• Korean Journal of Plant Tissue Culture
• /
• v.27 no.4
• /
• pp.283-297
• /
• 2000

Seeds are an ideal repository for recombinant proteins in molecular farming applications. However, in order to use plant seeds efficiently for the production of such proteins, it is necessary to understand a number of fundamental biological properties of seeds. This includes a full understanding of promoters which function in a seed-specific manner, the subcellular targeting of the desired polypeptide and the final form in which a protein is stored. Once a biologically active protein has been deposited in a seed, it is also critical that the protein can be extracted and purified efficiently. In this review, these issues are examined critically to provide a number of approaches which may be adopted for production of recombinant proteins in plants. Particular attention is paid to the relationship between subcellular localization and protein extraction and purification. The robustness and flexibility of seed-based production is illustrated by examples close to or already in commercial production.

• Korean Journal of Microbiology
• /
• v.24 no.2
• /
• pp.119-126
• /
• 1986

A periplasmic endoprotease, named protease Pi, was purified to homogeneity from Escherkchia coli by conventional procedure with insulin as substrate. This enzyme degrades insulin and glucagon to trichloroacetic acid-soluble meterials, but shows little or no hydrolysis of bovine serum albumin, casein or globin. Its molecular weight was 110, 000 when determined by gel filtration on Sephacryl S-300 and was 105, 000 when estimated by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate. Thus, it appears to be single polypeptide. This snzyme is metalloprotease, since it is completely inhibited by o-phenanthroline and can be activated by addition of divalent metal cations, such as $Mg^{2+}\;and\;Co^{2+}$. It is destinct from protease Ci, a cytoplasmic insulin degrading enzyme, since protease Pi is localized to the periplasm. Since protease Pi selectively degrades GTP cyclohydrolase I, it appears to play a role in the regulation of pteridine biosynthesis.

• Journal of Plant Biology
• /
• v.37 no.2
• /
• pp.167-173
• /
• 1994

Poly(A)+ RNA was selected from Canavalia lineata root nodule RNA through oligo(dT) cellulose column and used for construction of a cDNA library using λgt10-EcoRI arms. The size of the library was 7.2$\times$105 pfu/mL. A full length leghemoglobin (Lb) cDNA clone, pCILb1(687 bp) isolated with soybean Lb probe, contained one open reading frame (ORF) of 447 bp with 54 bp plus 186 bp at 5' and 3' untranslated region, respectively. A consensus sequence of plant translation start region (AAAATGGG) was found at 5' untranslated region, and two polyadenylation-related sequence (AATAAA, AATAAG) and a conserved motif between them (gACTTGTT) were found upstream of poly(A)+ tail consisted of 13 (A)s at 3' untranslated region. The ORF encoded a polypeptide consisted of 149 amino acids with a molecular weight of 16.2 kD. Deduced amino acid sequences showed high degree of homology values with those of other Lbs ranging from 66% (Casuarina glauca) to 85% (Glycine max).

• BMB Reports
• /
• v.33 no.2
• /
• pp.133-137
• /
• 2000

To elucidate the effect of oxygen radicals on the molecular properties of proteins, the secondary and tertiary structure and molecular weight size of BSA and ${\beta}$-lactoglobulin were examined after irradiation of proteins at various doses. Gamma-irradiation of protein solutions caused the disruption of the ordered structure of protein molecules as well as degradation, cross-linking, and aggregation of the polypeptide chains. As a model system, BSA and ${\beta}$-lactoglobulin were used as a typical ${\alpha}$-helical and a ${\beta}$-sheet structure protein, respectively. A circular dichroism study showed that the increase of radiation decreased the ordered structure of proteins with a concurrent increase of aperiodic structure content. Fluorescence spectroscopy indicated that irradiation quenched the emission intensity excited at 280 nm. SDS-PAGE and a gel permeation chromatography study indicated that radiation caused initial fragmentation of proteins resulting in a subsequent aggregation due to cross-linking of protein molecules.

• Journal of Sericultural and Entomological Science
• /
• v.36 no.2
• /
• pp.119-123
• /
• 1994

By in vivo labelling of AMHP using[35S]-methionine, fat body culture and immunological analysis, it is proved that Bombyx adult fat body synthesizes 18K and 20K subunits of AMHP and releases them into haemolymph. Also these peptides are assembled to form native AMHP in the adult haemolymph.

