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1.
Summary A new agglutinin has been isolated from the red algaGracilaria bursa-pastoris by affinity chromatography on a yeast mannan-Cellulofine column. This agglutinin was isolated as a monomeric glycoprotein with a relatively low molecular weight. It had an isoelectric point of 4.7 and contained large amounts of Gly, Asx and Glx. It agglutinated trypsin-treated rabbit erythrocytes at the low concentration of 30 ng/ml. The activity was inhibited only by glycoproteins bearing N-glycans. This agglutinin also showed mitogenic activity for mouse splenic lymphocytes.  相似文献   

2.
The hemolymph from various species of moths was analyzed for cross-reactivity with a panel of six monoclonal antibodies made against the hemolymph juvenile hormone binding protein ofManduca sexta. With the exception of one antibody, the immunoreactivity was limited to the sphingid family. One monoclonal antibody cross-reacted with a number of lepidopteran species; however, families such as Noctuidae and Pyralidae, known to have high affinity, low molecular weight juvenile hormone binding proteins, did not cross-react. Immunological cross-reactivity withManduca sexta juvenile hormone binding protein in several primitive moth families supports the current model of phylogenetic relationships in the order Lepidoptera.  相似文献   

3.
We have proposed a chemical chaperone therapy for lysosomal diseases, based on a paradoxical phenomenon that an exogenous competitive inhibitor of low molecular weight stabilizes the target mutant molecule and restores its catalytic activity as a molecular chaperone intracellularly. After Fabry disease experiments, we investigated a new synthetic chaperone compound N-octyl-4-epi-β-valienamine (NOEV) in a GM1-gangliosidosis model mice. Orally administered NOEV entered the brain through the blood-brain barrier, enhanced β-galactosidase activity, reduced the substrate storage, and clinically improved neurological deterioration. We hope that chemical chaperone therapy will prove useful for some patients with GM1-gangliosidosis and potentially other lysosomal storage diseases with central nervous system involvement. Received 10 October 2007; received after revision 31 October 2007; accepted 6 November 2007  相似文献   

4.
Summary The circadian clock in the unicellular algaGonyaulax polyedra is accelerated by a substance in extracts from the cells themselves. The extracts have been fractionated using the circadian rhythm of bioluminescence as bioassay. The active substance, termed gonyauline, has been isolated and characterized as a novel low molecular weight cyclopropanecarboxylic acid (S-methyl-cis-2-(methylthio) cyclopropanecarboxylic acid). Synthetic gonyauline has a similar shortening effect on the period of the circadian clock.  相似文献   

5.
Brief irradiation with a germicidal UV lamp of cells of red bean,Vigna angularis, cultured in suspension in a quartz flask caused the release into the culture medium of an endogenous substance with elicitor activity, as well as the accumulation of isoflavone glucoside stress metabolites in the cells. The active compound was fractionated using phenylalanine ammonia lyase (PAL)-inducing activity in fresh cells as a marker. The elicitor active principle appears to be a low molecular weight (<2000 MW) water-soluble acidic oligosaccharide.  相似文献   

6.
Summary InHelix pomatia L. the overlapping neuronal network was found to regulate the visceral functions (e.g. cardiorenal, respiratory and genital functions). The neural network is organized around the multifunctional interneurons, which take part in forming both afferent and efferent pathways. The interneurons are sensitive to a wide range of neurotransmitters or transmitter candidates including low molecular weight substances (ACh, 5HT, DA, octopamine, glutamate) and several oligopeptides. In this system both selection of information and modification of membrane properties (for example habituation) are carried out by a combination of simultaneously liberated active agents.  相似文献   

7.
Summary Phallolysin, a toxic hemolysin of high molecular weight, was isolated from aqueous extracts ofAmanita phalloides. Its properties are discussed.  相似文献   

8.
Metallothionein induced in the earthworm   总被引:2,自引:0,他引:2  
Summary One of the 3 different molecular weight cadmium-binding proteins induced in the earthworm was characterized as a metallothionein; this characterization was based on a high cysteine and cadmium content, low molecular weight, heatstability, and mercaptide bonding.M.Y. and K.T.S. thank Dr K. Kubota for encouragement.To whom correspondence should be addressed.  相似文献   

9.
Summary Citrate synthase has been purified to apparent homogeneity fromBacillus stearothermophilus. Its kinetic and regulatory properties, and molecular weight, are similar to those of the enzymes from suitable mesophilic counterparts, but its thermal stability is considerably greater.This work was supported by grants from the Consejo Nacional de Investigaciones Cientifficas y Técnicas de la República Argentina and the Consejo de Investigaciones de la Universidad Nacional de Rosario. AIH is a member of the Carrera del Investigador of the latter institution, and JJC is a member of the Carrera del Investigador Cientifico of the former institution.  相似文献   

10.
Summary In the brain of the honeybee (Apis mellifica), it was found that the rRNA content decreases rapidly during the first 2 days of adult life. An increase is observed from days 3 to 5, followed by another decrease to a level inferior to that of day 2 to 3. Except for a rise on the 5th day, 4s RNA remains constant. An unidentified RNA fraction of low molecular weight (D) sharply decreases on day 5. The possibility is discussed that these results reflect changes in RNA metabolism that can be related to the sequences of activity observed in the bees during the first 9 days after hatching.  相似文献   

