Abstract:
BACKGROUND:Hepatitis C virus (HCV) is a common and leading cause for liver cirrhosis and hepatocellular carcinoma. Current therapies to treat HCV infection are shown to be partially effective and poorly tolerated. Therefore, ample efforts are underway to rationally design therapies targeting the HCV non-structural proteins. Most of the work carried out in this direction has been focusing mainly on HCV genotype 1. Two direct-acting antiviral agents (DAAs) Telaprevir and Boceprevir are being used against genotype 1a infection in combination therapy with interferon and ribavirin. Unfortunately these DAAs are not effective against genotype 3a. Considering the wide spread infection by HCV genotype 3a in developing countries especially South Asia, we have focused on the recombinant production of antiviral drug targets NS3 and NS5A from HCV genotype 3a. These protein targets are to be used for screening of inhibitors. RESULTS:High-level expression of NS3 and NS5A was achieved at 25°C, using ~1 and 0.5 mM Isopropyl β-D-1-thiogalactopyranoside (IPTG), respectively. Yields of the purified NS3 and NS5A were 4 and 1 mg per liter culture volume, respectively. Although similar amounts of purified NS3 were obtained at 25 and 14°C, specificity constant (Kcat/Km) was somewhat higher at expression temperature of 25°C. Circular dichroism (CD) and Fourier-transform infrared (FT-IR) spectroscopy revealed that both NS3 and NS5A contain a mixture of alpha-helix and beta-sheet secondary structures. For NS3 protein, percentages of secondary structures were similar to the values predicted from homology modeling. CONCLUSIONS:NS3 and NS5A were over-expressed and using Nickel-affinity method both proteins were purified to ~ 95% purity. Yield of the purified NS3 obtained is four fold higher than previous reports. CD spectroscopy revealed that difference in activity of NS3 expressed at various temperatures is not related to changes in global structural features of the protein. Moreover, CD and FT-IR analysis showed that NS3 and NS5A contain both alpha-helical and beta-sheet structures and for NS5A, the proportion is almost equal. The production of NS3 and NS5A in milligram quantities will allow their characterization by biophysical and biochemical means that will help in designing new strategies to fight against HCV infection.
journal_name
Microb Cell Factjournal_title
Microbial cell factoriesauthors
Anwar MI,Iqbal M,Yousef MS,Rahman Mdoi
10.1186/1475-2859-12-111subject
Has Abstractpub_date
2013-11-16 00:00:00pages
111issn
1475-2859pii
1475-2859-12-111journal_volume
12pub_type
杂志文章abstract:BACKGROUND:Chitinases are ubiquitous enzymes that have gained a recent biotechnological attention due to their ability to transform biological waste from chitin into valued chito-oligomers with wide agricultural, industrial or medical applications. The biological activity of these molecules is related to their size and...
journal_title:Microbial cell factories
pub_type: 杂志文章
doi:10.1186/s12934-018-0895-x
更新日期:2018-03-22 00:00:00
abstract:BACKGROUND:L-Ornithine is a non-protein amino acid with extensive applications in medicine and the food industry. Currently, L-ornithine production is based on microbial fermentation, and few microbes are used for producing L-ornithine owing to unsatisfactory production titer. RESULTS:In this study, Corynebacterium gl...
journal_title:Microbial cell factories
pub_type: 杂志文章
doi:10.1186/s12934-017-0776-8
更新日期:2017-09-22 00:00:00
abstract:BACKGROUND:D-Lactate is a valued chemical which can be produced by some bacteria including Klebsiella pneumoniae. However, only a few studies have focused on K. pneumoniae for D-lactate production with a significant amount of by-products, which complicated the purification process and decreased the yield of D-lactate. ...
journal_title:Microbial cell factories
pub_type: 杂志文章
doi:10.1186/s12934-017-0822-6
更新日期:2017-11-21 00:00:00
abstract:BACKGROUND:Extracts and products (roots and/or aerial parts) from Echinacea ssp. represent a profitable market sector for herbal medicines thanks to different functional features. Alkamides and polyacetylenes, phenols like caffeic acid and its derivatives, polysaccharides and glycoproteins are the main bioactive compou...
