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A Gram-negative, non-motile, non-spore-forming, small, orange, rod-shaped bacterium was isolated from soil in South Korea and characterized to determine its taxonomic position. Phylogenetic analysis based on 16S rRNA gene sequence examination revealed that strain PB323T belongs to the family Sphingomonadaceae. The highest degree of sequence similarity was found with Sphingomonas kaistensis PB56T (98.9%), followed by Sphingomonas astaxanthinifaciens TDMA-17T (98.3%). Chemotaxonomic characteristics (the G+C content of the genomic DNA 69.0 mol%, Q-10 quinone system, C18:1 ω7c/ω9t/ω12t, C16:1 ω7c/C15:0 iso 2OH, C17:1 ω6c, and C16:0 as the major fatty acids) corroborated assignment of strain PB323T to the genus Sphingomonas. Results of physiological and biochemical tests clearly demonstrate that strain PB323T represents a distinct species and support its affiliation with the genus Sphingomonas. Based on these data, PB323T (=KCTC 12341T =JCM 16603T =KEMB 9004-003T) should be classified as a type strain of a novel species, for which the name Sphingomonas humi sp. nov. is proposed.  相似文献   
23.
The induction of conformationally restricted N-(aryl or heteroaryl)-3-azabicyclo[3.1.0]hexane derivatives at P2 region of compounds of 2-cyanopyrrolidine class was explored to develop novel DPP-IV inhibitors. The synthesis, structure–activity relationship, and selectivity against related proteases are delineated.  相似文献   
24.
The GRAM domain was found in glucosyltransferases, myotubularins and other membrane-associated proteins. So far, functions for majority of these proteins are yet to be uncovered. In order to address the evolutionary and functional significance of this family members, we have performed a comprehensive investigation on their genome-wide identification, phylogenetic relationship and expression divergence in five different organisms representing monocot/dicot plants, vertebrate/invertebrate animals and yeast, namely, Oryza sativa, Arabidopsis thaliana, Mus musculus, Drosophila melanogaster and Saccharomyces cerevisiae, respectively. We have identified 65 members of GRAM domain family from these organisms. Our data revealed that this family was an ancient group and various organisms had evolved into different family sizes. Large-scale genome duplication and divergence in both expression patterns and functions were significantly contributed to the expansion and retention of this family. Mouse and Drosophila members showed higher divergences in their proteins as indicated by higher Ka/Ks ratios and possessed multiple domains in various combinations. However, in plants, their protein functions were possibly retained with a relatively low divergence as signified by lower Ka/Ks ratios and only one additional domain was combined during evolution. On the other hand, this family in all five organisms exhibited high divergence in their expression patterns both at tissue level and under various biotic and abiotic stresses. These highly divergent expression patterns unraveled the complexity of functions of GRAM domain family. Each member may play specialized roles in a specific tissue or stress condition and may function as regulators of environmental and hormonal signaling.  相似文献   
25.
The spectral properties of the discrimination of pattern orientation in freely flying honeybees (Apis mellifera) were examined. Bees were trained to discriminate between two random black/white gratings oriented perpendicularly to each other, one of which was associated with a reward. Subsequently the bees were tested on two-colour gratings or gratings consisting of grey and coloured stripes, providing a range of different chromatic contrasts, luminance contrasts and specific channel contrasts. The results of these experiments indicate that orientation analysis in the honeybee is mediated almost exclusively by the green receptor channel, although the bee's visual system as a whole is endowed with excellent trichromatic colour vision.  相似文献   
26.
Effects of prolactin (PRL), bromocriptine (Br), testosterone propionate (TP), dihydrotestosterone (DHT) and the combination of these androgens with PRL/Br on the total lipid, total cholesterol, total glyceride glycerols, total phospholipid and their fractions in seminal vesicles of castrated mature monkeys were studied. Glyceride glycerols formed the major portion (50%) of total lipids in normal monkeys. Cholesterol and phospholipids were of equal share (25%). Esterified cholesterol formed major share (75%) of total cholesterol. Diacyl glycerol was the major (60%) glyceride glycerol and phosphatidyl choline and ethanolamine were the major phospholipid classes. Except triacyl glycerol castration markedly decreased all the lipid classes. PRL restored normal free and esterified cholesterol and phosphatidyl inositol but Br invariably decreased all the lipid classes. TP/DHT treatment stimulated the free and esterified cholesterol more than the control; it restored the normal glyceride glycerols. Phosphatidyl inositol, choline and ethanolamine were stimulated by androgens and other phospholipid classes were brought to normal. Addition of PRL + TP/DHT markedly increased esterified cholesterol, phosphatidyl inositol, choline, ethanolamine and phosphatidic acid. In all these aspects, Br counteracted the effects of androgens and PRL.  相似文献   
27.
