Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Trehalose”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 919 records · Page 51Linked to original sources

Preparation of 3-amino-3-deoxy derivatives of trehalose and sucrose and their activities.

The 3-keto derivatives of trehalose and sucrose respectively were prepared by a one-step enzymatic route using D-glucoside 3-dehydrogenase from Flavobacterium saccharophilum. Reductive amination of 3-ketotrehalose with ammonium acetate and sodium cyanoborohydride gave three compounds, 3-amino-3-deoxy-alpha-D-allopyranosyl alpha-D-glucopyranoside, 3-amino-3-deoxy-alpha-D-glucopyranosyl alpha-D-glucopyranoside (3-trehalosamine) and 3-amino-3-deoxy-alpha-D-mannopyranosyl alpha-D-glucopyranoside. From the reductive amination of 3-ketosucrose, 3-amino-3-deoxy-alpha-D-allopyranosyl beta-D-fructofuranoside and 3-amino-3-deoxy-alpha-D-glucopyranosyl beta-D-fructofuranoside were obtained. The antibiotic and glycohydrolase inhibitory activities of these 3-amino-3-deoxy derivatives were determined.

Amination↗

Temperature dependence of the rotational mobility of the sugar and water molecules in concentrated aqueous trehalose and sucrose solutions.

Carbon-13 and deuteron spin lattice relaxation times T1 of concentrated solutions of trehalose and sucrose in heavy water are given as function of temperature. From the temperature dependence of the T1 ideal glass transitions temperatures T0 are derived. For both compounds the T0 derived for the disaccharides are at high concentrations larger than the T0 of the water molecules.

Calorimetry↗

Derivatives of glutamic acid and trehalose which can be transformed into long-living free radicals by the loss of an electron are identified in some bacteria.

A derivative of glutamic acid (ammonigenin) and a trisaccharide named lysodektose which are converted into long-living free radicals by the loss of one electron were isolated from Brevibacterium ammoniagenes and Micrococcus lysodeikticus. Structural formulae suggested for both substances based on ESR-, NMR- and mass spectra, isotopic substitution experiments and other data are: lactone of N-hydroxy-N-(2-carbamoylethyl)-glutamyl-4-amino-2-hydroxybutyric amide and 6-O-[2-deoxy-2-(N-methyl)-hydroxylamino-beta-D-glucopyranosyl]- alpha, alpha-trehalose. Radical forms appear on reversible oxidation of hydroxylamino groups to nitroxyl groups. Participation in the protection of bacterial cells and regulation of their metabolism is suggested for these compounds.

Bacteria↗

Antitumor effect of a synthetic cord factor, 6,6'-di-O-decanoyl-alpha,alpha-trehalose (SS554), in mice.

The antitumor effect on Meth-A fibrosarcoma in BALB/c mice of a synthetic cord factor, 6,6'-di-O-decanoyl-alpha,alpha-trehalose (designated as SS554), was examined. Only intratumoral injection had a curative effect; subcutaneous, per oral, or intravenous routes had no such effect. The co-presence of an oily vehicle has been shown to be necessary for antitumor activity of a natural cord factor. When SS554 was examined in suspensions of sesame oil, squalane, squalene or sesame oil and water emulsion, a 60% cure rate was achieved. However, no such effect was obtained with a suspension in Tween-PBS or a solution. It should also be noted that sequential but independent administrations of SS554 and oil were found to be as effective as the simultaneous administration of oil and SS554 in emulsion form. In the case of the emulsion, the amount of sesame oil necessary was over 10%, or 0.01 ml in absolute terms. Cures were obtained in a dose-dependent manner by injection of SS554 in amounts in excess of 1 mg. The effect of the time of administration was also examined; the best result was obtained when intratumoral injection was done on day 3 after tumor implantation. Mice cured by SS554 exhibited growth inhibition and rejection of rechallenged Meth-A cells. However, this immunity was specific; it did not extend to a rechallenge with RLmale-1 leukemia cells.

Animals↗

[Antitumor effect of a synthetic cord factor, 6,6'-di-O-decanoyl-alpha, alpha-trehalose (SS 554) in mice].

