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PubMed1987

Metabolism of endogenous trehalose by Streptomyces griseus spores and by spores or cells of other actinomycetes.

The disaccharide trehalose is accumulated as a storage product by spores of Streptomyces griseus. Nongerminating spores used their trehalose reserves slowly when incubated in buffer for several months. In contrast, spores rapidly depleted their trehalose pools during the first hours of germination. Extracts of dormant spores contained a high specific activity of the enzyme trehalase. The level of trehalase remained relatively constant during germination or incubation in buffer. Nongerminating spores of Streptomyces viridochromogenes, Streptomyces antibioticus, and Micromonospora echinospora and nongrowing spherical cells of Arthrobacter crystallopoietes and Nocardia corallina also maintained large amounts of trehalose and active trehalase. These trehalose reserves were depleted during spore germination or outgrowth of spherical Arthrobacter and Nocardia cells into rods.

Actinomycetales↗

PubMed1988

Biochemical and genetic characterization of osmoregulatory trehalose synthesis in Escherichia coli.

It has been shown previously that Escherichia coli accumulates endogenously synthesized trehalose under osmotic stress. We report here that E. coli contained an osmotically regulated trehalose-phosphate synthase which utilized UDP-glucose and glucose 6-phosphate as substrates. In the wild type, the synthase was induced by growth in glucose-mineral medium of elevated osmotic strength and the synthase itself was strongly stimulated by K+ and other monovalent cations. A laboratory strain which expressed the synthase at a high constitutive level was found. GalU mutants, defective in synthesis of UDP-glucose, did not accumulate trehalose. Two genes governing the synthase were identified and named otsA and otsB (osmoregulatory trehalose synthesis). They mapped near 42 min in the flbB-uvrC region. Mutants with an otsA-lacZ or otsB-lacZ operon fusion displayed osmotically inducible beta-galactosidase activity; i.e., the activity was increased fivefold by growth in medium of elevated osmotic strength. Mutants unable to synthesize trehalose (galU, otsA, and otsB) were osmotically sensitive in glucose-mineral medium. But an osmotically tolerant phenotype was restored in the presence of glycine betaine, which also partially repressed the synthesis of synthase in the wild type and of beta-galactosidase in ots-lacZ fusion mutants.

Cloning, Molecular↗

PubMed1997

Stimulatory effect of trehalose on formation and activity of Escherichia coli RNA polymerase E sigma38 holoenzyme.

The intracellular concentration of trehalose increases in the stationary-phase cells of Escherichia coli. The effects of trehalose on transcription in vitro by E. coli RNA polymerase were compared for two holoenzymes, E sigma70 and E sigma38, which were reconstituted from purified core enzyme and either sigma70 (the major sigma at the exponential growth phase) or sigma38 (the essential sigma at the stationary growth phase), respectively. The optimum trehalose concentration giving maximum transcription by E sigma38 was higher than that by E sigma70. Transcription activation by trehalose was attributed to both increased formation of E sigma38 holoenzyme and increased transcription initiation by E sigma38 from sigma38-dependent promoters. The activation of E sigma38 by trehalose was additive with the transcription enhancement by decreased superhelicity of template DNA prepared from stationary-phase cells. We thus propose that the selective activation of transcription by E sigma38 holoenzyme takes place in the presence of specific conditions and factors present under stress conditions.

Coenzymes↗

PubMed1998

Trehalose is not relevant for in vivo activity of sigmaS-containing RNA polymerase in Escherichia coli.

The sigmaS- and sigma70-associated forms of RNA polymerase core enzyme (E) of Escherichia coli have very similar promoter recognition specificities in vitro. Nevertheless, the in vivo expression of many stress response genes is strongly dependent on sigmaS. Based on in vitro assays, it has recently been proposed that the disaccharide trehalose specifically stimulates the formation and activity of EsigmaS and thereby contributes to promoter selectivity (S. Kusano and A. Ishihama, J. Bacteriol. 179:3649-3654, 1997). However, we demonstrate here that a trehalose-free otsA mutant exhibits growth phase-related and osmotic induction of various sigmaS-dependent genes which is indistinguishable from that of an otherwise isogenic wild-type strain and that stationary-phase cells do not accumulate trehalose (even though the trehalose-synthesizing enzymes are induced). We conclude that in vivo trehalose does not play a role in the expression of sigmaS-dependent genes and therefore also not in sigma factor selectivity at the promoters of these genes.

