Clostridium perfringens (C. perfringens) induced necrotic enteritis (NE) and related subclinical disease has become economically significant problems for the broiler industry. The objectives of this study were to determine the toxinotype and the antimicrobial susceptibility of C. perfringens isolated from the intestine of NE-suspicious and clinically healthy chickens in Korea. All of the 110 isolates belong to C. perfringens type A. In addition, these strains harbored the luxS, colA, virS, cpb2, netB and tpeL genes in high percentage order. They do not harbor the cpe gene encoding enterotoxin production. Our results suggest the important roles of the several toxin genes in the pathogenesis of NE except α-toxin, previously thought to be the major virulence factor. In the antimicrobial susceptibility test of 13 antimicrobial agents, none of them is completely susceptible in this study. Remarkably NE-suspicious chickens have higher resistant value than health ones in all of antimicrobial agents. The presence of tetracycline-resistance genes were also tested to analyze the correlation of genotype and phenotype.

Toll-like receptor 7 (TLR7) is critical for the triggering of innate immune response by recognizing the conserved molecular patterns of single-stranded RNA (ssRNA) viruses and mediated antigenic adaptive immunity. To understand how TLR7 distinguish pathogen-derived molecular patterns from the host self, it is essential to be able to identify TLR7 receptor interaction interfaces, such as active sites or R848-agonist binding sites. The functional interfaces of TLR7 can serve as targets for structure-based drug design in studying the TLR7 receptor’s structure-function relationship. In contrast to mammalian TLR7, chicken TLR7 (chTLR7) is unknown for its important biological function. Therefore, it has been targeted to mediate contrasting evolutionary patterns of positive selection into non-synonymous SNPs across eleven species using TLR7 conservation patterns (evolutionary conserved and class-specific trace residues), where protein sequence differences to the TLR7 receptors of interest record mutation that have passed positive section across the species. In this study, we characterized the Lys609 residue on chTLR7-ECD homodimer interfaces to reflect the current tendency of evolving positive selection to be transfer into a stabilization direction of the R848-agonist/ chTLR7-ECDs complex under the phylogenetically variable position across species and we suggest a potential indicator for contrasting evolutionary patterns of both the species TLR-ECDs.

본 연구에서는 탄화수소계열 고분자인 sulfonated poly arylene ether sulfone(SPAES) 고분자를 이용하여 연료전지용 전해질막을 제조하였으며 메탄올 투과도를 최적화 하기 위하여 소수성 고분자인 polyethersulfone(PES), Polyvinylidene fluoride (PVdF) 를 소량 첨가하여 블렌드막을 제조하였다. 제조된 분리막은 연료전지용 전해질 막으로써 요구되는 물리적, 화학적 안정성, 이온전도도, 셀 테스트등의 기본 물성을 측정하여 잠재적인 적용 가능성을 테스트 해보았다 또한 분자동력학 시뮬레이션을 이용하여 소수성 고분자와 SPAES고분자의 혼화성 측정과, 이온 및 메탄올 분자의 투과도를 예측해 보았으며 이를 이용하여 실제 실험 결과와 비교 분석을 진행하였다.

최근 국내 포도원에서 과실 표면에 구름모양의 흰색 얼룩이 자주 발견되고 있으나, 그 원인에 대해 명확히 알려진 바가 없어 방제대책을 세우지 못하고 있는 실정이다. 흰색의 달무리 반점은 포도 과실 표면에 부정형으로 퍼져 있으며, 그 중앙에는 총채벌레가 산란할 때 만들어진 작은 구멍의 상처가 남아 있다. 이 상처부위는 시간이 지나면서 코르크화되고 표피세포와 분리되어 딱지로 남거나 떨어져 나가게 된다. 이러한 증상은 총채벌레의 섭식이나 노린재의 흡즙에 의한 상처와는 구별된다. 산란구멍에서 발견한 총채벌레 알껍질에서 DNA를 추출하여 ITS2 부위의 염기 서열을 PCR-RFLP 방법으로 분자동정을 실시한 결과 꽃노랑총채벌레의 것으로 확인되었다. 미토콘드리아 COI 염기서열은 이러한 분자 동정 결과를 재확인하여 주었다. 본 연구결과는 포도 과피에 꽃노랑총채벌레 산란에 의해 유발되는 독특한 피해 증상에 대한 정확한 정보를 제공하며 포도원에서 이 해충에 대한 방제전략 수립에 도움이 될 것으로 여겨진다.

