An Investigation of Electrospun Clerodendrum phlomidis Leaves Extract Infused Polycaprolactone Nanofiber for In Vitro Biological Application

The in vitro antibacterial, anticancer, and antioxidant activities of a few plant extracts were widely known for decades, and they were used for application in the conventional way. Specifically, electrospun nanofibrous mats have recently exhibited great antibacterial, anticancer, and antioxidant activities. The herbal extracts infused into these formations are expected to have a more efficient and integrated effect on in vitro biological applications. The purpose of this study is to develop polycaprolactone- (PCL-) based nanofiber mats that are infused with a traditional plant extract using Clerodendrum phlomidis leaves to improve the synthesized nanofibers' antibacterial, anticancer, and antioxidant efficacy. This study examined the morphology, thermal properties, mechanical properties, structure, and in vitro drug release studies of electrospun nanofibers. Antibacterial, anticancer, and antioxidant activities of the electrospun nanofibrous mats were also studied. The HRTEM and FESEM pictures of PCL and PCL-CPM nanofibers provide that smooth, defect-free, and homogeneous nanofibers were found to be 602.08 ± 75 nm and 414.15 ± 82 nm for PCL and PCL-CPM nanofibers, respectively. The presence of Clerodendrum phlomidis extract in the electrospun nanofibers was approved by UV-visible and FTIR spectroscopy. The incorporation of Clerodendrum phlomidis extract to nanofiber mats resulted in substantial antibacterial activity against bacterial cells. PCL-CPM mats exposed to oral cancer (HSC-3) and renal cell carcinoma (ACHN) cell lines displayed promising anticancer activity with less than 50% survival rate after 24 h of incubation. 2,2-Diphenyl-1-picrylhydrazyl (DPPH) assay performed on PCL-CPM nanofibers revealed the antioxidant scavenging activity with maximum inhibition of 34% suggesting the role of the secondary metabolites release from scaffold. As a result, the findings of this study revealed that Clerodendrum phlomidis extract encapsulating PCL electrospun nanofibers has a high potential for usage as a biobased antibacterial, anticancer, and antioxidant agent.

Tuning of Carbon Microspheres and Graphene Structures with Hetero Atoms for Organic Dye Degradation and Heavy Metal Remediation - Influence of Fructose as a Precursor

In today’s context, there is a tremendous potential for the design of smart nanomaterials of carbon origin for multi-dimensional applications. The role-play of precursor is significant in the design of nanometric carbon materials apart from other experimental parameters. Correlation of the synthetic methodology, the microstructure of the product helps to tune and widen the applications aspect. The present study aimed to tune the simple ketose (reducing monosaccharide) of fructose to functionalize (with O, N, and S atoms) carbon layers, microspheres of carbon, to optimize the experimental conditions, and to establish the mechanism involved in the process. The study further explored the catalytic ability of the carbon samples in the degradation of thiazine and xanthene-based textile dyes and the sensing of heavy metal ions of chromium and copper. A simple hydrothermal process, fructose as a precursor, alkaline pH, and appropriate calcination temperature provided micro and nanostructures of carbon viz. carbon microspheres (CMs), graphene oxide (GO), sulfur doped graphene oxide (S-GO), and nitrogen-doped reduced graphene oxide (N-rGO). In this study a simple mechanism for the conversion process is suggested. Further, the results of the preliminary screening study on the catalytic ability of the sulfur and nitrogen-doped graphene samples in the presence of UV and Visible light upon the degradation of methylene blue (MB), methyl orange (MO), Rhodamine-B (Rh-B) dyes were satisfactory. The adsorbent and the ion exchange capacity of the carbon microspheres were found to be excellent. The results of the study will contribute positively to the treatment and management of industrial wastewater.

Assessment of Patients with Periorbital Melanosis for Hyperinsulinemia and Insulin Resistance

Background:

Periorbital melanosis (PM) is one of the most common dermatological condition seen in routine practice. Several cutaneous markers such as acanthosis nigricans have been associated with insulin resistance (IR). However, the association of PM with IR needs to be substantiated.

Objective:

The objective of the study is to evaluate the association of circulating adipokines and IR with PM.

Materials and Methods:

In this cross-sectional study, we recruited 100 patients with PM and 100 age- and gender-matched healthy controls. The serum levels of leptin, adiponectin, fasting glucose, fasting insulin, insulin-like growth factor-1 (IGF-1), homeostatic model assessment of insulin resistance (HOMA-IR), and leptin: adiponectin ratio (L/A ratio) were assayed.

Results:

The serum levels of leptin, fasting glucose, fasting insulin, HOMA-IR, L/A ratio were significantly higher in patients with PM as compared to controls. The serum levels of adiponectin were significantly lower in cases as compared to controls. On multivariate regression analysis, leptin, adiponectin, and HOMA-IR were found to be significant, even after adjusting for BMI, blood pressure and LDL and HDL cholesterol.