journal_title:Microbial cell factories
pub_type: 杂志文章
doi:10.1186/1475-2859-12-44
更新日期:2013-05-04 00:00:00
abstract:BACKGROUND:The characterization of the molecular determinants of metal resistance has potential biotechnological application in biosensing and bioremediation. In this context, the bacterium Thermus thermophilus HB27 is a metal tolerant thermophile containing a set of genes involved in arsenic resistance which, differen...
journal_title:Microbial cell factories
pub_type: 杂志文章
doi:10.1186/s12934-018-0918-7
更新日期:2018-05-18 00:00:00
abstract:BACKGROUND:Cholesterol, the precursor of all steroid hormones, is the most abundant steroid in vertebrates and exhibits highly hydrophobic properties, rendering it a difficult substrate for aqueous microbial biotransformations. In the present study, we developed a Bacillus megaterium based whole-cell system that allows...
journal_title:Microbial cell factories
pub_type: 杂志文章
doi:10.1186/s12934-015-0300-y
更新日期:2015-07-29 00:00:00
abstract:BACKGROUND:In Saccharomyces cerevisiae, alpha-glucosidase (maltase) is a key enzyme in maltose metabolism. In addition, the overexpression of the alpha-glucosidase-encoding gene MAL62 has been shown to increase the freezing tolerance of yeast in lean dough. However, its cryoprotection mechanism is still not clear. RES...
journal_title:Microbial cell factories
pub_type: 杂志文章
doi:10.1186/s12934-020-01454-6
更新日期:2020-10-19 00:00:00
abstract:BACKGROUND:Under aerobic conditions, acetic acid is the major byproduct produced by E. coli during the fermentation. And acetic acid is detrimental to cell growth as it destroys transmembrane pH gradients. Hence, how to reduce the production of acetic acid and how to utilize it as a feedstock are of intriguing interest...
journal_title:Microbial cell factories
pub_type: 杂志文章
doi:10.1186/s12934-016-0475-x
更新日期:2016-05-05 00:00:00
abstract:BACKGROUND:Cell surface display of recombinant proteins has become a powerful tool for biotechnology and biomedical applications. As a model eukaryotic microorganism, Saccharomyces cerevisiae is an ideal candidate for surface display of heterologous proteins. However, the frequently used commercial yeast surface displa...
journal_title:Microbial cell factories
pub_type: 杂志文章
doi:10.1186/s12934-019-1133-x
更新日期:2019-05-18 00:00:00
abstract:BACKGROUND:Despite the progressive miniaturization of bioreactors for screening purposes, shake flasks are still widespread in biotechnological laboratories and industry as cultivation vessels. Shake flasks are often applied as the first or second step in applications such as strain screening or media optimization. Thu...
journal_title:Microbial cell factories
pub_type: 杂志文章
doi:10.1186/s12934-016-0444-4
更新日期:2016-02-24 00:00:00
abstract:BACKGROUND:Ethanologenic alphaproteobacterium Zymomonas mobilis has been acknowledged as a promising biofuel producer. There have been numerous efforts to engineer this species applicable for an industrial-scale bioethanol production. Although Z. mobilis is robustly resilient to certain abiotic stress such as ethanol, ...
journal_title:Microbial cell factories
pub_type: 杂志文章
doi:10.1186/s12934-020-01406-0
更新日期:2020-07-20 00:00:00
abstract:BACKGROUND:Variations in codon usage between species are one of the major causes affecting recombinant protein expression levels, with a significant impact on the economy of industrial enzyme production processes. The use of codon-optimized genes may overcome this problem. However, designing a gene for optimal expressi...
journal_title:Microbial cell factories
pub_type: 杂志文章
doi:10.1186/1475-2859-10-15
更新日期:2011-03-03 00:00:00
abstract:BACKGROUND:Streptomycetes produce a plethora of natural products including antibiotics and anticancer drugs, as well as many industrial enzymes. Their mycelial life style is a major bottleneck for industrial exploitation and over decades strain improvement programs have selected production strains with better growth pr...
