Lignocellulosic biomass, a rich and inexpensive source of fermentable and renewable carbon, is the most abundant material on earth. Microbial bioprocessing of lignocellulosic biomass to produce ...biofuels (bioethanol, biobutanol, biodiesel) is a sustainable blueprint to reduce our depleting energy reserves and carbon footprint. Saccharomyces cerevisiae, being an excellent industrial ethanologenic organism, is an ideal candidate to engineer as a consolidated bio-processing (CBP) host, a concept that integrates the different steps of cellulosic ethanol production, from hydrolysis of cellulose to glucose and fermentation of glucose to ethanol in one step. Owing to the developments in the field of genetic engineering and sequencing technologies, research in the past two decades have made pivotal achievements to realize CBP enabling yeast suited for industrial applications. However, overcoming major limitations such as incomplete substrate catabolism, low titres of heterologous protein expression, sub-optimal operational conditions and impediment due to toxic inhibitors/by-products accumulation is still challenging. This review focuses on the progress achieved in constructing S. cerevisiae to produce bioethanol in a CBP framework. The different techniques of developing cellulolytic yeast strains are initially explained followed by relevant strategies to tackle the key bottlenecks associated with the process. Additionally, engineering efforts towards designing hemicellulose-derived sugar utilizing yeast strains are discussed.
•Strategies to engineer yeast as a consolidated bioprocessing host to produce ethanol is outlined•Recent biotechnological advancements to overcome the key limitation of this strategy is reviewed•Future research directions for yeast-based bioethanol production are discussed
ATP-binding cassette (ABC) is one of the two major superfamilies of transporters present across the evolutionary scale. ABC superfamily members came to prominence due to their ability to extrude ...broad spectrum of substrates and to confer multi drug resistance (MDR). Overexpression of some ABC transporters in clinical isolates of Candida species was attributed to the development of MDR phenotypes. Among Candida species, Candida glabrata is an emerging drug resistant species in human fungal infections. A comprehensive analysis of such proteins in C. glabrata is required to untangle their role not only in MDR but also in other biological processes. Bioinformatic analysis of proteins encoded by genome of human pathogenic yeast C. glabrata identified 25 putative ABC protein coding genes. On the basis of phylogenetic analysis, domain organization and nomenclature adopted by the Human Genome Organization (HUGO) scheme, these proteins were categorized into six subfamilies such as Pleiotropic Drug Resistance (PDR)/ABCG, Multi Drug Resistance (MDR)/ABCB, Multi Drug Resistance associated Protein (MRP)/ABCC, Adrenoleukodystrophy protein (ALDp)/ABCD, RNase L Inhibitor (RLI)/ABCE and Elongation Factor 3 (EF3)/ABCF. Among these, only 18 ABC proteins contained transmembrane domains (TMDs) and were grouped as membrane proteins, predominantly belonging to PDR, MDR, MRP, and ALDp subfamilies. A comparative phylogenetic analysis of these ABC proteins with other yeast species revealed their orthologous relationship and pointed towards their conserved functions. Quantitative real time PCR (qRT-PCR) analysis of putative membrane localized ABC protein encoding genes of C. glabrata confirmed their basal expression and showed variable transcriptional response towards antimycotic drugs. This study presents first comprehensive overview of ABC superfamily proteins of a human fungal pathogen C. glabrata, which is expected to provide an important platform for in depth analysis of their physiological relevance in cellular processes and drug resistance.