Conclusion:

Our findings suggest that patients with PM have hyperinsulinemia, IR, and elevated L/A ratio. PM as a marker of IR in adults may help in identifying patients early and thus aid in the early prevention and management of the disease.

Hemostatic potential of latex proteases from Tabernaemontana divaricata (L.) R. Br. ex. Roem. and Schult. and Artocarpus altilis (Parkinson ex. F.A. Zorn) Forsberg

Pharmacological properties exhibited by latex of plants are due to various biologically active compounds including several proteolytic enzymes. Present study evaluates hemostatic potential of Tabernaemontana divaricata and Artocarpus altilis from Apocynaceae and Moraceae families respectively. The latex of these plants were initially subjected to dialysis and crude extracts were estimated for proteolytic activity using casein as the substrate. Mean caseinolytic activity for 100 μg of latex protein was found to be 56.16 ± 0.57 and 45 ± 0.3 U/h for T. divaricata and A. altilis respectively. Caseinolytic activity by both the plant extracts was higher than standard proteases, papain and trypsin. However the difference was significant (p < 0.05) with papain alone. Crude enzymes (CE) from both plants exhibited coagulant activity on human platelet poor plasma by recalcification time. A significant reduction in clotting time was exhibited by T. divaricata compared to A. altilis (p < 0.05). These results were further substantiated with fibrinogen agarose plate assay. Crude enzyme of both plants also hydrolyzed blood clot. Mean % of thrombolysis by T. divaricata was 80.75 ± 1.2 and that of A. altilis was 70.24 ± 1.52. Inhibition studies confirmed cysteine protease nature of CE. Comparative analysis revealed T. divaricata to be the best among the two for its hemostatic potential. This study scientifically validates the use of latex from these plants in the management of fresh cuts or wounds.

Development of a VIGS vector based on the β-satellite DNA associated with bhendi yellow vein mosaic virus

Bhendi yellow vein mosaic virus (BYMV) is a monopartite begomovirus with an associated β-satellite. βC1 ORF encoded by the β-satellite is the symptom determinant and a strong suppressor of post transcriptional gene silencing. To create a virus induced gene silencing vector based upon the β-satellite associated with BYVMV the βC1 ORF was replaced with multiple cloning sites. GFP transgene and plant endogenous genes Su, PDS, PCNA and AGO1 were cloned into β-satellite based VIGS vector. GFP expression was silenced in the GFP expressing transgenic 16c Nicotiana benthamiana plants infiltrated with VIGS vector carrying GFP gene inside. N. benthamiana plants infiltrated with the VIGS vector harboring the endogenous genes Su, PDS, PCNA and AGO1 produced the phenotypic symptoms yellowing of the veins, photobleaching of the veins, stunting of the plant and upward leaf curling, respectively. Real time PCR analyses revealed a reduction in the levels of the corresponding transgene or endogenous target mRNA. The β-satellite based VIGS vector was able to silence the target genes effectively. Hence, BYVMV β-satellite based VIGS vector can be used in functional genomics studies.

Potential contribution of monoamine oxidase a gene variants in ADHD and behavioral co-morbidities: scenario in eastern Indian probands

Attention deficit hyperactivity disorder (ADHD) is the most frequently diagnosed behavioral disorder in children with a high frequency of co-morbid conditions like conduct disorder (CD) and oppositional defiant disorder (ODD). These traits are controlled by neurotransmitters like dopamine, serotonin and norepinephrine. Monoamine oxidase A (MAOA), a mitochondrial enzyme involved in the degradation of amines, has been reported to be associated with aggression, impulsivity, depression, and mood changes. We hypothesized that MAOA can have a potential role in ADHD associated CD/ODD and analyzed 24 markers in a group of Indo-Caucasoid subjects. ADHD probands and controls (N = 150 each) matched for ethnicity and gender were recruited following the Diagnostic and Statistical Manual for Mental Disorders-IV. Appropriate scales were used for measuring CD and ODD traits. Markers were genotyped by PCR-based methods and data obtained analyzed using the Cocaphase program under UNPHASED. Only eight markers were found to be polymorphic. rs6323 "G" allele showed higher frequencies in ADHD (P = 0.0023), ADHD + CD (P = 0.03) and ADHD + ODD (P = 0.01) as compared to controls. Haplotype analysis revealed statistically significant difference for three haplotypes in ADHD cases (P < 0.02). Statistically significant differences were also noticed for haplotypes in ADHD + CD and ADHD + ODD cases (P < 0.01). LD analysis showed significant variation in different groups. Multidimensionality reduction analysis showed independent as well as interactive effects of markers. Genotypes showed correlation with behavioral problems in ADHD and ADHD + CD. We interpret that MAOA gene variants may contribute to the etiology of ADHD as well as associated co-morbid CD and ODD in this ethnic group.

