Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Trehalase”

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 235 records · Page 13Linked to original sources
PubMed1995

Trehalase activity and trehalose content in a freeze-tolerant yeast, Torulaspora delbrueckii, and its freeze-sensitive mutant.

Two types of trehalase activities different in the optimum reaction pH (4.3 and 6.7) were found in a freeze-tolerant yeast, Torulaspora delbrueckii D2-4, and three types of the activities at pH 4.3, 5.7, and 6.7 were found in its freeze-sensitive mutant (60B3). The pH 4.3 activities in the cell extracts of the two strains were on the same level, but the pH 6.7 activity in the strain D2-4 was about half of that in the strain 60B3. The enzyme with the pH 4.3 activity and the other two enzymes were analogous to acid and neutral trehalases, respectively, in the sensitivity to metal ions and in response to phosphorylation and dephosphorylation. The trehalose content in the strain D2-4 was three times higher than that in the strain 60B3. The change of trehalose content during growth of the strain 60B3 correlated only to the change of the pH 5.7 activity.

Adaptation, Physiological↗
PubMed2001

Purification and identification of the essential ionizable groups of honeybee, Apis mellifera L., trehalase.

Trehalase (EC 3.2.1.28) of the bound type was purified as an electrophoretically homogeneous protein from adult honeybees by fractionation with ammonium sulfate, hydrophobic chromatography, and DEAE-Sepharose CL-6B, CM-Sepharose CL-6B, butyl-Toyopearl 650M, and p-aminophenyl beta-glucoside Sepharose 4B column chromatographies. The enzyme preparation was confirmed to be a monomeric protein containing 3.1% carbohydrate. The molecular weight was estimated to be approximately 69,000, and the optimum pH was 6.7. The Michaelis constant (Km) was 0.66 mM, and the molecular activity (k0) was 86.2 s(-1). The enzyme was an "inverting" type which produced beta-glucose from alpha, alpha-trehalose. Dependence of the V and Km values on pH gave values for the ionization constants, pKe1 and pKe2, of essential ionizable groups 1 and 2 of the free enzyme of 5.3 and 8.5, respectively. When the dielectric constant of the reaction mixture was decreased, pKe1, and pKe2 were shifted to higher values of + 0.2 and + 0.5 pH unit, respectively. The ionization heat (deltaH) of ionizable group 1 was estimated to be + 1.8 kcal/mol, and the deltaH value of group 2 was + 1.5 kcal/mol. These findings strongly support the notion that the essential ionizable groups of honeybee trehalase are two kinds of carboxyl groups, one being a dissociated type (-COO(-), ionizable group 1) and the other a protonated type (-COOH, ionizable group 2), although the pKe2 value is high.

Animals↗
PubMed2001

Effect of estradiol-17beta on cell area, lumen area and trehalase activity of posterior silk gland of Bombyx mori L.

Estradiol-17beta (E2) at the dose of 1 microg/g caused an increase in cell area, lumen area and the total (cell + lumen) area of posterior silk gland (PSG) in Bombyx mori indicating that exogenously applied estradiol-17beta has a regulatory influence on silk gland activity. A dose-dependent variation in trehalase activity of PSG was found on the 5th day after topical administration of estradiol on 1st and 2nd day of the fifth larval instar. Of all the doses of E2 used, 1 microg/g dose had maximum stimulatory effect on trehalase activity. Co-administration of each of a specific receptor antagonist for estradiol, the ICI-182780 and a protein biosynthetic blocker, cycloheximide with E2 suppressed the E2-induced increase in silk gland activity. The results suggest some specific metabolic action of E2 on silk gland and offer a promising way for future investigations regarding the physiological significance of vertebrate steroids in insects.

Animals↗
PubMed1992

Characterization of trehalase in Rhodotorula rubra.

Trehalase activity in Rhodotorula rubra was found to be bound to the particulate fraction of a cell-free extract in contrast with the soluble trehalase activity of Saccharomyces cerevisiae. The enzyme was strongly repressed by glucose and derepressed during growth on maltose, trehalose and glycerol. This increase in activity was due to a "de novo" synthesis as seen by inhibition with cycloheximide, a mechanism not described for Saccharomyces cerevisiae. Catabolite inactivation by addition of glucose was also demonstrated. This particulate enzyme does not respond to activation by the cAMP-dependent protein kinase.

