25 research outputs found
SYNTHESIS OF NOVEL CHALCONES OF SCHIFF'S BASES AND TO STUDY THEIR EFFECT ON BOVINE SERUM ALBUMIN
Objective: Some novel chalcones consisting –unsaturated carbonyl group and C=N bond were synthesized i.e. 1-(4-(benzylideneamino)phenyl)-3-phenylprop-2-en-1-ones and studied the influence of their presence on bovine serum albumin.Methods: 1-(4-(benzylideneamino)phenyl)-3-phenylprop-2-en-1-ones were synthesized by the reaction of substituted benzaldehydes with 1-((4-benzylideneamino)phenyl)ethanone and in the presence of a base. The structures were confirmed by their IR and 1HNMR spectra. After establishing the structures of 1-(4-(benzylideneamino)phenyl)-3-phenylprop-2-en-1-ones, their effect were observed on BSA in solution.Results: Out of synthesized chalcones, 1-(4-(4-(3-phenylallylideneamino)phenyl)-3-p-tolylprop-2-en-1-one is most reactive chalcone as it decreased the availability of BSA in solution to maximum extent.Conclusion: 1-(4-(benzylideneamino)phenyl)-3-phenylprop-2-en-1-ones interact with the bovine serum albumin which is responsible for the transportation of a number of compounds.Keywords: Bovine serum albumin, interaction studies, chalcones
Symbiotic nitrogen fixation in legume nodules: process and signaling. A review
The Green Revolution was accompanied by a huge increase in the
application of fertilizers, particularly nitrogen. Recent studies indicate
that a sizeable proportion of the human population depends on synthetic
nitrogen (N) fertilizers to provide the 53 million t N that is harvested
globally in food crops each year. Nitrogen fertilizers affect the balance of
the global nitrogen cycle, pollute groundwater and increase atmospheric
nitrous oxide (NO), a potent "greenhouse" gas. The production of
nitrogen fertilizer by industrial nitrogen fixation not only depletes our
finite reserves of fossil fuels, but also generates large quantities of
carbon dioxide, contributing to global warming. The process of biological
nitrogen fixation offers an economically attractive and ecologically sound
means of reducing external nitrogen input and improving the quality and
quantity of internal resources. Recent studies show that in irrigated
cropping systems, legume N is generally less susceptible to loss processes
than fertilizers. Biological nitrogen fixation (BNF) has provided a number of useful
paradigms for both basic and applied research. Establishing a fully
functional symbiosis requires a successful completion of numerous steps that
lead from recognition signals exchanged between the plant and bacteria to
the differentiation and operation of root nodules, the plant organ in which
nitrogen fixation takes place. The initial sensing of the two organisms by
each other starts with the release of root exudates by the plant that
include flavonoids and nutrients such as organic acids and amino acids.
Flavonoids secreted by the host plant into the rhizosphere function as
inducers of the rhizobial nod genes. nod gene induction results in the secretion of
lipochitin oligosaccharides that are thought to bind to specific plant
receptor kinases that contain LysM motifs, such as NFR1 and NFR5 in Lotus japonicus and LYK3
and LTK4 in Medicago truncatula. This initiates a complex signaling pathway involving calcium
spiking in root hairs. The result is that the root hairs curl and trap the
rhizobia, which then enter the root hair through tubular structures known as
infection threads that are formed by the plant. The infection threads then
grow into the developed nodule tissue. Ultimately, the invading bacteria are
taken into the plant cell by a type of endocytosis in which they are
surrounded by a plant-derived peribacteroid membrane (PBM). The resulting
symbiosomes fill the plant cell cytoplasm and as plant and bacterial
metabolism develops, the bacteria become mature bacteroids able to convert
atmospheric nitrogen to ammonium. To increase knowledge of this
system of particular importance in sustainable agriculture, major emphasis
should be laid on the basic research. More work is needed on the genes
responsible in rhizobia and legumes, the structural chemical bases of
rhizobia/legume communication, and signal transduction pathways responsible
for the finely orchestrated induction of the symbiosis-specific genes
involved in nodule development and nitrogen fixation. This review unfolds
the various events involved in the progression of symbiosis
Arbuscular mycorrhizal networks: process and functions. A review
An unprecedented, rapid change in environmental conditions is being observed, which
invariably overrules the adaptive capacity of land plants. These environmental changes
mainly originate from anthropogenic activities, which have aggravated air and soil
pollution, acid precipitation, soil degradation, salinity, contamination of natural and
agro-ecosystems with heavy metals such as cadmium (Cd), lead (Pb), mercury (Hg), arsenic
(As), global climate change, etc. The restoration of degraded natural habitats using
sustainable, low-input cropping systems with the aim of maximizing yields of crop plants
is the need of the hour. Thus, incorporation of the natural roles of beneficial
microorganisms in maintaining soil fertility and plant productivity is gaining importance
and may be an important approach. Symbiotic association of the majority of crop plants
with arbuscular mycorrhizal (AM) fungi plays a central role in many microbiological and
ecological processes. In mycorrhizal associations, the fungal partner assists its plant
host in phosphorus (P) and nitrogen (N) uptake and also some of the relatively immobile
trace elements such as zinc (Zn), copper (Cu) and iron (Fe). AM fungi also benefit plants
