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Chromobacterium is a rod-shaped, Gram-negative, facultatively anaerobic bacteria with a cosmopolitan distribution. Just about 160 Chromobacterium violaceum incidents have been reported globally, but then once infected, it has the ability to cause deadly septicemia, and infections in the lungs, liver, brain, spleen, and lymphatic systems that might lead to death. C. violaceum produces and utilizes violacein to kill bacteria that compete with it in an ecological niche. Violacein is a hydrophobic bisindole that is delivered through an efficient transport route termed outer membrane vesicles (OMVs) through the aqueous environment. OMVs are small, spherical segments detached from the outer membrane of Gram-negative bacteria. C. violaceum OMV secretions are controlled by a mechanism called the quorum sensing system CviI/CviR, which enables cell-to-cell communication between them and regulation of various virulence factors such as biofilm formation, and violacein biosynthesis. Another virulence factor bacterial type 3 secretion system (T3SS) is divided into two types: Cpi-1 and Cpi-2. Cpi-1’s needle and rod effector proteins are perhaps recognized by NAIP receptors in humans and mice, activating the NLRC4 inflammasome cascade, effectively clearing spleen infections via pyroptosis, and cytotoxicity mediated by IL-18-driven Natural killer (NK) cells in the liver. In this paper, we attempt to interrelate quorum-controlled biofilm formation, violacein production, violacein delivery by OMVs and T3SS effector protein production and host mediated immunological effects against the Cpi1 of T3SS. We suggest a research path with natural bioactive molecule like palmitic acid that can act as an anti-quorum agent by reducing the expression of virulence factors as well as an immunomodulatory agent that can augment innate immune defense by hyperactivation of NLRC4 inflammasome hence dramatically purge C. violaceum infections.

Chromobacterium violaceum is a pathogenic bacterium that can infect humans and animals, yet the role of its outer membrane vesicles (OMVs) in mediating pathogenicity remains underexplored. This study evaluated the effects of linoleic acid (LA) and stearic acid (SA) on quorum sensing (QS)-mediated violacein production, biofilm formation, and OMV biogenesis in C. violaceum. Our findings revealed that 2 mM LA and 1 mM SA effectively quench QS, leading to a significant reduction in violacein production, biofilm formation, and OMV biogenesis. Gene expression analysis confirmed the downregulation of QS-related genes, including cviI, cviR, vioA, vioB, and vioC, in fatty acid-treated C. violaceum. Additionally, we assessed the antimicrobial activity of C. violaceum-derived OMVs on Rhizobium sp., a PGPR and observed a marked reduction in bactericidal activity in the treated OMVs. This study suggests that LA and SA have potential as anti-infective agents to mitigate OMV-mediated virulence and combat antibiotic resistance in pathogens. [ABSTRACT FROM AUTHOR]

This study primarily aims to co-relate the health benefits of tea intake, an accessory dietary supplement as a preventive remedy against COVID-19 and the inclusion of derivatized polyphenols in addition to the alcohol based anti-viral disinfectants providing increased longevity. A methodical exploration of databases such as ScienceDirect, Taylor & Francis Online, and Google Scholar was conducted using a variety of keyword combinations. The abstracts of all the retrieved results were scrutinized, and any studies deemed irrelevant were excluded from further assessment. Tea Polyphenols have been known to contain several defensive phytochemical compounds namely catechins, theaflavins, tannins and flavonoids. Amongst these, catechins more particularly, Epigallocatechin gallate (EGCG), a major component of green tea along with its lipophilic derivatives and theaflavins from black tea account for additional biological significance. Recent literature and molecular simulation studies have reported their potency as anti-viral agents with their effectiveness against the SARS-CoV-2, commonly known as the novel coronavirus, causing global pandemic with several deaths worldwide. Further, we emphasize on the need to explore polyphenolic compounds as adjuvants with the approved class of drugs employed for combating the severe acute respiratory syndrome (SARS) virus. This would aid in developing a novel class of drugs with plant-based compounds adding to the cumulative effect against the viral infections. Although, EGCG has been studied extensively, in vitro, and in vivo clinical studies with respect to its anti-viral capability would necessarily provide a new horizon to the scientific and medical fraternity in formulating drugs with a higher ratio of natural to the synthetic counterparts, thereby decreasing toxicity. [ABSTRACT FROM AUTHOR]