Cycloheximide↗
PubMed2005

[Cloning and characterization of the neutral trehalase gene in Metarhizium anisopliae CQMa102].

The partial fragment of the neutral trehalase (NTL) in Metarhizium anisopliae CQMa102 was amplified by the polymerase chain reaction (PCR) with primers designed according to the sequences of the NTL in GenBank. The amplified fragment was cloned and sequenced. Based on the known sequence of NTL gene, the 5' and 3' rapid amplification of cDNA ends (RACE) were used to amplify the 5' and 3'regions of the NTL cDNA, then the whole cDNA sequence of NTL gene in M. anisopliae CQMa102 was obtained by combining the above sequences and its whole genomic DNA was amplified by PCR. In order to obtain more regulatory information of the NTL, panhandle polymerase chain reaction strategy was used to amplify the 5' flanking sequences adjacent to the known sequence of the neutral trehalase gene. The sequence analysis shows that the DNA sequence is 3484bp in size, includes three introns, and the cDNA sequence is 2385 bp in size, encodes a protein of 737 amino acid residues with a calculated Mr of 83.1kD, in which there is a cyclic adenosine 3', 5'-monophosphate-dependent phosphorylation consensus site and a putative calcium binding site, which is consistent with a regulatory enzyme. Comparison of this sequence with the NTL of M. anisopliae ME1 in GenBank (GenBank Accession: AJ298019, AJ298020) shows that the nucleotide homology is as high as 93%, and the amino acid homology comes up to 99%. Southern analysis indicated that NTL gene was present as a single copy in this M. anisopliae strain. A single transcript of approximately 2.5 kb was detected by Northern blot analysis. The NTL mRNA was present throughout spore germination in rich medium, but accumulated to its highest level at the early stage of exponential growth. Thereafter, the mRNA level declined at the late stage of exponential growth, but began to show an increase during the stationary phase of growth. A 982bp upstream sequence of NTL was amplified using panhandle PCR method, which contains one stress response element (STRE). The NTL nucleotide sequence and its amino acid sequence have been accessed by GenBank (Accession: AY557613, AY557612).

Animals↗
PubMed2006

Content of glycogen and trehalose and activity of alpha-amylase and trehalase in Galleria mellonella larvae infected with entomopathogenic nematodes Steinernema affinis and S. feltiae.

INTRODUCTION: The influence of infection with two species of entomopathogenic nematodes of Steinernematidae family on metabolism of glycogen and trehalose of the host was studied. MATERIAL AND METHODS: Last instar larvae (L7) of Galleria mellonella were experimentally infected with Steinernema affinis and S. feltiae. At 6, 12, 18 and 24 h after infection concentrations of trehalose and glycogen as well as activity of trehalase and alpha-amylase were determined. RESULTS: The content of glycogen was lower in insects infected with S. feltiae than in the controls and animals infected with S. affinis. The content of trehalose was higher in insects from both infected groups than in the controls. Its concentration was slightly higher in larvae infected with S. affinis than in those infected with S. feltiae. The activity of alpha-amylase after infection with S. affinis was low. It was significantly higher in insects infected with S. feltiae. In animals of both infected groups, following a significant reduction at 6 h, the activity of trehalase remained at a similar level, higher than in the controls. In the paper the effects of infection with (i) different species of entomopathogenic nematodes and (ii) the importance of the developmental stage of the insect-host for changes in its metabolism of glycogen and trehalose were discussed.

Animals↗
PubMed1989

Purification and characterization of trehalase inhibitor from hemolymph of the American cockroach, Periplaneta americana.

