scholarly journals Phosphorylation of arylsulphatase A occurs through multiple interactions with the UDP-N-acetylglucosamine-1-phosphotransferase proximal and distal to its retrieval site by the KDEL receptor

1999 ◽  
Vol 340 (3) ◽  
pp. 729-736 ◽  
Author(s):  
Frank DITTMER ◽  
Kurt VON FIGURA
Keyword(s):  
Lysosomal Enzymes ◽  
Inhibitory Effect ◽  
Phosphate Group ◽  
Site Specific ◽  
Arylsulphatase A ◽  
Kdel Receptor ◽  
Multiple Interactions ◽  
Phosphate Groups ◽  
Retention Signal ◽  
Ionophore Monensin

Phosphorylation of oligosaccharides of the lysosomal enzyme arylsulphatase A (ASA), which accumulate in the secretions of cells that mis-sort most of the newly synthesized lysosomal enzymes due to a deficiency of mannose 6-phosphate receptors, was found to be site specific. ASA residing within the secretory route of these cells contains about one third of the incorporated [2-3H]mannose in phosphorylated oligosaccharides. Oligosaccharides carrying two phosphate groups are almost 2-fold less frequent than those with one phosphate group and only a few of the phosphate groups are uncovered. Addition of a KDEL (Lys-Asp-Glu-Leu) retention signal prolongs the residence time of ASA within the secretory route 6-fold, but does not result in more efficient phosphorylation. In contrast, more than 90% of the [2-3H]mannose incorporated into secreted ASA (with or without a KDEL retention signal) is present in phosphorylated oligosaccharides. Those with two phosphate groups are almost twice as frequent as those with one phosphate group and most of the phosphate groups are uncovered. Thus, ASA receives N-acetylglucosamine 1-phosphate groups in a sequential manner at two or more sites located within the secretory route proximal and distal to the site where ASA is retrieved by the KDEL receptor, i.e. proximal to the trans-Golgi. At each of these sites up to two N-acetylglucosamine 1-phosphate groups can be added to a single oligosaccharide. Of several drugs known to inhibit transit of ASA through the secretory route only the ionophore monensin had a major inhibitory effect on phosphorylation, uncovering and sialylation.

ENZYMIC CHANGES IN THE CERVIX OF THE RAT AND HAMSTER DURING THE OESTROUS CYCLE AND THE EFFECT OF STEROIDS

1977 ◽  
Vol 72 (2) ◽  
pp. 153-161 ◽  
Author(s):  
ELIZABETH ZACHARIAH ◽  
N. R. MOUDGAL
Keyword(s):  
Alkaline Phosphatase ◽  
Specific Activity ◽  
Protein Biosynthesis ◽  
Hydrolytic Enzymes ◽  
Maximal Activity ◽  
Inhibitory Effect ◽  
Oestrous Cycle ◽  
Single Subcutaneous Injection ◽  
Arylsulphatase A ◽  
Phosphatase Alkaline

SUMMARY Changes in four hydrolytic enzymes, namely acid phosphatase, alkaline phosphatase, arylsulphatase A and B, of the cervix of the rat and hamster have been studied during the 4-day oestrous cycle. All four enzymes showed maximal activity on the day of oestrus and least activity on day 2 of dioestrus. All the enzymes showed significant reduction of activity after ovariectomy, arylsulphatase A and B showing the earliest changes in specific activity. A single subcutaneous injection of 0·02 μg oestradiol-17β/rat increased the specific activity of arylsulphatase A and B from the low ovariectomized level to that observed in control oestrous animals within 18 and 6 h respectively. A higher concentration of oestradiol-17β (2·0 μg) had an inhibitory effect. Progesterone was without effect on arylsulphatase B activity, but when given (2·0 mg) with 0·02 μg oestradiol-17β, it inhibited the response to oestrogen. Cycloheximide prevented the rise in arylsulphatase B activity occurring after oestrogen injection, suggesting a regulation of cervical arylsulphatase B at the level of protein biosynthesis. These results suggest that arylsulphatase B activity may be induced by oestrogen in the cervix of the rat.