The C2 protein of Bhendi yellow vein mosaic virus plays an important role in symptom determination and virus replication

Bhendi yellow vein mosaic virus (BYVMV) that causes bhendi yellow vein mosaic disease is a monopartite begomovirus with an associated betasatellite. Previous studies have shown that C2 protein of BYVMV acts as a suppressor of post transcriptional gene silencing, activates transcription, localizes to nucleus, and interacts with karyopherin α. To probe the role of C2 in symptom determination and virus replication, the infectious clones of BYVMV containing two stop codons in the C2 ORF were created and used for infection studies. The Nicotiana benthamiana plants infiltrated with the infectious clones harboring stop codons in the C2 ORF did not develop any symptoms unlike plants infiltrated with wild-type BYVMV. Southern blotting and real time PCR analysis revealed that the viral load was reduced drastically in the plants infected with BYVMV containing the nontranslatable version of C2 ORF. However, there was a recovery in viral DNA replication, when co-infiltrated with wild-type betasatellite. Hence we conclude that the C2 protein of BYVMV plays an important role in symptom determination and viral DNA replication.

Instabilities of a free bilayer flowing on an inclined porous medium

The instabilities of a free bilayer flowing on an inclined Darcy-Brinkman porous layer have been explored. The bilayer is composed of a pair of immiscible liquid films with a deformable liquid-liquid interface and a liquid-air free surface. An Orr-Sommerfeld analysis of the governing equations and boundary conditions uncovers that this configuration can be unstable by a pair of long-wave interfacial modes at the free surface and at the interface together with a couple of finite wave-number shear modes originating from the inertial influences at the liquid layers. In particular, one of the shear modes originates beyond a threshold flow rate owing to the slippage at the porous-liquid interface and is found to be the dominant one even when the porous medium is moderately thin, porous, and permeable. The strength of the porous media mediated mode (a) grows with increase in porosity, (b) grows and then remains invariant with increase in thickness, and (c) initially grows and then decays with increase in the permeability of the porous layer. Further, the presence of a lower layer with smaller viscosity and a thicker upper layer is found to facilitate the growth of this newly identified porous media mode. Importantly, beyond a threshold upper to lower thickness and viscosity ratios and the angle of inclination the porous media mode dominates over all the other interfacial or shear modes, highlighting its importance in the bilayer flows down an inclined porous medium. The study showcases the importance of a porous layer in destabilizing a free bilayer flow down an inclined plane, which can be of importance to improve mixing, emulsification, and heat and mass transfer characteristics in the microscale devices.

Expression, purification and molecular modeling of the NIa protease of Cardamom mosaic virus

The NIa protease of Potyviridae is the major viral protease that processes potyviral polyproteins. The NIa protease coding region of Cardamom mosaic virus (CdMV) is amplified from the viral cDNA, cloned and expressed in Escherichia coli. NIa protease forms inclusion bodies in E.coli. The inclusion bodies are solubilized with 8 M urea, refolded and purified by Nickel-Nitrilotriacetic acid affinity chromatography. Three-dimensional modeling of the CdMV NIa protease is achieved by threading approach using the homologous X-ray crystallographic structure of Tobacco etch mosaic virus NIa protease. The model gave an insight in to the substrate specificities of the NIa proteases and predicted the complementation of nearby residues in the catalytic triad (H42, D74 and C141) mutants in the cis protease activity of CdMV NIa protease.

Molecular modeling and conformational analysis of native and refolded viral genome-linked protein of cardamom mosaic virus

The viral genome-linked protein (VPg) of Potyviruses is covalently attached to the 5' end of the genomic RNA. Towards biophysical characterization, the VPg coding region of Cardamom mosaic virus (CdMV) was amplified from the cDNA and expressed in E. coli. Most of the expressed VPg aggregated as inclusion bodies that were solubilized with urea and refolded with L-arginine hydrochloride. The various forms of CdMV VPg (native, denatured and refolded) were purified and the conformational variations between these forms were observed with fluorescence spectroscopy. Native and refolded CdMV VPg showed unordered secondary structure in the circular dichroism (CD) spectrum. The model of CdMV VPg was built based on the crystal structure of phosphotriesterase (from Pseudomonas diminuta), which had the maximum sequence homology with VPg to identify the arrangement of conserved amino acids in the protein to study the functional diversity of VPg. This is the first report on the VPg of CdMV, which is classified as a new member of the Macluravirus genus of the Potyviridae family.