journal_title:Microbial cell factories
pub_type: 杂志文章
doi:10.1186/s12934-015-0224-6
更新日期:2015-04-01 00:00:00
abstract:BACKGROUND:Recombinant protein production is universally employed as a solution to obtain the milligram to gram quantities of a given protein required for applications as diverse as structural genomics and biopharmaceutical manufacture. Yeast is a well-established recombinant host cell for these purposes. In this study...
journal_title:Microbial cell factories
pub_type: 杂志文章
doi:10.1186/1475-2859-9-47
更新日期:2010-06-17 00:00:00
abstract:BACKGROUND:Bioethanol produced by the yeast Saccharomyces cerevisiae is currently one of the most promising alternatives to conventional transport fuels. Lignocellulosic hemicelluloses obtained after hydrothermal pretreatment are important feedstock for bioethanol production. However, hemicellulosic materials cannot be...
journal_title:Microbial cell factories
pub_type: 杂志文章
doi:10.1186/s12934-014-0145-9
更新日期:2014-10-12 00:00:00
abstract:BACKGROUND:Histamine is a key mediator of the anti-inflammatory activity conferred by the probiotic organism Lactobacillus reuteri ATCC PTA 6475 in animal models of colitis and colorectal cancer. In L. reuteri, histamine synthesis and secretion requires L-histidine decarboxylase and a L-histidine/histamine exchanger. C...
journal_title:Microbial cell factories
pub_type: 杂志文章
doi:10.1186/s12934-019-1264-0
更新日期:2019-12-12 00:00:00
abstract:BACKGROUND:Methane-utilizing bacteria (methanotrophs) are capable of growth on methane and are attractive systems for bio-catalysis. However, the application of natural methanotrophic strains to large-scale production of value-added chemicals/biofuels requires a number of physiological and genetic alterations. An accur...
journal_title:Microbial cell factories
pub_type: 杂志文章
doi:10.1186/s12934-015-0377-3
更新日期:2015-11-25 00:00:00
abstract:BACKGROUND:Calreticulin (CRT) resides in the endoplasmic reticulum (ER) and functions to chaperone proteins, ensuring proper folding, and intracellular Ca(2+) homeostasis. Emerging evidence shows that CRT is a multifunctional protein with significant roles in physiological and pathological processes with presence both ...
journal_title:Microbial cell factories
pub_type: 杂志文章
doi:10.1186/s12934-015-0356-8
更新日期:2015-10-15 00:00:00
abstract:BACKGROUND:The budding yeast Pichia pastoris is widely used for protein production. To determine the best suitable strategy for strain improvement, especially for high secretion, quantitative data of intracellular fluxes of recombinant protein are very important. Especially the balance between intracellular protein for...
journal_title:Microbial cell factories
pub_type: 杂志文章
doi:10.1186/1475-2859-10-47
更新日期:2011-06-26 00:00:00
abstract:BACKGROUND:A stereoisomer of inositol, scyllo-inositol (SI), has been regarded as a promising therapeutic agent for Alzheimer's disease. However, this compound is relatively rare, whereas another stereoisomer of inositol, myo-inositol (MI) is abundant in nature. Bacillus subtilis 168 has the ability to metabolize inosi...
journal_title:Microbial cell factories
pub_type: 杂志文章
doi:10.1186/s12934-017-0682-0
更新日期:2017-04-21 00:00:00
abstract:BACKGROUND:We evaluated the functional capacity of plantaricin-producing Lactobacillus plantarum SF9C and S-layer-carrying Lactobacillus brevis SF9B to withstand gastrointestinal transit and to compete among the gut microbiota in vivo. Considering the probiotic potential of Lb. brevis SF9B, this study aims to investiga...