The first 3′:5′-cyclic nucleotide–amino acid complex:L-His–cIMP

2012 ◽  
Vol 68 (8) ◽  
pp. o311-o316 ◽  
Author(s):  
Katarzyna Ślepokura
Keyword(s):  
Crystal Structure ◽  
Amino Acid ◽  
Cyclic Nucleotide ◽  
Phosphate Group ◽  
Specific Amino Acid ◽  
Π Stacking ◽  
Cyclic Phosphate ◽  
Nucleotide Recognition ◽  
Group Play ◽  
Phosphate Groups

In the crystal structure of the L-His–cIMP complex,i.e.L-histidinium inosine 3′:5′-cyclic phosphate [systematic name: 5-(2-amino-2-carboxyethyl)-1H-imidazol-3-ium 7-hydroxy-2-oxo-6-(6-oxo-6,9-dihydro-1H-purin-9-yl)-4a,6,7,7a-tetrahydro-4H-1,3,5,2λ5-furo[3,2-d][1,3,2λ5]dioxaphosphinin-2-olate], C6H10N3O2+·C10H10N4O7P−, the Hoogsteen edge of the hypoxanthine (Hyp) base of cIMP and the Hyp face are engaged in specific amino acid–nucleotide (His...cIMP) recognition,i.e.by abutting edge-to-edge and by π–π stacking, respectively. The Watson–Crick edge of Hyp and the cIMP phosphate group play a role in nonspecific His...cIMP contacts. The interactions between the cIMP anions (anti/C3′–endo/trans–gauche/chair conformers) are realized mainly between riboses and phosphate groups. The results for this L-His–cIMP complex, compared with those for the previously reported solvated L-His–IMP crystal structure, indicate a different nature of amino acid–nucleotide recognition and interactions upon the 3′:5′-cyclization of the nucleotide phosphate group.

The Position of Phosphate Groups in the Phosphonomannan of Hansenula capsulata, as Determined by Carbon-13 Magnetic Resonance Spectroscopy

1973 ◽  
Vol 51 (13) ◽  
pp. 2105-2109 ◽  
Author(s):  
Philip A. J. Gorin
Keyword(s):  
Magnetic Resonance ◽  
Magnetic Resonance Spectroscopy ◽  
Spectral Data ◽  
Resonance Spectrum ◽  
Phosphate Group ◽  
Resonance Spectroscopy ◽  
Previous Assignment ◽  
Phosphate Groups

The carbon-13 magnetic resonance spectrum of a phosphate of 2-O-β-D-mannopyranosyl-α,β-D-mannose was compared with that of the unphosphorylated disaccharide. The positions and number of the signals of C-5's which are coupled to phosphorus-31, together with other spectral data show that the phosphate group is on C-6 of the reducing end-unit (2, Fig. 1). This differs from a previous assignment (1), thus necessitating a revision (4) to the structure 3 proposed for the parent Hansenula capsulata phosphonomannan.

scholarly journals Antiribophorin antibodies inhibit the targeting to the ER membrane of ribosomes containing nascent secretory polypeptides.

1990 ◽  
Vol 111 (4) ◽  
pp. 1335-1342 ◽  
Author(s):  
Y H Yu ◽  
D D Sabatini ◽  
G Kreibich
Keyword(s):  
Protein Synthesis ◽  
Polyclonal Antibodies ◽  
Liver Microsomes ◽  
Inhibitory Effect ◽  
Secretory Protein ◽  
Rat Liver Microsomes ◽  
Membrane Glycoproteins ◽  
Site Specific ◽  
Dog Pancreas ◽  
Er Membrane

Polyclonal antibodies directed against ribophorins I and II, two membrane glycoproteins characteristic of the rough endoplasmic reticulum, inhibit the cotranslational translocation of a secretory protein growth hormone into the lumen of dog pancreas or rat liver microsomes. As expected, site-specific antibodies to epitopes located within the cytoplasmic domain of ribophorin I, but not antibodies to epitopes in the luminal domain of this protein, were effective in inhibiting translocation. Since monovalent Fab fragments were as inhibitory as intact IgG molecules, ribophorins must be closely associated with the translocation site and, therefore, are likely to function at some stage in the translocation process. In all cases, the antibodies that inhibited translocation also caused a significant reduction in total protein synthesis and treatments that neutralized their capacity to inhibit translocation also prevented their inhibitory effect on protein synthesis. This would be expected if the antibodies blocked the membrane-mediated relief of the SRP-induced arrest of polypeptide elongation. The antibodies were effective only when added before translocation was allowed to begin. In this case, they prevented the targeting of active ribosomes containing mRNA and nascent chains to the ER membrane. Thus, ribophorins must either directly participate in targeting or be so close to the targeting site that the antibodies sterically blocked this early phase of the translocation process.