A simple and efficient method for agroinfection of Vernonia cinerea with infectious clones of Vernonia yellow vein virus

Vernonia yellow vein virus (VeYVV) is a distinct monopartite begomovirus associated with a satellite DNA β. After constructing dimers of both DNA A and DNA β in binary vectors, a number of infection methods were attempted. However, only a modified stem-prick method produced up to 83% infection in the natural host Vernonia cinerea, thus, fulfilling the Koch's postulate. The presence of the viral DNA in the agroinfected plants was confirmed by rolling circle amplification (RCA), followed by Southern hybridization. DNA β induces typical symptoms of Vernonia yellow vein disease (VeYVD) when co-agroinoculated with the begomovirus to Vernonia and also leads to the accumulation of DNA A systemically. VeYVV represents a new member of the emerging group of monopartite begomoviruses requiring a satellite component for symptom induction.

Nutritional, sensory and physical analysis of pumpkin flour incorporated into weaning mix

The objective of this study was to develop a cereal-pulse complementary food fortified with different concentrations of pumpkin powder (Cucurbita moschata), and to analyse its sensory and physic-chemical parameters. Fresh pumpkins(Cucurbita moschata) were procured from the market and dehydrated and powdered in the laboratory. Sorghum (Sorghum vulgare) and whole green gram (Vigna radiate) were germinated, dried, pulverised and combined with powdered rice (Oryza sativa) in the ratio of 2:1:1. Pumpkin powder was added to this mixture at 10%, 20% and 30% variations. The complementary weaning food mix was subjected to sensory analysis (appearance, colour, flavour, texture and overall acceptability) by semi-trained panelists. The mix was analysed for its moisture, energy, protein, fat, carbohydrates, fibre, beta-carotene and anti-oxidant content. Nutritional analysis of the weaning mix demonstrated that there was a significant increase in the protein, fibre, carbohydrate and antioxidant levels with an increase in concentration of pumpkin powder. The sensory analysis revealed that the complementary food mix with 20% pumpkin powder fortification had good sensory qualities.

Electrified film on a porous inclined plane: dynamics and stability

The time evolution of a thin conducting liquid film flowing down a porous inclined substrate is investigated when an electric field acts normal to the substrate. It is assumed that the flow through the porous medium is governed by Darcy's law together with Beavers-Joseph condition. Under the assumption of small permeability relative to the thickness of the overlying fluid layer, the flow is decoupled from the filtration flow through the porous medium. A slip condition at the bottom is used to incorporate the effects of the permeability of the substrate. From the set of exact averaged equations derived using integral boundary method for the film thickness and for the flow rate, a nonlinear evolution equation for the film thickness is derived through a long-wave approximation. A linear stability analysis of the base flow is performed and the critical Reynolds number is obtained. The results reveal that the substrate porosity in general destabilizes the liquid film flow and the presence of the electric field enhances this destabilizing effect. A weakly nonlinear stability analysis divulges the existence of supercritical stable and subcritical unstable zones in the wave number/Reynolds number parameter space and the results demonstrate how the neutral curves change as the intensity of the electric filed or the permeability of the porous medium is varied. The numerical solution of the nonlinear evolution equation in a periodic domain reveals that the base flow yields to surface structures that are either time independent waves of permanent form that propagate or time-dependent modes that oscillate slightly in the amplitude. Further, it is observed that the shape and amplitude of long-time waveforms are influenced by the permeability of the porous medium as well as by the applied electric field. The results reveal that the destabilization induced by the electric field in an otherwise stable film over a porous medium is exhibited in the form of traveling waves of finite amplitude. The presence of the porous substrate promotes the oscillatory behavior of the long-time waveform; however, the electric field has a tendency to suppress this oscillatory behavior.

Molecular characterization of a distinct begomovirus species from Vernonia cinerea and its associated DNA-beta using the bacteriophage Phi 29 DNA polymerase

Vernonia cinerea plants with yellow vein symptoms were collected around crop fields in Madurai. A portion (550 bp) of the AV1 gene amplified using degenerate primers from the total DNA purified from diseased leaf sample was cloned and sequenced. Specific primers derived from the above sequence were used to amplify 2,745 nucleotides with the typical genome organization of begomoviral DNA A (EMBL Accession No. AM182232). Sequence comparison with other begomoviruses revealed the greatest identity (82.4%) with Emilia yellow vein virus (EmYVV-[Fz1]) from China and less than 80% with all other known begomoviruses. The International Committee on Taxonomy of Viruses (ICTV) has therefore recognized Vernonia yellow vein virus (VeYVV) as a distinct begomovirus species. Conventional PCR could not amplify the DNA B or DNA beta from the diseased tissue. However, the beta DNA (1364 bp) associated with the disease was obtained (Accession No. FN435836) by the rolling circle amplification-restriction fragment length polymorphism method (RCA-RFLP) using Phi 29 DNA polymerase. Sequence analysis shows that DNA beta of VeYVV has the highest identity (56.8%) with DNA beta of Sigesbeckia yellow vein Guangxi betasatellite (SibYVGxB-[CN: Gx111:05]) and 56-53% with DNA beta associated with other begomoviruses. This is the first report of the molecular characterization of VeYVV from V. cinerea in India. The complete molecular characterization, phylogenetic analysis, and putative recombination events in VeYVV are reported.

