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941.
942.
Kim D Kim SN Baik KS Park SC Lim CH Kim JO Shin TS Oh MJ Seong CN 《Journal of microbiology (Seoul, Korea)》2011,49(1):141-145
A metagenomic fosmid library was constructed using genomic DNA isolated from abalone intestine. Screening of a library of
3,840 clones revealed a 36 kb insert of a cellulase positive clone (pAMHElO). A shotgun clone library was constructed using
the positive clone (pAMHElO) and further screening of 3,840 shotgun clones with an approximately 5 kb insert size using a
Congo red overlay revealed only one cellulase positive clone (pAMHL9). The pAMHL9 consisted of a 5,293-bp DNA sequence and
three open reading frames (ORFs). Among the three ORFs, cellulase activity was only shown in the recombinant protein (CelAMll)
coded by ORF3, which showed 100% identity with outer membrane protein A from Vibrio alginolyticus 12G01, but no significant sequence homology to known cellulases. The expressed protein (CelAMll) has a molecular weight of
approximately 37 kDa and the highest CMC hydrolysis activity was observed at pH 7.0 and 37°C. The carboxymethyl cellulase
activity was determined by zymogram active staining and different degraded product profiles for CelAMll were obtained when
cellotetraose and cellopentaose were used as the substrates, while no substrate hydrolysis was observed on oligosaccharides
such as cellobiose and cellotriose. 相似文献
943.
Kim KK Kim YO Park S Kang SJ Nam BH Kim DN Oh TK Yoon JH 《Journal of microbiology (Seoul, Korea)》2011,49(3):381-386
A Gram-staining-negative, motile, non-spore-forming and rod-shaped bacterial strain, 20-23RT, was isolated from intestine of bensasi goatfish, Upeneus bensasi, and its taxonomic position was investigated by using a polyphasic study. Phylogenetic analyses based on 16S rRNA gene sequences
revealed that strain 20-23RT belonged to the genus Shewanella. Strain 20-23RT exhibited 16S rRNA gene sequence similarity values of 99.5, 99.2, and 97.5% to Shewanella algae ATCC 51192T, Shewanella haliotis DW01T, and Shewanella chilikensis JC5T, respectively. Strain 20-23RT exhibited 93.1–96.0% 16S rRNA gene sequence similarity to the other Shewanella species. It also exhibited 98.3–98.4% gyrB sequence similarity to the type strains of S. algae and S. haliotis. Strain 20-23RT contained simultaneously both menaquinones and ubiquinones; the predominant menaquinone was MK-7 and the predominant ubiquinones
were Q-8 and Q-7. The fatty acid profiles of strain 20–23RT, S. algae KCTC 22552T and S. haliotis KCTC 12896T were similar; major components were iso-C15:0, C16:0, C16:1 ω7c and/or iso-C15:0 2-OH and C17:1 ω8c. The DNA G+C content of strain 20-23RT was 53.9 mol%. Differential phenotypic properties and genetic distinctiveness of strain 20–23RT, together with the phylogenetic distinctiveness, revealed that this strain is distinguishable from recognized Shewanella species. On the basis of the data presented, strain 20-23RT represents a novel species of the genus Shewanella, for which the name Shewanella upenei sp. nov. is proposed. The type strain is 20–23RT (=KCTC 22806T =CCUG 58400T). 相似文献
944.
Kim MJ Kim CS Park JY Park SN Yoo SY Lee SY Kook JK 《Journal of microbiology (Seoul, Korea)》2011,49(1):165-168
In general, an antimicrobial test for screening anti-caries natural extracts was performed by measuring the minimum bactericidal
concentration (MBC) against the type strains of mutans streptococci. However, it is unclear if the antimicrobial efficiency
of natural extracts on the type strains of mutans streptococci is the same on the clinical strains. In this study, we introduced
a bacterial model system for the screening of anti-caries and determining the optimal concentration of them to develop oral
hygiene products for Korean populations. 相似文献
945.