scholarly journals Purification and properties of arylsulphatase A from chicken brain

1972 ◽  
Vol 126 (4) ◽  
pp. 1025-1033 ◽  
Author(s):  
A. A. Farooqui ◽  
B. K. Bachhawat
Keyword(s):  
Animal Species ◽  
Polyacrylamide Gel Electrophoresis ◽  
Gel Filtration ◽  
Inhibitory Effect ◽  
Inorganic Pyrophosphatase ◽  
Kinetic Properties ◽  
Time Activity ◽  
Sephadex Column ◽  
Chicken Brain ◽  
Arylsulphatase A

1. Chicken brain arylsulphatase A was purified 2000-fold, with overall recovery 14%, by using ammonium sulphate fractionation, ethanol precipitation, Sephadex G-200 gel filtration and DEAE-Sephadex column chromatography. 2. The purified preparation was free from β-glucuronidase, β-galactosidase, acid phosphatase, inorganic pyrophosphatase and adenosine 3′-phosphate 5′-sulphatophosphate sulphohydrolase activities. 3. Polyacrylamide-gel electrophoresis indicated that the purified preparation was not homogeneous. 4. Chicken brain arylsulphatase was markedly inhibited by carbonyl reagents in the presence of traces of Cu2+ in the system. Other metal ions such as Fe2+ and Zn2+, were inactive. 5. Ascorbic acid alone had no effect on enzyme activity but enhances the inhibition by Cu2+. 6. Chicken brain arylsulphatase A resembled arylsulphatase A of other animal species in its kinetic properties such as Km value, anomalous time–activity relationship and the inhibitory effect of phosphate, sulphite and sulphate ions. However, its electrophoretic mobility, behaviour under zinc acetate fractionation and stimulation by Ag+ were similar to arylsulphatase B of other animal species. Thus, this enzyme did not correspond to either arylsulphatase A or arylsulphatase B but properties of both. 7. The purified enzyme preparation can degrade cerebroside 3-sulphate.

Adsorption between TC-stabilized AuNPs and the phosphate group: application of the PTP1B activity assay

The Analyst ◽  
2015 ◽  
Vol 140 (23) ◽  
pp. 8017-8022 ◽  
Author(s):  
Jun Lv ◽  
Xiaonan Wang ◽  
Yuanyuan Zhang ◽  
Defeng Li ◽  
Juan Zhang ◽  
...  
Keyword(s):  
Gold Nanoparticles ◽  
Magnetic Nanoparticles ◽  
Colorimetric Method ◽  
Phosphate Group ◽  
Activity Assay ◽  
Phosphate Groups

Based on the adsorption between tetracycline (TC) and phosphate groups, a general colorimetric method is explored in this work by using TC-stabilized gold nanoparticles (TC/AuNPs) and 4-aminophenyl phosphate-functionalized Fe3O4 magnetic nanoparticles (APP/MNPs).

scholarly journals Aqueous Contact Ion Pairs of Phosphate Groups with Na+, Ca2+ and Mg2+ – Structural Discrimination by Femtosecond Infrared Spectroscopy and Molecular Dynamics Simulations

2020 ◽  
Vol 234 (7-9) ◽  
pp. 1453-1474 ◽  
Author(s):  
Benjamin P. Fingerhut ◽  
Jakob Schauss ◽  
Achintya Kundu ◽  
Thomas Elsaesser
Keyword(s):  
Ion Pairs ◽  
Model System ◽  
Ion Pair ◽  
Pair Formation ◽  
Phosphate Group ◽  
Phosphate Ion ◽  
2D Ir ◽  
Dna And Rna ◽  
Contact Ion Pairs ◽  
Phosphate Groups

