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11.
Background
Influenza B and C are single-stranded RNA viruses that cause yearly epidemics and infections. Knowledge of RNA secondary structure generated by influenza B and C will be helpful in further understanding the role of RNA structure in the progression of influenza infection.Findings
All available protein-coding sequences for influenza B and C were analyzed for regions with high potential for functional RNA secondary structure. On the basis of conserved RNA secondary structure with predicted high thermodynamic stability, putative structures were identified that contain splice sites in segment 8 of influenza B and segments 6 and 7 of influenza C. The sequence in segment 6 also contains three unused AUG start codon sites that are sequestered within a hairpin structure.Conclusions
When added to previous studies on influenza A, the results suggest that influenza splicing may share common structural strategies for regulation of splicing. In particular, influenza 3′ splice sites are predicted to form secondary structures that can switch conformation to regulate splicing. Thus, these RNA structures present attractive targets for therapeutics aimed at targeting one or the other conformation. 相似文献12.
S M Cha?kovskaia P S Braginskaia N P Tochenaia V M Grigor'eva N E Klimova 《Antibiotiki》1978,23(2):171-173
The efficiency of 3 variants of the method for determination of microbial flora was compared on the injection preparation of potassium benzylpenicillin artificially infected with Staph. aureus 209P and the spores of Bac. subtilis ATCC 6633 in different doses and with different amounts of the preparation in the vials. The procedure of the preparation dissolution in the vial with the thioglycol medium containing penicillinase proved to be most effective. The microbe detection amounted to 100 per cent. The procedure was less labour- and time-consuming since addition of penicillinase to each vial with the thioglycol medium was excluded. The risk of the medium occasional infection with microbial flora during the assay was decreased. 相似文献
13.
Hyung-Jun Kwon Young Bae Ryu Young-Min Kim Naaleum Song Cha Young Kim Mun-Chual Rho Jae-Ho Jeong Kyoung-Oh Cho Woo Song Lee Su-Jin Park 《Bioorganic & medicinal chemistry》2013,21(15):4706-4713
Despite the prepdominat agent causing severe entero-pathogenic diarrhea in swine, there are no effective therapeutical treatment of porcine epidemic diarrhea virus (PEDV). In this study, we evaluated the antiviral activity of five phlorotannins isolated from Ecklonia cava (E. cava) against PEDV. In vitro antiviral activity was tested using two different assay strategies: (1) blockage of the binding of virus to cells (simultaneous-treatment assay) and (2) inhibition of viral replication (post-treatment assay). In simultaneous-treatment assay, compounds 2–5 except compound 1 exhibited antiviral activities of a 50% inhibitory concentration (IC50) with the ranging from 10.8 ± 1.4 to 22.5 ± 2.2 μM against PEDV. Compounds 1–5 were completely blocked binding of viral spike protein to sialic acids at less than 36.6 μM concentrations by hemagglutination inhibition. Moreover, compounds 4 and 5 of five phlorotannins inhibited viral replication with IC50 values of 12.2 ± 2.8 and 14.6 ± 1.3 μM in the post-treatment assay, respectively. During virus replication steps, compounds 4 and 5 exhibited stronger inhibition of viral RNA and viral protein synthesis in late stages (18 and 24 h) than in early stages (6 and 12 h). Interestingly, compounds 4 and 5 inhibited both viral entry by hemagglutination inhibition and viral replication by inhibition of viral RNA and viral protein synthesis, but not viral protease. These results suggest that compounds isolated from E. cava have strong antiviral activity against PEDV, inhibiting viral entry and/or viral replication, and may be developed into natural therapeutic drugs against coronavirus infection. 相似文献
14.