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Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Background: Chronic pain after inguinal hernia repair is a common complication. This study compared the difference between Desarda repair and Lichtenstein repair for inguinal hernia in chronic groin ...pain. Methods: One hundred patients with unilateral uncomplicated inguinal hernia were randomised to either Desarda repair (n = 50) or Lichtenstein repair (n = 50) under local anaesthesia and were evaluated for pain postoperatively. Operative time, surgical complications, time to return to normal gait and work, and overall patient satisfaction were recorded. The patient was blinded to the procedure. Any pain at three months (numerical rating scale 1 or more) was considered chronic pain. Results: Mean operation time was approximately 5 minutes less for Desarda (p = 0.33). There was no significant difference in terms of pain level postoperatively between Lichtenstein and Desarda groups. Twenty-two (44%) patients in the Lichtenstein group had chronic pain, and twenty-one (45.7%) patients had chronic pain in the Desarda group (p = 0.871). No significant difference was observed in haematoma formation, wound infection, recurrence rate, seroma, or foreign body sensation. The mean time for patients to return to normal gait was approximately 0.5 day earlier for the Desarda group (p = 0.29). The mean time for patients to return to normal work was comparable (p = 0.99). Desarda group had a slightly higher satisfaction rate than the Lichtenstein group (9.1%). Conclusion: Desarda repair is not inferior to Lichtenstein repair in the short-term concerning complications or pain. Keywords: herniorrhaphy, hernia, inguinal hernia, numerical rating scale, postoperative pain
Xylitol has a wide range of applications in the pharmaceuticals, cosmetic, food and beverage industry. Microbial xylitol production reduces the risk of contamination and is considered as environment ...friendly and sustainable compared to the chemical method. In this study, random mutagenesis and genetic engineering approaches were employed to develop Candida tropicalis strains with reduced xylitol dehydrogenase (XDH) activity to eliminate co-substrate requirement for corn cob-based xylitol-ethanol biorefinery. The results suggest that when pure xylose (10% w/v) was fermented in bioreactor, the Ethyl methane sulfonate (EMS) mutated strain (C. tropicalis K2M) showed 9.2% and XYL2 heterozygous (XYL2/xyl2DELA::FRT) strain (C. tropicalis K21D) showed 16% improvement in xylitol production compared to parental strain (C. tropicalis K2). Furthermore, 1.5-fold improvement (88.62 g/L to 132 g/L) in xylitol production was achieved by C. tropicalis K21D after Response Surface Methodology (RSM) and one factor at a time (OFAT) applied for media component optimization. Finally, corncob hydrolysate was tested for xylitol production in biorefinery mode, which leads to the production of 32.6 g/L xylitol from hemicellulosic fraction, 32.0 g/L ethanol from cellulosic fraction and 13.0 g/L animal feed. This work, for the first time, illustrates the potential of C. tropicalis K21D as a microbial cell factory for efficient production of xylitol and ethanol via an integrated biorefinery framework by utilising lignocellulosic biomass with minimum waste generation.
In the present study, the effect of colonization of different doses of T. harzianum Th-56 strain in rice genotypes were evaluated under drought stress. The rice genotypes treated with increasing dose ...of T. harzianum strain Th-56 showed better drought tolerance as compared with untreated control plant. There was significant change in malondialdehyde, proline, higher superoxide dismutase level, plant height, total dry matter, relative chlorophyll content, leaf rolling, leaf tip burn, and the number of scorched/senesced leaves in T. harzianum Th-56 treated rice genotypes under drought stress. This was corroborated with altered expression of aquaporin and dehydrin genes in T. harzianum Th-56 treated rice genotypes. The present findings suggest that a dose of 30 g/L was the most effective in improving drought tolerance in rice, and its potential exploitation will contribute to the advancement of rice genotypes to sustain crop productivity under drought stress. Interaction studies of T. harzianum with three aromatic rice genotypes suggested that PSD-17 was highly benefitted from T. harzianum colonization under drought stress.
Paf1 complex (Paf1C) is a transcription elongation factor whose recruitment is stimulated by Spt5 and the CDKs Kin28 and Bur1, which phosphorylate the Pol II C‐terminal domain (CTD) on Serines 2, 5, ...and 7. Bur1 promotes Paf1C recruitment by phosphorylating C‐terminal repeats (CTRs) in Spt5, and we show that Kin28 enhances Spt5 phosphorylation by promoting Bur1 recruitment. It was unclear, however, whether CTD phosphorylation by Kin28 or Bur1 also stimulates Paf1C recruitment. We find that Paf1C and its Cdc73 subunit bind diphosphorylated CTD repeats (pCTD) and phosphorylated Spt5 CTRs (pCTRs) in vitro, and that cdc73 mutations eliminating both activities reduce Paf1C recruitment in vivo. Phosphomimetic (acidic) substitutions in the Spt5 CTR sustain high‐level Paf1C recruitment in otherwise wild‐type cells, but not following inactivation of Bur1 or Kin28. Furthermore, inactivating the pCTD/pCTR‐interaction domain (PCID) in Cdc73 decreases Paf1C‐dependent histone methylation in cells containing non‐phosphorylatable Spt5 CTRs. These results identify an Spt5 pCTR‐independent pathway of Paf1C recruitment requiring Kin28, Bur1, and the Cdc73 PCID. We propose that pCTD repeats and Spt5 pCTRs provide separate interaction surfaces that cooperate to ensure high‐level Paf1C recruitment.
The Paf1 complex, a regulator of co‐transcriptional processes, is recruited to coding regions by a novel Spt5‐independent mechanism, involving RNA Polymerase CTD phosphorylation by the Kin28 and Bur1 kinases.
