two tunnels joined into one in C. reinhardtii model whereas C. vulgaris model showed one tunnel almost like two tunnels. Templates of both the A. vinosum and D. vulgaris hydrogenase consisted of six tunnels. For HydSL from Chlamydomonas and Chlorella Species the maximal potential was set to 250 kcal/mol (1,046 kJ/mol) and the positive potential areas were marked. Electrostatic studies define electrostatic potential (ESP) that help shuttle protons to the active site.

Evaluation of promising algal strains for sustainable exploitation coupled with CO2 fixation.

The photosynthetic activity of three microalgae, Chlamydomonas reinhardtii, Chlorella AU1, Scenedesmus AU1, and six cyanobacteria, Spirulina platensis, Anabaena cylindrica, Oscillatoria AU1, Nostoc muscurum, Synechococcus AU1, Synechocystis sp. PCC6803, was investigated. Strains S. platensis, Scenedesmus AU1 sp. and Chlorella AU1 sp. showed the highest fluorescence quenching than other strains tested. Thus, these were selected for CO2 mitigation analysis in a designed tubular photobioreactor system at 0.06%, 6%, 12%, 18% and 24% CO2 concentrations. Spirulina showed maximum biomass productivity of 1.03 g L(-1) d(-1) with the highest CO2 fixation rate of 0.678 g [Formula: see text] L(-1) d(-1) at 6% CO2 concentration. The maximum protein content (66.63%) was also achieved in Spirulina sp. at 6% CO2 concentration. Thus, Spirulina could be utilized as a source of protein supplement coupled with CO2 fixation. Maximum carbohydrate proportion (51.71%) was noted with Scenedesmus AU1 sp. at 12% CO2. Scenedesmus AU1 sp. also accumulated the maximum lipid content (25.07%) at 6% CO2 concentration, which was further analysed for biodiesel production. The extracted Scenedesmus oil was mainly rich in short chain fatty acids (C-16 : 0, C-18:1, C-18:2, C-18:3) which is an ideal combination for efficient biodiesel. Thus, this is vital in helping to choose Scenedesmus as a biodiesel feedstock, coupled with CO2 fixation.

Isolation and in-silico characterization of Peroxidase isoenzymes from Wheat (Triticum aestivum) against Karnal Bunt (Tilletia indica).

To investigate the role of Peroxidase and its physiological significance under Karnal Bunt (KB) were determined in resistant (HD-29) and susceptible genotype (WH-542) of wheat during different developmental stages. The enzymes were expressed constitutively in both the susceptible and resistant genotype. In gel assay and differential expression analysis of POD was significantly higher (p >0.05) in Sv and S2, than the S1 and S3 stages. in silico analysis of Peroxidase for eg. physico-chemical properties, secondary structural features and phylogenetic classification for comparative analysis. Motif and Domain analysis of Peroxidase by MEME, to be important for the biological functions, and studies of evolution. Our results clearly indicate that the enhanced expression of POD at the WS2 stage, which reinforces its role in stage dependent immunity against Karnal bunt and role of POD metabolism provides genotype and stage dependant structural barrier resistance in wheat against KB.

Analysis of proteins involved in the production of MAA׳s in two Cyanobacteria Synechocystis PCC 6803 and Anabaena cylindrica.

Mycosporine- like amino acids (MAAs) are small (<400Da), colourless, water soluble compounds composed of cyclohexenone or cyclohexinimine chromophere conjugated with the nitrogen substituent of amino acid or its amino alcohol. These compounds are known for their UV- absorbing role in various organisms and seem to have evolutionary significance. The biosynthesis of MAAs is presumed to occur via the first part of shikimate pathway. In the present work two cyanobacteria Synechocystis PCC 6803 and Anabaena cylindrica were tested for their ability to synthesize MAAs and protein involved in the production of MAAs. It was found that protein sequence 3-phosphoshikimate 1-carboxyvinyltransferase is involved in producing mycosporine glycine in Synechocystis PCC 6803 and 3-dehydroquinate synthase is involved for producing shinorine in Anabaena cylindrica. Phylogenetic and bioinformatic analysis of Mycosporine like amino acid producing protein sequence of both cyanobacterial species Synechocystis PCC 6803 and Anabaena cylindrica provide a useful framework to understand the relationship of the different forms and how they have evolved from a common ancestor. These products seem to be conserved but the residues are prone to variation which might be due the fact that different cyanobacteria show different physiological process in response of Ultraviolet stress.

Red luminescent manganese-doped zinc sulphide nanocrystals and their antibacterial study.

Water soluble, uniform-sized ZnS:Mn2+ nanocrystals (NCs) have been prepared using a simple co-precipitation method with a methanol and water binary mixture as a reaction medium. The structure of the prepared ZnS:Mn2+ NCs is cubic with a mean size distribution of 3-5 nm. Photoluminescence (PL) studies showed emission at ∼612 nm, which is 22 nm red shifted as compared with the reported literature. This red shift could be attributed to the observed distortion in the imaged lattice plane. The capping effect of pepsin, citric acid and biotin on the optical properties of ZnS:Mn2+ NCs has been examined and the maximum enhancement in PL Intensity was found in the case of biotin. The synthesised ZnS:Mn2+ NCs were characterized by X-ray Diffraction (XRD), transmission electron microscopy (TEM), X-ray photoemission spectroscopy (XPS) for investigation of their structural properties. Because of the high PL intensity, biotin capped ZnS:Mn2+ NCs were further investigated for their anti-bacterial activity against gram negative and gram positive bacteria. These NCs show broad spectrum antibacterial activity against both types of bacteria having an MIC value of 100 ng ml-1 for B. subtilis.

Defining binding efficiency and specificity of auxins for SCF(TIR1/AFB)-Aux/IAA co-receptor complex formation.

Structure-activity profiles for the phytohormone auxin have been collected for over 70 years, and a number of synthetic auxins are used in agriculture. Auxin classification schemes and binding models followed from understanding auxin structures. However, all of the data came from whole plant bioassays, meaning the output was the integral of many different processes. The discovery of Transport Inhibitor-Response 1 (TIR1) and the Auxin F-Box (AFB) proteins as sites of auxin perception and the role of auxin as molecular glue in the assembly of co-receptor complexes has allowed the development of a definitive quantitative structure-activity relationship for TIR1 and AFB5. Factorial analysis of binding activities offered two uncorrelated factors associated with binding efficiency and binding selectivity. The six maximum-likelihood estimators of Efficiency are changes in the overlap matrixes, inferring that Efficiency is related to the volume of the electronic system. Using the subset of compounds that bound strongly, chemometric analyses based on quantum chemical calculations and similarity and self-similarity indices yielded three classes of Specificity that relate to differential binding. Specificity may not be defined by any one specific atom or position and is influenced by coulomb matrixes, suggesting that it is driven by electrostatic forces. These analyses give the first receptor-specific classification of auxins and indicate that AFB5 is the preferred site for a number of auxinic herbicides by allowing interactions with analogues having van der Waals surfaces larger than that of indole-3-acetic acid. The quality factors are also examined in terms of long-standing models for the mechanism of auxin binding.