Choi JY Lee SH Park CY Heo WD Kim JC Kim MC Chung WS Moon BC Cheong YH Kim CY Yoo JH Koo JC Ok HM Chi SW Ryu SE Lee SY Lim CO Cho MJ 《The Journal of biological chemistry》2002,277(24):21630-21638
Plants express numerous calmodulin (CaM) isoforms that exhibit differential activation or inhibition of CaM-dependent enzymes in vitro; however, their specificities toward target enzyme/protein binding are uncertain. A random peptide library displaying a 22-mer peptide on a bacteriophage surface was constructed to screen peptides that specifically bind to plant CaM isoforms (soybean calmodulin (ScaM)-1 and SCaM-4 were used in this study) in a Ca2+-dependent manner. The deduced amino acid sequence analyses of the respective 80 phage clones that were independently isolated via affinity panning revealed that SCaM isoforms require distinct amino acid sequences for optimal binding. SCaM-1-binding peptides conform to a 1-5-10 ((FILVW)XXX(FILV) XXXX(FILVW)) motif (where X denotes any amino acid), whereas SCaM-4-binding peptide sequences conform to a 1-8-14 ((FILVW)XXXXXX(FAILVW)XXXXX(FILVW)) motif. These motifs are classified based on the positions of conserved hydrophobic residues. To examine their binding properties further, two representative peptides from each of the SCaM isoform-binding sequences were synthesized and analyzed via gel mobility shift assays, Trp fluorescent spectra analyses, and phosphodiesterase competitive inhibition experiments. The results of these studies suggest that SCaM isoforms possess different binding sequences for optimal target interaction, which therefore may provide a molecular basis for CaM isoform-specific function in plants. Furthermore, the isolated peptide sequences may serve not only as useful CaM-binding sequence references but also as potential reagents for studying CaM isoform-specific function in vivo. 相似文献
15.
Cha KB Douglas KR Potok MA Liang H Jones SN Camper SA 《Mechanisms of development》2004,121(2):183-194
Wnt signaling is important in organogenesis, and aberrant signaling in mature cells is associated with tumorigenesis. Several members of the Wnt family of signaling molecules are expressed in the developing pituitary gland. Wnt5a is expressed in the neuroectoderm that induces pituitary gland development and has been proposed to influence pituitary cell specification. We discovered that mice deficient in Wnt5a display abnormal morphology in the dorsal part of the developing pituitary. The expression of downstream effectors of the canonical Wnt pathway is not altered, and expression of genes in other signaling pathways such as Shh, Fgf8, Fgf10 and Fgfr2b is intact. Prop1 and Hesx1 are also important for normal shape of the pituitary primordium, but their expression is unaltered in the Wnt5a mutants. Specification of the hormone-producing cell types of the mature anterior pituitary gland occurs appropriately. This study suggests that the primary role of Wnt5a in the developing pituitary gland is in establishment of the shape of the gland. 相似文献
16.
Bae SW Kim HS Cha YN Park YS Jo SA Jo I 《Biochemical and biophysical research communications》2003,306(4):981-987
Bradykinin (BK) acutely increases endothelial nitric oxide (NO) production by activating endothelial NO synthase (eNOS), and this increase is in part correlated with enhanced phosphorylation/dephosphorylation of eNOS by several protein kinases and phosphatases. However, the signaling mechanisms producing this increase are still controversial. In an attempt to delineate the acute effect of BK on endothelial NO production, confluent bovine aortic endothelial cells were incubated with BK, and NO production was measured by NO-specific chemiluminescence. Significant increase in NO levels was detected as early as 1 min after BK treatment, with concomitant increase in the phosphorylation of Ser(1179) (bovine sequence) site of eNOS (eNOS-Ser(1179)). This acute effect of BK on both increases was blocked only by treatment of protein kinase A inhibitor H-89, but not by the inhibitors of calmodulin-dependent kinase II and protein kinase B, suggesting that the rapid increase in NO production by BK is mediated by the PKA-dependent phosphorylation of eNOS-Ser(1179). 相似文献
17.
SNP identification, linkage disequilibrium, and haplotype analysis for a 200-kb genomic region in a Korean population 总被引:2,自引:0,他引:2
Understanding patterns of linkage disequilibrium (LD) across genomes may facilitate association mapping studies to localize genetic variants influencing complex diseases, a recognition that led to the International Haplotype Mapping Project (HapMap). Divergent patterns of haplotype frequency and LD across global populations require that the HapMap database be supplemented with haplotype and LD data from additional populations. We conducted a pilot study of the LD and haplotype structure of a genomic region in a Korean population. A total of 165 SNPs were identified in a 200-kb region of 22q13.2 by direct sequencing. Unphased genotype data were generated for 76 SNPs in 90 unrelated Korean individuals. LD, haplotype diversity, and recombination rates were assessed in this region and compared with the HapMap database. The pattern of LD and haplotype frequencies of Korean samples showed a high degree of similarity with Japanese data. There was a strong correlation between high LD and low recombination frequency in this region. We found considerable similarities in local LD patterns between three Asian populations (Han Chinese, Japanese, and Korean) and the CEPH population. Haplotype frequencies were, however, significantly different between them. Our results should further the understanding of distinctive Korean genomic features and assist in designing appropriate association studies. 相似文献
18.