Bacterial biofilms communicate by a process called Quorum Sensing. Gram negative bacterial pathogens specifically talk through the production, detection, and response to the signal or autoinducer called Acyl Homoserine Lactones. Bacterial lactonases are important AHL hydrolysing or quorum quenching enzymes. The present study deals with ten endospore forming gram positive isolates of the saltern soil. Preliminary screening for Quorum Quenching activity with the QS Inhibition indicator strain Chromobacterium violaceum ATCC 12472, showed positive activity in four isolates namely TS2, TS16, TSAWB, and TS53B. AHL lactonase (AiiA) specific primers amplified Acyl Homoserine Lactone lactonase gene in the TSAWB genome alone. Phylogenetic relationship of the identified AiiATSAWB confirmed its evolutionary relationship with bacterial AiiA like AHL lactonase of the metallo-beta-lactamase super family. Our in vitro AHL hydrolysis assay under wide percentage (0-5) of salt solutions with TSAWB isolate and also its intracellular soluble protein fraction showed halotolerant AHL hydrolysis ability of the AiiATSAWB enzyme. In silico determination of putative tertiary structure, the ESBRI derived conserved salt bridges, aminoacid residue characterization with high mole percent of acidic and hydrophobic residues reaffirmed the halotolerant ability of the enzyme. So we propound the future use of purified AiiATSAWB, as hypertonic suspension for inhalation to substitute the action of inactivated host's paraoxonase in treating Pseudomonas aeruginosa infection in cystic fibrosis patients. [ABSTRACT FROM AUTHOR]

Breast cancer is the most common type of cancer and the second most common cause of death. Influential and widely accepted breast cancer prevention strategies are still elusive. Aspirin and other nonsteroidal anti-inflammatory drugs, such as ibuprofen, are frequently recommended to treat fever, pain, and inflammation. Studies have shown that these medications also have anticancer effects. A key target of tumor-targeted therapy has been discovered in recent years, and it is the PI3K/AKT/mTOR signalling pathway. In order for tumour cells to proliferate, develop, migrate, and survive, the PI3K/AKT/mTOR signalling system is essential. So, using in silico analysis, we chose to determine whether the NSAID Diclofenac and other phytochemicals have anticancer properties and also act as PI3K/AKT/mTOR inhibitors. We conducted docking analyses for the drugs diclofenac, piperine, naringin, eugenol, d-limonene, cinnamaldehyde, and curcumin versus the FDA-approved AKT/PI3K and mTOR inhibitors alpelisib, rapamycin, and afuresertib. Both bioactivity and ADMET profiling were done for these drugs. We concluded from our in silico analysis that diclofenac, d-limonene, and piperine do not contradict any of Lipinski's rules and can be effective AKT/PI3K/mTOR inhibitors. [ABSTRACT FROM AUTHOR]

Abstract  Proline-rich protein (PRP), a cell wall protein of plant, has been studied in many plant species. Yet, none of the PRPs has been functionally elucidated. Here we report a novel flower-specific PRP designated OsPRP3 from rice. Expression analysis showed that the OsPRP3 transcript was mainly present in rice flower and accumulated abundantly during the late stage of the flower development. To study the function of OsPRP3, we constructed and transformed a binary vector containing a full clone of OsPRP3 in sense orientation and also an RNAi vector to achieve overexpression and knockout of the gene, respectively. Our overexpression plants showed a significant increase in cold tolerance than the WT plants which is conferred by the accumulation of OsPRP3 protein during cold treatment. Further the microscopic analysis revealed that OsPRP3 enhances the cell wall integrity in the cold tolerant plant and confers cold-tolerance in rice. Microscopic analysis of the RNAi mutant flower revealed that blocking OsPRP3 function caused significant defects in floral organogenesis. Taken together, the results suggested that OsPRP3 is a cell wall protein, playing a crucial role in determining extracellular matrix structure of floral organs. [ABSTRACT FROM AUTHOR]

