• Journal of Microbiology and Biotechnology
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• v.29 no.5
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• pp.667-686
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• 2019

Streptomyces are attractive microbial cell factories that have industrial capability to produce a wide array of bioactive secondary metabolites. However, the genetic potential of the Streptomyces species has not been fully utilized because most of their secondary metabolite biosynthetic gene clusters (SM-BGCs) are silent under laboratory culture conditions. In an effort to activate SM-BGCs encoded in Streptomyces genomes, synthetic biology has emerged as a robust strategy to understand, design, and engineer the biosynthetic capability of Streptomyces secondary metabolites. In this regard, diverse synthetic biology tools have been developed for Streptomyces species with technical advances in DNA synthesis, sequencing, and editing. Here, we review recent progress in the development of synthetic biology tools for the production of novel secondary metabolites in Streptomyces, including genomic elements and genome engineering tools for Streptomyces, the heterologous gene expression strategy of designed biosynthetic gene clusters in the Streptomyces chassis strain, and future directions to expand diversity of novel secondary metabolites.

• BMB Reports
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• v.30 no.3
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• pp.200-204
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• 1997

We eliminated introns from replication independent chicken H3.3 histone gene using a H3.3 cDNA clone and a genomic H3.3 clone. After introduction into Rat 3 cells, we observed its pattern of expression by analyzing mRNA from different phases of the cell cycle. Even without introns, the H3.3 gene was expressed constitutively at a low level throughout the cell cycle. This indicates that the introns in the H3.3 gene are not responsible for the cell cycle-independent expression of the gene. This result contradicts previous reports that suggested their importance in cell cycle regulated expression. We believe that other regions of the gene, promoter, coding region, and/or 3'-end of the gene, are involved in its expression pattern.

• Journal of Pharmaceutical Investigation
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• v.32 no.3
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• pp.153-159
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• 2002

Gene therapy is fundamentally a sophisticated drug delivery technology to cure a disease by the transfer of genetic material to modify living cells. In other words, the gene is used as a therapeutic drug much like a chemical compound is employed in chemotherapy. Currently almost 600 clinical trials are underway worldwide since the first clinical trials carried out in 1990 to treat adenosine deaminase deficiency using retroviral vectors. Despite the great progress still is there no gene therapy product being approved as a new drug. This is partly due to a lack of an ideal gene delivery system that is safe and can provide stable, optimal level production of the therapeutic proteins in the cell. This review covers the current status of several different biological and physico-chemical agents that are being developed as gene delivery vehicles. Although gene therapy promises great hopes toward the cure of a broad spectrum of genetic and acquired diseases, the success of gene therapy heavily asks for the development of vector systems for safe and efficient application in humans.

• Journal of Microbiology and Biotechnology
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• v.17 no.10
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• pp.1675-1681
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• 2007

The pseudodisaccharide salbostatin, which consists of valienamine linked to 2-amino-1,5-anhydro-2-deoxyglucitol, is a strong trehalase inhibitor. From our Streptomyces albus ATCC 21838 genomic library, we identified thirty-two ORFs in a 37-kb gene cluster. Twenty-one genes are supposed to be a complete set of modules responsible for the salbostatin biosynthesis. Through sequence analysis of the gene cluster, some of the upstream gene products (SalB, SalC, SalD, SalE, and SalF) revealed functional resemblance with trehalose biosynthetic enzymes. On the basis of this rationale, we isolated the five genes (salB, salC, salD, salE, and salF) from the S. albus ATCC 21838 and cloned them into the expression vector pWHM3. We demonstrated the noticeable expression and accumulation of trehalose, using only the five upstream biosynthetic gene cluster of salbostatin, in the transformed Streptomyces lividans TK24. Finally, 490 mg/l trehalose was produced by fermentation of the transformant with sucrosedepleted R2YE media.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.6
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• pp.827-831
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• 2007

Myostatin is a member of the transforming growth factor-${\beta}$(TGF-${\beta}$ super-family. It acts as a negative regulator for skeletal muscle growth. Myostatin mutations are characterized by a visible, generalized increase in muscle mass in double muscled cattle breeds. To understand the biochemistry and physiology of the Chinese Yellow bovine myostatin gene, we report here for the first time expression of the gene in Escherichia coli (E. coli). Primers of the myostatin gene of Chinese Yellow Cattle were designed on the basis of the reported bovine myostatin mRNA sequence (Gen-Bank Accession No. NM005259) and optimized for E. coli codon usage. XhoI and EcoRI restriction enzyme sites were incorporated in the primers, and then cloning vector and expression vector were constructed in a different host bacterium. The expressed protein had a molecule mass of about 16 kDa as determined by SDS-PAGE under reducing conditions. The expressed protein reacted specifically with myostatin monoclonal antibody on immunoblots. Our studies should lead to the investigation of the differences in myostatin genes of various cattle and could benefit human health and food animal agriculture.