Bacterial Proteins↗

PubMed1999

Biosynthesis of trehalose from maltooligosaccharides in Rhizobia.

Previously, the enzymes for trehalose synthesis that are present in Escherichia coli were demonstrated in Bradyrhizobium japonicum and B. elkanii. An alternative mechanism recently reported for the synthesis of trehalose from maltooligosaccharides was considered based on the fact that high concentrations of sugars in liquid culture stimulated the accumulation of trehalose. An assay for the synthesis of trehalose from maltooligosaccharides using crude, gel-filtered protein preparations was developed. Analysis of a variety of the Rhizobiaceae indicates that the "maltooligosaccharide mechanism" is present in B. japonicum, B. elkanii, Rhizobium sp. NGR234, Sinorhizobium meliloti, R. tropici A, R. leguminosarum bv viciae, R. I. bv trifolii, and Azorhizobium caulinodans. Synthesis of trehalose from maltooligosaccharide could not be detected in R. tropici B or R. etli.

Culture Media↗

PubMed2003

Increase of internal ion concentration triggers trehalose synthesis associated with cryptobiosis in larvae of Polypedilum vanderplanki.

Larvae of an African chironomid, Polypedilum vanderplanki, which live in temporal rock pools, are completely dehydrated when the pools dry up and undergo anhydrobiosis until the next rain comes. During the dehydration process, larvae accumulate large amounts of trehalose, which provides effective protection against desiccation because of its high capacity for water replacement and vitrification. As the occurrence of rapid trehalose synthesis coincides with loss of body water, changes of osmolarity in the body are thought to be a cue for trehalose synthesis. Indeed, exposure to high salinity triggers rapid and efficient accumulation of trehalose even without desiccation treatment. As this rapid production occurs mainly in high concentrations of salt solutions, we conclude that an increase in internal ion concentration triggers trehalose synthesis associated with cryptobiosis in this species.

Animals↗

PubMed1996

Purification and characterization of thermostable maltooligosyl trehalose trehalohydrolase from the thermoacidophilic archaebacterium Sulfolobus acidocaldarius.

A thermostable maltooligosyl trehalose trehalohydrolase from the thermoacidophilic archaebacterium Sulfolobus acidocaldarius ATCC 33909 was purified from a cell-free extract to an electrophoretically pure state by successive column chromatographies on Sepabeads FP-DA13, Butyl-Toyopearl 650M, DEAE-Toyopearl 650S, Toyopearl HW-55S and Ultrogel AcA44. The enzyme had a molecular mass of 59,000 by SDS-polyacrylamide gel electrophoresis and a pI of 6.1 by gel isoelectrofocusing. The N-terminal amino acid of the enzyme was methionine. The enzyme showed the highest activity from pH 5.5 to 6.0 and at 75 degrees C, and was stable from pH 5.5 to 9.5 and up to 85 degrees C. The activity was inhibited by Hg2+, Cu2+, Fe2+, Pb2+, and Zn2+. The Km values of the enzyme for maltosyl trehalose, maltotriosyl trehalose, maltotetraosyl trehalose, and maltopentaosyl trehalose were 16.7 mM, 2.7 mM, 3.7 mM, and 4.9 mM, respectively.

Chemical Phenomena↗

PubMedDate not supplied

Trehalose protects yeast pyrophosphatase against structural and functional damage induced by guanidinium chloride.

