The changing paradigm of rhizobial taxonomy and its systematic growth upto postgenomic technologies.

Rhizobia are a diazotrophic group of bacteria that are usually isolated form the nodules in roots, stem of leguminous plants and are able to form nodules in the host plant owing to the presence of symbiotic genes. The rhizobial community is highly diverse, and therefore, the taxonomy and genera-wise classification of rhizobia has been constantly changing since the last three decades. This is mainly due to technical advancements, and shifts in definitions, resulting in a changing paradigm of rhizobia taxonomy.

Rhizodegradation of Pyrene by a Non-pathogenic Isolate Applied With L. and Changes in the Rhizobacterial Community.

The non-clinical variants, isolated from different environments, are now well acknowledged for their role in plant-growth promotion and biodegradation of pollutants. In the present study, a non-clinical environmental isolate AWD5 is being described for rhizoremediation of pyrene, applied through the rhizosphere of an ornamental plant, L (marigold). The non-pathogenic nature of AWD5 was established using an mouse model experiment, where AWD5 was unable to cause lung infection in tested mice.

The Endophytic Microbiome as a Hotspot of Synergistic Interactions, with Prospects of Plant Growth Promotion.

The plant root is the primary site of interaction between plants and associated microorganisms and constitutes the main components of plant microbiomes that impact crop production. The endophytic bacteria in the root zone have an important role in plant growth promotion. Diverse microbial communities inhabit plant root tissues, and they directly or indirectly promote plant growth by inhibiting the growth of plant pathogens, producing various secondary metabolites.

Enrichment of antibiotic resistance genes (ARGs) in polyaromatic hydrocarbon-contaminated soils: a major challenge for environmental health.

Polyaromatic hydrocarbons (PAHs) are widely spread ecological contaminants. Antibiotic resistance genes (ARGs) are present with mobile genetic elements (MGE) in the bacteria. There are molecular evidences that PAHs may induce the development of ARGs in contaminated soils.

Development, spread and persistence of antibiotic resistance genes (ARGs) in the soil microbiomes through co-selection.

Bacterial pathogens resistant to multiple antibiotics are emergent threat to the public health which may evolve in the environment due to the co-selection of antibiotic resistance, driven by poly aromatic hydrocarbons (PAHs) and/or heavy metal contaminations. The co-selection of antibiotic resistance (AMR) evolves through the co-resistance or cross-resistance, or co-regulatory mechanisms, present in bacteria. The persistent toxic contaminants impose widespread pressure in both clinical and environmental setting, and may potentially cause the maintenance and spread of antibiotic resistance genes (ARGs).

Distinctive features gleaned from the comparative genomes analysis of clinical and non-clinical isolates of Klebsiella pneumoniae.

It is of interest to describe the distinctive features gleaned from the comparative genome analysis of clinical and non-clinical isolates of Klebsiella pneumoniae. The core genome of K. pneumoinae consisted of 3568 genes.

Synthesis of titanium oxide nanoparticles using Aloe barbadensis mill and evaluation of its antibiofilm potential against Pseudomonas aeruginosa PAO1.

Titanium dioxide nanoparticles (TiO-NPs) were synthesized using the aqueous leaf extract of Aloe barbadensis as a reducing and fabricating agent. The biosynthesis of the TiO-NPs was initially confirmed by UV-vis spectroscopy. Based on the HRTEM and FESEM analysis, the biosynthesized NPs were found to be polydispersed and predominantly spherical in shape, with an average size of ~20 nm.

Anti-quorum sensing and anti-biofilm activity of 5-hydroxymethylfurfural against Pseudomonas aeruginosa PAO1: Insights from in vitro, in vivo and in silico studies.

Pseudomonas aeruginosa is one of the most common pathogens associated with nosocomial infections and a great concern to immunocompromised individuals especially in the cases of cystic fibrosis, AIDS and burn wounds. The pathogenicity of P. aeruginosa is largely directed by the quorum sensing (QS) system.

Evaluation of in vivo antioxidant potential of (L.) Alston and Roxb. towards oxidative stress response in .

Excessive production and restricted elimination of free radicals like superoxide, hydroxyl radical (OH), anion radical (O ), and non-radical hydrogen peroxide (HO) are related to the development of cancer, arteriosclerosis, arthritis and neurodegenerative diseases. According to a report of World Health Organisation, about 80% of the population living in the developing countries predominantly depends on the traditional medicine for their primary healthcare. Plants possess innate ability to synthesize a wide variety of enzymatic and non-enzymatic antioxidants capable of attenuating ROS-induced oxidative damage.

Cinnamic acid attenuates quorum sensing associated virulence factors and biofilm formation in Pseudomonas aeruginosa PAO1.

Objective: Anti-quorum sensing and anti-biofilm efficacy of Cinnamic acid against Pseudomonas aeruginosa was comparatively assessed with respect to potent quorum sensing inhibitor, Baicalein.

Results: At sub-lethal concentration, Cinnamic acid effectively inhibited both the production of the QS-dependent virulence factors and biofilm formation in P. aeruginosa without affecting the viability of the bacterium.

The rhizosphere microbiome: Significance in rhizoremediation of polyaromatic hydrocarbon contaminated soil.