An endogenous proteinaceous inhibitor of trehalase (alpha,alpha-trehalose-1-glucohydrolase: EC 3.2.1.28) has been isolated and purified from the serum of resting adult American cockroaches, Periplaneta americana. Purification procedures involved decreasing ionic strength, gel filtration, and reversed phase high performance liquid chromatography. Homogeneity was confirmed by polyacrylamide gel electrophoresis and end group analysis. The purified protein inhibited trehalase activity in a dose-dependent manner and was estimated to have a molecular weight of 86,000 and to contain sugar chains. An automated gas-phase sequencer was used to determine the following sequence for the N-terminal amino acid residues: H-Ala-Ilu-Pro-Thr-Pro-His-Val-Tyr-Lys-Val-X-Val-Pro-Asp-Gly-Ala-Le u-Asn-Asp.

Amino Acid Sequence↗
PubMed1987

Inhibition by alpha factor of the glucose-induced activation of regulatory trehalase in Saccharomyces cerevisiae.

The enzyme activity of the regulatory trehalase (alpha, alpha-trehalose glycohydrolase; EC 3.2.1.28) in stationary-phase cells of Saccharomyces cerevisiae increased upon addition of glucose to cell suspensions. Such increase was temporarily retarded in the presence of alpha factor in the medium. The transient inhibition required the joined action of the pheromone-like factor and the protease inhibitor N-alpha-p-tosyl-L-lysine chloromethyl ketone. The inhibition of the glucose-induced activation of trehalase by alpha factor lends support to the involvement of adenosine 3',5'-cyclic monophosphate in the enzyme activation in vivo.

Cell Division↗
PubMed1979

Two forms of trehalase activity in mice.

Trehalase activities from mouse serum and kidney have been compared on ion exchange chromatography (DEAE-cellulose and SP-Sephadex). The two activities showed a distinct behaviour. This was confirmed by polyacrylamide gel electrophoresis and thermal lability, suggesting the presence of at least two forms of the hydrolytic enzyme trehalase in mice.

Animals↗
PubMed1994

Periplasmic trehalase from Escherichia coli--characterization and immobilization on spherisorb.

1. Trehalase was partially purified from Escherichia coli and characterized. The Km for trehalose was 0.78 mM, the pH optimum 5.5 and the temperature optimum 30 degrees C. 2. Trehalase represented approximately 50% of the total protein released by osmotic shock. The preparation was free of nonspecific carbohydrate hydrolases, which act on sucrose, galactose and maltose, permitting trehalose determination in biological samples, such as insect hemolymph and free cell extracts among others. 3. The enzyme was stable in 50 mM maleate buffer, pH 6.2, at -8 degrees C for at least 6 months and could be used to determine trehalose in the range of 6 to 30 nmol. 4. Immobilization of the enzyme was achieved by covalent linkage to spherisorb-5NH2 (spherical silica gel). Retention of total catalytic activity averaged 32%. 5. The reactor, stored for one month at -5 degrees C, retained 98% of its initial immobilized activity. 6. This immobilized form of the enzyme could be used routinely for specific determinations of trehalose.

Electrophoresis, Polyacrylamide Gel↗
PubMed2004

Transcriptional and post-translational regulation of neutral trehalase in Schizosaccharomyces pombe during thermal stress.

In the fission yeast Schizosaccharomyces pombe, a heat shock enhances transcription of the ntp1(+) gene, encoding the hydrolytic enzyme neutral trehalase. As compared to wild-type cells, cells devoid of the MAP kinase Sty1p showed a strong decrease in ntp1(+) expression induced by the temperature upshift, indicating that the stress-activated protein kinase (SAPK) pathway regulates the expression of this gene during heat shock. The transcription factor Atf1p, which is the main downstream target for Sty1p in the SAPK pathway, appears to be involved in such control, since ntp1(+) expression under heat shock proved to be significantly blocked in atf1(+)-disrupted cells. Serial deletion and point mutation analyses of the ntp1(+) promoter, as well as electrophoretic mobility shift assays, revealed the existence of a CRE-like element as the target for Atf1p-mediated expression under thermal stress. The relevance of two putative HSE elements located in the ntp1(+) promoter was also investigated for their potential role in regulating ntp1(+) transcription during heat shock. The results support a model in which heat-induced Atf1p binding to the CRE-like element favours the subsequent interaction of the heat shock factor (HSF) with HSE elements in the ntp1(+) promoter. Unlike what happens under osmostress or oxidative treatments, Sty1p has no role in the post-translational activation of neutral trehalase induced by heat shock in the fission yeast.