• International Journal of Industrial Entomology and Biomaterials
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• v.7 no.2
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• pp.155-159
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• 2003

We describe here the complete nucleotide sequence and the exon-intron structure of the luciferase gene of the firefly, Lampyris noctiluca. The luciferase gene of the L. noctiluca firefly consisted of six introns and seven exons coding for 547 amino acid residues. From the translational start site to the end of last exon, the genomic DNA length of the L. noctiluca luciferase gene spans 1,976 bp.

• Macromolecular Research
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• v.14 no.3
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• pp.348-353
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• 2006

For enhancing the gene delivery efficiency of polyplexes, a new formulation was developed using PEI conjugated Pluronic F127 copolymer as an effective additive. Low molecular weight, branched polyethylenimine Mw 600 (LMW BPEI 600) was conjugated to the terminal end of Pluronic F127. The PEI-modified Pluronic copolymers formed a micellar structure in aqueous solution, similar to that of unmodified Pluronic copolymer. PEI modification of Pluronic copolymer increased the size of micelles while concomitantly raising the critical micelle concentration (CMC). The PEI-modified Pluronic copolymer was used as a micellar additive to enhance the gene transfection efficiency of pre-formulated polyelectrolyte complex nanoparticles composed of luciferase plasmid DNA and branched PEI Mw 25k (BPEI 25k) or polylysine Mw 39k (PLL 39k). The luciferase gene expression levels were significantly enhanced by the addition of the BPEI-modified Pluronic copolymer for the two formulations of BPEl and PLL polyplexes. The results indicated that the BPEI-modified Pluronic copolymer micelles ionically interacted on the surface of DNA/BPEI (PLL) polyplexes which might facilitate cellular uptake process.

• Journal of Pharmaceutical Investigation
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• v.30 no.1
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• pp.1-12
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• 2000

Gene therapy is a method for the treatment of diseases with introducing the gene-engineered materials into a patient with gene-deficiency disease (e.g. cystic fibrosis) or cancer to produce a therapeutic protein in a patient's cells. Successful gene therapy requires establishing both gene expression systems and delivery systems. Viral and non-viral vectors have been used for gene delivery. Viral vectors have a high transfection efficiency, but are limited in relations to issues of safety, toxicity and immunogenecity. Non-viral vectors are easy to prepare and relatively safe. However, non-viral vectors have a low transfection efficiency. Cationic liposomes are the most available among non-viral vectors. Cationic liposomes have been used to transfect cells both in vitro and in vivo experiments. Besides, several formulations containing cationic lipid are being used in clinical trials in cases of cystic fibrosis or cancer. A crucial subject to the further development of gene delivery vectors will be a long-term gene expression with following characteristics; protecting and deliverying DNA efficiently, non-toxic and non-immunogenic, and easy to produce in large scale.

• Journal of Microbiology and Biotechnology
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• v.11 no.3
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• pp.534-538
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• 2001

The xynA gene encoding an alikali-tolerant endo-1,4-${\beta}$-xylanase (XYN) was cloned from the alkalophilic Bacillus pumilus A-30. The nucleotide sequence of a 974-bp DNA fragment containing the xynA was determined. An ORF of 684 nucleotides that encoded a protein of 228 amino aicds was detected. Asparagine-71 of XYN from B. Pumilus A-30 showed to be highly conservative in alkaline xylanases of family G/11, upon comparing the amino acid sequences of 17 family G/11 xylanases. Site-directed mutation of N71D of the xynA gene resulted in a decrease of 12.4% in the specific acitivity and a significant decline in the enzyme activity in the alkaline pH range.

• Journal of fish pathology
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• v.35 no.1
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• pp.103-111
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• 2022

This study has been performed to investigate the potential effects of by-product discarded after probiotics production (BPPP) on growth performance, immune gene expression, innate-immunity status, and disease resistance of carp, Cyprinus carpio. For 3 weeks, carp were fed four diets containing different levels of BPPP at 0, 0.1, 0.2 and 0.5% per kg of normal diet. Every 7 days of feeding, immune-related gene expression, serum lysozyme activity and ACH₅₀ were analyzed. Growth rates and challenge test with E. tarda were conducted after 3 weeks of BPPP feeding. Both lysozyme activity and ACH₅₀ were significantly (p<0.05) increased in all BPPP supplemented groups compared to the control at every 7 day for 3 weeks of feeding trial. The gene expression of pro-inflammatory cytokines, IL-1β and TNF-α was significantly (p<0.05) up-regulated until 21 days of feeding in all groups except for 0.2% group on day 7 post feeding. The anti-inflammatory cytokine IL-10 gene expression was only significantly (p<0.05) increased in 0.1% group on day 7 and decreased (p<0.05) on day 14 in all BPPP supplemented groups. On day 21, the IL-10 gene expression was augmented (p<0.05) in all groups. SOD gene expression was significantly (p<0.05) increased compared to the control on day 14 and 21 post feeding, whereas no significant difference was observed on day 7. In challenging test, 0.2%, 0.1%, 0.5% and control group showed 80%, 70%, 60% and 40% of survival rate, respectively. Feed conversion rate was only improved in 0.5% group. In conclusion, the present study indicates that dietary BPPP suplementation improved growth performance, innate immune response and bactericidal activity in carp.