by increasing water uptake, plant resistance and biocontrol of phytopathogens, adaptation
to a variety of environmental stresses such as drought, heat, salinity, heavy metal
contamination, production of growth hormones and certain enzymes, and even in the uptake
of radioactive elements. The establishment of symbiotic association usually involves
mutual recognition and a high degree of coordination at the morphological and
physiological level, which requires a continuous cellular and molecular dialogue between
both the partners. This has led to the identification of the genes, signal transduction
pathways and the chemical structures of components relevant to symbiosis; however,
scientific knowledge on the physiology and function of these fungi is still limited. This
review unfolds our current knowledge on signals and mechanisms in the development of AM
symbiosis; the molecular basis of nutrient exchange between AM fungi and host plants; and
the role of AM fungi in water uptake, disease protection, alleviation of various abiotic
soil stresses and increasing grain production
Nitrogen fixation and carbon metabolism in legume nodules
138-142A large amount of energy is utilized by
legume nodules for the fixation of nitrogen and assimilation of fixed nitrogen (ammonia)
into organic compounds. The source of energy is provided in the form of photosynthates
by the host plant. Phosphoenol pyruvate carboxylase (PEPC) enzyme, which is responsible
for carbon dioxide fixation in C4 and crassulacean
acid metabolism plants, has also been
found to play an important role in carbon metabolism in legume root nodule. PEPC
mediated CO2 fixation in nodules results
in the synthesis of C4 dicarboxylic acids, viz. aspartate, malate, fumarate
etc. which can be transported into bacteroids with the intervention of
dicarboxylate transporter (OCT) protein. PEPC has been purified from the root nodules
of few legume species. Information on the relationship between nitrogen fixation
and carbon metabolism through PEPC in leguminous plants is scanty and
incoherent. This review summarizes the various aspects of carbon and nitrogen
metabolism in legume root nodules
Zinc-Arbuscular Mycorrhizal Interactions: Effect on Nutrient Pool, Enzymatic Antioxidants, and Osmolyte Synthesis in Pigeonpea Nodules Subjected to Cd Stress
<p>The intent of the experiments was to analyze impact of cadmium (Cd) and/or zinc (Zn) on membrane functionality, nutrient acquisition, antioxidant defense, and osmolyte accumulation in nodules of two pigeonpea (<i>Cajanus cajan</i> (L.) Millsp.) genotypes (Sel 85N and P792) with and without arbuscular mycorrhizal (AM) fungus <i>Funneliformis mosseae</i>. Findings demonstrated that accumulation of Cd and Zn in nodules resulted in membrane destabilization, nutrient imbalance, increased antioxidant enzyme activities [superoxide dismutase (SOD), catalase (CAT), peroxidase (POX), and glutathione reductase (GR)], and osmoprotectants such as total free amino acids (FAA), total soluble sugars (TSS), proline, and glycine betaine (GB). Cd had higher negative effects than Zn. P792 was comparatively more metal sensitive and displayed higher reductions than Sel 85N. Application of Zn decreased Cd uptake and reduced the phytotoxic effects of Cd. Zn<sub>1000</sub> in combination with <i>F. mosseae</i> restored nodular membrane stability; enhanced nutrient pool [phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), and iron (Fe)]; and boosted antioxidant enzyme activities and osmolyte synthesis in a genotype-dependent manner.</p
Brainstem involvement in subacute sclerosing panencephalitis
The parieto-occipital region of the brain is most frequently and
severely affected in subacute sclerosing panencephalitis (SSPE). The
basal ganglia, cerebellum and corpus callosum are less commonly
involved. Brainstem involvement is rarely described in SSPE, and
usually there is involvement of other regions of the brain. We describe
a patient with subacute sclerosing panencephalitis with brain magnetic
resonance imaging showing extensive brainstem involvement without
significant involvement of other cortical structures. Though rarely
described in SSPE, one should be aware of such brainstem and cerebellum
involvement, and SSPE should be kept in mind when brainstem signal
changes are seen in brain MRI with or without involvement of other
regions of brain to avoid erroneous reporting
An unusual case of Takayasu's arteritis: Evaluation by CT angiography
Takayasu's arteritis is a chronic, idiopathic, medium and large vessel vasculitis involving aorta and its main branches. Frequent neurological manifestations include postural syncope, seizures, and blindness. Stroke, as presenting feature of Takayasu's arteritis, is unusual. CT angiography reveals characteristic involvement of aortic arch and its branches. Involvement of intracranial vasculature is rather unusual. We are describing an unusual patient of Takayasu's arteritis who presented with recurrent disabling syncopal attacks and had extensive involvement of intracranial vasculature. CT angiography revealed severe involvement of aortic arch. There was near complete occlusion at origins of both subclavian arteries, distal flow was maintained by collateral vessels along the chest wall. There was near total occlusion (at origin) of right common carotid with normal flow in distal part. The left common carotid was more severely involved showing greater than 80% narrowing in proximal half of the vessel. CT angiography also revealed involvement of left internal carotid artery, narrowing of left middle cerebral artery and involvement of cortical vessels. Patient was treated with oral corticosteroids. She improved remarkably after two and half months of follow up