• Korean Journal of Microbiology
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• v.45 no.2
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• pp.228-231
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• 2009

We have purified Phytophthora capsici alpha and beta tubulin from Escherchia coli BL21(DE3). The recombinant alpha and beta tubulins were assembled into microtubule in vitro with specific conditions. The metagenome library was isolated from soil in the Mt. Yeo-Ki, Suwon, Korea and manufactured with the method mentioned in experiment contents for in vitro screening of microtubule assembly screening. FRET effect was used for microtubule assembly inhibitor screening with metagenome library. We got 2 metagenome clones from in vitro screening, and these 2 hit clones showed P. capsici growth inhibition activity on the growing pepper plants. These results suggest that new development of potent inhibitor for pepper blight disease and new approach to prevention of pepper blight disease.

• Korean Chemical Engineering Research
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• v.52 no.1
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• pp.45-51
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• 2014

This is to study the effects of various pretreatment methods of agricultural residue, corn stover, and to compare the feature and pros and cons of each method including dilute sulfuric acid (DSA), soaking in aqueous ammonia (SAA), and ammonia recycle percolation (ARP). In order to convert corn stover to ethanol, various pretreatments followed by simultaneous saccharification and co-fermentation (SSCF) were tested and evaluated in terms of ethanol yield. With 3%, w/w of glucan loading using ARP-, DSA-, and SAA-treated solids, SSCFs using recombinant E. coli strain (ATCC$^{(R)}$ 55124) with commercial enzymes (15 FPU of Spezyme CP/g-glucan and 30 CBU/g-glucan enzyme loading) were tested. In the SSCF tests, 87, 90, and 78% of theoretical maximum ethanol yield were observed using ARP-, DSA-, and SAA-treated solids, respectively, which were 69, 58, and 74% on the basis of total carbohydrates (glucan + xylan) in the untreated corn stover. Ethanol yield of SAA-treated solid was higher than those of ARP- and DSA-treated solids. In addition, SSCF test using treated solids plus pretreated hydrolysate indicated that the DSA-treated hydrolysate showed the strongest inhibition effect on the KO11 strain, whereas the ARP-treated hydrolysate was found to have the second strongest inhibition effect. Bioconversion scheme using SAA pretreatment and SSCF can make the downstream process simple, which is suggested to produce ethanol economically because utilization of hemicellulose in the hydrolysate is not necessary.

• Journal of Life Science
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• v.19 no.7
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• pp.845-851
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• 2009

A vector harboring double cassettes; a heterologous gene expression cassette of pHCE-InaN-antigen and a ghost formation cassette of pAPR-cI-E lysis 37 SDM was constructed and introduced to E. coli DH5a. For the production of a bacterial ghost vaccine, bacterial ghosts from E. coli / Streptococcus iniae with four different types of antigens - enolase, GAPDH, sagA and piaA - were produced by the optimization of fermentation parameters such as a glucose concentration of 1 g/l, agitation of 300 rpm and aeration of 1 vvm. Efficiency of ghost bacteria formation was evaluated with cultures of OD$_{600}$=1.0, 2.0 and 3.0. The efficiency of the ghost bacteria formation was 99.54, 99.67, 99.99 and 99.99% with inductions at OD$_{600}$=3.0, 1.0, 2.0 and 1.0 for E. coli/S. iniae antigens enolase, piaA, GAPDH and sagA, respectively. Ghost bacteria as a vaccine was harvested by centrifugation. The antigen protein expressions were analyzed by SDS-PAGE and western blot analysis, and the molecular weights of the enolase, piaA, GAPDH and sagA were 78, 26, 67 and 26 kDa, respectively. The molecular weights of the expressed antigens were consistent with theoretical sizes obtained from the amino acid sequences.