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1.
Summary With the -amylase promoter and ribosome binding site,Bacillis subtilis was used to express the sweet plant protein thaumatin II cDNA fused in the correct reading frame to the -amylase leader peptide. The r-thaumatin was purified from the medium on a S-Sepharose column and detected with western blots by sheep -thaumatin antibodies. The r-thaumatin and authentic thaumatin were the same size when reduced by 2-ME and the same size when not reduced. 相似文献
2.
Charles Illingworth Gregg Larson Goran Hellekant 《Journal of industrial microbiology & biotechnology》1989,4(1):37-42
Summary To produce and direct the export inStreptomyces lividans of the sweet plant protein thaumatin, thaumatin II cDNA was fused in the correct reading frame to the -galactosidase leader peptide, under the control of the -galactosidase promoter and ribosome binding site. The export of the recombinant thaumatin may allow the correct formation of the thaumatin disulfide bonds. The recombinant thaumatin was purified from the medium on an S-Sepharose column and detected with western blots by sheep -thaumatin antibodies. The recombinant thaumatin was the same size as authentic thaumatin and changed position on an acrylamide gel in response to reduction by 2-mercaptoethanol in the same manner. 相似文献
3.
Edward M. Mills Palur G. Gunasekar Goran Pavlakovic Gary E. Isom 《Journal of neurochemistry》1996,67(3):1039-1046
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We investigated gene expression patterns that occur during taro corm development. Two-dimensional gel electrophoresis identified several different prevalent proteins that accumulate during corm development. Microsequencing studies indicated that some of these proteins are related to taste-modifying proteins, such as curculin and miraculin, and proteins found in other storage organs, such as sporamin and the Kunitz trypsin inhibitor. A curculin-encoding cDNA clone, designated as TC1, was identified that corresponds to a highly prevalent 1-kb corm mRNA. The TC1 mRNA accumulates during corm development, is more prevalent in corm apical than basal regions, and is either absent, or present at low concentrations, in other vegetative organs such as the leaf and root. In situ hybridization experiments showed that the TC1 mRNA is highly concentrated in corm storage parenchyma cells and is absent, or present in reduced concentrations, in other corm cells and tissues. Our results show that corm development is associated with the differentiation of specialized cells and tissues, and that these differentiation events are coupled with the temporal and spatial expression of corm-specific genes. 相似文献
7.
The complement system is an essential element of the innate immune response that becomes activated upon recognition of molecular patterns associated with microorganisms, abnormal host cells, and modified molecules in the extracellular environment. The resulting proteolytic cascade tags the complement activator for elimination and elicits a pro‐inflammatory response leading to recruitment and activation of immune cells from both the innate and adaptive branches of the immune system. Through these activities, complement functions in the first line of defense against pathogens but also contributes significantly to the maintenance of homeostasis and prevention of autoimmunity. Activation of complement and the subsequent biological responses occur primarily in the extracellular environment. However, recent studies have demonstrated autocrine signaling by complement activation in intracellular vesicles, while the presence of a cytoplasmic receptor serves to detect complement‐opsonized intracellular pathogens. Furthermore, breakthroughs in both functional and structural studies now make it possible to describe many of the intricate molecular mechanisms underlying complement activation and the subsequent downstream events, as well as its cross talk with, for example, signaling pathways, the coagulation system, and adaptive immunity. We present an integrated and updated view of complement based on structural and functional data and describe the new roles attributed to complement. Finally, we discuss how the structural and mechanistic understanding of the complement system rationalizes the genetic defects conferring uncontrolled activation or other undesirable effects of complement. 相似文献
8.
Ruggero Vigliaturo Alessandra Marengo Erica Bittarello Ileana Prez‐Rodríguez Goran Drai Reto Gier 《Geobiology》2020,18(5):606-618
Neutrophilic, microaerobic Fe(II)‐oxidizing bacteria (FeOB) from marine and freshwater environments are known to generate twisted ribbon‐like organo‐mineral stalks. These structures, which are extracellularly precipitated, are susceptible to chemical influences in the environment once synthesized. In this paper, we characterize the minerals associated with freshwater FeOB stalks in order to evaluate key organo‐mineral mechanisms involved in biomineral formation. Micro‐Raman spectroscopy and Field Emission Scanning Electron Microscopy revealed that FeOB isolated from drinking water wells in Sweden produced stalks with ferrihydrite, lepidocrocite and goethite as main mineral components. Based on our observations made by micro‐Raman Spectroscopy, field emission scanning electron microscopy and scanning transmission electron microscope combined with electron energy‐loss spectroscopy, we propose a model that describes the crystal‐growth mechanism, the Fe‐oxidation state, and the mineralogical state of the stalks, as well as the biogenic contribution to these features. Our study suggests that the main crystal‐growth mechanism in stalks includes nanoparticle aggregation and dissolution/re‐precipitation reactions, which are dominant near the organic exopolymeric material produced by the microorganism and in the peripheral region of the stalk, respectively. 相似文献
9.
Renata Jurišić Grubešić Goran Srečnik Dario Kremer Jadranka Vuković Rodríguez Toni Nikolić Sanda Vladimir‐Knežević 《化学与生物多样性》2013,10(7):1305-1316
A rapid reversed‐phase (RP) high‐performance liquid chromatography method was developed and applied for simultaneous separation, and determination of flavonoids and phenolic acids in eight Plantago L. taxa (P. altissima L., P. argentea Chaix , P. coronopus L., P. holosteum Scop . ssp. depauperata Pilger , P. holosteum ssp. holosteum, P. holosteum ssp. scopulorum (Degen) Horvati? , P. lagopus L., and P. maritima L.) growing in Croatia. Chromatographic separation was carried out on Zorbax Eclipse XDB‐C18 using gradient elution with a H2O (pH 2.5, adjusted with CF3COOH) and MeCN mixture at 30°. The contents of analyzed phenolic compounds (% of the dry weight of the leaves, dw) varied among examined species: rutin (max. 0.024%, P. argentea), hyperoside (max. 0.020%, P. lagopus), quercitrin (max. 0.013%, P. holosteum ssp. holosteum), quercetin (max. 0.028%, P. holosteum ssp. scopulorum), chlorogenic acid (max. 0.115%, P. lagopus), and caffeic acid (max. 0.046%, P. coronopus). Isoquercitrin was detected only in P. argentea (0.020%), while isochlorogenic acid content was below limit of quantification in all investigated species. Multivariate analyses (UPGMA and PCA) showed significant differences in contents of investigated polyphenolic compounds between different Plantago taxa. Accordingly, investigated substances might be employed as chemotaxonomic markers in the study of the complex genus Plantago. 相似文献
10.
Interaction of Insulin-Like Growth Factor-Binding Protein 2 with α2-Macroglobulin in the Circulation
Insulin-like growth factors (IGFs) play active role in mitogenic and metabolic processes. In the peripheral circulation, they are mostly bound to specific IGF-binding proteins (IGFBPs). Proteolysis of IGFBPs releases free, active IGFs. IGFBP-2 is the second most abundant of the six binding proteins and its concentration increases in catabolic states. The possible interaction between IGFBP-2 and other proteins in the circulation was investigated in this study. Our results showed that IGFBP-2 associates with α2-macroglobulin (α2M), a protease inhibitor. Formation of IGFBP-2/α2M complexes most likely contributes to the regulation of IGFBP-2 proteolysis and, thus, the activity of IGFs. 相似文献