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51.
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
52.
Victor E. Marquez Lak S. Jeong Marc C. Nicklaus Cliff George 《Nucleosides, nucleotides & nucleic acids》2013,32(3-5):555-558
Abstract The efficient DAST fluorination of deoxy-4′-thiopyrimidine nucleosides is reported. The cytidine analogue 3b was marginally effective against HIV. 相似文献
53.
54.
The intelligent mobile robot with sensors and image processing embedded system combines the suction and aerodynamic attraction to achieve good balance between strong adhesion force and high mobility. Experimental results showed that the robot can move upward on the wall at the speed of 2.9 m/min and carry 5 kg payload in addition to 2.5 kg self-weight, which record the highest payload capacity among climbing robots of similar size. It also implements object detection ability using effective color transform and segmentation technique for the exact target detection on the wall using a embedded camera system, communication module and several active sensors. 相似文献
55.
Joon-Goo Jung Yong Jae Lee Natarajan Velmurugan Young-Joon Ko Hyang-Sim Lee Ki Jun Jeong 《Journal of industrial microbiology & biotechnology》2013,40(7):705-713
For effective control of foot-and-mouth disease (FMD), the development of rapid diagnostic systems and vaccines are required against its etiological agent, FMD virus (FMDV). To accomplish this, efficient large-scale expression of the FMDV VP1 protein, with high solubility, needs to be optimized. We attempted to produce high levels of a serotype O FMDV VP1 epitope in Escherichia coli. We identified the subtype-independent serotype O FMDV VP1 epitope sequence and used it to construct a glutathione S-transferase (GST) fusion protein. For efficient production of the FMDV VP1 epitope fused to GST (VP1e–GST), four E. coli strains and three temperatures were examined. The conditions yielding the greatest level of VP1e–GST with highest solubility were achieved with E. coli BL21(DE3) at 25 °C. For high-level production, fed-batch cultures were conducted in 5-l bioreactors. When cells were induced at a high density and complex feeding solutions were supplied, approximately 11 g of VP1e–GST was obtained from a 2.9-l culture. Following purification, the VP1 epitope was used to immunize rabbits, and we confirmed that it induced an immune response. 相似文献
56.
Koeun Han Hee-Jin Jeong Joohee Sung Young Soo Keum Myeong-Cheoul Cho Jeong-Han Kim Jin-Kyung Kwon Byung-Dong Kim Byoung-Cheorl Kang 《Molecular breeding : new strategies in plant improvement》2013,31(3):537-548
Pungency in pepper (Capsicum annuum L.) has unique characteristics due to the alkaloid compound group, capsaicinoids, which includes capsaicin. Although capsaicinoids have been proved to have pharmacological and physiological effects on human health, the application of capsaicinoids has been limited because of their pungency. Capsinoids found in non-pungent peppers share closely related structures with capsaicinoids and show similar biological effects. Previous studies demonstrated that mutations in the p-AMT gene were related to the production of capsinoids; however, the pathway of capsinoid synthesis has not yet been fully elucidated. In this study, we performed genetic analysis to determine the mechanism of capsinoid synthesis using a F6 recombinant inbred line population. In this population, the presence/absence of capsinoids co-segregated with the genotype of the Pun1 locus, without exception. In addition, we screened the patterns of capsinoid synthesis and the correlation between the Pun1 locus and capsinoid synthesis in p-AMT mutant accessions. In Capsicum germplasms, we selected amino-acid-substituted mutants in the PLP binding domain of the p-AMT gene. Capsinoids were not synthesized with the recessive pun1 gene, regardless of the p-AMT genotype, and no relationship was found between p-AMT mutant type and capsinoid content. We concluded that the Pun1 gene, which is responsible for capsaicinoid synthesis, also controls capsinoid synthesis. 相似文献
57.
Jaekwang Jeong Ivonne Lisinski Anil K. G. Kadegowda Hyunsu Shin F. B. Peter Wooding Brian R. Daniels Jerome Schaack Ian H. Mather 《Traffic (Copenhagen, Denmark)》2013,14(9):974-986
Milk lipid is secreted by a unique process, during which triacylglycerol droplets bud from mammary cells coated with an outer bilayer of apical membrane. In all current schemes, the integral protein butyrophilin 1A1 (BTN) is postulated to serve as a transmembrane scaffold, which interacts either with itself or with the peripheral proteins, xanthine oxidoreductase (XOR) and possibly perilipin‐2 (PLIN2), to form an immobile bridging complex between the droplet and apical surface. In one such scheme, BTN on the surface of cytoplasmic lipid droplets interacts directly with BTN in the apical membrane without binding to either XOR or PLIN2. We tested these models using both biochemical and morphological approaches. BTN was concentrated in the apical membrane in all species examined and contained mature N‐linked glycans. We found no evidence for the association of unprocessed BTN with intracellular lipid droplets. BTN‐enhanced green fluorescent protein was highly mobile in areas of mouse milk‐lipid droplets that had not undergone post‐secretion changes, and endogenous mouse BTN comprised only 0.5–0.7% (w/w) of the total protein, i.e. over 50‐fold less than in the milk‐lipid droplets of cow and other species. These data are incompatible with models of milk‐lipid secretion in which BTN is the major component of an immobile global adhesive complex and suggest that interactions between BTN and other proteins at the time of secretion are more transient than previously predicted. The high mobility of BTN in lipid droplets marks it as a potential mobile signaling molecule in milk . 相似文献
58.
