Mohd Adnan

Analysis of rpoS and bolA gene expression under various stress-induced environments in planktonic and biofilm phase using 2−ΔΔCT method

Genetic adaptation is one of the key features of Escherichia coli (E. coli) that ensure its survival in different hostile environments. E. coli seems to initiate biofilm development in response to specific environmental cues. A number of properties inherent within bacterial biofilms indicate that their gene expression is different from that of planktonic bacteria. Two of the possible important genes are rpoS and bolA. The rpoS gene has been known as the alternative sigma (σ) factor, which controls the expression of a large number of genes, which are involved in responses to a varied number of stresses, as well as transition to stationary phase from exponential form of growth. Morphogene bolA response to stress environment leads to round morphology of E. coli cells, but little is known about its involvement in biofilms and its development or maintenance. The purpose of this study was to understand and analyse the responses of rpoS and bolA gene to sudden change in the environment. In this study, E. coli K-12 MG1655, rpoS, and bolA mutant strains were used and gene expression was studied. Results show that both genes contribute to the ability to respond and adapt in response to various types of stresses. RpoS response to various stress environments was somehow constant in both the planktonic and biofilm phases, whereas bolA responded well under various stress conditions, in both planktonic and biofilm mode, up to 5–6-fold change in the expression was noticed in the case of pH variation and hydrogen peroxide stress (H2O2) as compared with rpoS.

Implication of Caspase-3 as a Common Therapeutic Target for Multineurodegenerative Disorders and Its Inhibition Using Nonpeptidyl Natural Compounds

Caspase-3 has been identified as a key mediator of neuronal apoptosis. The present study identifies caspase-3 as a common player involved in the regulation of multineurodegenerative disorders, namely, Alzheimers disease (AD), Parkinsons disease (PD), Huntingtons disease (HD), and amyotrophic lateral sclerosis (ALS). The protein interaction network prepared using STRING database provides a strong evidence of caspase-3 interactions with the metabolic cascade of the said multineurodegenerative disorders, thus characterizing it as a potential therapeutic target for multiple neurodegenerative disorders. In silico molecular docking of selected nonpeptidyl natural compounds against caspase-3 exposed potent leads against this common therapeutic target. Rosmarinic acid and curcumin proved to be the most promising ligands (leads) mimicking the inhibitory action of peptidyl inhibitors with the highest Gold fitness scores 57.38 and 53.51, respectively. These results were in close agreement with the fitness score predicted using X-score, a consensus based scoring function to calculate the binding affinity. Nonpeptidyl inhibitors of caspase-3 identified in the present study expeditiously mimic the inhibitory action of the previously identified peptidyl inhibitors. Since, nonpeptidyl inhibitors are preferred drug candidates, hence, discovery of natural compounds as nonpeptidyl inhibitors is a significant transition towards feasible drug development for neurodegenerative disorders.

A modified Lumry-Eyring analysis for the determination of the predominant mechanism underlying the diminution of protein aggregation by glycerol.

Aggregation of aspartate-β-semialdehyde dehydrogenase (ASD) was analyzed by applying modified Lumry–Eyring with nucleated polymerization (LENP) model. Intrinsic nucleation time scales were determined. In absence of glycerol, ASD undergoes concentration and time-dependent polymerization into low-molecular weight soluble aggregates and thereafter condensation into insoluble aggregates. In the presence of increasing solvent glycerol concentration, the aggregation becomes more and more nucleation dominated, with slower polymerization to low-molecular weights soluble aggregates, without any condensation into insoluble aggregates. Effective nucleus size as well as the number of monomers in each irreversible growth event were sensitive to the changes in solvent glycerol concentration. Glycerol-directed diminution of aggregation appears to be largely due to the inhibition of rearrangement (decreased nucleation rearrangement rate coefficient, Kr,x) because of compaction induced due to preferential hydration, thus, preventing the soluble aggregates from locking into irreversible soluble nuclei. Appreciably decreased Kr,x (as compared to nucleation dissociation constant, Kd,x), appears to be responsible for increased nucleus size at higher solvent glycerol concentration. This study explains how modified LENP model can be applied to determine the predominant mechanism responsible for the diminution of aggregation by polyhydric alcohols (glycerol).

