Aberrant STAT1 methylation as a non-invasive biomarker in blood of HCV induced hepatocellular carcinoma.

BACKGROUND: Hepatocellular carcinoma (HCC) is one of the most common types of cancer in the world and a reason behind different oncogenes activation and tumor suppressor genes inactivation. Hyper-methylation of tumor suppressor genes including RASSF1a, GSTP1, p16, and APC cause gene silencing as well as tumor cell invasion. STAT 1 gene is a part of signaling cascade of JAK/STAT and any dysregulation in signaling has been implicated in tumor formation. OBJECTIVE: The current investigation focus on the methylation role of STAT1 gene as a non-invasive biomarker in the progression and diagnosis of hepatocellular carcinoma. METHODS: STAT1 gene methylation status in 46 HCV induced hepatocellular carcinoma patients and 40 non-HCC controls were examined by methylation specific PCR. STAT1 gene expression was examined by real time PCR and further validated by various bioinformatics tools. RESULTS: STAT1 methylation in HCV-induced HCC (67.4%) was significantly higher compared to the non-HCC controls (p< 0.01). However, mRNA expression of STAT1 gene in methylated groups was significantly lower compared to unmethylated groups (p< 0.05). Furthermore, insilco analysis of STAT1 validated our results and shown expression of STAT1 mRNA was lower in liver cancer with the median 24.3 (p= 0.085). CONCLUSION: After using peripheral blood samples we observed that STAT1 silencing caused by aberrant methylation could be used as potential non-invasive biomarker for the diagnosis of HCV induced hepatocellular carcinoma. We conclude that blood as a sample source could be used instead of biopsy for early detection of HCC.

Biosynthesis of silver nanoparticles for the fabrication of non cytotoxic and antibacterial metallic polymer based nanocomposite system.

Nanomaterials have significantly contributed in the field of nanomedicine as this subject matter has combined the usefulness of natural macromolecules with organic and inorganic nanomaterials. In this respect, various types of nanocomposites are increasingly being explored in order to discover an effective approach in controlling high morbidity and mortality rate that had triggered by the evolution and emergence of multidrug resistant microorganisms. Current research is focused towards the production of biogenic silver nanoparticles for the fabrication of antimicrobial metallic-polymer-based non-cytotoxic nanocomposite system. An ecofriendly approach was adapted for the production of silver nanoparticles using fungal biomass (Aspergillus fumigatus KIBGE-IB33). The biologically synthesized nanoparticles were further layered with a biodegradable macromolecule (chitosan) to improve and augment the properties of the developed nanocomposite system. Both nanostructures were characterized using different spectrographic analyses including UV-visible and scanning electron microscopy, energy dispersive X-ray analysis, dynamic light scattering, and Fourier transform infrared spectroscopic technique. The biologically mediated approach adapted in this study resulted in the formation of highly dispersed silver nanoparticles that exhibited an average nano size and zeta potential value of 05 nm (77.0%) and - 22.1 mV, respectively with a polydispersity index of 0.4. Correspondingly, fabricated silver-chitosan nanocomposites revealed a size of 941 nm with a zeta potential and polydispersity index of + 63.2 mV and 0.57, respectively. The successful capping of chitosan on silver nanoparticles prevented the agglomeration of nanomaterial and also facilitated the stabilization of the nano system. Both nanoscopic entities exhibited antimicrobial potential against some pathogenic bacterial species but did not displayed any antifungal activity. The lowest minimal inhibitory concentration of nanocomposite system (1.56 µg ml-1) was noticed against Enterococcus faecalis ATCC 29212. Fractional inhibitory concentration index of the developed nanocomposite system confirmed its improved synergistic behavior against various bacterial species with no cytotoxic effect on NIH/3T3 cell lines. Both nanostructures, developed in the present study, could be utilized in the form of nanomedicines or nanocarrier system after some quantifiable trials as both of them are nonhazardous and have substantial antibacterial properties.

Structural elucidation and cytotoxic analysis of a fructan based biopolymer produced extracellularly by Zymomonas mobilis KIBGE-IB14.