Membrane vesicle secretion was predicted earlier as a method of elimination of proteins, lipids, and RNA from the cell. At present vesicles are thought to be a brand-new type of intercellular communication and they are playing a crucial role in numerous physiological and pathological processes. However, in this expanding field, much remains unknown regarding the origin, biogenesis, secretion, target and fate of these vesicles. Vesicle research might become a more established field as a result of a complete understanding of the isolation and analysis techniques currently in use, making it possible to utilize membrane vesicles in therapeutic settings. Thus, standardization of the isolation of vesicles is in great need. This research article deals with the isolation and characterization of two distinct bacterial species-derived membrane vesicles namely, Lactobacillus acidophilus a human gut Bacterial MVs and Pseudomonas syringae, a model phytopathogen. [ABSTRACT FROM AUTHOR]

Astragalus used mainly in Chinese traditional medicine, and in some parts of other Asian countries like Japan. It is one of the fundamental herbs found among medicinal and food plants. The plant contains various beneficial compounds, which provide enormous benefits to human health, such as the improvisation of the immune system, and it prevents and helps in the treatments of many diseases. These compounds act against various diseases like cancer, heart disease, a neurodegenerative disorder, and kidney and urinary-related problems. These elements also perform some crucial activities like anti-microbial activity, anti-oxidative activity, anti-hypertensive effect, etc., which is the precursor for the cause of various diseases. The dried root or the root powder of the plant is widely used as a nutrient supplement and used in foodstuffs includes ice cream, jelly, mayonnaise, syrups, sauce, candies, etc. The bark, root, flower, and stem extracts used widely in cosmetics, such as skin protection and skin whitening. Astragalus membranaceus (AM) is a natural substitute for food, medicine, and cosmetic ingredients as it is always good to replace synthetic ones with natural compounds. Therefore, this review describes the importance of its biologically active molecules and their applications in different health benefits in various aspects. [ABSTRACT FROM AUTHOR]

Bacterial biofilms communicate by a process called Quorum Sensing. Gram negative bacterial pathogens specifically talk through the production, detection, and response to the signal or autoinducer called Acyl Homoserine Lactones. Bacterial lactonases are important AHL hydrolysing or quorum quenching enzymes. The present study deals with ten endospore forming gram positive isolates of the saltern soil. Preliminary screening for Quorum Quenching activity with the QS Inhibition indicator strain Chromobacterium violaceum ATCC 12472, showed positive activity in four isolates namely TS2, TS16, TSAWB, and TS53B. AHL lactonase (AiiA) specific primers amplified Acyl Homoserine Lactone lactonase gene in the TSAWB genome alone. Phylogenetic relationship of the identified AiiATSAWB confirmed its evolutionary relationship with bacterial AiiA like AHL lactonase of the metallo-beta-lactamase super family. Our in vitro AHL hydrolysis assay under wide percentage (0-5) of salt solutions with TSAWB isolate and also its intracellular soluble protein fraction showed halotolerant AHL hydrolysis ability of the AiiATSAWB enzyme. In silico determination of putative tertiary structure, the ESBRI derived conserved salt bridges, aminoacid residue characterization with high mole percent of acidic and hydrophobic residues reaffirmed the halotolerant ability of the enzyme. So we propound the future use of purified AiiATSAWB , as hypertonic suspension for inhalation to substitute the action of inactivated host's paraoxonase in treating Pseudomonas aeruginosa infection in cystic fibrosis patients., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)