Modifying bio-catalytic properties of enzymes for efficient biocatalysis: a review from immobilization strategies viewpoint

Enzyme-based catalysis has become one of the most important disciplines in organic synthesis and plays a noteworthy role in the establishment of many chemical industries, e.g. fine chemicals, food or energy, textiles, agricultural, cosmeceutical, medicinal and pharmaceutical industries. However, pristine enzymes fail to demonstrate requisite functionalities for an industrial setting where extremely specific and stable catalysts are required. Immobilization enhances the catalytic stability and activity of enzymes and trims the overall cost burden of the enzyme. Therefore, it widely endeavours for proficient, sustainable, and environmentally responsive catalytic processes. Amongst several immobilization strategies, e.g. (1) supports-assisted, i.e. physical or covalent coupling and (2) supports-free techniques, i.e. cross-linked enzyme crystals (CLECs) or aggregates are the most promising ones and widely pursued for enzyme immobilization purposes. This perspective review focuses on up-to-date developments in the area of enzyme immobilization and presents their potentialities to upgrade and/or modify enzyme properties. Both types of immobilization strategies, i.e. supports-assisted and supports-free techniques are discussed with particular reference to CLECs or aggregates and protein-coated microcrystals. Also, several useful traits achieved after immobilization are also discussed in the second half of the review.     

Recent Advances of Using Ionic Liquids for Biopolymer Extraction and Processing

The evolution of petroleum‐derived polymers is one of the crowning accomplishments of the past century. Although the significant economic gains from this industrial model of resource utilization are achieved, the environmental impacts are fatal. One of the principles of sustainable development is to replace such polymers with potential alternatives derived from renewable materials. Biopolymers derived from natural resources afford a new, versatile, environmentally benign feedstock that could exhibit closed‐loop life cycles as part of a future material's industrial ecology. However, the solubility and processability of biopolymer materials provoke a serious bottleneck owing to their dense networks of inter ‐ and intramolecular bondings and structural heterogeneity. Recently, ionic liquids (ILs) have emerged as promising green solvents and acquired augmented appreciation for their peerless power of biopolymer processing. Among the fourteen principle of green chemistry, the two key elements encourage the exploitation of renewable raw materials by using environmentally benign solvents that cover in dissolution of biopolymers using ILs. This mini review represents a brief overview of the comprehensive ILs assisted extraction and processing of various biopolymeric materials for value‐added applications.     

Identification of novel high-frequency DNA methylation changes in breast cancer

Recent data have revealed that epigenetic alterations, including DNA methylation and chromatin structure changes, are among the earliest molecular abnormalities to occur during tumorigenesis. The inherent thermodynamic stability of cytosine methylation and the apparent high specificity of the alterations for disease may accelerate the development of powerful molecular diagnostics for cancer. We report a genome-wide analysis of DNA methylation alterations in breast cancer. The approach efficiently identified a large collection of novel differentially DNA methylated loci (approximately 200), a subset of which was independently validated across a panel of over 230 clinical samples. The differential cytosine methylation events were independent of patient age, tumor stage, estrogen receptor status or family history of breast cancer. The power of the global approach for discovery is underscored by the identification of a single differentially methylated locus, associated with the GHSR gene, capable of distinguishing infiltrating ductal breast carcinoma from normal and benign breast tissues with a sensitivity and specificity of 90% and 96%, respectively. Notably, the frequency of these molecular abnormalities in breast tumors substantially exceeds the frequency of any other single genetic or epigenetic change reported to date. The discovery of over 50 novel DNA methylation-based biomarkers of breast cancer may provide new routes for development of DNA methylation-based diagnostics and prognostics, as well as reveal epigenetically regulated mechanism involved in breast tumorigenesis.     

A multiscale probabilisitic framework to model early steps in tumor metastasis

Tumor metastasis is the leading cause of nearly all cancer related deaths. While several experimental and computational studies have addressed individual stages of the complex metastasis process, a comprehensive systems-biology model that links various stages of metastasis has not been put forth as of yet. In this paper we discuss the formulation and application of such a model that utilizes basic principles of cell biology, physics and mechanics to study the migratory patterns of tumor cells as they move from the parent tumor site to the connective tissue via the basement membrane. The model is first of its kind in capturing the essential early features of metastasis in a single simulation and shows good agreement with recent experimental studies.     