Fructan based biopolymers have been extensively characterized and explored for their potential applications. Linear chained biopolymers, like levan-type fructan, have gained attention because they have exhibited unconventional stretchable and unbendable properties along with biodegradable and biocompatible nature. Current study deals with the chemical characterization and cytotoxic analysis of fructose based exopolysaccharide that was extracellularly produced by an indigenously isolated bacterial species (Zymomonas mobilis KIBGE-IB14). Maximum yield of exopolysaccharide (44.7 gL-1) was attained after 72 h of incubation at 30 °C under shaking conditions (180 rpm) when the culture medium was supplemented with 150.0 gL-1 of sucrose as a sole carbon source. This exopolysaccharide displayed high water solubility index (96.0%) with low water holding capacity (17.0%) and an intrinsic viscosity of about 0.447 dL g-1. This biopolymer exhibited a characteristic linear homopolysaccharide structure of levan when characterized using Fourier Transform Infrared (FTIR), Nuclear Magnetic Resonance (NMR) spectroscopy (1H, 13C, TOCSY and NOESY) while, Atomic Force Microscopy (AFM) revealed its pointed and thorny structure. The decomposition temperature of levan was approximately 245 °C as revealed by Thermal Gravimetric Analysis (TGA). X-Ray Diffraction (XRD) results revealed its amorphous nature with crystalline phase. Cytotoxicity of different concentrations of levan was investigated against mouse fibroblast cell lines by measuring their cellular metabolic activity and it was noticed that a higher concentration of levan (2.0 mg ml-1) permitted the normal cell growth of NIH/3T3 cell lines. This non-cytotoxic and biocompatible nature suggests that this levan has the capability to be utilized in food and drug-based formulations as it exhibited biomedical potential.

Bioprospecting of indigenous resources for the exploration of exopolysaccharide producing lactic acid bacteria.

Exploration of biodiversity lead towards the discovery of novel exopolysaccharide (EPS) producing microbes that have multiple applications. The safety compatibility status of lactic acid bacteria (LAB) makes it an attractive candidate for the production of EPS in industries. Therefore, new bacterial isolates are continuously being identified from different habitats. Current research was conducted to explore indigenous biodiversity for the production of dextransucrase, which is involved in the synthesis of dextran. Dextran is an EPS which is used in different industries. In this study, thirty-nine LAB were isolated from different food samples. The isolates were identified as genus Leuconostoc, Weissella and Streptococcus based on genotypic and phenotypic characteristics. Screening revealed that only eight isolates can produce dextransucrase in high titres. Fermentation conditions of dextran producing LAB was optimized. The results indicated that Weissella confusa exhibited maximum specific activity (1.50 DSU mg-1) in 8 h at 25 °C with pH 7.5. Dextran produced from Weissella proved to be a useful alternative to commercially used dextran produced by Leuconostoc mesenteroides in industries for various applications.

Hyper-production of levansucrase from Zymomonas mobilis KIBGEIB14 using submerged fermentation technique.

The industrial utilization of enzymes requires the high yield of enzyme production for the synthesis of polymers by microorganisms. Therefore, it is necessary to optimize different production parameters of levansucrase in order to increase its industrial applications. Zymomonas mobilis KIBGE-IB14 was considered as a promising candidate for the large scale production of levan among wide range of microorganisms. The current investigation is aimed to optimize the production parameters of levansucrase by Z. mobilis KIBGE-IB14 isolated from molasses. The results indicated that bacterial growth as well as enzyme production was greatly influenced by both physical and chemical conditions. It was revealed that high enzyme titers were achieved at 30°C with pH 6.5 after 24 hours of incubation in a modified medium. Moreover, the enzyme exhibited its induction in the presence of sucrose used as a substrate. Thus, the present study demonstrated that newly isolated Z. mobilis KIBGE-IB14 can be used as a plausible producer of levansucrase for industrial applications.

DNA methyltransferase 1, 3a, and 3b expression in hepatitis C associated human hepatocellular carcinoma and their clinicopathological association.

Identification of biomarker will obligate a substantial influence on various cancer management and treatment. We hypothesize that genetic/proteomic and epigenetic studies should be uncovering modifications which may be independently or jointly affect the expression of the genes that are involved in the progression of liver cancer (LC). For this purpose, we examined the effect of expressional changes of DNMTs on HCV infected LC of different genotypes. We found that both mRNA and protein expression levels of DNMT1, 3a, and 3b were upregulated in genotype 1b and 3a HCV infected patients as compared to control. However, DNMT3b mRNA levels did not change in genotypes 2a, 3, and 4, but were upregulated at the protein level by genotype 1b, 2a, and 3a. Furthermore, no significant changes were observed for DNMTs investigated in sample expressing the genotypes 5 and 6. Our findings suggest that HCV at least in part by altering DNMTs expression may play a significant role in HCC progression.

Introducing differential expression of human heat shock protein 27 in hepatocellular carcinoma: moving toward identification of cancer biomarker.