Lee SW Won JY Lee HY Lee HJ Youn SW Lee JY Cho CH Cho HJ Oh S Chae IH Kim HS 《Molecular medicine (Cambridge, Mass.)》2011,17(9-10):1095-1106
Early reperfusion after myocardial ischemia that is essential for tissue salvage also causes myocardial and vascular injury. Cardioprotection during reperfusion therapy is an essential aspect of treating myocardial infarction. Angiopoietin-1 is an endothelial-specific angiogenic factor. The potential effects of angiopoietin-1 on cardiomyocytes and vascular cells undergoing reperfusion have not been investigated. We propose a protective mechanism whereby angiopoietin-1 increases the integrity of the endothelial lining and exerts a direct survival effect on cardiomyocytes under myocardial ischemia followed by reperfusion. First, we found that angiopoietin-1 prevents vascular leakage through regulating vascular endothelial (VE)-cadherin phosphorylation. The membrane expression of VE-cadherin was markedly decreased on hypoxia/reoxygenation but was restored by angiopoietin-1 treatment. Interestingly, these effects were mediated by the facilitated binding between SH2 domain-containing tyrosine phosphatase (SHP2) or receptor protein tyrosine phosphatase μ (PTPμ) and VE-cadherin, leading to dephosphorylation of VE-cadherin. siRNA against SHP2 or PTPμ abolished the effect of angiopoietin-1 on VE-cadherin dephosphorylation and thereby decreased levels of membrane-localized VE-cadherin. Second, we found that angiopoietin-1 prevented cardiomyocyte death, although cardiomyocytes lack the angiopoietin-1 receptor Tie2. Angiopoietin-1 increased cardiomyocyte survival through integrin-β1-mediated extracellular signal-regulated kinase (ERK) phosphorylation, which inhibited caspase-9 through phosphorylation at Thr12? and subsequently reduced active caspase-3. Neutralizing antibody against integrin-β1 blocked these protective effects. In a mouse myocardial ischemia/reperfusion model, angiopoietin-1 enhanced cardiac function and reduction in left ventricular-end systolic dimension (LV-ESD) and left ventricular-end diastolic dimension (LV-EDD) with an increase in ejection fraction (EF) and fractional shortening (FS). Our findings suggest the novel cardioprotective mechanisms of angiopoietin-1 that are achieved by reducing both vascular leakage and cardiomyocyte death after ischemia/reperfusion injury. 相似文献
946.
Here, we report the quantification of porcine endogenous retrovirus (PERV) copy numbers using real time PCR. After generating standard curves using plasmid DNA, copy numbers were determined for PERV pol and for a housekeeping gene, porcine estrogen receptor2 (ER2) with the same amount of genomic DNA. Using this method, we examined 6 pig breeds in Korea including two breeds of miniature pig, one domestic pig from Jeju, and imported pig breeds, Duroc, Landrace, and Yorkshire. All breeds showed PERV copy numbers ranging from 9 to 50. This method will be useful for monitoring of PERVs in a porcine xenograft. 相似文献
947.
Won-Jae Chi Eun A. Oh Jong-Hee Kim Soon-Kwang Hong 《Biotechnology and Bioprocess Engineering》2011,16(1):59-71
Production of proteins in secretary form is one of the important factors affecting fermentation. The Tat (twin arginine translocation)
protein secretion system, which includes the proteins TatA, TatB, and TatC, was identified in the genomic sequence of Streptomyces griseus IFO13350. The tatA and tatC genes were organized into a polycistronic operon, whereas tatB was located separately on the chromosome. Comparison of amino acid sequences suggested that TatC was a membrane-spanning
protein, whereas TatA and TatB were found to be cytoplasmic proteins. Analysis of extracellular proteins and N-terminal amino
acid sequencing revealed that secretion of SGR5556 was significantly enhanced by overexpression of TatAC in S. griseus HH1. Further, enzymatic study showed that SGR5556 encoded a glycerophosphoryl diester phosphodiesterase. In addition, other
hydrolase activities, such as those of amylase, total protease, metalloprotease, trypsin, chymotrypsin, and Leuaminopeptidase,
were also enhanced by 3, 3, 2.6, 2.3, 5.4, and 2.5 fold, respectively, in S. griseus upon TatAC overexpression. Overexpression of TatAC induced the production of a greenish-yellow pigment in S. griseus HH1 as well as more abundant sporulation at an earlier stage in Streptomyces coelicolor A3(2). In silico analysis by TatFIND, SignalP, and TMHMM identified 19 binding proteins, 28 enzymatic proteins, and 27 other proteins with
unknown functions as putative TatAC-dependent secretary proteins. These results clearly indicate that TatA and TatC constitute
a functional Tat system in S. griseus. Additionally, the S. griseus Tat system can be useful for the production of valuable proteins, including many hydrolytic enzymes and candidates of Tat-dependent
secretary proteins, under industrial conditions. 相似文献
948.