Interactions of protein kinase CK2 subunits   总被引:3,自引:0,他引:3  
Several approaches have been used to study the interactions of the subunits of protein kinase CK2. The inactive mutant of CK2 that has Asp 156 mutated to Ala (CK2A156) is able to bind the CK2 subunit and to compete effectively in this binding with wild-type subunits and . The interaction between CK2A156 and CK2 was also demonstrated by transfection of epitope-tagged cDNA constructs into COS-7 cells. Immunoprecipitation of epitope-tagged CK2A156 coprecipitated the subunit and vice-versa. The assay of the CK2 activity of the extracts obtained from cells transiently transfected with these different subunits yielded some surprising results: The CK2 specific phosphorylating activity of these cells transfected with the inactive CK2A156 was considerably higher than the control cells transfected with vectors alone. Assays of the immunoprecipitated CK2A156 expressed in these cells, however, demonstrated that the mutant was indeed inactive. It can be concluded that transfection of the inactive CK2A156 affects the endogenous activity of CK2. Transfection experiments with CK2 and subunits and CK2A156 were also used to confirm the interaction of CK2 with the general CDK inhibitor p21WAF1/CIP1 co-transfected into these cells. Finally a search in the SwissProt databank for proteins with properties similar to those derived from the amino acid composition of CK2 indicated that CK2 is related to protein phosphatase 2A and to other phosphatases as well as to a subunit of some ion-transport ATPases.  相似文献   
28.
Integration of living cells with novel microdevices requires the development of innovative technologies for manipulating cells. Chemical surface patterning has been proven as an effective method to control the attachment and growth of diverse cell populations. Patterning polyelectrolyte multilayers through the combination of layer‐by‐layer self‐assembly technique and photolithography offer a simple, versatile, and silicon compatible approach that overcomes chemical surface patterning limitations, such as short‐term stability and low‐protein adsorption resistance. In this study, direct photolithographic patterning of two types of multilayers, PAA (poly acrylic acid)/PAAm (poly acryl amide) and PAA/PAH (poly allyl amine hydrochloride), were developed to pattern mammalian neuronal, skeletal, and cardiac muscle cells. For all studied cell types, PAA/PAAm multilayers behaved as a cytophobic surface, completely preventing cell attachment. In contrast, PAA/PAH multilayers have shown a cell‐selective behavior, promoting the attachment and growth of neuronal cells (embryonic rat hippocampal and NG108‐15 cells) to a greater extent, while providing little attachment for neonatal rat cardiac and skeletal muscle cells (C2C12 cell line). PAA/PAAm multilayer cellular patterns have also shown a remarkable protein adsorption resistance. Protein adsorption protocols commonly used for surface treatment in cell culture did not compromise the cell attachment inhibiting feature of the PAA/PAAm multilayer patterns. The combination of polyelectrolyte multilayer patterns with different adsorbed proteins could expand the applicability of this technology to cell types that require specific proteins either on the surface or in the medium for attachment or differentiation, and could not be patterned using the traditional methods. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009  相似文献   
29.
Proline (Pro) plays a versatile role in cell metabolism and physiology. Pro and hydroxypro are major imino acids present in collagen, an important connective tissue protein, essential for wound healing, which is a primary response to tissue injury. This study explains the role of l-pro on cutaneous wound healing in rats when administered both topically and orally. Open excision wounds were made on the back of rats, and 200 μl (200 mg) of pro was administered topically and orally once daily to the experimental rats until the wounds healed completely. The control wounds were left untreated. Granulation tissues formed were removed after day 4 and 8 of post excision wounding, and biochemical parameters such as total protein, collagen, hexosamine, and uronic acid were estimated. Levels of enzymatic and non-enzymatic antioxidants such as catalase, superoxide dismutase, glutathione peroxidase, ascorbic acid, and reduced glutathione were evaluated along with lipid peroxides in the granulation tissues. Tensile strength and period of epithelialization were also measured. It was observed that the treated wounds healed very fast as evidenced by augmented rates of epithelialization and wound contraction, which was also confirmed by histological examinations. The results strappingly authenticate the beneficial effects of the topical administration of l-proline in the acceleration of wound healing than the oral administration and control.  相似文献   
30.
Biotechnology Letters - Colorectal cancer (CRC) is the third most prevalent type of cancer in the United States. The treatment options for cancer include surgery, chemotherapy, radiation,...  相似文献   
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