Biopesticides are natural, biologically occurring compounds that are used to control various agricultural pests infesting plants in forests, gardens, farmlands, etc. There are different types of biopesticides that have been developed from various sources. This paper underscores the utility of biocontrol agents composed of microorganisms including bacteria, cyanobacteria, and microalgae, plant-based compounds, and recently applied RNAi-based technology. These techniques are described and suggestions are made for their application in modern agricultural practices for managing crop yield losses due to pest infestation. Biopesticides have several advantages over their chemical counterparts and are expected to occupy a large share of the market in the coming period.

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Aromatic hydrocarbons constitute a major group of environmental pollutants. Bioremediation appears to be the only viable alternative for large-scale decontamination. A number of bacteria have been identified that can degrade a variety of xenobiotics. Extensive studies of the enzymes and genes involved in degradation of aromatic hydrocarbons have revealed that the degradative enzymes could be broadly grouped into two major categories, peripheral and ring-cleavage enzymes. The peripheral enzymes are the ones that catabolize the pollutants initially to a metabolite that is further degraded. A majority of peripheral enzymes are oxygenases that hydroxylate the aromatic compounds, rendering them susceptible to the enzymes of ring-cleavage pathway. The genes of ring-cleavage enzymes have been shown to be highly conserved between different bacterial species. Presently, a number of constraints limit the use of available strains for efficient bioremediation. This review describes the enzymes and genes involved in xenobiotic degradation and underscores the importance of understanding the expression and regulation of genes encoding peripheral enzymes and their intelligent manipulation using recombinant DNA technology for efficient degradation of aromatic compounds.

Food security has become a major concern worldwide in recent years due to ever increasing population. Providing food for the growing billions without disturbing environmental balance is incessantly required in the current scenario. In view of this, sustainable modes of agricultural practices offer better promise and hence are gaining prominence recently. Moreover, these methods have taken precedence currently over chemical-based methods of pest restriction and pathogen control. Adoption of Biological Control is one such crucial technique that is currently in the forefront. Over a period of time, various biocontrol strategies have been experimented with and some have exhibited great success and promise. This review highlights the different methods of plant-pathogen control, types of plant pathogens, their modus operandi and various biocontrol approaches employing a range of microorganisms and their byproducts. The study lays emphasis on the use of upcoming methodologies like microbiome management and engineering, phage cocktails, genetically modified biocontrol agents and microbial volatilome as available strategies to sustainable agricultural practices. More importantly, a critical analysis of the various methods enumerated in the paper indicates the need to amalgamate these techniques in order to improve the degree of biocontrol offered by them.

Histone modification is emerging as a major regulatory mechanism for modulating gene expression by altering the accessibility of transcription factors to DNA. This study unravels the relationship between histone H3 modifications and LDL receptor induction, focusing also on routes by which phosphorylation is mediated in human hepatoma HepG2 cells. We show that while histone H3 is constitutively acetylated at LDL receptor chromatin, 12-Otetradecanoylphorbol-13-acetate (TPA) causes rapid hyperphosphorylation of histone H3 on serine 10 (histone H3-Ser10), despite global reduction in its phosphorylation levels. Mechanisms for regulating gene expression in response to extracellular stimuli have been a focus of major research efforts for many years. It is now apparent that this is achieved by a variety of different signal transduction mechanisms, which have the net result of modifying and regulating transcription machinery and the chromatin environment at particular target genes. Two of the most extensively studied mechanisms of signaling into the nucleus involve mitogen-activated protein kinase (MAPK) cascades and protein kinase C (PKC). At present there are at least three main pathways that are defined according to the MAPK that is activated: i ) the p42/44 MAPK (also known as ERK-1/2) pathway; ii ) the p46/54 JNK (also known as JNK) pathway; and iii ) the p38 MAPK pathway (1-3). Mitogenic stimuli, such as 12-O -tetradecanoylphorbol-13-acetate (TPA), activate p42/44 MAPK very rapidly and strongly and elicit weaker activation of p46/54 JNK and p38 MAPK , whereas various stress stimuli and anisomycin activate p46/54 JNK and p38 MAPK pathways very strongly but produce little or no p42/44 MAPK activation. The signaling networks leading to the activation of MAPKs themselves and some of their downstream targets have been extensively studied. Activation of MAPK pathways leads ultimately to the phosphorylation of transcription factors bound to their regulatory elements and/or histones associated with the promoters of target genes. Likewise, PKCs are activated by many extracellular and intracellular signals, including TPA, and have been implicated in a multitude of physiological functions in the cell (4, 5). PKCs also constitute a large family of isoforms, each with distinct properties. Twelve distinct members have been discovered to date in mammalian cells and have been subdivided into three distinct subfamilies: conventional PKCs, including ␣ , ␤ 1 and the splice variant ␤ II, and ␥ ; the novel PKCs ␦ , , , and ; and the atypical PKCs and / .Abbreviations: ECL, enhanced chemiluminescence; histone H3-Ser10, histone H3 on serine 10; Lys14, lysine 14; MAPK, mitogen-activated protein kinase; MEK-1/2, mitogen/extracellular-regulated protein kinase kinase-1 and -2; PD98059, 2-(2