Recent developments in bioreactor scale production of bacterial polyhydroxyalkanoates

Bioprocess and Biosystems Engineering - Polyhydroxyalkanoates (PHAs) are biological plastics that are sustainable alternative to synthetic ones. Numerous microorganisms have been identified as PHAs...     

Inducible reporter/driver lines for the Arabidopsis root with intrinsic reporting of activity state

Cell‐, tissue‐ or organ‐specific inducible expression systems are powerful tools for functional analysis of changes to the pattern, level or timing of gene expression. However, plant researchers lack standardised reagents that promote reproducibility across the community. Here, we report the development and functional testing of a Gateway‐based system for quantitatively, spatially and temporally controlling inducible gene expression in Arabidopsis that overcomes several drawbacks of the legacy systems. We used this modular driver/effector system with intrinsic reporting of spatio‐temporal promoter activity to generate 18 well‐characterised homozygous transformed lines showing the expected expression patterns specific for the major cell types of the Arabidopsis root; seed and plasmid vectors are available through the Arabidopsis stock centre. The system's tight regulation was validated by assessing the effects of diphtheria toxin A chain expression. We assessed the utility of Production of Anthocyanin Pigment 1 (PAP1) as an encoded effector mediating cell‐autonomous marks. With this shared resource of characterised reference driver lines, which can be expanded with additional promoters and the use of other fluorescent proteins, we aim to contribute towards enhancing reproducibility of qualitative and quantitative analyses.     

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.     

Community structure,spatial distribution,diversity and functional characterization of culturable endophytic fungi associated with Glycyrrhiza glabra L.

A total of 266 endophytic fungal isolates were recovered from 1019 tissue segments of Glycyrrhiza glabra collected from four different locations in the North-Western Himalayas. The endophytes grouped into 21 genera and 38 different taxa. The host had strong affinity for the genus Phoma, followed by Fusarium. The species richness was highest at the sub-tropical location, followed by the sub-temperate location and the temperate locations, respectively. The tissue specificity of endophytes was also evident. Some endophytes showed potential antimicrobial activity against phyto-pathogens indicating that they may be helpful to the host in evading pathogens. All the endophytic taxa produced the plant growth promoting hormone, indole acetic acid (IAA), though in varying concentrations. None of these endophytes caused any symptoms of disease in co-cultivation with the tissue cultured plants. Further, all the endophytes had a positive influence on the phenolic and flavonoid content of the host. Three endophytes, Stagonosporopsis cucurbitacearum, Bionectria sp. and Aspergillus terreus also increased the host root (rhizome) and shoot growth visibly. Such endophytes are potential candidates for developing endophyte-based technologies for sustainable cultivation and enhanced productivity of G. glabra. This is the first report of community structure and biological properties of fungal endophytes associated with G. glabra.     

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.     

Analysis of VEGF gene polymorphisms and serum VEGF protein levels contribution in polycystic ovary syndrome of patients

Vascular endothelial growth factor (VEGF) is a well-known factor in reproductive function and contributes to the pathogenesis of polycystic ovary syndrome (PCOS). Genetic variations in VEGFA gene were suggested to contribute alterations in VEGF secretion and PCOS. This study evaluated the association of VEGFA SNPs with altered VEGF secretion level and PCOS among ethnically-matched control women. This prospective case–control study was conducted from 2016 to 2018 and comprised of 55 women with PCOS and 52 control subjects. ELISA was used to measure VEGF levels; and various other related bio chemicals whereas the genotyping of VEGFA variants was performed through the analysis of nine SNPs of VEGF. PRL, E2, PRGE testosterone and glucose level were found to be insignificantly different. The levels of FSH, LH, LH/FSH, TT, insulin, SHBG and HOMA-IR were significantly higher in the study group. Among the nine tested variants of VEGF SNPs, two SNPs rs3025020 and rs833061, consisted of TT (Recessive and Dominant homozygous, respectively) which were marginally higher in test. The SNP rs1570360 had significantly higher GG allele (32.73%) which was recessive homozygous. There was no significant difference observed in genotype frequencies related to higher value of VEGF. The genotype frequencies for the studied SNPs were in alignment with Hardy–Weinberg equilibrium (HWE). The mean serum VEGF levels got significantly increased in PCOS group. No significant association was found between VEGF genotypes and its serum levels. VEGF levels in rs699947 (AA-major homozygous), rs3025039 (CC-major homozygous) and rs833061 (TT & CC-major & minor homozygous) genotypes were significantly higher in PCOS. The study results evidently proved that the allelic variants in genes may be a factor for PCOS and VEGF serum levels with respect to few SNP variants only. These findings indicated that VEGF may be involved in PCOS status and confirmed the previous association between genetic variants in VEGF, serum level of VEGF protein and PCOS.

