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991.
Expression of tetanus toxin fragment C in yeast: gene synthesis is required to eliminate fortuitous polyadenylation sites in AT-rich DNA. 总被引:6,自引:1,他引:5 下载免费PDF全文
M A Romanos A J Makoff N F Fairweather K M Beesley D E Slater F B Rayment M M Payne J J Clare 《Nucleic acids research》1991,19(7):1461-1467
992.
993.
Experimental evaluation of the mass of food withdrawn by larvae of the Siberian moth during their development on larch, cedar pine, fir, spruce, and common pine was carried out. The obtained dependences between the masses of larvae and food withdrawn by them can be directly used to determine the withdrawn food rate of Siberian moth on each of the Siberian conifer species. 相似文献
994.
A rat adrenal cDNA library was screened by colony hybridization using a rat cDNA fragment of type I angiotensin II receptor (AT1A) previously isolated from the kidney. Two cDNA clones were identified, designated as AT1B, to have a nucleotide sequence highly homologous to and yet distinct from AT1A. The amino acid sequence of AT1B consists of 359 amino acid residues and has 96% identity with AT1A. No conspicuous difference in the ligand binding characteristics was observed between AT1A and AT1B. The mRNA for AT1B was expressed in many tissues as is the case with AT1A, and most abundantly expressed in the adrenal glands in the Sprague-Dawley rats. The existence of two subtypes in the rat type I angiotensin II receptor might explain the diverse actions of angiotensin II in various tissues. 相似文献
995.
P Reddy N Fredd-Kuldell E Liberman A Peterkofsky 《Protein expression and purification》1991,2(2-3):179-187
We present methods for the rapid, simple purification of Enzyme I, HPr, and Protein IIIGlc of the Escherichia coli phosphoenolpyruvate:sugar phosphotransferase system (PTS) using plasmids overproducing gene products. The gene for HPr (ptsH) was cloned into the expression vector pKC30. A simple procedure was devised for the purification to homogeneity of this protein from extracts of heat-induced cells containing pKC30/ptsH recombinant clone. The genes for Enzyme I (ptsI) and Protein IIIGlc (crr) were cloned separately into the expression vector pRE1. Rapid purification procedures were developed for the isolation of homogeneous preparations of these two proteins from extracts of heat-induced cells containing pRE1/ptsI and pRE1/crr recombinants. From about 6 g of cells, these procedures yielded 100, 86, and 50 mg of Enzyme I, HPr, and Protein IIIGlc, respectively. The activity of the proteins purified by these methods was comparable to that of the proteins isolated by previously published less efficient procedures. 相似文献
996.
In the study of P. aeruginosa cultures, serogroup O11, strains agglutinated simultaneously by factor sera 11b and 11c have been detected. In experiments on cross agglutination and agglutinin adsorption the antigenic structure of these strains, viz. 11a, 11b and 11c, has been determined. 相似文献
997.
998.
M Hessing R A Vlooswijk T M Hackeng D Kanters B N Bouma 《Journal of immunology (Baltimore, Md. : 1950)》1990,144(1):204-208
C4b-binding protein (C4BP) is a multimeric plasma protein, which regulates the classical pathway of the C system. C4BP interacts with C C4b on a domain located in a 48-kDa chymotryptic fragment. We now demonstrate that C4BP contains heparin-binding fragments, which are located within the C4b binding domain. We have used an assay using heparin coupled to Sepharose CL-6B to show that 125I-C4BP binds to heparin in a time-dependent, saturable, and reversible manner. Binding could be inhibited by purified 48-kDa fragments and direct binding on the 48-kDa fragments to heparin-Sepharose was demonstrated by SDS-PAGE. mAb against native C4BP and the isolated 160-kDa central core fragment were evaluated for their ability to block the binding of 125I-C4BP to heparin and C4b. The relative efficacy of mAb against intact C4BP in blocking C4BP binding to heparin-Sepharose was similar to that for blocking 125I-C4BP binding to C4b. In addition, heparin blocked the binding of 125I-C4BP to C4b and vice versa. It is therefore likely that the heparin-binding fragments are localized on or close to the C4b-binding site of C4BP. 相似文献
999.
J.J. Virgen-Ortíz V. Ibarra-Junquera P. Escalante-Minakata J.A. Osuna-Castro J. de J. Ornelas-Paz N.A. Mancilla-Margalli R.L. Castañeda-Aguilar 《Analytical biochemistry》2013
This work presents a rapid and simple freeze centrifugation method to concentrate dilute protein solutions for detection by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS–PAGE) Coomassie blue staining. Moreover, a simple way to assemble a cryoconcentration device is presented, and its use is discussed. Commercial purified protein standard and an enzyme with high fructosyltransferase (FTase) activity, coming from target fractions obtained by chromatographic separation, were used as an example. FTase, coming directly from the chromatographic fractions, was difficult to view through SDS–PAGE analysis; however, it was easily visualized, and its activity was enhanced, after the application of the freeze centrifugation protocol presented here. 相似文献
1000.
N. Pan 《Redox report : communications in free radical research》2013,18(2):149-154
SummaryWe have investigated antioxidant actions of acteoside (ACT) and another natural phenylpropanoid glycoside, cistanoside F (CIS-F) on lipid peroxidation in rat liver mitochondria (RLM) and rat liver mitochondrial lipid (RLML) liposomes induced by Fe2+/ADP. A synthetic ACT analogue, TX-1847, was also examined. Oxygen consumption, the formation of thiobarbituric acid reactive substances (TBARs) and glutathione concentration were determined simultaneously during lipid peroxidation. The radical scavenging activity of the compounds was evaluated by using 1,1-diphenyl-2-picrylhydrazyl. ACT and its analogs produced dose-dependent inhibitions of mitochondrial and liposomal lipid peroxidation (ACT ≈ CIS-F > TX-1847). Their radical scavenging activities were ranked as follows: TX-1847 > ACT > CIS-F. ACT, CIS-F, and TX-1847 spared reduced glutathione (GSH) during mitochondrial lipid peroxidation. The radical scavenging activities of the compounds did not parallel their anti-peroxidative activities. The data are consistent with the idea that the inhibitory activities of phenylpropanoids were primarily due to a radical chain-breaking mechanism. The sugar moieties in ACT and CIS-F, and/or the conformational structure of the compounds, also seem to play an important role in their inhibitory effects on lipid peroxidation. 相似文献