Previously, it has to be acknowledged that overexpressed heat shock protein B27 (HSPB27) have been implicated in the etiology of wide range of human cancers. However, the molecular mechanism leading to the disease initiation to progression in liver cancer is still unknown. Present work was undertaken to investigate the differentially expressed HSPB27 in association with those damages that lead to liver cancer development. For the identification of liver cancer biomarker, samples were subjected to comparative proteomic analysis using two-dimensional gel electrophoresis (2-DE) and were further validated by Western blot and immunohistochemical analysis. After validation, in silico studies were applied to demonstrate the significantly induced phosphorylated and S-nitrosylated signals. The later included the interacting partner of HSPB27, i.e., mitogen-activated protein kinase-3 and 5 (MAPK3 and 5), ubiquitin C (UBC), v-akt murine thymoma viral oncogene homolog 1 (AKT1), mitogen-activated protein kinase 14 (MAPK14), and tumor protein p53 (TP53), which bestowed with critical capabilities, namely, apoptosis, cell cycling, stress activation, tumor suppression, cell survival, angiogenesis, proliferation, and stress resistance. Taking together, these results shed new light on the potential biomarker HSPB27 that overexpression of HSPB27 did lead to upregulation of their interacting partner that together demonstrate their possible role as a novel tumor progressive agent for the treatment of metastasis in liver cancer. HSPB27 is a promising diagnostic marker for liver cancer although further large-scale studies are required. Also, molecular profiling may help pave the road to the discovery of new therapies.

Plasmid borne BAC-IB17: Localization of a potential antibacterial positive marker (Bac+) encoded broad inhibitory spectrum bacteriocin.

Production of antimicrobial compounds is considered as ubiquitous anti-competitor strategy in bacterial ecosystem. Bacteriocins are heterogeneous; highly specific and efficient anti-competitor agents and the gene responsible for the production of bacteriocins mostly exist in an autosomal state and associated with plasmids. BAC-IB17 is a broad spectrum bacteriocin and its production was observed at different stages of the growth cycle from Bacillus subtilis KIBGE-IB17. Growth kinetics of B. subtilis KIBGE-IB17 along with the production of BAC-IB17 showed that it exhibited secondary metabolite kinetics. Plasmid curing technique revealed that the gene responsible for the bacteriocinogenecity in B. subtilis KIBGE-IB17 was located on the plasmid of the bacterium. Overlay method also demonstrated the plasmid-mediated bacteriocinogenesis of the isolated colonies. With the advancement in genomics and proteomics, the plasmid borne BAC-IB17 can play a significant role in the transfer of bacteriocinogenic factor to other incompetent cells and also in the maintenance of plasmid in bacterial population.

Saccharification and liquefaction of cassava starch: an alternative source for the production of bioethanol using amylolytic enzymes by double fermentation process.

BACKGROUND: Cassava starch is considered as a potential source for the commercial production of bioethanol because of its availability and low market price. It can be used as a basic source to support large-scale biological production of bioethanol using microbial amylases. With the progression and advancement in enzymology, starch liquefying and saccharifying enzymes are preferred for the conversion of complex starch polymer into various valuable metabolites. These hydrolytic enzymes can selectively cleave the internal linkages of starch molecule to produce free glucose which can be utilized to produce bioethanol by microbial fermentation. RESULTS: In the present study, several filamentous fungi were screened for production of amylases and among them Aspergillus fumigatus KIBGE-IB33 was selected based on maximum enzyme yield. Maximum α-amylase, amyloglucosidase and glucose formation was achieved after 03 days of fermentation using cassava starch. After salt precipitation, fold purification of α-amylase and amyloglucosidase increased up to 4.1 and 4.2 times with specific activity of 9.2 kUmg⁻¹ and 393 kUmg⁻¹, respectively. Concentrated amylolytic enzyme mixture was incorporated in cassava starch slurry to give maximum glucose formation (40.0 gL⁻¹), which was further fermented using Saccharomyces cerevisiae into bioethanol with 84.0% yield. The distillate originated after recovery of bioethanol gave 53.0% yield. CONCLUSION: An improved and effective dual enzymatic starch degradation method is designed for the production of bioethanol using cassava starch. The technique developed is more profitable due to its fast liquefaction and saccharification approach that was employed for the formation of glucose and ultimately resulted in higher yields of alcohol production.

Structural analysis and characterization of dextran produced by wild and mutant strains of Leuconostoc mesenteroides.

An exopolysaccharide known as dextran was produced by Leuconostoc mesenteroides KIBGE-IB22 (wild) and L. mesenteroides KIBGE-IB22M20 (mutant). The structure was characterized using FTIR, (1)H NMR, (13)C NMR and 2D NMR spectroscopic techniques, whereas surface morphology was analyzed using SEM. A clear difference in the spectral chemical shift patterns was observed in both samples. All the spectral data indicated that the exopolysaccharide produced by KIBGE-IB22 is a mixture of two biopolymers. One was dextran in α-(1 → 6) configuration with a small proportion of α-(1 → 3) branching and the other was levan containing ß-(2 → 6) fructan fructofuranosyl linkages. However, remarkably the mutant only produced dextran without any concomitant production of levan. Study suggested that the property of KIBGE-IB22M20, regarding improved production of high molecular weight dextran in a shorter period of fermentation time without any contamination of other exopolysaccharide, could be employed to make the downstream process more feasible and cost effective on large scale.