Jae-Jin Lee Hyun Ji Lee Gi Seon Jang Ja Myoung Yu Ji Yoon Cha Su Jeong Kim Eun Bit Lee Myung Kyum Kim 《Journal of microbiology (Seoul, Korea)》2013,51(3):305-311
Strain DY59T, a Gram-positive non-motile bacterium, was isolated from soil in South Korea, and was characterized to determine its taxonomic position. Phylogenetic analysis based on the 16S rRNA gene sequence of strain DY59T revealed that the strain DY59T belonged to the family Deinococcaceae in the class Deinococci. The highest degree of sequence similarities of strain DY59T were found with Deinococcus radiopugnans KACC 11999T (99.0%), Deinococcus marmoris KACC 12218T (97.9%), Deinococcus saxicola KACC 12240T (97.0%), Deinococcus aerolatus KACC 12745T (96.2%), and Deinococcus frigens KACC 12220T (96.1%). Chemotaxonomic data revealed that the predominant fatty acids were iso-C15:0 (19.0%), C16:1 ω7c (17.7%), C15:1 ω6c (12.6%), iso-C17:0 (10.3%), and iso-C17:1 ω9c (10.3%). A complex polar lipid profile consisted of a major unknown phosphoglycolipid. The predominant respiratory quinone is MK-8. The cell wall peptidoglycan contained D-alanine, L-glutamic acid, glycine, and L-ornithine (di-amino acid). The novel strain showed resistance to gamma radiation, with a D10 value (i.e. the dose required to reduce the bacterial population by 10-fold) in excess of 5 kGy. Based on the phylogenetic, chemotaxonomic, and phenotypic data, strain DY59T (=KCTC 33033T =JCM 18581T) should be classified as a type strain of a novel species, for which the name Deinococcus swuensis sp. nov. is proposed. 相似文献
19.
Cha IS Kwon J Park SH Nho SW Jang HB Park SB del Castillo CS Hikima J Aoki T Jung TS 《Journal of Proteomics》2012,75(17):5166-5175
The proteomic response to bacterial infection in a teleost fish (Paralichthys olivaceus) infected with Streptococcus parauberis was analyzed using label-free protein quantitation coupled with LC-MS(E) tandem mass spectrometry. A total of 82 proteins from whole kidney, a major lymphoid organ in this fish, were found to be differentially expressed between healthy and diseased fish analyzed 6, 24, 72 and 120 h post-infection. Among the differentially expressed proteins, those involved in mediating immune responses (e.g., heat shock proteins, cathepsins, goose-type lysozyme and complement components) were most significantly up-regulated by infection. In addition, cell division cycle 48 (CDC48) and calreticulin, which are associated with cellular recovery and glycoprotein synthesis, were up-regulated in the universal protein group, whereas the other proteins in that group were down-regulated. There was continuous activation of expression of immune-associated proteins during infection, but there was also loss of expression of proteins not involved in immune function. We expect that our findings regarding immune response at the protein level would offer new insight into the systemic response to bacterial infection of a major immune organ in teleost fish. 相似文献
20.
Aeryun Kim Stephanie L. Servetas Jieun Kang Jinmoon Kim Sungil Jang Yun Hui Choi Hanfu Su Yeong-Eui Jeon Youngmin A. Hong Yun-Jung Yoo D. Scott Merrell Jeong-Heon Cha 《Journal of microbiology (Seoul, Korea)》2016,54(12):846-852
The array of outer membrane proteins (OMPs) found in Helicobacter pylori provides a crucial component for persistent colonization within the gastric niche. Not only does H. pylori harbor a wide number of OMPs, but these OMPs often vary across strains; this likely contributes to immune evasion, adaptation during long term colonization, and potentially differential disease progression. Previous work from our group described OMP differences among the Bab family (babA, babB, and babC) and Hom family (homA and homB) from 80 American H. pylori clinical isolates (AH) and 80 South Korean H. pylori clinical isolates (KH). In the current study, we expanded our investigation to include the less well characterized Hom family member, HomC. 相似文献