Stability of collagen in the presence of 3,4-dihydroxyphenylalanine (DOPA)

Many cross-linking agents for collagen are available with varying levels of toxicity and some are in use in biomedical implants of collagen. L-DOPA (3,4-dihydroxyphenylalanine), a neurotransmitter, is a naturally present compound in the living system and is the target in therapeutic strategy of Parkinson's disease. This work reports the effect of the neurotransmitter DOPA on the stability of collagen solution using circular dichroism (CD), fluorescence spectroscopy, melting and shrinkage temperature. Collagen solution treated with various concentrations of DOPA ranging from 10(-2) to 10(-5)M was analyzed using fluorescence and CD spectra. When collagen was treated with DOPA, the intensity of emission was found to increase indicating the possibility of interaction of DOPA with collagen and maximum emission intensity was observed between 10(-3) and 10(-4)M for L-DOPA and DL-DOPA, respectively. CD studies show possible aggregation of collagen even in the presence of low concentrations of DOPA. The shrinkage temperature of DOPA treated collagen fibres was experimentally determined to be 69+/-1 degrees C. The melting temperature of DOPA cross linked collagen solution also exhibited a significant increase from 35 to 40 degrees C (+/-0.1) (P<0.05). The experimental results suggest that the optimum concentration for cross linking collagen with DOPA ranges between 10(-3) and 10(-4)M. Thus, DOPA may be a useful stabilizing agent for collagen for biomedical applications.

Optimized expression, solubilization and purification of nuclear inclusion protein b of cardamom mosaic virus

All RNA viruses encode an RNA-dependent RNA polymerase (RdRP) that is required for replication of the viral genome. Nuclear inclusion b (NIb) gene codes for the RdRp in Potyviridae viruses. In this study, expression, solubilization and purification of NIb protein of Cardamom mosaic virus (CdMV) is reported. The objective of the present study was to express and purify the NIb protein of CdMV on a large scale for structural characterization, as the structure of the RdRp from a plant virus is yet to be determined. However, the expression of NIb protein with hexa-histidine tag in Escherichia coli led to insoluble aggregates. Out of all the approaches [making truncated versions to reduce the size of protein; replacing an amino acid residue likely to be involved in hydrophobic intermolecular interactions with a hydrophilic one; expressing the protein along with chaperones; expression in Origami cells for proper disulphide bond formation, in E. coli as a fusion with maltose-binding protein (MBP) and in Nicotiana tabacum] to obtain the RdRp in a soluble form, only expression in E. coli as a fusion with MBP and its expression in N. tabacum were successful. The NIb expressed in plant or as a fusion with MBP in E. coli can be scaled up for further work.

Stability of collagen with polyols against guanidine denaturation

The effect of polyol osmolytes such as erythritol, xylitol and sorbitol on the protection of collagen against guanidine hydrochloride (GdmCl) was studied using circular dichroism and fluorescence spectroscopy. Collagen was denatured by various concentrations of GdmCl in the presence of polyols. The absorbance was high for GdmCl treated collagen than native and polyols treated analogue. Fluorescence emission properties were studied at the excitation wavelength of 235 nm. The emission wavelength is red shifted from 308 to 370 nm for GdmCl treated collagen with polyols. Increasing the concentration of GdmCl did not affect the peak position. CD studies proved that the aggregation of collagen in the presence of lower concentrations of GdmCl. At higher concentrations of GdmCl due to the loss of secondary structure no clear CD spectra were observed. This shows that the unfolding of collagen is closely related to GdmCl concentrations. The ability of the polyols to protect collagen against guanidine denaturation decreased in order from erythritol to xylitol to sorbitol. The presence of OH group in the solvent structure is important for stabilization of collagen due to the formation of additional stabilizing hydrogen bonds.

Sequence and recombination analyses of the geminivirus replication initiator protein

The sequence motifs present in the replication initiator protein (Rep) of geminiviruses have been compared with those present in all known rolling circle replication initiators. The predicted secondary structures of Rep representing each group of organisms have been compared and found to be conserved. Regions of recombination in the Rep gene and the adjoining 5' intergenic region (IR)of representative species of Geminiviridae have been identified using Recombination Detection Programs. The possible implications of such recombinations on the increasing host range of geminivirus infections are discussed.