AbstractThe extent of contact and solvent shared ion pairs of phosphate groups with Na+, Ca2+ and Mg2+ ions in aqueous environment and their relevance for the stability of polyanionic DNA and RNA structures is highly debated. Employing the asymmetric phosphate stretching vibration of dimethyl phosphate (DMP), a model system of the sugar-phosphate backbone of DNA and RNA, we present linear infrared, femtosecond infrared pump-probe and absorptive 2D-IR spectra that report on contact ion pair formation via the presence of blue shifted spectral signatures. Compared to the linear infrared spectra, the nonlinear spectra reveal contact ion pairs with increased sensitivity because the spectra accentuate differences in peak frequency, transition dipole moment strength, and excited state lifetime. The experimental results are corroborated by long time scale MD simulations, benchmarked by density functional simulations on phosphate-ion-water clusters. The microscopic interpretation reveals subtle structural differences of ion pairs formed by the phosphate group and the ions Na+, Ca2+ and Mg2+. Intricate properties of the solvation shell around the phosphate group and the ion are essential to explain the experimental observations. The present work addresses a challenging to probe topic with the help of a model system and establishes new experimental data of contact ion pair formation, thereby underlining the potential of nonlinear 2D-IR spectroscopy as an analytical probe of phosphate-ion interactions in complex biological systems.

Nanostructured and Electroactive Hybrid Films Containing Microcrystalline Cellulose Modified with the Phosphate Group: Synthesis and Characterization

2016 ◽  
Vol 869 ◽  
pp. 840-845
Author(s):  
Paulo Ronaldo Sousa Teixeira ◽  
Ana Siqueira do Nascimento Marreiro ◽  
José Regilmar Teixeira da Silva ◽  
Emanuel Airton de Oliveira Farias ◽  
Natália de Araujo Dionisio ◽  
...  
Keyword(s):  
Microcrystalline Cellulose ◽  
Self Assembly ◽  
Phosphate Group ◽  
Synthesis And Characterization ◽  
Layer By Layer ◽  
Preparation Process ◽  
Hybrid Films ◽  
Assembly Technique ◽  
Phosphate Groups ◽  
Modified Cellulose

Nanostructured and electroactive hybrid films containing Microcrystalline Cellulose (MC) modified with the phosphate group (MCPO4) and polyaniline (PANI) were prepared using the Layer-by-Layer (LbL) self-assembly technique. In the preparation process of the films cellulose was dispersed in the solution of PANI and the film with PVS/PANI(MCPO4) structure was immobilized on ITO substrate. In order to investigate the influence of the phosphate group on the electrochemical behavior of the film, films were also prepared replacing the modified cellulose (MCPO4) by unmodified cellulose (MC), forming the PVS/PANI(MC) films. Subsequently, all films were characterized by cyclic voltammetry (CV), and the results showed the redox processes characteristic of PANI, but the presence of CMPO4 promotes an increase in the values of current density observed for the PVS/PANI(MCPO4) film when compared to the PVS/PANI(MC) film. This is probably due to a self-doping process of the polymer in the presence of phosphate groups.

INHIBITORY EFFECT OF DIBUTYRYL CYCLIC AMP ON THE RELEASE OF CALCIUM, INORGANIC PHOSPHATE AND LYSOSOMAL ENZYMES FROM CALVARIAL BONES CULTURED FOR 24 HOURS

1979 ◽  
Vol 91 (4) ◽  
pp. 730-742 ◽  
Author(s):  
U. Lerner ◽  
G. T. Gustafson
Keyword(s):  
Bone Resorption ◽  
Culture System ◽  
Inorganic Phosphate ◽  
Lysosomal Enzymes ◽  
Inhibitory Effect ◽  
Bone Culture ◽  
Dibutyryl Cyclic Amp ◽  
The Media ◽  
Old Mice ◽  
Release Processes

ABSTRACT The effect of N6,O2′-dibutyryl adenosine 3′,5′-cyclic-monophosphate (dbcAMP) on the mobilization of calcium (Ca2 +), inorganic phosphate (Pi) and lysosomal enzymes was studied in a bone culture system for 24 h using half calvaria from 6–7 day-old mice. DbcAMP inhibited spontaneous as well as parathyroid hormone-stimulated mineral mobilization. DbcAMP in a concentration of 5 × 10−4m also reduced the activities of β-glucuronidase, β-galactosidase and acid phosphatase found in the media while the activities of lactate dehydrogenase, aspartate aminotransferase and alanine aminotransferase were not affected. It is concluded that cAMP is not a stimulator but an inhibitor of bone resorption within the culture period studied (24 h) and that the cyclic nucleotide might interfere with release processes involved in bone resorption.

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