journal_title:Microbial cell factories
pub_type: 杂志文章
doi:10.1186/s12934-020-01365-6
更新日期:2020-05-19 00:00:00
abstract:BACKGROUND:Amylases are used in various industrial processes and a key requirement for the efficiency of these processes is the use of enzymes with high catalytic activity at ambient temperature. Unfortunately, most amylases isolated from bacteria and filamentous fungi have optimal activity above 45 °C and low pH. For ...
journal_title:Microbial cell factories
pub_type: 杂志文章
doi:10.1186/s12934-017-0693-x
更新日期:2017-05-02 00:00:00
abstract:BACKGROUND:A reliable quenching and metabolite extraction method has been developed for Lactobacillus plantarum. The energy charge value was used as a critical indicator for fixation of metabolism. RESULTS:Four different aqueous quenching solutions, all containing 60% of methanol, were compared for their efficiency. O...
journal_title:Microbial cell factories
pub_type: 杂志文章
doi:10.1186/1475-2859-6-27
更新日期:2007-08-20 00:00:00
abstract:BACKGROUND:Indole pyruvic acid (IPA) is a versatile platform intermediate and building block for a number of high-value products in the pharmaceutical and food industries. It also has a wide range of applications, such as drugs for the nervous system, cosmetics, and luminophores. Chemical synthesis of IPA is a complica...
journal_title:Microbial cell factories
pub_type: 杂志文章
doi:10.1186/s12934-016-0620-6
更新日期:2017-01-03 00:00:00
abstract:BACKGROUND:Increasingly lignocellulosic biomass hydrolysates are used as the feedstock for industrial fermentations. These biomass hydrolysates are complex mixtures of different fermentable sugars, but also inhibitors and salts that affect the performance of the microbial production host. The performance of six industr...
journal_title:Microbial cell factories
pub_type: 杂志文章
doi:10.1186/1475-2859-8-64
更新日期:2009-12-04 00:00:00
abstract:BACKGROUND:Epimutations arising from transcriptional slippage seem to have more important role in regulating gene expression than earlier though. Since the level and the fidelity of transcription primarily determine the overall efficiency of gene expression, all factors contributing to their decrease should be identifi...
journal_title:Microbial cell factories
pub_type: 杂志文章
doi:10.1186/s12934-018-0999-3
更新日期:2018-09-21 00:00:00
abstract:BACKGROUND:Bacillus subtilis is an important industrial workhorse applied in the production of many different commercially relevant proteins, especially enzymes. Virtually all of these proteins are secreted via the general secretion (Sec) pathway. Studies from different laboratories have demonstrated essential or non-e...
journal_title:Microbial cell factories
pub_type: 杂志文章
doi:10.1186/s12934-020-01315-2
更新日期:2020-02-28 00:00:00
abstract:BACKGROUND:High-throughput methods are widely-used for strain screening effectively resulting in binary information regarding high or low productivity. Nevertheless achieving quantitative and scalable parameters for fast bioprocess development is much more challenging, especially for heterologous protein production. He...
journal_title:Microbial cell factories
pub_type: 杂志文章
doi:10.1186/1475-2859-11-144
更新日期:2012-10-31 00:00:00
abstract:BACKGROUND:L-tryptophan is an aromatic amino acid widely used in the food, chemical and pharmaceutical industries. In Escherichia coli, L-tryptophan is synthesized from phosphoenolpyruvate and erythrose 4-phosphate by enzymes in the shikimate pathway and L-tryptophan branch pathway, while L-serine and phosphoribosylpyr...
journal_title:Microbial cell factories
pub_type: 杂志文章
doi:10.1186/1475-2859-11-30
更新日期:2012-03-02 00:00:00
abstract:BACKGROUND:The thermostable serine protease pernisine originates from the hyperthermophilic Archaeaon Aeropyrum pernix and has valuable industrial applications. Due to its properties, A. pernix cannot be cultivated in standard industrial fermentation facilities. Furthermore, pernisine is a demanding target for heterolo...
journal_title:Microbial cell factories
pub_type: 杂志文章
doi:10.1186/s12934-019-1245-3
更新日期:2019-11-07 00:00:00