Differential roles of C4 and betaC1 in mediating suppression of post-transcriptional gene silencing: evidence for transactivation by the C2 of Bhendi yellow vein mosaic virus, a monopartite begomovirus

Bhendi yellow vein mosaic disease (BYVMD) is caused by the association of a DNA beta satellite with a begomovirus component. The begomovirus component has two promoters, one in the virion sense (V-sense) and the other in the complementary sense (C-sense) in the intergenic region (IR). To study the promoter activities of V-sense and C-sense promoters, mGFP gene fusion was made downstream to the promoters. Transient and stable expressions in N. benthamiana leaves showed significant GFP expression under C-sense promoter whereas the expression under the V-sense promoter was very weak in the absence of the transactivator C2. Untransformed N. benthamiana plants were agroinfiltrated with binary vector constructs containing V-sense-GFP alone or along with C1, C2, C4, V1, V2 or betaC1 (in both sense and antisense orientations) to understand the roles of these gene products in transactivation and/or suppression of post-transcriptional gene silencing (PTGS). The results showed strong suppression of gene silencing activities for C4 and betaC1 but a weak activity for C2. The suppression activities were also confirmed using gfp-silenced GFP16c/GFPi plants by agroinfiltration and agroinoculation. The expression of C4 and betaC1 as transgenes produced abnormal phenotypic growth compared to the other viral genes mentioned above, further supporting their suppressor function.

Protein-protein interactions and nuclear trafficking of coat protein and betaC1 protein associated with Bhendi yellow vein mosaic disease

Bhendi yellow vein mosaic disease (BYVMD) is caused by a complex consisting of a monopartite begomovirus BYVMV and a satellite DNA beta component. BYVMV represents a new member of the emerging group of monopartite begomoviruses requiring a satellite component for symptom induction. Here we report the results of the transient expression of green fluorescent protein (GFP) fused with the betaC1 and coat protein (CP) coding regions, in the epidermal cells of Nicotiana benthamiana. GFPCP was found to be targeted into the nucleus whereas GFPbetaC1 was localized towards the periphery of the cell. The sub-cellular localization of the betaC1 protein has been compared with that of the CP in yeast cells using a genetic system for detection of protein nuclear import and export. Expression of betaC1 ORF in transgenic N. benthamiana under the control of the Cauliflower mosaic virus 35S promoter produced severe developmental abnormalities in the plant, like distorted stem, leaves and stunting of the plant. We also present the results on the interaction of CP and betaC1 proteins using yeast two hybrid analysis, suggesting a collaborative role in the inter- and intracellular dynamics of BYVMD.

Freshwater lakes--a potential source for aquaculture activities--a model study on Perumal Lake, Cuddalore, Tamil Nadu

The freshwater Perumal lake located at Cuddalore was assessed for its suitability and potential for aquaculture practices. Various hydrobiological parameters determined reveals that the various physicochemical characteristics are with in normal range of values. The DO level, BOD and COD values determined in the lake revealed the consequences of community activities and pollution possibilities. The primary productivity data revealed maximum productivity during March which infer that the lake is unaffected by anthropogenic disturbance and community contamination. The bacterial count remained higher during the monsoon periods, which characterize profuse rainfall and storm water discharge into the lake. The microfauna includes zooplankter such as cladocerans, copepods, rotifers and ostracods. Benthos include carps, catfishes, mullets and prawns. The above study revealed that the various parameters in the lake conform to the levels suited for freshwater fish culture and represents a resource for scientific management.

Refolding, purification and characterization of replication-initiator protein from soybean-infecting geminivirus

The replication-initiator protein (Rep) from a soybean-infecting geminivirus was overexpressed in E. coli as a fusion protein with maltose binding protein (MBP). In spite of the presence of the highly soluble MBP as the fusion partner, the overexpressed MBP-Rep fusion protein formed insoluble inclusion bodies. The protein was solubilized from the inclusion bodies and refolded. The refolded MBP-Rep protein was purified using ion exchange and amylose affinity chromatography. The activity of the purified MBP-Rep was assessed using an in vitro cleavage assay. Soluble and stable MBP-Rep protein was obtained in high abundance, providing the feasibility of large-scale production of active Rep protein for functional characterization and X-ray crystallographic structure determination.