The antitumor effect of a synthetic cord factor (6, 6'-Di-O-decanoyl-alpha, alpha-trehalose) (SS 554) on the growth of Meth-A fibrosarcoma in BALB/c mice was examined. With regard to administration routes, only intratumoral (i.t.) injection showed a curative effect; subcutaneous (s.c.), per oral (p.o.) or intravenous (i.v.) routes has no such effect. To show the antitumor effect of known natural and synthetic cord factors, the co-presence of oily vehicles has been shown to be necessary. Accordingly, compound SS 554 examined in suspensions of sesame oil, squalane (SQA), squalene (SQE) or sesame oil and water emulsion had a curative effect with a 60% survival rate. However, no such effect was obtained with a suspension in PBS or in HCO-60 solution. In this regard, it should be noted that sequential but independent administration of SS 554 and oil was found to be equally as effective as simultaneous administration of oil with SS 554. Thus the effect of the oil should be reconsidered through an examination of the sequential appearance of effector cells. In the case of sesame oil, the amount of oil necessary was over 10%, or 0.01 mg absolutely. When the dose effect of SS 554 was examined in the presence of 10% sesame oil, doses over 1 mg exhibited a dose dependent curative effect. In tumor-bearing mice, the effect of the time of administration was also examined; the best result was obtained when intratumor injection was performed on day 3 after tumor implantation. Mice that recovered after SS 554 treatment exhibited growth inhibition and rejection of rechallenged Meth-A cells. However, this immunity was specific as it did not extend to a rechallenge with RL male-1 leukemia cells.

Animals↗

A study of trehalase (EC 3.2.1.28) and trehalose in relation to aging in Callosobruchus analis.

Trehalase (EC. 3.2.1.28) activity has been studied during aging in male and female Callosobruchus analis beetles. Enzyme activity was much higher in females than males throughout adult life. Trehalase showed two peaks of activity in females, a small peak on the 3rd day and another on the 10th day after adult ecdysis, while males showed one peak only on the 10th day after emergence. Besides trehalase activity, trehalose as a percentage of total sugars, and mortality curves have been studied. It was found that the energy needs of the insects also increase as they age.

Aging↗

Trehalose-containing lipooligosaccharides. A new class of species-specific antigens from Mycobacterium.

Mycobacterium kansasii is characterized by the presence of seven species-specific neutral lipooligosaccharide antigens. All react with hyperimmune anti-M. kansasii serum in enzyme-linked immunosorbent assays, and the more glycosylated members also react by gel diffusion. Both the native glycolipids and their inherent oligosaccharides were purified and the major features of their unique structures determined by acetolysis, partial acid cleavage, 1H-NMR and 13C-NMR, and chemical ionization and electron impact mass spectrometry of the permethylated products. They have in common a tetraglucose "core," beta-D-Glcp-(1 leads to 3)-beta-D-Glcp-(1 leads to 4)- alpha-D-Glcp(1 leads to 1)-alpha-D-Glcp where Glcp is glucopyranose, distinguished by the presence of an alpha,alpha-trehalose substituent. Variable residues of xylose, 3-O-methylrhamnose, fucose, and a novel N-acyl aminosugar, (4,6-dideoxy-2-O-methyl-3-C-methyl-4-(2'-methoxypropionamido)hexose; proof of this structure is not given) are linked to the core and the resulting oligosaccharides are acylated with 2,4-dimethyltetradecanoyl and acetyl functions to present a familial arrangement. Related but species-specific lipooligosaccharides typify Mycobacterium szulgai and apparently a host of other atypical mycobacteria. Thus, the antigenicity, and perhaps other features such as pathogenesis and drug resistance, of most atypical mycobacteria may be rationalized in terms of these new found cell wall lipooligosaccharides and the previously described glycopeptidolipids.

Antigens, Bacterial↗

N-acylkansosamine. A novel N-acylamino sugar from the trehalose-containing lipooligosaccharide antigens of Mycobacterium kansasii.