The dairy industry is a multi-billion dollar industry catering the nutritional needs of all age groups globally through the supply of milk. Clinical mastitis has a severe impact on udder tissue and is also an animal welfare issue. Moreover, it significantly reduces animal value and milk production. Mammary tissue damage reduces the number and activity of epithelial cells and consequently contributes to decreased milk production. The high incidence, low cure rate of this highly economic and sometimes deadly disease is an alarming for dairy sector as well as policy makers. Bovine mammary epithelial cells (MECs) and their stem cells are very important in milk production and bioengineering. The adult mammary epithelium consists of two main cell types; an inner layer of luminal epithelial cells, which produce the milk during lactation, and an outer layer of myoepithelial cells resting on a basement membrane, which are responsible for pushing the milk through the ductal network to the teat cistern. Inner layer of columner/luminal cells of bovine MECs, is characterized by cytokeratin18, 19 (CK18, CK19) and outer layer such as myoepithelial cells which are characterized by CK14, α-smooth muscle actin (α-SMA) and p63. Much work has been done in mouse and human, on mammary gland stem cell research, particularly in cancer therapy, but stem cell research in bovine is still in its infancy. Such stem/progenitor cell discoveries in human and mouse mammary gland bring some hope for application in bovines. These progenitors may be therapeutically adopted to correct the structural/cytological defects in the bovine udder due to mastitis. In the present review we focused on various kinds of stem/progenitor cells which can have therapeutic utility and their possibilities to use as a potential stem cell therapy in the management of bovine post-mastitis damage in orders to restore milk production. The possibilities of bovine mammary stem cell therapy offers significant potential for regeneration of tissues that can potentially replace/repair diseased and damaged tissue through differentiation into epithelial, myoepithelial and/or cuboidal/columnar cells in the udder with minimal risk of rejection and side effects. 相似文献
59.
Sangwoo Kim Kyowon Jeong Kunal Bhutani Jeong Ho Lee Anand Patel Eric Scott Hojung Nam Hayan Lee Joseph G Gleeson Vineet Bafna 《Genome biology》2013,14(8):R90
Detection of somatic variation using sequence from disease-control matched data sets is a critical first step. In many cases including cancer, however, it is hard to isolate pure disease tissue, and the impurity hinders accurate mutation analysis by disrupting overall allele frequencies. Here, we propose a new method, Virmid, that explicitly determines the level of impurity in the sample, and uses it for improved detection of somatic variation. Extensive tests on simulated and real sequencing data from breast cancer and hemimegalencephaly demonstrate the power of our model. A software implementation of our method is available at http://sourceforge.net/projects/virmid/. 相似文献
60.
Development of induced pluripotent stem cell (iPSC) technology introduced a novel way to derive pluripotent stem cells, but the genetic manipulation required to generate iPSCs may lead to uncontrolled tumorigenesis of the established cells and thus limit clinical feasibility of the technology. Numerous attempts have been made to date, and alternative reprogramming of somatic cells to reactivate cellular plasticity after differentiation has been suggested. As a result, it had become clear that cell-to-cell interactions and specific acellular environments can be utilized for somatic cell reprogramming. In our previous studies, embryonic stem cell (ESC)-like cells could be derived from transforming ovarian cells and fetal fibroblasts by cell-to-cell interaction or specific cell-mediated microenvironmental factor(s). This cellular event was induced without undertaking genetic manipulation of progenitor cells. Several differences were found between the cellular properties of niche-induced, ESC-like cells and those of genetically manipulated iPSCs and the referenced ESCs. Thus, we provided evidence that terminally differentiated somatic cells either acquire pluripotency-like activity or possess cellular and genetic plasticity under a specific microenvironment and/or cell-to-cell interaction. In this minireview, we discuss derivation of stem cell-like cells under specific microenvironmental conditions in terms of technical perspectives and limitations. 相似文献