A full-length lysozyme cDNA from Gryllotalpa orientalis was cloned and sequenced. The deduced amino acid sequence of the lysozyme protein was 143 amino acids in length, with a calculated molecular mass of 15.84 kDa and an isoelectric point of 4.74. Sequence motifs, together with alignment and phylogenetic results, confirmed that G. orientalis lysozyme belongs to the C (chicken)-type lysozyme family of proteins. The protein sequence of lysozyme from G. orientalis showed high identity to that of Drosophila melanogaster (51.7%); however, in contrast to D. melanogaster lysozyme, G. orientalis lysozyme was immune inducible and expressed in a wide range of tissues. Expression of G. orientalis lysozyme mRNA was highest at 8 h post-infection and subsequently decreased with time after bacterial infection. We also expressed G. orientalis lysozyme protein in vitro using the pET expression system. Compared with the negative control, over-expressed G. orientalis lysozyme showed antimicrobial activity against Gram-negative bacteria Escherichia coli and Gram-positive bacteria Bacillus subtilis by radial diffusion assay, with MIC values of 30.3 μM and 7.55 μM respectively. These results indicate that G. orientalis lysozyme may have stronger antimicrobial activity than other lysozymes against a broad range of microorganisms.

In 2008, leaf blight symptoms were observed on several Chinese chive farms in Sangju. The Pathogenicity of the isolate was confirmed by artificial inoculation, where the pathogen exhibited a strong pathogenicity toward healthy plants. Morphological classification identified the isolate as from the Fusarium genus. For further analysis, PCR and phylogenetic classification were performed with ITS region and 28S rRNA gene which are commonly used for fungal identification. However, the results provided a poor resolution. To solve this problem, we analyzed translation elongation factor 1-alpha (TEF-1α) gene. The analyzed results using TEF-1α gene indicated that the isolate was F. proliferatum. Therefore, it is assumed that TEF-1α gene is important when Fusarium sp. was identified using molecular classification method.

Rotaviruses are double-stranded RNA viruses of the family Reoviridae, a highly diverse family of pathogens of humans and animals. In this study, we identified the lapine rotavirus from diarrheic feces of rabbits by polymerase chain reaction. In order to determine the genetic characteristics of the Korean strain, the sequences of the VP4, VP7, and NSP4 genes were determined and compared with those of reference sequences. Results of sequence and phylogenetic analyses showed that our strain was a G3P [3] rotavirus carrying the group C gene encoding NSP 4 proteins. This is the first report of an outbreak and molecular characterization of lapine rotavirus in Korea.

CD63, a member of tetraspanin membrane protein family, plays pivotal role in cell growth, motility, signal transduction, host-pathogen interactions and cancer. In this work, the cDNA encoding CD63 homologue (TmCD63) was cloned from larvae of coleopteran beetle, Tenebrio molitor. The cDNA is comprised of an open reading frame of 705 bp, encoding putative protein of 235 amino acid residues. In silico analysis shows that the protein has four putative transmembrane domains and one large extracellular loop. The characteristic ‘Cys-Cys-Gly’ motif and ‘Cys188’ residues are highly conserved in the large extracellular loop. Phylogenetic analysis of TmCD63 revealed that they belong to the insect cluster with 50-56% identity. Analysis of spatial expression patterns demonstrated that TmCD63 mRNA is mainly expressed in gut and Malphigian tubules of larvae and the testis of the adult. Developmental expression patterns of CD63 mRNA showed that TmCD63 transcripts are detected in late larval, pupal and adult stages. Interestingly, TmCD63 transcript was upregulated the maximum 4.5 fold in response to DAP-type peptidoglycan during the first 6 h, although other immune elicitors also made significant increase in the transcript level at later time-points. These results suggest that CD63 might contribute to T. molitor immune response against various microbial pathogens.

The novel serogroup of Bacillus thuringiensis serovar mogi (H3a3b3d) was isolated from fallen leaves, sampled in a forest region of the city of Mungyeong, Korea. Plasmids from B. thuringiensis have been implicated in pathogenicity as they carry the genes responsible for different types of diseases in mammals and insects. In this study, the genome sequence of the strain was determined. The 6.0-Mb genome of B. thuringiensis mogi contains three replicons: a circular chromosome (5.40-Mb) encoding 5,652 predicted open reading frames (ORFs), and two megaplasmids, pMOGI364 (364 564 bp) and pMOGI222 (222 348 bp). The G+C contents of these replicons ranged from 31.3% to 34.2% for pMOGI364 and pMOGI222, respectively. There are six putative cry genes, cry19Bb1, cry73Aa, cry20Bb1, cry27Ab1, cry4Aa and cry56Ba1, distributed on these two megaplasmids. To investigate the role of these genes in crystal production, the expression profiles of these toxin genes were analyzed by quantitative PCR (qPCR) from the wild type strain. Also, these cry genes were cloned to the Escherichia coli-B. thuringiensis shuttle vector, pHT1K under the control of its own promoter and then introduced into an acrystalliferous B. thuringiensis Cry-B strain for further molecular characterization.