Functional and health promoting inherent attributes of Enterococcus hirae F2 as a novel probiotic isolated from the digestive tract of the freshwater fish Catla catla

Background Probiotic microorganisms are gaining global importance because of their use in the preparation of a nutraceutical or in the treatment of infections. As per the health industry demand, there is an urgent need for exploring new indigenous probiotic strains with its specific origin due to variation in gut microflora, different food habits and specific host-microbial interactions. The main objective of the present study was to isolate and identify a novel probiotic Enterococcus strain from the gut of Catla catla fish and evaluate its potentiality as a potent probiotic. Methods The whole study was designed with the isolation of novel lactic acid bacterial strain from the gut of Catla catla fish with their biochemical and molecular identifications. The potentiality of the isolated strain as a potent probiotic was carried out according to the parameters described in FAD/WHO guidelines for the evaluation of probiotics in food. Results The isolated strain was confirmed as Enterococcus hirae F2 on the basis of various biochemical and 16s rRNA gene sequencing methods. Enterococcus hirae F2 was able to survive under highly acidic and bile salt concentration with the ability for the production of lipase and Bsh enzyme. It was also able to survive under simulated gastrointestinal conditions with the inhibition ability of various pathogens. The antioxidant potentiality with the cell surface hydrophobicity and cell aggregation ability confirms its potentiality as a potent probiotic. All the results detail the potency of Enterococcus hirae F2 as a novel probiotic for a safer use. Discussion The isolation of Enterococcus hirae with probiotic potential from the gut of fish is a new approach and done for the first time. However, the whole study concluded that the isolated strain might be used as a novel probiotic in the food industry for the production of new probiotic products which imparts health benefits to the host.

Optimization of Extraction Parameters for Enhanced Production of Ovotransferrin from Egg White for Antimicrobial Applications

Ovotransferrin is the second most abundant protein (~12-13% of the total egg protein) in egg white after ovalbumin. Ovotransferrin is a potent natural antimicrobial agent as it possesses antibacterial, antifungal, and antiviral properties and is also the major metal binding protein found in egg, which makes it an industrially important protein. Ovotransferrin was extracted from egg white using its metal (iron) binding properties. In the present study, eggs from two different sources were used (fresh local eggs from domestic household source and poultry eggs from shops) to compare the results and Response Surface Methodology was used for the experiment design and data analysis. The following extraction conditions were optimized so as to maximize the yield of ovotransferrin from egg white: ethanol % (v/v) and pH and volume (mL) of 25 mM FeCl3/50 mL of egg white. A maximum yield of ~85 ± 2.5% was obtained near the optimum extraction conditions. The yield was calculated based on the theoretical value (934 mg) of ovotransferrin in 100 mL of 1.5x diluted egg white solution. Our results suggest that efficient downstream processing may reduce the cost of overall production process of this promising enzyme, making it a natural and cost-effective alternative to the existing chemically synthesized antimicrobial agents.

Formulation, evaluation and bioactive potential of Xylaria primorskensis terpenoid nanoparticles from its major compound xylaranic acid

In recent years, fungi have been shown to produce a plethora of new bioactive secondary metabolites of interest, as new lead structures for medicinal and other pharmacological applications. The present investigation was carried out to study the pharmacological properties of a potent and major bioactive compound: xylaranic acid, which was obtained from Xylaria primorskensis (X. primorskensis) terpenoids in terms of antibacterial activity, antioxidant potential against DPPH & H2O2 radicals and anticancer activity against human lung cancer cells. Due to terpenoid nature, low water solubility and wretched bioavailability, its pharmacological use is limited. To overcome these drawbacks, a novel xylaranic acid silver nanoparticle system (AgNPs) is developed. In addition to improving its solubility and bioavailability, other advantageous pharmacological properties has been evaluated. Furthermore, enhanced anticancer activity of xylaranic acid and its AgNPs due to induced apoptosis were also confirmed by determining the expression levels of apoptosis regulatory genes p53, bcl-2 and caspase-3 via qRT PCR method. This is the first study developing the novel xylaranic acid silver nanoparticle system and enlightening its therapeutic significance with its improved physico-chemical properties and augmented bioactive potential.