Microbial communities are an essential part of plant rhizosphere and participate in the functioning of plants, including rhizoremediation of petroleum contaminants. Rhizoremediation is a promising technology for removal of polyaromatic hydrocarbons based on interactions between plants and microbiome in the rhizosphere. Root exudation in the rhizosphere provides better nutrient uptake for rhizosphere microbiome, and therefore it is considered to be one of the major factors of microbial community function in the rhizosphere that plays a key role in the enhanced PAH biodegradation.

Attenuation of quorum sensing controlled virulence factors and biofilm formation in Pseudomonas aeruginosa by pentacyclic triterpenes, betulin and betulinic acid.

The production of virulence determinants and biofilm formation in numerous pathogens is regulated by the cell-density-dependent phenomenon, Quorum sensing (QS). The QS system in multidrug resistant opportunistic pathogen, P. aeruginosa constitutes of three main regulatory circuits namely Las, Rhl, and Pqs which are closely linked to its pathogenicity and establishment of chronic infections.

Genomic insights of aromatic hydrocarbon degrading AWD5 with plant growth promoting attributes: a paradigm of soil isolate with elements of biodegradation.

This research employs draft genome sequence data of AWD5 to explore genes that contribute to the degradation of polyaromatic hydrocarbon (PAH) and stimulate plant growth, for rhizosphere-mediated bioremediation. Annotation analysis suggests that the strain AWD5 not only possess gene clusters for PAH utilization, but also for utilization of benzoate, fluorobenzoate, phenylacetate (), hydroxyphenylacetic acid (), 3-hydroxyphenyl propionate (). A comparative genome analysis revealed that the genome of AWD5 was highly similar with genomes of environmental as well as clinical isolates.

Shape dependent physical mutilation and lethal effects of silver nanoparticles on bacteria.

In this report, spherical silver nanoparticle (AgNP-sp) and rod-shaped silver nanoparticle (AgNR) were prepared by chemical reduction method and their antibacterial activity against various Gram-positive and Gram-negative bacteria had been evaluated for their efficiency. Minimal inhibitory concentration (MIC) tests were conducted to study the antibacterial properties, and substantiated with killing kinetics of silver nanoparticles (AgNPs). The study revealed that both AgNP-sp and AgNRs are good antibacterial candidates.

Green synthesis of anisotropic gold nanoparticles using hordenine and their antibiofilm efficacy against .

is a notorious pathogen that causes biofilm aided infections in patients with cystic fibrosis and burn wounds, resulting in significant mortality in immunocompromised individuals. This study reports a novel one-step biosynthesis of gold nanoparticles using phytocompound, hordenine (HD), as a reducing and capping agent. The synthesis of the anisotropic hordenine-fabricated gold nanoparticles (HD-AuNPs) with an average particle size of 136.

Facile green synthesis of baicalein fabricated gold nanoparticles and their antibiofilm activity against Pseudomonas aeruginosa PAO1.

Biofilm formation is one of the major problems associated with chronic diseases and also attributes for the antibiotic resistance in bacteria. In recent times nanoparticles have been utilized to improve the efficacy of the existing antimicrobial and anti-biofilm agents. The ease in functionalization of gold nanoparticles (AuNPs) makes them a potential carrier for antimicrobial agents.

Green Synthesized Nanomaterials as Theranostic Platforms for Cancer Treatment: Principles, Challenges and the Road Ahead.

With the emergence of nanotechnology, new methods have been developed for engineering various nanoparticles for biomedical applications. Nanotheranostics is a burgeoning research field with tremendous prospects for the improvement of diagnosis and treatment of various cancers. However, the development of biocompatible and efficient drug/gene delivery theranostic systems still remains a challenge.

Draft Genome Sequence of Klebsiella pneumoniae AWD5.

Here, we report the draft genome sequence of Klebsiella pneumoniae strain AWD5, isolated from an automobile workshop in India. The de novo assembly resulted in a 4,807,409 bp genome containing 25 rRNA genes, 81 tRNAs, and 4,636 coding sequences (CDS). It carries important genes for polyaromatic hydrocarbon degradation and benzoate degradation.

Ecofriendly biosorption of dyes and metals by bacterial biomass of Aeromonas hydrophila RC1.

The ability of dried bacterial biomass in azo dye and heavy metal removal from aqueous solution was explored. Biosorption of three textile dyes, Eriochrome black T (EBT), Acid Red 26 (AR) and Trypan blue (TB) and heavy metals (Pb and Cr) by dried biomass of Aeromonas hydrophila RC1, was investigated in a batch system under various parameters such as dye concentration, contact time, concentration of biomass, pH, and temperature. The experimental results showed that the extent of biosorption for dyes increased with increase in initial concentration of dyes, biomass concentration, contact time, temperature and decreased with increase in pH.

Green rapid biogenic synthesis of bioactive silver nanoparticles (AgNPs) using Pseudomonas aeruginosa.

The present work was focused on isolating a bacterial strain of Pseudomonas sp. with the ability to synthesise AgNPs rapidly. A strain of Pseudomonas aeruginosa designated JO was found to be a potential candidate for rapid synthesis of AgNPs with a synthesis time of 4h in light, at room temperature which is a shorter time period noticed for the synthesis when compared to the previous reports Biosynthesis of AgNPs was achieved by addition of culture supernatant with aqueous silver nitrate solution (1 mM).