A novel N-acylamino sugar was isolated from the antigenic trehalose-containing lipooligosaccharides IV-VII of Mycobacterium kansasii. The native reducing sugar, its O-acetyl derivative, the methylglycoside, the O-acetylated alditol, and the de-N-acylated N-, O-acetylated alditol were all examined by high resolution 1H NMR, 13C NMR, direct probe and gas-liquid chromatography-mass spectrometry in both the chemical ionization and electron impact modes, and by high resolution mass spectrometry. The dideoxy sugar had a formula weight of 277, an empirical formula of C12H23NO6, C- and O-methyl substituents, and a N-methoxypropionyl branch. Upon alkaline hydrolysis, methoxypropionic acid was released and shown to correspond to the synthetic compound by gas chromatography and chemical ionization and electron impact mass spectrometry. The structure 4,6-dideoxy-2-O-methyl-3-C-methyl-4-(2'-methoxypropionamido)-alpha and beta-L-manno-hexopyranose, with the trivial name N-acylkansosamine, is proposed. The sugar is present in the more polar, highly antigenic lipooligosaccharides and is regarded as exclusive to M. kansasii and as its primary cell wall immunodeterminant.

Amino Sugars↗

[Antitumor effect of synthetic cord factor analogue, 6, 6'-Di-O-decanoyl-alpha, alpha-trehalose].

The antitumor effect of a new synthetic cord factor analogue, 6, 6'-Di-O-dacanoyl-alpha, alpha-trehalose (SS 554), was examined in vivo and in vitro. Remarkable life prolongation effects were observed after the intraperitoneal administration of SS554 at a dosage of 150 mg/kg in mice implanted with Ehrlich ascitic tumor cells. Using in vitro tests, the growth of various tumor cell lines i.e. Meth-A, EL-4, RL male-1, X5563, Raji and Jurkat were inhibited by SS554 at a 25 mcg/ml concentration. The mechanism of the direct antitumor activity of SS554 was studied using these tumor cell lines and bacterial cells. After treatment with SS554 at a 50 mcg/ml dose for 30 minutes, tumor cells and bacterial protoplasts but not intact bacterial cells were destroyed, indicating that SS554 causes the lysis of the membranes of these cells.

Animals↗

Stabilisation of vaccines using trehalose (Q-T4) technology.

Efforts directed towards overcoming the problems of vaccine stability must take cost into consideration. One effective approach is the use of a simple stabilization technology applicable, in principle, to every type of vaccine candidate. Following the lead of Nature, the results in this paper show how such techniques based on trehalose have the potential to transform contemporary vaccine manufacture. The possibilities of novel delivery formats and vaccine combinations, currently not feasible, may now also be realised.

Adjuvants, Immunologic↗

Macrophage activation by trehalose dimycolate requirement for an expression signal in vitro for antitumoral activity; biochemical markers distinguishing primed and fully activated macrophages.

It was possible to define the effects of trehalose dimycolate (TDM), a glycolipid extracted from Mycobacterium tuberculosis, on mouse peritoneal macrophages more precisely using endotoxin-free culture conditions. TDM-elicited macrophages, when assayed in vitro in the absence of endotoxin, were unable to limit tumor growth; however, after a short treatment (4 h) with low doses of lipopolysaccharide (LPS; 1-10 ng/ml), they exhibited a strong cytostatic capacity against P815 mastocytoma cells. Thus, TDM injected in vivo did not activate macrophages fully but it primed them to respond in vitro to low doses of LPS, which provided the final stimulus for activation to antitumor competence. Macrophages elicited by an injection of killed group C Streptococci were also in a primed state; in contrast, thioglycollate-elicited macrophages were in a nonreceptive state. Besides LPS, concanavalin A (5 micrograms/ml), MDP (0.2-1 microgram/ml) and the ionophore A23187 (5 microM) can deliver the activation signal to TDM-primed macrophages. Primed macrophages were found to express several biochemical markers previously described as specific for activated macrophages (low levels of alkaline phosphodiesterase and beta-galactosidase, for example) and, although they were not cytotoxic for tumor cells, they had the capacity to release large amounts of H2O2. However, when pulsed by LPS or MDP, primed macrophages responded by further modifications in their metabolism: the rate of glucose consumption and the labeling of glycoproteins by D-[2-3H]mannose were greatly increased and the secretion of a polypeptide of 22 kDa was enhanced. The activation-associated biochemical markers are thus acquired in two steps. The ability to produce activated oxygen species is expressed earlier than the antitumoral activity.