Blockchain based secure,efficient and coordinated energy trading and data sharing between electric vehicles

Cluster Computing - In this study, a secure and coordinated blockchain based energy trading system for Electric Vehicles (EVs) is presented. The major goals of this study are to provide secure and...     

The genetic drivers for the successful invasive potential of a generalist bird,the House crow

Biological Invasions - What kind of genetic structure helps the rapid range expansion of the invasive species is fundamental to understand spread of invasion. The House crow (Corvus splendens), an...     

Hexose monophosphate shunt,the role of its metabolites and associated disorders: A review

The hexose monophosphate (HMP) shunt acts as an essential component of cellular metabolism in maintaining carbon homeostasis. The HMP shunt comprises two phases viz. oxidative and nonoxidative, which provide different intermediates for the synthesis of biomolecules like nucleotides, DNA, RNA, amino acids, and so forth; reducing molecules for anabolism and detoxifying the reactive oxygen species during oxidative stress. The HMP shunt is significantly important in the liver, adipose tissue, erythrocytes, adrenal glands, lactating mammary glands and testes. We have researched the articles related to the HMP pathway, its metabolites and disorders related to its metabolic abnormalities. The literature for this paper was taken typically from a personal database, the Cochrane database of systemic reviews, PubMed publications, biochemistry textbooks, and electronic journals uptil date on the hexose monophosphate shunt. The HMP shunt is a tightly controlled metabolic pathway, which is also interconnected with other metabolic pathways in the body like glycolysis, gluconeogenesis, and glucuronic acid depending upon the metabolic needs of the body and depending upon the biochemical demand. The HMP shunt plays a significant role in NADPH₂ formation and in pentose sugars that are biosynthetic precursors of nucleic acids and amino acids. Cells can be protected from highly reactive oxygen species by NADPH ₂. Deficiency in the hexose monophosphate pathway is linked to numerous disorders. Furthermore, it was also reported that this metabolic pathway could act as a therapeutic target to treat different types of cancers, so treatments at the molecular level could be planned by limiting the synthesis of biomolecules required for proliferating cells provided by the HMP shunt, hence, more experiments still could be carried out to find additional discoveries.     

Glutamine Synthetase (GS): A Key Enzyme for Nitrogen Assimilation in The Macroalga Gracilariopsis lemaneiformis (Rhodophyta)

This study aimed to address the importance of glutamine synthetase II (GSII) during nitrogen assimilation in macroalga Gracilariopsis lemaneiformis. The cDNA full‐length sequence of the three glGSII genes was revealed to have the 5′ m⁷G cap, 5′‐untranslated region, open reading frame (ORF), 3′‐untranslated region, and a 3′ poly (A) tail. The three glGSIIs were classified into plastid glGS2 and cytosolic glGS1‐1 and glGS1‐2, having conserved GSII domains but different cDNA sequences. The complicated 5′ end flanking region indicates complex function of glGS genes. glGS1 genes were significantly up‐regulated under the different NH₄⁺: NO₃^? ratio (i.e., 40:10, 25:25, 10:40, and 0:50) except glGS2 which dramatically up‐regulated under the low NH₄⁺: NO₃^? ratio (i.e., 10:40 and 0:50) during different cultivation times. These different expression patterns perhaps are due to the different biological roles of GS1 and GS2 in the gene family. Furthermore, hypothetical working model of nitrogen assimilation pathway exhibiting the role of glGS1 and glGS2 is proposed. Finally, glGS2 was expressed in Escherichia coli BL21 (DE3), and the optimal conditions for culture (15°C, overnight), purification (500 mM imidazole washing), and activity (pH 7.4, 37°C) were established. This study lays a very important foundation for exploring the role of GS in nitrogen assimilation in algae and plants.