Trehalose is accumulated at very high concentrations in yeasts when this organism is submitted to a stress condition. This report approaches the question on the protective effect of trehalose and its degradation product, glucose, against structural and functional damage promoted by guanidinium on yeast cytosolic pyrophosphatase. Here it is shown that both, 1 M trehalose or 2 M glucose, are able to attenuate at almost the same extent the conformational changes promoted by guanidinium chloride on the pyrophosphatase structure. On the other hand while 1 M trehalose increases 3.8 times the Ki (from 0.15 to 0.57 M) for guanidinium chloride inhibition of pyrophosphatase activity, 2 M glucose did not even duplicate this parameter (from 0.15 to 0.25 M). These data support evidences for a functional reason for the accumulation by yeasts of trehalose, and not other compound, during stress conditions.

Cytosol↗

PubMed2004

Enhancement of phenanthrene solubilization and biodegradation by trehalose lipid biosurfactants.

Effects of trehalose lipid biosurfactants produced by Rhodococcus erythropolis on the solubilization and biodegradation of phenanthrene (PHE) were investigated. Based on surface tension measurements, the average critical micelle concentration (CMC) of trehalose lipids was determined to be approximately 16 mg total organic carbon (TOC)/L. In solubilization assays, the addition of biosurfactants at 20-fold the CMC increased the apparent solubility of PHE by more than 30-fold. Using a known PHE degrader (isolate P5-2), batch PHE biodegradation experiments were conducted, with and without trehalose lipids, in three systems: Water (devoid of soil solids), soil (Kenansville loamy sand having 0.72% organic matter), and soil-water slurry. Addition of trehalose lipids at 10-fold the CMC enhanced both the rate and the extent of PHE mineralization by isolate P5-2 in the liquid culture. The addition of biosurfactant (32.2 mg TOC/kg soil) to the soil system also increased both the initial rate (by more than twofold) and the extent of PHE mineralization. Biosurfactants increased the rate, but not the extent, of PHE mineralization in the soil-water slurry. The results obtained in the present study indicate that the trehalose lipid biosurfactants produced by R. erythropolis have good solubilization capacity for hydrophobic organic compounds and great potential for applications in bioremediation of sites contamination with polycyclic aromatic hydrocarbons.

Biodegradation, Environmental↗

PubMed1997

Prolongation of ischaemic tolerance of rat skeletal muscle by trehalose.

Trehalose is a disaccharide that can stabilise cell membranes under various stressful conditions. We have studied the effect of trehalose on the ischaemic tolerance of fat skeletal muscle flaps. A rat gracilis model was used to evaluate the prolongation of ischaemic preservation of the modified solution in which trehalose was substituted for glucose in Euro-Collins solution. Four groups of animals were studied. In two groups, flaps were preserved in Euro-Collins solution or trehalose Euro-Collins solution for various ischaemic intervals (6, 12, 24, 48, 72, and 96 hours). In two additional groups, after storage for various periods in the two solutions, muscle flaps were replanted into the original animals with microvascular anastomoses, and were investigated by light and electron microscopy on the seventh postoperative day. Trehalose Euro-Collins solution significantly prolonged ischaemic tolerance compared with Euro-Collins solution alone at 24 and 48 hours.

Animals↗

PubMed1990

Circadian rhythm of trehalose in the face fly Musca autumnalis de Geer.

Trehalose levels were determined over two 24 hr spans in groups of face fly adults 3-4 days after emergence from the puparium. Face fly pupae were placed in rearing chambers at 27 degrees C in a staggered light-dark regimen, LD 16:8, so that at a given clock hour, samples could be obtained at several different hours after lights on (HALO). Trehalose was determined in hemolymph collected from a puncture in the intersegmental membrane of the abdomen. Treated hemolymph samples were passed through a Bio-Rad Amino 5-S disaccharide column and a Waters 410 refractive index detector was used to differentiate among sugars. The circadian acrophase derived by cosinor analysis in hemolymph trehalose (when the values were 25.49 and 26.86 micrograms/microliters on the first and second days respectively) occurred at -226 degrees (ca 15 HALO) and the bathyphase at 24 HALO. The mesor = 11.82 micrograms/microliters trehalose, the amplitude = 8.57 micrograms/microliters trehalose and the P-value for presence of a rhythm was 0.003. Based on these data, differences between control and test flies in a bioassay of hypertrehalosemic activity would be most easily observed at 0-8 HALO, while exogenous hypotrehalosemic activity would be best assayed at 12-20 HALO.