11.
In natural squid liver, about 30% of the total Cd present was found in the cytosolic fraction. A large portion of this Cd was bound to high molecular weight species (mol. wt greater than 70,000). In contrast to Cd, about 60% of the total Ag occurred in the cytosolic fraction; Ag was bound mainly to low molecular weight species (mol. wt less than 20,000).  相似文献   

12.
Summary Aplysianin-A, an antibacterial and antineoplastic factor in the albumen gland of the sea hareAplysia kurodai, was isolated. It had a molecular weight of approximately 320 kD and consisted of subunits with a molecular weight of 85 kD. It contained 9.8% neutral sugar. Aplysianin A showed 50% inhibition ofBacillus subtilis growth at a concentration of 4 g protein/ml and 50% lysis of murine MM46 tumor cells at 14 ng protein/ml. A partial identity of antigenic specificity of the purified specimen with an antineoplastic factor fromAplysia eggs was observed in immunodiffusion tests.Acknowledgment. We are indebted to the staff of Fisheries Research Laboratory, Faculty of Agriculture, University of Tokyo, Maisaka, for the collection of sea hares.  相似文献   

13.
Summary The blue chromoproteid isolated from the fins ofCrenilabrus pavo C.V. is split by alkali hydrolysis into a protein and a pigment soluble in chloroform. The pigment is identified as biliverdin by its positive Gmelinreaction, the UV and visible absorption spectrum, and the chromatographic behaviour of its dimethyl ester. The lowest molecular weight of the chromoproteid has been evaluated from its biliverdin content to be 37,000±2400; different chromatographic fractions are presumably oligomeres of this unit.

Herrn Professor Dr.Richard Kuhn zum 65. Geburtstag gewidmet.  相似文献   

14.
In recent years the interest in antimicrobial proteins and peptides and their mode of action has been rapidly increasing due to their potential to prevent and combat microbial infections in all areas of life. A detailed knowledge about the function of such proteins is the most important requirement to consider them for future application. Our research in recent years has been focused on the low molecular weight, cysteine-rich and cationic antifungal protein PAF from Penicillium chrysogenum, which inhibits the growth of opportunistic zoo-pathogens including Aspergillus fumigatus, numerous plant-pathogenic fungi and the model organism Aspergillus nidulans. So far, the experimental results indicate that PAF elicits hyperpolarization of the plasma membrane and the activation of ion channels, followed by an increase in reactive oxygen species in the cell and the induction of an apoptosis-like phenotype. Detailed knowledge about the molecular mechanism of action of antifungal proteins such as PAF contributes to the development of new antimicrobial strategies that are urgently needed. Received 09 August 2007; received after revision 17 September 2007; accepted 19 September 2007  相似文献   

15.
Summary Aqueous extracts from spermatophores ofAcanthoscelides obtectus (Coleoptera, Bruchidae) have been chromatographed on Sephadex G 25 and G 15 columns, the active fractions being further purified by preparative SiO2 TLC. The isolation and properties of 2 biologically active compounds are reported. The paragonial substance A has a favourable action upon oogenesis, is a low molecular weight molecule (500–1000) and gives 1 single amino acid on hydrolysis, corresponding to glycin on TLC. The paragonial substance B is toxic, or an inhibitor of oogenesis at lower concentration, thus showing an antagonistic effect.  相似文献   

16.
Summary The incorporation of35S-cysteine and3H-glutamic acid was studied in mouse hepatic and renal metallothionein and in testicular cadmium-binding protein of similar molecular weight. Preferential incorporation of35S-cysteine over3H-glutamic acid was observed not only in hepatic and renal metallothionein, but also in testicular cadmium-binding protein. When the antigenic reactivity of these proteins was compared, all three proteins reacted with the metallothionein antibody. These similarities suggest that the low molecular weight testicular cadmium-binding protein is apparently metallothionein.  相似文献   

17.
Summary 3 auxin protectors, which were o-dihydroxyphenols of high molecular weight, were isolated fromZizyphus gall tissues. An increase in polyphenol oxidase activity in the gall tissue was observed which probably led to the production of high levels of auxin protectors. This prevented IAA oxidation, resulting in hyperauxinity and auxin-autotrophy.  相似文献   

18.
Summary The influence of low atmospheric pressures and low oxygen concentrations on 0-24-h-oldEphestia cautella (Wlk.) pupae at 26°C was determined. Effects on respiration, insect mortality and loss in weight obtained, were due to low oxygen tension only, at both normal and low atmospheric pressure.Contribution from the Agricultural Research Organization, Israel, No. 137-E, 1978 series.  相似文献   

19.
Summary Streptococcus pyogenes haemolyticus grown in glucose broth is capable of producing or liberating a heat-stable factor of high molecular weight which stimulates the emigration of leucocytesin vitro, only if certain animal organs are present.  相似文献   

20.
Summary In a carboxymethylcellulose-yeast extract medium,Humicola lanuginosa synthesized cellulase. The purified enzyme possessed a molecular weight of 71,000 daltons and exhibited optimum enzymatic activity at pH 5.0 and 45°C.  相似文献   

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