In silico and in vitro analysis of quorum quenching active phytochemicals from the ethanolic extract of medicinal plants against quorum sensing mediated virulence factors of Acinetobacter baumannii

Inhibition of quorum sensing called quorum quenching (QQ) is now extensively utilized in the prevention of bacterial infections. In the present study, in silico and in vitro analysis of quorum quenching (QQ) or anti-Quorum sensing (QS) activity of ethanolic extract of medicinal plants against QS mediated virulence factors of human pathogenic bacteria Acinetobacter baumannii has been investigated. The effect of plant extracts on QS by acyl homoserine lactone (AHL) has been carried out by quantification of secreted AHL by high-pressure liquid chromatography (HPLC). Measurement of QQ activity was determined by maximum inhibition of virulence factors and AHL production which was recorded in E. globules and A. indica extracts. In silico analysis was studied with possible bioactive compounds in the ethanolic extract of respective plant material that were characterized by gas chromatography equipped with mass spectroscopy (GCMS) against the enzyme responsible for the production of signaling molecule which mediates QS AHL synthase. Distinct reduction of all the QS-mediated virulence factors was recorded in the E. globules and A. indica. Among the different bioactive compounds, the ethanolic leaf extract of E. globules of GCMS analyzed compound, Hexadeconoic acid, 1-(hydroxymethyl), 1, 2-ethannediyl ester interacted with 1KZF protein (AHL synthase) and showed binding energy of −11.2 kcal/mol to MET 42 and TYR 54. Phytochemicals mediated inhibition of AHL synthase activity which was responsible for AHL production would suggest the possible utilization of plant extracts as an antibacterial agent to fight against disease-causing pathogenic bacteria

c-di-GMP Turn-Over in Clostridium difficile Is Controlled by a Plethora of Diguanylate Cyclases and Phosphodiesterases

Clostridium difficile infections have become a major healthcare concern in the last decade during which the emergence of new strains has underscored this bacterium's capacity to cause persistent epidemics. c-di-GMP is a bacterial second messenger regulating diverse bacterial phenotypes, notably motility and biofilm formation, in proteobacteria such as Vibrio cholerae, Pseudomonas aeruginosa, and Salmonella. c-di-GMP is synthesized by diguanylate cyclases (DGCs) that contain a conserved GGDEF domain. It is degraded by phosphodiesterases (PDEs) that contain either an EAL or an HD-GYP conserved domain. Very little is known about the role of c-di-GMP in the regulation of phenotypes of Gram-positive or fastidious bacteria. Herein, we exposed the main components of c-di-GMP signalling in 20 genomes of C. difficile, revealed their prevalence, and predicted their enzymatic activity. Ectopic expression of 31 of these conserved genes was carried out in V. cholerae to evaluate their effect on motility and biofilm formation, two well-characterized phenotype alterations associated with intracellular c-di-GMP variation in this bacterium. Most of the predicted DGCs and PDEs were found to be active in the V. cholerae model. Expression of truncated versions of CD0522, a protein with two GGDEF domains and one EAL domain, suggests that it can act alternatively as a DGC or a PDE. The activity of one purified DGC (CD1420) and one purified PDE (CD0757) was confirmed by in vitro enzymatic assays. GTP was shown to be important for the PDE activity of CD0757. Our results indicate that, in contrast to most Gram-positive bacteria including its closest relatives, C. difficile encodes a large assortment of functional DGCs and PDEs, revealing that c-di-GMP signalling is an important and well-conserved signal transduction system in this human pathogen

RNA Nanotechnology

Cite this entry as: Yaradoddi J.S. et al. (2019) RNA Nanotechnology. In: Martínez L., Kharissova O., Kharisov B. (eds) Handbook of Ecomaterials. Springer, Cham Publisher Name: Springer, Cham DOI: https://doi.org/10.1007/978-3-319-68255-6_193 Print ISBN: 978-3-319-68254-9 Online ISBN: 978-3-319-68255-6 First Online: 14 February 2019DNA, RNA, and proteins are seemed to be immensely substantial tools for nanobiotechnological applications; this is since their exceptional biochemical properties and role. Particularly RNA is categorized over comparatively high-temperature stability, varied organizational pliability, and their performance in natural circumstances. Above properties made, RNA, a valued constituent for bionanotechnology processes and usefulness, especially RNA nanotechnology, could synthesize complex molecules using simple molecules through de nova nanostructures having exceptional utility by the strategy, integration, and manipulations of most predominant processes which are usually based on different RNA structures and because of their vital biochemical properties. The current chapter emphasis on the basic principles inspires the normal design of RNA nanostructures, pronounces the important methods that are used in constructing nanoparticles’ self-assemblages, and further describes the associated challenges and excelled opportunities of RNA nanotechnology in near future.Peer reviewe

Lab-on-a-chip : a component view

Miniaturization is being increasingly applied to biological and chemical analysis processes. Lab-on-a-chip systems are direct creation of the advancement in the miniaturization of these processes. They offer a host of exciting applications in several areas including clinical diagnostics, food and environmental analysis, and drug discovery and delivery studies. This paper reviews lab-on-a-chip systems from their components perspective. It provides a categorization of the standard functional components found in lab-on-a-chip devices together with an overview of the latest trends and developments related to lab-on-a-chip technologies and their application in nanobiotechnology. The functional components include: injector, transporter, preparator, mixer, reactor, separator, detector, controller, and power supply. The components are represented by appropriate symbols allowing designers to present their lab-on-a-chip products in a standard manner. Definition and role of each functional component are included and complemented with examples of existing work. Through the approach presented in this paper, it is hoped that modularity and technology transfer in lab-on-a-chip systems can be further facilitated and their application in nanobiotechnology be expanded.<br /