Colorectal cancer is the second leading cause of cancer deaths worldwide and has engrossed researchers' attention toward its detection and prevention at early stages. Primarily associated with ...genetic and environmental risk factors, the disease has also shown its emergence due to dysbiosis in microbiota. The microbiota not only plays a role in modulating the metabolisms of metastatic tissue but also has a keen role in cancer therapy. The immune cells are responsible for secreting various chemokines and cytokines, and activating pattern recognition receptors by different microbes can lead to the trail by which these cells regulate cancer. Furthermore, mixed immune reactions involving NK cells, tumor-associated macrophages, and lymphocytes have shown their connection with the microbial counterpart of the disease. The microbes like Bacteroides fragilis, Fusobacterium nucleatum, and Enterococcus faecalis and their metabolites have engendered inflammatory reactions in the tumor microenvironment. Hence the interplay between immune cells and various microbes is utilized to study the changing metastasis stage. Targeting either immune cells or microbiota could not serve as a key to tackling this deadly disorder. However, harnessing their complementation towards the disease can be a powerful weapon for developing therapy and diagnostic/prognostic markers. In this review, we have discussed various immune reactions and microbiome interplay in CRC, intending to evaluate the effectiveness of chemotherapy and immunotherapy and their parallel relationship.
This research work focuses on the potential application of an organic compound, santalol, obtained from santalum album, in the inhibition of the enzyme tyrosinase, which is actively involved in the ...biosynthesis of melanin pigment. Over-production of melanin causes undesirable pigmentation in humans as well as other organisms and significantly downgrades their aesthetic value. The study is designed to explain the purification of tyrosinase from the mushroom
, followed by activity assays and enzyme kinetics to give insight into the santalol-modulated tyrosinase inhibition in a dose-dependent manner. The multi-spectroscopic techniques such as UV-vis, fluorescence, and isothermal calorimetry are employed to deduce the efficiency of santalol as a potential candidate against tyrosinase enzyme activity. Experimental results are further verified by molecular docking. Santalol, derived from the essential oils of santalum album, has been widely used as a remedy for skin disorders and a potion for a fair complexion since ancient times. Based on enzyme kinetics and biophysical characterization, this is the first scientific evidence where santalol inhibits tyrosinase, and santalol may be employed in the agriculture, food, and cosmetic industries to prevent excess melanin formation or browning.
Spike fertility and associated traits are key factors in deciding the grain yield potential of wheat. Genome-wide association study (GWAS) interwoven with advanced post-GWAS analysis such as a ...genotype-phenotype network (geno-pheno network) for spike fertility, grain yield, and associated traits allow to identify of novel genomic regions and represents attractive targets for future marker-assisted wheat improvement programs. In this study, GWAS was performed on 200 diverse wheat genotypes using Breeders' 35K Axiom array that led to the identification of 255 significant marker-trait associations (MTAs) (
≥ 3) for 15 metric traits phenotyped over three consecutive years. MTAs detected on chromosomes 3A, 3D, 5B, and 6A were most promising for spike fertility, grain yield, and associated traits. Furthermore, the geno-pheno network prioritised 11 significant MTAs that can be utilised as a minimal marker system for improving spike fertility and yield traits. In total, 119 MTAs were linked to 81 candidate genes encoding different types of functional proteins involved in various key pathways that affect the studied traits either way. Twenty-two novel loci were identified in present GWAS, twelve of which overlapped by candidate genes. These results were further validated by the gene expression analysis, Knetminer, and protein modelling. MTAs identified from this study hold promise for improving yield and related traits in wheat for continued genetic gain and in rapidly evolving artificial intelligence (AI) tools to apply in the breeding program.
Semiconducting metal oxides are attractive material candidates for combustible gas sensors. Little or marginal base resistance drift of these metal oxide sensors is desirable during repeated response ...and recovery cycles. However, due to the partial recovery, often a significant drift in base resistance is observed. The gas sensing is termed irreversible when there is a partial recovery of base resistance, whereas for reversible sensing the base resistance is fully recovered. For reducing gas (hydrogen and carbon monoxide) sensing we have reported reversible and irreversible resistance transients for magnesium zinc ferrite and zinc oxide sensing elements, respectively. For a wide range of gas concentrations and operating temperatures, the response transients for these sensing elements are modelled using the Langmuir-Hinshelwood reaction mechanism. It is revealed that for irreversible-type sensing, the response time is reduced with the increase in test gas concentration. On the other hand, for reversible-type sensing, the response time is found to be independent of the gas concentration. Based on the estimation of pore size, pore size distribution and specific surface area of the calcined powder together with the analyses of the surface morphology of the sensing elements we have argued that due to the porous morphology of the magnesium zinc ferrite sensing element the oxidized product can easily desorb from the sensor during recovery. Therefore, irrespective of the test gas concentration, the base resistance of the magnesium zinc ferrite sensor recovers fully during the recovery process.
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