• Korean Journal of Clinical Pharmacy
• /
• v.21 no.2
• /
• pp.57-65
• /
• 2011

Incretin hormones such as glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide delay gastric emptying, increasing satiety, and enhance insulin secretion. Two new classes of treatments related to incretin hormones for the management of type 2 diabetes mellitus have emerged: GLP-1 receptor agonists (e.g., exenatide, liraglutide) and the dipeptidyl peptidase-4 (DPP-4) inhibitors (e.g., sitagliptin, saxagliptin, vildagliptin, alogliptin), which prevent the degradation of GLP-1. A MEDLINE search was conducted in order to evaluate the efficacy and safety of incretin-based therapies and publications were reviewed. Data from clinical trials indicated incretin-based treatment showed clinically significant reductions in hemoglobin A1c with low risk of hypoglycemia. Weight reductions were observed with GLP-1 receptor agonists where as DPP-4 inhibitors are weight neutral.

• BMB Reports
• /
• v.32 no.5
• /
• pp.502-505
• /
• 1999

cDNA fragments of ovine liver pyridoxal kinase were amplified by PCR using degenerate oligonucleotide primers derived from partial amino acids sequences of the enzyme. Using PCR products as probes, several overlapping cDNA clones were isolated independently from an ovine liver and a human brain cDNA library. The largest cDNA clone for each was selected for sequence analysis. The ovine liver cDNA encodes a polypeptide of 297 amino acid residues with Mr of 32,925, whereas the human clone is comprised of an open reading frame encoding 312 amino acid residues with Mr of 35,102. The deduced sequence of the human brain enzyme is completely identical to that of human testes cDNA recently reported (Hanna et al., 1997). The ovine enzymes have approximately 77% sequence identity with the human enzyme although the two sequences are completely different in the N-terminus comprising 32 residues. This result suggests that pyridoxal kinase is highly homologous in mammalian species.

• Textile Coloration and Finishing
• /
• v.21 no.5
• /
• pp.1-9
• /
• 2009

The feasibility of earthworm protease as a new cosmetic material for human hair care was investigated. The effectiveness of the earthworm protease treatment was assessed by thickness change of hairs, optical microscope examination, aminoacid analysis, surface morphology, angular resolution analysis through methylene blue staining method and tensile strength change. The protease treated hair became thinner and the soil on the surface removed in experimental groups unlike control group. Tensile strength decreased in experimental group in which the enzymes may decompose polypeptide bonds.

• Microbiology and Biotechnology Letters
• /
• v.28 no.1
• /
• pp.21-25
• /
• 2000

We have got several clones from Serratia marcescens which stimulated the cells to use maltose as a carbon source in Escherichia. coli TP2139 ( lac, crp). One of the cloned genes, pCKB17, was further analyzed. In order to find whether the increased expression of the gent was under the direction of maltose metabolism, we constructed several recombinant subclones. We have found that the clone, pCKB17AV, codes maltose metabolism stimulation(mms) gene. E. coli transformed with the cloned gene showed increase in the activity of maltose utilzation, The recombinant proteins expressed by multicopy and induction with IPTG, one polypeptide of 29-kDa, was confirmed by SDS-PAGE. The overexpression of maltose-binding proter protein in the presence of mms gene was confirmed by Western blot analysis. Southern hybridization analysis confirmed that the cloned DNA fragment was originated from S. marcescens chromosomal DNA.

• Journal of Microbiology and Biotechnology
• /
• v.17 no.10
• /
• pp.1688-1694
• /
• 2007

A gene encoding the mannanase of Bacillus subtilis WL-3, which had been isolated from Korean soybean paste, was cloned into Escherichia coli and the nucleotide sequence of a 2.7-kb DNA fragment containing the mannanase gene was subsequently determined. The mannanase gene, designated manA, consisted of 1,080 nucleotides encoding a polypeptide of 360 amino acid residues. The deduced amino acid sequence was highly homologous to those of mannanases belonging to glycosyl hydrolase family 26. The manA gene was strongly expressed in B. subtilis 168 by cloning the gene downstream of a strong B. subtilis promoter of plasmid $pJ27{\Delta}88U$. In flask cultures, the production of mannanase by recombinant B. subtilis 168 reached maximum levels of 300 units/ml and 450 units/ml in LB medium and LB medium containing 0.3% locust bean gum, respectively. Based on the zymogram ofthe mannanase, it was found that the mannanase produced by recombinant B. subtilis could be maintained stably without proteolytic degradation during the culture time.