Structural influence of mono and polyhydric alcohols on the stabilization of collagen

In the present study, solvents effects on the structure of collagen have been examined by circular dichroism and their interfacial tension at glass/liquid and Teflon/liquid. Changes in the conformations of the protein have been analyzed after equilibration with aqueous solutions of monohydric and polyhydric alcohols like methanol, ethanol, n-propanol, propane-2-diol and glycerol. The results from viscosity and Circular dichroism (CD) spectra suggest a clear distinction in the structural changes for collagen with monohydric alcohols as against polyhydric ones. The surface tension and interfacial tension at glass (high surface energy, HFSE) and Teflon (Low surface energy, LSFE) reflect similar differences between the monohydric and polyhydric alcohols. Studies on the interfacial energy of the adsorbed protein at glass/solution interface compared to that of Teflon/solution interface show that the water structure near glass gets perturbed leading to an increase in the average free energy of the bulk water phase and a reduction in hydrophobic effect near the glass. The results suggest that the different solvents alter the hydrophobic effect on the hydrated protein to different extent and thus influence folding equilibrium of the protein without directly interacting with it. Polyhydric alcohols seem to favor the native collagen structure while monohydric alcohols enhance it.

Molecular characterization of two soybean-infecting begomoviruses from India and evidence for recombination among legume-infecting begomoviruses from South [corrected] South-East Asia

The complete nucleotide sequences of two soybean-infecting begomoviruses have been determined from central and southern parts of India. Sequence analyses show that the isolate from central India is a strain of Mungbean yellow mosaic India virus (MYMIV) and the southern Indian isolate is a strain of Mungbean yellow mosaic virus (MYMV). Multiple DNA B components could be detected with the soybean strain of Mungbean yellow mosaic virus species. The nucleotide sequence similarity between the DNA A components of the two isolates is higher (82%) than that between the corresponding DNA B components (71%). Analyses of the common region of the genomic components of these two virus isolates indicate considerable divergence in the origin of replication (ori), which did not impair their infectivity as demonstrated for the central Indian isolate by agroinfection with partial tandem repeats (PTRs) of the genomic components. Detailed sequence and phylogenetic analyses reveal the distribution and possible recombination events among legume-infecting begomoviruses from South-East Asia.

Structure and conformation of intramolecularly cross-linked collagen

This work reports the effects of cross-linking agent like formaldehyde (HCHO) and glutaraldehyde (GA) on monomeric collagen and its conformational stability using circular dichroism. The nature of the bonds formed and the stability of the cross-links introduced vary with the aldehyde. The amount of HCHO required is four times greater than GA to induce similar changes in the molar ellipticity. This is due to the structural changes of collagen-aldehyde reaction. The change in the molar ellipticity and Rpn ratio for HCHO and GA treated collagen suggest possible aggregation of collagen molecule. The relative viscosity of native and aldehyde treated collagen was measured and correlated to the changes seen in the CD spectra. The small amount of aldehydes are needed to induce changes in the conformational stability of collagen. This can be applied to the biomaterial and biomedical application.

Changes in polyamine contents and arginine decarboxylase activity associated with elongation growth of hypocotyls in Rhizophora apiculata Bl

Changes in polyamine (putrescine, spermidine, spermine) contents and arginine decarboxylase activity in three different regions of developing hypocotyls of Rhizophora apiculata Bl. were analyzed. Among the three polyamines, spermidine was present in higher quantities than either putrescine or spermine. Spermine occurred in the lowest quantities. Spermidine declined rapidly with the age of the hypocotyl. In contrast, a marked increase in putrescine was observed with the age of the hypocotyl. Arginine decarboxylase activity increased during the various developmental stages of hypocotyl growth, particularly in the final stage. The results suggest that putrescine plays a major role in the growth of the hypocotyl as evidenced by simultaneous increase in the content of putrescine and arginine decarboxylase activity.Key words: arginine decarboxylase, elongation, hypocotyls, polyamines, Rhizophora apiculata.

High genetic diversity in the coat protein and 3′ untranslated regions among geographical isolates ofCardamom mosaic virus from south India

A survey was conducted to study the biological and genetic diversity of Cardamom mosaic virus (CdMV) that causes the most widespread disease in the cardamom growing area in the Western Ghats of south India. Six distinct subgroups were derived based on their symptomatology and host range from the sixty isolates collected. The serological variability between the virus isolates was analysed by ELISA and Western blotting. The 3 terminal region consisting of the coat protein (CP) coding sequence and 3 untranslated region (3 UTR) was cloned and sequenced from seven isolates. Sequence comparisons revealed considerable genetic diversity among the isolates in their CP and 3 UTR, making CdMV one of the highly variable members of Potyviridae. The possible occurrence of recombination between the isolates and the movement of the virus in the cardamom tract of south India are discussed.