Animals↗

Separating structure and dynamics in CSA/DD cross-correlated relaxation: a case study on trehalose and ubiquitin.

We present two new sensitivity enhanced gradient NMR experiments for measuring interference effects between chemical shift anisotropy (CSA) and dipolar coupling interactions in a scalar coupled two-spin system in both the laboratory and rotating frames. We apply these methods for quantitative measurement of longitudinal and transverse cross-correlation rates involving interference of (13)C CSA and (13)C-(1)H dipolar coupling in a disaccharide, alpha,alpha-D-trehalose, at natural abundance of (13)C as well as interference of amide (15)N CSA and (15)N-(1)H dipolar coupling in uniformly (15)N-labeled ubiquitin. We demonstrate that the standard heteronuclear T(1), T(2), and steady-state NOE autocorrelation experiments augmented by cross-correlation measurements provide sufficient experimental data to quantitatively separate the structural and dynamic contributions to these relaxation rates when the simplifying assumptions of isotropic overall tumbling and an axially symmetric chemical shift tensor are valid.

Journal Article↗

Modulation of natural killer cytotoxicity by muramyl dipeptide and trehalose dimycolate incorporated in squalane droplets.

The effect on natural killer (NK) cytotoxicity of splenic cells from BALB/c mice pretreated i.v. with squalane-in-water preparations of muramyl dipeptide (MDP), trehalose dimycolate (TDM), or the combination of MDP-plus-TDM was investigated. MDP or TDM augmented the NK cytotoxicity which peaked 48 h after the pretreatment whereas the combination of MDP and TDM induced an inhibition of the NK activity. Infection with influenza virus, a potent stimulator of NK cells, after the pretreatment with biological response modifiers resulted in a markedly enhanced NK activity on day 2 in MDP and control groups. Mice pretreated with TDM or the combination of MDP and TDM showed only moderate NK activity which peaked on day 3 after influenza infection. The NK activity was susceptible to asialo GM1 and complement treatment. The cytotoxicity of MDP-plus-TDM cells could be significantly enhanced after treatment with anti-macrophage monoclonal antibody and complement. NK activity induced by MDP or TDM was reduced by mixing MDP-plus-TDM cells. Addition of adherent cell-depleted MDP-plus-TDM suspension to MDP or TDM cells had a NK restorative effect. Splenic cells from mice pretreated 2 days earlier with MDP or TDM, but not MDP-plus-TDM, generated enhanced levels of luminol-dependent chemiluminescence.

Acetylmuramyl-Alanyl-Isoglutamine↗

Activation of rat alveolar macrophages and protection against i.v. injected tumor cells by intratracheal administration of trehalose dimycolate.

Intratracheal (i.t.) administration of trehalose dimycolate (TDM) in saline as liposomes induces a transient inflammatory effect. Limited granulomas appeared in some peribronchial areas but most subsided after a few weeks. The alveolar macrophages were activated as judged by their cytostatic activity against the syngeneic P77 fibrohistiocytoma 3 days after administration of 0.2 mg TDM. The NK activity of the lymphocytes of the lung microcirculation did not increase and diminished slightly between 1 and 3 days after TDM administration, thus suggesting that macrophages might be the main effector cells responding to TDM. Repeated i.t. TDM administration protected rats against the development of colonies in the lung after i.v. injection of 5 X 10(5) P77 cells. The survival of the rats was significantly increased. Thus, in this system, a relationship exists between activation of alveolar macrophages and protection against colonies arising from i.v. injected tumor cells.

Animals↗

Immunogold localization of trehalose-6-phosphate synthase in leaf segments of wild-type and transgenic tobacco plants expressing the AtTPS1 gene from Arabidopsis thaliana.