Effect of pH, temperature and incubation time on cordycepin production from Cordyceps militaris using solid-state fermentation on various substrates

ABSTRACT Cordyceps militaris has been a keystone in combating myriad health problems with innumerable far-reaching therapeutic effects. The present study focuses on effect of fermentation conditions such as (pH, temperature and incubation time) and solid-state fermentation (SSF) using solid substrates (wheat, oat and rice) on production of cordycepin. Temperature, pH and incubation time was found to have a direct effect on cordycepin production. The best possible combination of temperature, pH and incubation time was found to be 25°C, 5.5 and 21 days, respectively, for maximum cordycepin production. SSF of solid substrate medium culture leads to the production of cordycepin. Among the solid substrates, rice medium had highest cordycepin production (814.60 mg/g) followed by oat and wheat medium (638.85 and 565.20 mg/g, respectively). This method provides an effective way for increasing the cordycepin production at a large scale. This study could have a wide application in other fermentation processes at industrial level.

Significance and potential of marine microbial natural bioactive compounds against biofilms/biofouling: necessity for green chemistry

Natural products from the unique environments of sea water and oceans represent a largely unfamiliar source for isolation of new microbes, which are potent producers of secondary bioactive metabolites. These unique life-forms from the marine ecosphere have served as an important source of drugs since ancient times and still offer a valuable resource for novel findings by providing remedial treatments. Therefore, it can be expected that many naturally bioactive marine microbial compounds with novel structures and bioactivities against those from terrestrial environments may be found among marine metabolites. Biofilms in aquatic environment possess serious problems to naval forces and oceanic industries around the globe. Current anti-biofilm or anti-biofouling technology is based on the use of toxic substances that can be harmful to their surrounding natural locales. Comprehensive research has been done to examine the bioactive potential of marine microbes. Results are remarkably varied and dynamic, but there is an urgent need for bioactive compounds with environmentally friendly or “green” chemical activities. Marine microbes have the potential as upcoming and promising source of non-toxic compounds with sustainable anti-biofouling/anti-biofilm properties as they can produce substances that can inhibit not only the chemical components required for biofilm production but also the attachment, microorganism growth, and/or cell–cell communication.

Physiological and Molecular Characterization of Biosurfactant Producing Endophytic Fungi Xylaria regalis from the Cones of Thuja plicata as a Potent Plant Growth Promoter with Its Potential Application

Currently, there is an absolute concern for all nations in agricultural productivity to meet growing demands of human population. In recent time, biosurfactants produced by diverse group of microorganisms are used to achieve such demands as it is known for its ecofriendly use in elimination of plant pathogens and for increasing the bioavailability of nutrients for plants. Endophytic fungi are the important source of secondary metabolites and novel bioactive compounds for different biological applications. In the present study, endophytic fungi Xylaria regalis (X. regalis) recovered from the cones of Thuja plicata was evaluated for its biosurfactant producing ability and plant growth-promoting abilities through various screening methods and also via its antagonistic activity against phytopathogens like Fusarium oxysporum and Aspergillus niger. In addition, X. regalis was also tested in vivo for a various range of growth parameters in chilli under greenhouse conditions. Significant increase in shoot and root length, dry matter production of shoot and root, chlorophyll, nitrogen, and phosphorus contents of chilli seedlings was found, which reveals its ability to improve the growth of crop plants. Hence, this study suggests the possibility of biosurfactant producing endophytic fungi X. regalis as a source of novel green biosurfactant for sustainable agriculture to achieve growing demands.

In pursuit of cancer metastasis therapy by bacteria and its biofilms: History or future

The 20th century observation of increasing comprehensive load of cancer, advanced cancer prevention strategies, creative hypotheses and control procedures by research communities are being traversed and stimulated in multiple facets. Inference of genetically modified non-pathogenic and natural bacterial species as potential anti-tumor agents is one such original perspective. Live, genetically modified non-pathogenic or attenuated bacterial species are able to form biofilms by multiplying selectively or non-selectively on cancer cells, which will lead to metastasis disruption. However, the appearance of gene-directed prodrug therapy and recombinant DNA technology has invigorated the notice in range of applications employing bacteria and bacterial therapy and have been carried out. The most possible and promising upcoming strategies are bacteria mediated cancer treatment. Significant efficacy in pre-clinical studies have been demonstrated and some are presently under clinical investigation. The theorem is that cancer metastasis can either be blunt by opponent bacterial biofilm infection or serve as model vectors for delivering therapeutic proteins to tumors or generation of the new phenotypes during the SOS reaction incite by anticancer drugs.