Expression of Cardamom mosaic virus coat protein in Escherichia coli and its assembly into filamentous aggregates

Cardamom mosaic virus (CdMV), a member of the genus Macluravirus of Potyviridae, causes a mosaic disease in cardamom. A polyclonal antiserum was raised against the purified virus and IgG was prepared. Electron microscopic studies on the purified virus showed flexuous filamentous particles of approximately 800 nm in length, typical of members of Potyviridae. The coat protein (CP) encoding sequence of the virus was expressed in Escherichia coli and the protein purified by affinity chromatography under denaturing conditions. The viral nature of the expressed CP was confirmed by positive reaction with anti CdMV IgG in a Western blot. The expressed CP aggregated irreversibly upon renaturation at concentrations above 0.07 mg/ml. The expression of the CP led to the formation of filamentous aggregates in E. coli as observed by immuno-gold electron microscopy. The filamentous aggregates were of 100-150 nm in length. Immuno-capture RT-PCR confirmed the absence of coat protein mRNA in the filamentous aggregates. Deletion mutations, which were expected to inhibit virus assembly, were introduced in the core region of the coat protein. However, these mutations did not improve the solubility of the CP in non-denaturing buffers.

3'-Terminal sequence analysis of the RNA genome of the Indian isolate of cardamom mosaic virus: a new member of genus Macluravirus of potyviridae

Cardamom mosaic virus, a possible member of the family Potyviridae has been associated with the mosaic disease (Katte disease) of small cardamom in India. A virus isolated from the symptomatic cardamom leaves was positive in ELISA only with antiserum to the Guatemalan isolate of cardamom mosaic virus and not with a number of other potyviruses. The size of the viral RNA (8.5 kb) and the molecular weight of the coat protein (CP) (38 kDa) were determined. A 1.8-kb product containing the partial nuclear inclusion body (NIb) gene, the entire coat protein gene and the 3' untranslated region (UTR) was amplified by reverse transcription (RT) and polymerase chain reaction (PCR), cloned and sequenced. The viral origin of the clone was confirmed by Northern hybridization with viral RNA. The experimentally determined N-terminal sequence of the CP matched with the deduced amino acid sequence of the CP gene. Sequence analysis of the clone suggests that the cardamom mosaic virus is a member of the Maclurvirus genus of the family Potyviridae.

Molecular modelling of epitope presentation using membrane protein OmpC

Three-dimensional models of the chimeric S. typhi OmpC protein carrying an epitope from rotavirus VP4 capsid protein on either of two exposed loops (fourth and sixth) were constructed separately, using computer-aided homology modelling. The theoretical model of S. typhi OmpC was used as a template. The monomers were initially energy minimized. The trimers were generated for both the chimeric S. typhi OmpC proteins and the structures were optimized after several cycles of minimization. The surface accessibility calculations for the resulting models show that epitope recognition should be more effective in the fourth loop than in the sixth loop, in accordance with the experimental results on the immunogenic nature of the rotaviral epitope inserted into the two putative loops of S. typhi OmpC.

Empty sella syndrome presenting as galactorrhoea

A prolactin secreting tumour is the commonest cause of the amenorrhoea-galactorrhoea syndrome. Galactorrhoea is a rare presentation of an empty sella syndrome. The empty sella syndrome commonly presents with headache and visual impairment and occasionally with endocrine disturbances in hypertensive middle aged women. The authors present a case of hyperprolactinemia resulting in galactorrhoea in a middle aged lady associated with a primary empty sella syndrome.

Region-specific attenuation of a trypsin-like protease in substantia nigra following dopaminergic neurotoxicity by 1-methyl-4-phenyl-1,2, 3,6-tetrahydropyridine

We analysed apoptosis, caspase-1 and -3, and trypsin-like protease activity in the nigrostriatal pathway during 1-methyl-4-phenyl-1,2,3, 6-tetrahydropyridine (MPTP)-induced neurotoxicity. MPTP injected (30 mg/kg, i.p., twice, 16 h apart) mice were sacrificed on 1, 2 and 7 days. DNA extracted from nucleus caudatus putamen (NCP) and substantia nigra (SN) was subjected to agarose gel electrophoresis. Typical apoptotic-like DNA cleavage was absent in SN or NCP after this dose of MPTP. A trypsin-like protease activity was significantly decreased in SN and not in NCP. While caspase-3 activity in the whole brain was increased significantly, caspase-1 activity was unaffected. Striatal dopamine content was decreased to 75% by 7 days. The absence of typical DNA 'ladder' when there was severe striatal dopamine depletion suggests that in vivo MPTP-mediated dopaminergic neurotoxicity may not involve apoptotic cell death, and explains why in mice MPTP-induced dopamine depletion is transient. The region-specific decrease in trypsin-like protease activity and absence of caspase-3 activation in SN signify the importance of trypsin-like protease in the regulation of apoptosis in MPTP-neurotoxicity in mice.