Following the establishment of a transgenic line of tobacco (B5H) expressing the trehalose-6-phosphate synthase (TPS) gene from Arabidopsis thaliana, a preliminary immunolocalization study was conducted using leaves of adequately watered B5H and wild-type plants. Immunocytochemical staining, followed by electron microscopy showed that the enzyme could be detected in both B5H and wild-type plants at two different levels. Quantification showed the signal to be two to three times higher in transgenic plants than in the wild type. This enzyme was markedly present in the vacuoles and the cell wall, and to a lesser extent in the cytosol. Moreover, a high profusion of gold particles was detected in adjacent cells and in the sieve elements. Occasional spots were also detected in chloroplasts and the nucleus, especially in the transgenic B5H line. No labeling signal was detected in mitochondria. Protein localization seems to confirm the important role of TPS in sugar metabolism and transport through the plant, which could explain its role in plant stress tolerance. Finally, it can be expected that TPS from tobacco has a relatively high similarity to the TPS of Arabidopsis thaliana.

Arabidopsis↗

Interaction of cord factor (alpha, alpha'-trehalose-6,6'-dimycolate) with phospholipids.

We previously reported that cord factor (alpha,alpha'-trehalose-6,6'-dimycolate) isolated from Nocardia asteroides strain GUH-2 strongly inhibits fusion between unilamellar vesicles containing acidic phospholipid. We chose to study the effects of this molecule on liposome fusion since the presence of N. asteroides GUH-2 in the phagosomes of mouse macrophages had been shown to prevent phagosomal acidification and inhibit phagosome-lysosome fusion. A virtually non-virulent strain, N. asteroides 10905, does not prevent acidification or phagosome-lysosome fusion and, further, contains only trace amounts of cord factor. In the present paper, we have investigated the effects of cord factor on phospholipid bilayers that could be responsible for the inhibition of fusion. We show that cord factor increases molecular area, measured by isothermal compression of a monolayer film, in a mixed monolayer more than would be expected based in its individual contribution to molecular area. Cord factor, as well as other glycolipids investigated, increased the overall hydration of bilayers of dipalmitoylphosphatidylcholine by 50%, as estimated from the unfrozen water fraction measured by differential scanning calorimetry. The effect of calcium on this increased molecular area and headgroup hydration was measured by fluorescence anisotropy and FTIR spectroscopy of phosphatidylserine liposomes. Both techniques showed that cord factor, incorporated at 10 mol%, increased acyl chain disorder over controls in the presence of Ca2+. However, FTIR showed that cord factor did not prevent headgroup dehydration by the Ca2+. The other glycolipids tested did not prevent either the Ca(2+)-induced chain crystallization or headgroup dehydration of phosphatidylserine bilayers. These data point to a possible role of the bulky mycolic acids of cord factor in preventing Ca(2+)-induced fusion of liposomes containing acidic phospholipids.

1,2-Dipalmitoylphosphatidylcholine↗

Synthesis and immunoadjuvant activity of 2,2'-O-[2,2'-diacetamido-2,3,2',3'-tetradeoxy-6,6'-di-O-(2-tetradecyl- hexadecanoyl)-alpha,alpha'-trehalose-3,3'-diyl]bis(N-D-lactoyl-L-alanyl -D-isoglutamine).

The disaccharide of 6-O-(2-tetradecylhexadecanoyl)muramoyl dipeptide coupled through an alpha-(1----1)-alpha linkage, named in the title, and an analog bearing a single peptide moiety, have been synthesized from 2,2'-diazido-2,2'-dideoxy-alpha,alpha'-trehalose. The immunoadjuvant activities of the products were examined.

Acetylmuramyl-Alanyl-Isoglutamine↗

Effect of low mole fraction of trehalose dicorynomycolate from Corynebacterium diphtheriae on water permeability and electrical capacitance of lipid bilayer membranes.

The effect of incorporation of different proportions of trehalose dicorynomycolates (TDC) into lecithin bilayer membranes was studied. It was found that TDC, induces a 14% decrease of water osmotic permeability (42.6 +/- 3.9 to 36.8 +/- 2.7 microns/s) at 1.6 mole%, suggesting that this substance leads to an increase of the degree of packing of the constituent lipid molecules. A condensing effect of TDC was also apparent from membrane electrical capacitance (Cm) measurement. By incorporating TDC into bilayer membranes, the value of Cm experienced a decrease of 29% at 1.6% mole fraction. This finding was taken to reflect an increase in membrane thickness, known in many examples, to be related to the condensing effect.

Cord Factors↗