Isolation and characterization of different strains of Bacillus licheniformis for the production of commercially significant enzymes.

Utilization of highly specific enzymes for various industrial processes and applications has gained huge momentum in the field of white biotechnology. Selection of a strain by efficient plate-screening method for a specific purpose has also favored and boosted the isolation of several industrially feasible microorganisms and screening of a large number of microorganisms is an important step in selecting a potent culture for multipurpose usage. Five new bacterial isolates of Bacillus licheniformis were discovered from indigenous sources and characterized on the basis of phylogeny using 16S rDNA gene analysis. Studies on morphological and physiological characteristics showed that these isolates can easily be cultivated at different temperatures ranging from 30°C to 55°C with a wide pH values from 3.0 to 11.0 All these 05 isolates are salt tolerant and can grow even in the presences of high salt concentration ranging from 7.0 to 12.0%. All these predominant isolates of B. licheniformis strains showed significant capability of producing some of the major industrially important extracellular hydrolytic enzymes including α-amylase, glucoamylase, protease, pectinase and cellulase in varying titers. All these isolates hold great potential as commercial strains when provided with optimum fermentation conditions.

Mutational analysis and characterization of dextran synthesizing enzyme from wild and mutant strain of Leuconostoc mesenteroides.

Dextransucrase producing Leuconostoc mesenteroides KIBGE IB-22 was subjected to mutagenesis by exposing the strain to UV irradiation. The dextransucrase produced by both the strains (wild and mutant) were characterized and the catalytic properties of both wild and mutant dextransucrase were compared. Among 42 mutants, KIBGE IB-22M20 exhibited 6.75 times increase in dextransucrase activity as compared to the wild one. Wild dextransucrase showed specific activity of 31.3 DSU/mg of protein with V(max) and K(m) of 18.84 DSU/ml/h and 77.09 mM, respectively at 30 °C in 0.3 M citrate buffer (pH 4.5) using sucrose as substrate. Whereas, mutant dextransucrase exhibited a specific activity of 173.2 DSU/mg with V(max) and K(m) values of 104.2DSU/ml/h and 101.7 mM, respectively at 35 °C in 0.3 M citrate buffer (pH 5.0) keeping the same substrate as for wild. Dextransucrase from both wild and mutant showed an approximate molecular weight of 221 kDa by SDS-PAGE.

Bacteriocin (BAC-IB17): screening, isolation and production from Bacillus subtilis KIBGE IB-17.

Bacteriocins are peptides produced by a variety of different microbes and have antimicrobial activity against closely related species. These antimicrobial agents are gaining more and more attention as an alternative therapeutics not only in pharmaceutical but also as a preservative in food industries. In this study several bacterial strains were isolated from soil and screened for bacteriocin production. Among them, one strain identified as Bacillus subtilis KIBGE IB-17 on the basis of taxonomic studies and confirmed by 16S rDNA analysis. This newly isolated strain showed antibacterial activity against several Gram positive and Gram negative bacteria. Different concentrations of tryptone, yeast extract and NaCl and physiochemical factors such as temperature, pH and incubation period were selected as variables for maximum production of bacteriocin by using agar well diffusion method and significant effects of variables were observed on the production of Bac-IB17. A newly designed modified TY medium showed maximum bacteriocin production containing 1.0% tryptone, 0.5% yeast extract and 0.5% NaCl. Maximum Bac-IB17 production was observed at 37° after 24 hours with initial medium pH 7.0. Bacillus subtilis KIBGE IB-17 is capable of producing a bacteriocin at a wide range of pH and temperature that makes it an ideal strain that can be used for the production of bacteriocin on industrial scale level. The identification and production of such bacteriocin like compound against a wide spectrum of microbial species is very important for food and pharmaceutical industry.

Characterization and potential applications of high molecular weight dextran produced by Leuconostoc mesenteroides AA1.

Different strains of Leuconostoc mesenteroides were isolated from indigenous sources that were capable of producing a commercially important long chain glucose polymer known as dextran. Dextran produced by L. mesenteroides AA1 was characterized. The physicochemical characteristics and structural analysis of dextran revealed that this biopolymer has many potential applications in several biotechnological industries and L. mesenteroides AA1 can be used for commercial production of dextran on large scale. Dextran produced by this strain is a high molecular weight glucose polymer with only α (1→6) branch linkage in the main backbone chain without any further branching with a viscosity of 2.23×103cp of 5.0% dextran solution. This high molecular weight dextran has an average molecular weight ranging from 10,000 to 40,000kDa. The key utility of dextran in different industries lies on its molecular weight and dextran produced by L. mesenteroides AA1 can be tailored to meet the requirement for any industry.