     

N-(2-hydroxyphenyl)acetamide and its gold nanoparticle conjugation prevent glycerol-induced acute kidney injury by attenuating inflammation and oxidative injury in mice

Molecular and Cellular Biochemistry - The protective activity of N-(2-hydroxyphenyl)acetamide (NA-2) and NA-2-coated gold nanoparticles (NA-2-AuNPs) in glycerol-treated model of acute kidney injury...     

Moleculer dynamics simulaiton revealed reciever domain of Acinetobacter baumannii BfmR enzyme as the hot spot for future antibiotics designing

Acinetobacter baumannii is an alarming nosocomial pathogen that is resistant to multiple drugs. The pathogen is forefront of scientific attention because of high mortality and morbidity found for its complications in the past decade. As a consequence, identification of novel drug candidates and subsequent designing of novel chemical scaffolds is an imperative need of time. In the present study, we used a recently reported structure of BfmR enzyme and performed structure based virtual screening, MD simulation and binding free energies calculations. MD simulation revealed a profound movement of the best-characterized inhibitor towards the α4-β5-α5 face of the enzyme receiver domain, thus indicating its high affinity for this site compared to phosphorylation. Furthermore, it was observed that the enzyme and enzyme-inhibitor complex have high structure stability with mean RMSD of 1.2 and 1.1 Å, respectively. Binding free energy calculations for the complex unraveled high stability with MMGBSA score of ?26.21?kcal/mol and MMPBSA score of ?1.47?kcal/mol. Van der Waal energy was found highly favorable with value of ?30.25?kcal/mol and dominated significantly the overall binding energy. Furthermore, a novel WaterSwap assay was used to circumvent the limitations of MMGB/PBSA that complements the inhibitor affinity for enzyme active pocket as depicted by the low convergence of Bennett, TI and FEP algorithms. Results yielded from this study will not only give insight into the phenomena of inhibitor movement towards the enzyme receiver domain, but will also provide a useful baseline for designing derivatives with improved biological and pharmacokinetics profiles.

Communicated by Ramaswamy H. Sarma     

New N-benzhydrylpiperazine/1,3,4-oxadiazoles conjugates inhibit the proliferation,migration, and induce apoptosis in HeLa cancer cells via oxidative stress–mediated mitochondrial pathway

N-benzhydrylpiperazine and 1,3,4-oxadiazoles are pharmacologically active scaffolds which exhibits significant inhibitory growth effects against various cancer cells, however, antiproliferation effects and the underlying mechanism for inducing apoptosis for aforementioned scaffolds addressing HeLa cancer cells remains uncertain. In this study, N-benzhydrylpiperazine clubbed with 1,3,4-oxadiazoles ( 4a–4h ) were synthesized, subsequently characterized using high resolution spectroscopic techniques and eventually evaluated for their antiproliferation potential by inducing apoptosis in HeLa cancer cells. The MTT assay screening results revealed that among all, compound 4d ( N-benzhydryl-4-((5-(4-aminophenyl)-1,3,4-oxadiazol-2-yl)methyl)piperazine) in particular, exhibited IC ₅₀ value of 28.13 ± 0.21 μg/mL and significantly inhibited the proliferation of HeLa cancer cells in concentration-dependent manner. The in vitro anticancer assays for treated HeLa cells resulted in alterations in the cell morphology, reduction in colony formation, and inhibition of cell migration in concentration-dependent treatment. Furthermore, G2/M phase arrest, variations in the nuclear morphology, degradation of chromosomal DNA confirmed the ongoing apoptosis in treated HeLa cells. Increase in the expression of cytochrome C and caspase-3 confirmed the involvement of intrinsic mitochondrial pathway regulating the cell death. Also, elevation in reactive oxygen species level and loss of mitochondrial membrane potential signified that compound 4d induced apoptosis in HeLa cells by generating the oxidative stress. Therefore, compound 4d may act as a potent chemotherapeutic agent against human cervical cancer.