Animals↗

PubMed1978

Tissue specific glucose-trehalose variations prior to spinning in the eri-silkworm, Philosamia ricini.

A sharp rise in trehalose level of haemolymph is observed towards the end of 4th instar accompanied with sudden fall of the sugar in fat body during the same period, but after moulting blood trehalose abruptly decreases. Whereas, blood glucose level is maintained constant throughout life span of both the instars. Silkgland of 5th instar larvae presents a consistent gradual increase in glucose-trehalose levels reaching to the maximum prior to spinning with a higher value for trehalose than glucose which can be attributed to the decrease in blood trehalose level during the period.

Age Factors↗

PubMedDate not supplied

Hypoglycaemic activity of alpha, alpha trehalose-6-phosphate.

Alpha-alpha-trehalose-6-phosphate, synthesized by Oke was screened for hypoglycaemic activity. Alloxan-induced diabetic albino rats and fasted-rabbits were used in the study. The inhibitory activity of trehalose-6-phosphate on trehalase was also assayed. The study shows that alpha-alpha-trehalose-6-phosphate is a glucose analogue with potent anti-hyperglcaemic activity as shown by its hypoglycaemic response in fasted rabbits. The ability of alpha-alpha-trehalose-6-phosphate to attenuate the diabetic toxicity in alloxan-induced diabetic rats confirmed its potent anti-diabetic activity. The mechanism of action of this synthesized compound may be linked with its ability to inhibit trehalase, and increase the activity of the superoxidase dimutase present in the beta-cells of the alloxan-diabetic rats and also being a glucose analogue according to Puls principle, alpha-alpha-trehalose-6-phosphate is able to influence the intermediate metabolism of carbohydrate.

Administration, Oral↗

PubMed1975

Trehalose and glycogen levels during the initial stages of growth of Candida albicans.

Yeast phase cells of Candida albicans were extracted with cold 0.5 M trichloroacetic acid. The only quantitatively significant anthrone-positive material in these extracts was trehalose which was identified chromatographically and enzymatically. Glycogen in the residue was digested with amyloglucosidase to free glucose which was assayed by a glucose oxidase method. Washed cells from a stationary phase culture of C. albicans rapidly decreased their trehalose content during the early phases of growth on a fresh glucose-containing medium. Concurrent increases in total glycogen concentration were of a greater magnitude than could be accounted for by trehalose mobilization. Thus a specific role for trehalose during initial growth is indicated and is compared with other fungal systems. Trehalase activity was measured in situ and showed only minor changes during the time intervals of these experiments in contrast to other reports on S. cerevisiae. A large fraction of the enzyme in C. albicans behaved as external to the protoplasmic membrane. On one type of growth medium C. albicans exhibited (in addition to trehalose) variable amounts of a sugar alcohol in trichloroacetic acid extracts. This has tentatively been identified as arabitol.

Candida albicans↗

PubMed2002

[Study on the production of trehalose by bacterium D-97 endocellular enzymes using HPLC/RI and HPLC/ESI-MS].

The mechanism in which trehalose is produced from dextrin or starch hydrolyzate by endocellular enzymes of bacterium D-97 can be elucidated high performance liquid chromatography (HPLC) with differential refraction detection (RI) basically, including the effect of the different carbon sources on the endocellular trehalose-producing enzymes in bacterium D-97 and the possibility or ability of the endocellular enzymes to produce trehalose using maltooligosaccharides of different chain lengths. After purification of endocellular enzymes of bacterium D-97, two enzymes (called Enzyme A and Enzyme B) related to trehalose synthesis were found. The unknown oligosaccharides produced by Enzyme A were analyzed with the HPLC/RI and HPLC/ESI-MS (electrospray ionization mass spectrometry). The results showed the relative molecular masses of the unknown oligosaccharides were the same as those of the enzymatic reaction substances (maltotriose, maltotetraose and maltopentaose) respectively. In combining with other results of biological experiments, these unknown oligosaccharides had been identified basically. There was no reduction power in these unknown oligosaccharides and only one trehalose residue exited in the molecular chain of these unknown oligosaccharides.

