Publications by authors named "Qurratulann Afza Gardner"

Surface layer (S-layer) is an extracellular proteinous layer consisting of two-dimensional lattice. It is typically present on archaea and also found on some bacteria. S-layer proteins from some bacteria are reported to be toxic to mosquito larvae.

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Serum amyloid A1 (SAA1) is an apolipoprotein which is involved in amyloid A amyloidosis (AA) by forming fibrils. The process of fibrillation is still being explored and holds challenges in recombinant expression and purification of SAA1. This study deals with the preferable approach for the expression and purification of SAA1 which is normally toxic and unstable to express without using any fusion-tag.

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Alpha amylases catalyse the hydrolysis of α-1, 4-glycosidic bonds in starch, yielding glucose, maltose, dextrin, and short oligosaccharides, vital to various industrial processes. Structural and functional insights on α-amylase from Methanocaldococcus jannaschii were computationally explored to evaluate a catalytic domain and its fusion with a small ubiquitin-like modifier (SUMO). The recombinant proteins' production, characterization, ligand binding studies, and structural analysis of the cloned amylase native full gene (MjAFG), catalytic domain (MjAD) and fusion enzymes (S-MjAD) were thoroughly analysed in this comparative study.

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Antimicrobial resistance is a major challenge in the field and threat to human life. Many patients are suffering from cancer, infection and other diseases simultaneously. Therefore, early detection of infection can lead to treatment of these patients with an appropriate antibiotic.

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Ovarian cancer (OC) is the most lethal among female reproductive system malignancies. Depending upon the stage at presentation, the five year survival ratio varies from ∼92 to ∼30%. The role of biomarkers in early cancer diagnosis, including OC, is well understood.

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Obesity is marked by the buildup of fat in adipose tissue that increases body weight and the risk of many associated health problems, including diabetes and cardiovascular disease. Treatment options for obesity are limited, and available medications have many side effects. Thus there is a great need to find alternative medicines for treating obesity.

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Enrichment of glycoproteins has been important because of their dynamicity and role in biological systems. Study of glycoproteins is complex because of the simultaneous glycosylation and deglycosylation inside the body. Often employed affinities for glycopeptides are hydrazide, boronic acid, or physiosorbed lectin on support materials.

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Purpose: An early and accurate diagnosis of ovarian carcinoma (OC) may reduce morbidity and mortality of the patients. To improve the clinical outcome in OC patients, the present study is aimed at identifying robust biomarkers for early OC diagnosis. EXPERIMENTAL DESIGN: In order to look for early-stage protein markers, a systematic protein profiling approach involving 2-dimensional electrophoresis coupled with mass spectrometric analyses of human malignant and non-malignant ovarian biopsy samples, is performed.

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Porphobilinogen synthase (PBG synthase) gene from Pyrobaculum calidifontis was cloned and expressed in E. coli. The recombinant enzyme was purified as an octamer and was found by mass spectrometry to have a subunit M of 37676.

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The present study deals with mass spectrometric investigation to characterize the nature of proinsulin in inclusion bodies. Various derivatives of human proinsulin were cloned, expressed in E. coli and inclusion bodies prepared under weak acidic conditions (pH 6.

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In the present study, two common buthid scorpions, i.e., Androctonus finitimus (Pocock, 1897) (Scorpiones: Buthidae) and Hottentota tamulus (Fabricus, 1798) (Scorpiones: Buthidae), were maintained in the laboratory for venom recovery.

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We have previously shown that human interferon α-2b (IFN) produced in Escherichia coli (E. coli) is heterogeneous at the N-terminal, with three major species (Ahsan et al., 2014).

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Tk1884, an open reading frame encoding α-amylase in Thermococcus kodakarensis, was cloned with the native signal sequence and expressed in Escherichia coli. Heterologous gene expression resulted in secretion of the recombinant protein to the extracellular culture medium. Extracellular α-amylase activity gradually increased after induction.

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Eight proinsulin encoding genes were prepared and their translation products, when treated with a cocktail of trypsin and carboxypeptidase B, analyzed for the following features. One, their ability to undergo facile removal of the N-terminal linker, generating the phenylalanine residue destined to be the N-terminal of the B-chain of insulin, at a rate similar to that involved in the removal of the C-peptide. Two, processing of diarginyl insulin, produced in the latter process, by carboxypeptidase B then needed to be rapid to remove the two arginine residues, Three, both these operations were to be efficient whether the N-terminal methionine was acylated or not.

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Examples of N-terminal acetylation are rare in prokaryotic systems, but in this study, we report one such example in which N-terminal Cys residue of recombinant human interferon α-2b produced in Escherichia coli is a favourite site for N(α)-acetylation. The recombinant protein following Q-sepharose chromatography gave a single band on PAGE analysis. However, on reverse phase HPLC the material separated into three peaks.

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Seven nicotinamide adenine dinucleotide oxidase homologs have been found in the genome of Thermococcus kodakaraensis. The gene encoding one of them, TK1299, consisted of 1326 nucleotides, corresponding to a polypeptide of 442 amino acids. To examine the molecular properties of TK1299, the structural gene was cloned, expressed in Escherichia coli and the gene product was characterized.

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Human M-proinsulin was cleaved by trypsin at the R(31)R(32)-E(33) and K(64)R(65)-G(66) bonds (B/C and C/A junctions), showing the same cleavage specificity as exhibited by prohormone convertases 1 and 2 respectively. Buffalo/bovine M-proinsulin was also cleaved by trypsin at the K(59)R(60)-G(61) bond but at the B/C junction cleavage occurred at the R(31)R(32)-E(33) as well as the R(31)-R(32)E(33) bond. Thus, the human isoform in the native state, with a 31 residue connecting C-peptide, seems to have a unique structure around the B/C and C/A junctions and cleavage at these sites is predominantly governed by the structure of the proinsulin itself.

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Glycine oxidase gene from a strain of Bacillus subtilis was cloned and expressed in Escherichia coli. The purified enzyme was found, by mass spectrometry, to have a protein M(r) of 40763 (value of 40761.6 predicted from DNA sequence) and a FAD prosthetic group M(r) of 785.

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Secondary structure elements of human proinsulin and of its tryptic products were compared by H/D exchange, in a single-pot, using mass spectrometry. Human proinsulin containing an N-terminal methionine, M-proinsulin, was engineered and converted into a perdeuterio derivative, which using an optimized mass spectrometric protocol and manual calculations gave a mass of 9669.6 (+/-1) Da showing the replacement, with deuterium of 146.

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