949.
Hawon Lee Dae Haeng Cho Yong Hwan Kim Soo-Jeong Shin Sung Bong Kim Sung Ok Han Jinwon Lee Seung Wook Kim Chulhwan Park 《Biotechnology and Bioprocess Engineering》2011,16(4):755-760
The hydrolysis which converts polysaccharides to the fermentable sugars for yeast’s lingocellulosic ethanol production also
generates byproducts which inhibit the ethanol production. To investigate the extent to which inhibitory compounds affect
yeast’s growth and ethanol production, fermentations by Saccharomyces cerevisiae K35 were investigated in various concentrations of acetic acid, furfural, 5-hydroxymethylfurfural (5-HMF), syringaldehyde,
and coumaric acid. Fermentation in hydrolysates from yellow poplar and waste wood was also studied. After 24 h, S. cerevisiae K35 produced close to theoretically predicted ethanol yields in all the concentrations of acetic acid tested (1 ∼ 10 g/L).
Both furans and phenolics inhibited cell growth and ethanol production. Ethanol yield, however, was unaffected, even at high
concentrations, except in the cases of 5 g/L of syringaldehyde and coumaric acid. Although hydrolysates contain various toxic
compounds, in their presence, S. Cerevisiae K35 consumed close to all the available glucose and yielded more ethanol than theoretically predicted. S. Cerevisiae K35 was demonstrated to have high tolerance to inhibitory compounds and not to need any detoxification for ethanol production
from hydrolysates. 相似文献
950.
Hyun Na Koo Sung Min Bae Jae Bang Choi Tae Young Shin Bit Na Rae Yun Jae Young Choi Kwang Sik Lee Jong Yul Roh Yeon Ho Je Byung Rae Jin Sung Sik Yoo Jae Su Kim Young In Kim In Joong Yoon Soo Dong Woo 《Journal of Asia》2011,14(1):107-117
To characterize the NYJ strain of pseudorabies virus (PRV; Alphaherpesvirus of swine) isolated from the serum of an infected swine in Korea, the nucleotide sequence of three major glycoproteins (gB, gC, and gD) was analyzed. The expression of most potent immunogenic glycoprotein (gD) was also investigated using a Bombyx mori nucleopolyhedrovirus (BmNPV) expression system. The length of the glycoprotein genes corresponding to gB, gC, and gD of the NYJ strain were 2751 bp, 1443 bp, and 1203, respectively, and their identity ranged from 94.2% to 99.8% when compared with other strains. Phylogenetic analyses using these sequences showed that the NYJ strain forms a distinct branch with high bootstrap support. A novel transfer vector (pBmKSK4) was engineered with the polyhedrin promoter of BmNPV and a 6xHis tag to express glycoprotein gD in Bm5 cells and silkworm, B. mori, larvae. The immunogenicity of recombinant gD was demonstrated by its specific detection in both Bm5 cells and silkworm larvae by porcine anti-PRV antibody. The results of this study have implications both for the taxonomy of Korean PRV strains and vaccine development. 相似文献