Bacteria↗

PubMed2005

[Cold storage of platelet suspension by adding trehalose].

The study was aimed to explore the trehalose method for storing platelets in cold. (51)Cr-labeling platelet was used to detect the platelet survival. The platelet function in vitro was performed by platelet aggregate analyzer. After treatment with 50 mg/ml trehalose at 37 degrees C for 4 hours, the rabbit platelet concentrates (PC, 2.0 x 10(9)/ml) were stored in 4-8 degrees C refrigeration, the platelet function in vitro and survival of chilled platelets transfused into self-rabbits were observed. The results showed that trehalose could protect the chilled rabbit platelets. After PC stored at 20-24 degrees C and 4-8 degrees C for up to 24 hours, the platelet aggregate in vitro in response to 11.2 micromol/L ADP were (75.3 +/- 9.8)% and (80.5 +/- 12.5)%, the survival of PC stored at 20-24 degrees C and 4-8 degrees C for 24, 48, 72 hours after transfused into self-rabbits were (78.1 +/- 7.9)%, (65.4 +/- 6.7)%, (57.5 +/- 7.2)% and (5.1 +/- 2.5)%, (2.8 +/- 2.0)%, (0.9 +/- 0.8)%, respectively. The PC treated with 50 mg/ml trehalose were remained stable for up to 12 days of refrigerated storage in autologous plasma. The platelet aggregate in vitro in response to 11.2 micromol/L ADP at 12 days after stored in refrigeration was (77.8 +/- 9.5)%, the survival on 24, 48, 72 hours of platelet transfused into self-rabbits were (75.7 +/- 11.0)%, (67.0 +/- 8.5)%, (56.8 +/- 8.0)%, respectively. Compared with control group of storing at 20-24 degrees C for 24 h, P > 0.05. In conclusion, trehalose can protect the chilled blood platelets, prolong the circulation of refrigerated rabbit platelets, and not impair chilled rabbit platelet function.

Adenosine Diphosphate↗

PubMedDate not supplied

[Comparative analysis of glycogen and trehalose accumulation in methylotrophic and nonmethylotrophic yeasts].

Trehalose and glycogen accumulate in certain yeast species when they are exposed to unfavorable growth conditions. Accumulations of these reserve carbohydrates in yeasts provide resistance to stress conditions. The results of this study indicate that certain Pichia species do not accumulate high levels of glycogen and trehalose under normal growth conditions. However, depending on the Pichia species, both saccharides accumulate at high levels when the Pichia cells are exposed to unfavorable or stress-inducing growth conditions. Growth on glycerol or methanol mostly led to trehalose accumulation in Pichia species tested in this study. It was shown that the metabolic pathways for glycogen and trehalose biosynthesis are present in Pichia species. However, it appears that the biosynthesis of trehalose and glycogen may be regulated in different manners in Pichia species than in the yeast S. cerevisiae.

Culture Media↗

PubMed1991

On the role of trehalose in yeast cells subjected to hypersomotic shock.

Plate counts on both high and low water activity (aw) media were performed during the growth of Candida utilis in batch culture. The results revealed a marked discrepancy between the counts on the two media in the logarithmic phase. The discrepancy almost disappeared in stationary phase revealing a higher resistance of these cells, as compared to growing cells, to the severe dehydration imposed by the hyperosmotic shock upon transfer to low aw medium. Since the two types of cells differ in the level of endogenous trehalose the relation between plating discrepancy and trehalose content of the cells was investigated. Treatments that changed the intracellular trehalose concentration did not modify the plate counts on low aw medium. It was therefore concluded that the amount of trehalose into the cells is not the only factor conferring resistance against the hyperosmotic shock. Glycerol content did not correlate with resistance to the water stress either. Congruent with the former conclusion, other yeast species (Sporobolomyces salmonicolor, Schizosaccharomyces pombe) showed no correlation between changes in the trehalose content and susceptibility or resistance to the osmotic stress in low aw medium.

Candida↗