Activating Transcription Factor 1↗
PubMed1998

Reduction of glycogen in eggs of the silkworm, Bombyx mori, by use of a trehalase inhibitor, trehazolin, and diapause induction in glycogen-reduced eggs.

A new trehalase inhibitor, trehazolin, caused a potent inhibition of ovary trehalase in the silkworm, Bombyx mori. A single injection of trehazolin into pupae (40&mgr;g/animal) did not interfere with the accumulation of proteins and lipids, but markedly reduced glycogen content in eggs accompanied by a remarkable increase in hemolymph trehalose levels. The most potent effect of trehazolin was expressed in eggs that developed at the mid-stage of pupal-adult development. In these eggs glycogen content was reduced to a trace level, less than 3% of that of the control. The reduced glycogen content was almost restored to the control level by injection of glucose but not by trehalose. Trehazolin treatment influenced oviposition and larval hatching, whereas embryogenesis went on normally in glycogen-reduced eggs. Injection of synthetic diapause hormone into non-diapause type hosts induced an incidence of 45% diapause in the eggs and increased their glycogen content. Surprisingly, injection of trehazolin never affected diapause induction by the hormone, despite considerably reduced glycogen content in these eggs. Thus, our findings provide a new method for production of eggs containing various amounts of glycogen, and a novel system for analyzing diapause-associated metabolism besides the well-known glycogen-sorbitol metabolism.

Journal Article↗
PubMed1965

Intracellular trehalase of a hybrid yeast.

1. The trehalase found in an extract prepared from a yeast strain that cannot ferment trehalose was studied and characterized. The enzyme is highly specific for trehalose with K(m) 1.02x10(-2)m, and an optimum pH of 6.9. 2. It is inhibited by glucose and by trehalose 6-phosphate, and does not facilitate any significant transglucosylations. 3. pK values 7.7 and 5.8 were detected for the groups associated with binding of the non-ionized substrate to the enzyme. 4. The trehalase was found to be highly labile and was inhibited by thiol-binding reagents. 5. The possible role of this enzyme in the trehalose-dissimilation patterns in the yeast cell was evaluated.

Chromatography, Paper↗
PubMed1966

Trehalase from Dictyostelium discoideum: purification and properties.

The hydrolytic enzyme, trehalase, was isolated and purified approximately 90-fold from the cellular slime mold Dictyostelium discoideum. The purified trehalase has an optimal temperature of 45 degrees C and shows maximum activity at pH 5.5 in citrate buffer. Its Michaelis constant is 1.2x 10(-3)M.

Chemical Phenomena↗
PubMed1968

Histochemical localization of renal trehalase: demonstration of a tubular site.

Trehalase activity has been localized histochemically within the cortical tubules of the human, rabbit, and mouse kidneys. The specific localization of the enzyme supports the hypothesis that trehalase, in concert with a series of other enzymes which synthesize trehalose from glucose, functions in a mechanism for the reabsorption of glucose from the glomerular filtrate.

Absorption↗
PubMed1969

Do trehalose and trehalase function in renal glucose transport?

Maximum catalytic capacity for renal trehalase varied from 20 micromoles (of glucose produced per minute per gram of fresh tissue) for the armadillo down to zero for the rat, the cat, most turtles, fishes, and all birds and snakes investigated. Labeled trehalose could not be demonstrated in the kidney of the rabbit and the rat after injection with labeled glucose. These data do not support the hypothesis that trehalase and trehalose function in the transport of glucose through the kidney.

Adult↗
PubMed1976

Effect of various factors on the activity of trehalase from the larvae of Sesamia inferens Walker (Insect).

Trehalase from the salivary glands and the midgut of Sesamia inferens showed optimum activity at pH 5.8, and at temperatures of 50 and 60 degrees C respectively. The increase in the incubation period, enzyme concentration, and substrate concentration respectively increased the end-product, the hydrolysis, and the rate of hydrolysis of the substrate. Dialysis did not affect, tryptophan accelerated, and other amino acids and end-product inhibited the enzyme activity.

Amino Acids↗