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NLM database Documents
Record 1 from database: MEDLINE
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- Title
- Role of cholesterol 10-methyl group and effect of
"extra" 14-methyl group on silkworm growth and
development.
- Author
- Mamiya M; Takahashi K; Eguchi S; Morisaki M
- Address
-
- Source
- Chem Pharm Bull (Tokyo), 1989 Jul, 37:7, 1930-1
- Abstract
- In order to establish the functional importance of the
10-methyl group of cholesterol and the planarity of the
steroid ring, silkworms (Bombyx mori) were reared on an
artificial diet containing 19-norcholesterol (1), 14 alpha-methylcholesterol
(3) or 19,19-difluorocholesterol (2). The former two sterols
(1 and 3) only partially satisfied the silkworm sterol
requirement; growth and development were seriously retarded.
The fluorinated sterol (2) was much more deleterious and was
totally inadequate in meeting the sterol requirement.
- Language of Publication
- English
- Unique Identifier
- 90030589
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- MeSH Heading (Major)
- Cholesterol|AA/*PD; Silkworms|*GD
- MeSH Heading
- Animal; Structure-Activity Relationship
- Publication Type
- JOURNAL ARTICLE
- ISSN
- 0009-2363
- Country of Publication
- JAPAN
Record 2 from database: MEDLINE
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- Title
- The allyl group for protection in carbohydrate chemistry.
17. Synthesis of propyl
O-(3,6-di-O-methyl-beta-D-glucopyranosyl)-(1----4)-O-(2,3-
di-O-methyl-alpha-L-rhamnopyranosyl)-(1----2)-3-O-methyl-alpha-
L-rhamnopyranoside: the oligosaccharide portion of the major
serologically active glycolipid from Mycobacterium leprae.
- Author
- Gigg J; Gigg R; Payne S; Conant R
- Address
-
- Source
- Chem Phys Lipids, 1985 Sep, 38:3, 299-307
- Abstract
- Allyl 4-O-benzyl-alpha-L-rhamnopyranoside was converted
into allyl 4-O-benzyl-3-O-methyl-alpha-L-rhamnopyranoside
and this was condensed with
2,3,4-tri-O-acetyl-alpha-L-rhamnopyranosyl chloride to give
a disaccharide derivative which was converted into allyl
4-O-benzyl-2-O-(2,3-O-isopropylidene-alpha-L-rhamnopyranosyl)-3-O-methyl
-alpha- L-rhamnopyranoside. This disaccharide derivative was
condensed with
2,4-di-O-acetyl-3,6-di-O-methyl-alpha-D-glucopyranosyl
chloride to give a trisaccharide derivative which was
converted into the title compound. This compound represents
the oligosaccharide portion of the major serologically
active glycolipid from Mycobacterium leprae which is
required to prepare a synthetic diagnostic agent for leprosy
infection at an early stage and to investigate the
specificities of monoclonal antibodies directed towards the
glycolipid.
- Language of Publication
- English
- Unique Identifier
- 86106478
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- MeSH Heading (Major)
- Glycolipids|*CS; Mycobacterium leprae|*IM;
Oligosaccharides|*CS; Trisaccharides|*CS
- MeSH Heading
- Indicators and Reagents; Optical Rotation; Support, Non-U.S.
Gov't
- Publication Type
- JOURNAL ARTICLE
- ISSN
- 0009-3084
- Country of Publication
- NETHERLANDS
Record 3 from database: MEDLINE
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- Title
- Methyl-glyoxal bis guanyl hydrazone (methyl-GAG, MGBG) in
lymphoma and Hodgkin's disease. A Phase II trial of the
Southwest Oncology Group.
- Author
- Knight WA 3d; Fabian C; Costanzi JJ; Jones SE; Coltman CA
Jr
- Address
-
- Source
- Invest New Drugs, 1983, 1:3, 235-7
- Abstract
- The Southwest Oncology Group has evaluated methyl-GAG on a
weekly schedule among patients with lymphoma and Hodgkin's
disease. Among 56 fully and partially evaluable patients
responses were seen in 3 of 10 patients with Hodgkin's
disease and 11 of 46 patients with lymphoma. Toxicity was
acceptable. Methyl-GAG has significant antitumor activity
among this group of heavily pretreated patients. Additional
trials of methyl-GAG in combination with other agents are
underway.
- Language of Publication
- English
- Unique Identifier
- 84288336
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- MeSH Heading (Major)
- Guanidines|*TU; Hodgkin Disease|*DT; Lymphoma|*DT;
Mitoguazone|AE/*TU
- MeSH Heading
- Adolescence; Adult; Aged; Drug Evaluation; Female; Human;
Male; Middle Age; Support, U.S. Gov't, P.H.S.
- Publication Type
- JOURNAL ARTICLE
- ISSN
- 0167-6997
- Country of Publication
- UNITED STATES
Record 4 from database: MEDLINE
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- Title
- Evidence for methyl group transfer between the
methyl-accepting chemotaxis proteins in Bacillus subtilis.
- Author
- Bedale WA; Nettleton DO; Sopata CS; Thoelke MS; Ordal GW
- Address
- Department of Biochemistry, College of Medicine,
University of Illinois, Urbana 61801.
- Source
- J Bacteriol, 1988 Jan, 170:1, 223-7
- Abstract
- We present evidence for methyl (as methyl or methoxy)
transfer from the methyl-accepting chemotaxis proteins H1
and possibly H3 of Bacillus subtilis to the methyl-accepting
chemotaxis protein H2. This methyl transfer, which has been
observed in vitro (D. J. Goldman and G. W. Ordal,
Biochemistry 23:2600-2606, 1984), was strongly stimulated by
the chemoattractant aspartate and thus may play an important
role in the sensory processing system of this organism.
Although radiolabeling of H1 and H3 began at once after the
addition of [3H]methionine, radiolabeling of H2 showed a
lag. Furthermore, the addition of excess nonradioactive
methionine caused immediate exponential delabeling of H1 and
H3 while labeling of H2 continued to increase. Methylation
of H2 required the chemotactic methyltransferase, probably
to first methylate H1 and H3. Aspartate caused increased
labeling of H2 and strongly decreased labeling of H1 and H3
after the addition of nonradioactive methionine. Without the
addition of nonradioactive methionine, aspartate caused
demethylation of H1 and to a lesser extent H3, with an
approximately equal increase of methylation of H2.
- Language of Publication
- English
- Unique Identifier
- 88086873
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- MeSH Heading (Major)
- Bacillus subtilis|*ME; Chemotactic Factors|*ME; Membrane
Proteins|*ME
- MeSH Heading
- Electrophoresis, Polyacrylamide Gel; Methylation; Support,
U.S. Gov't, Non-P.H.S.; Support, U.S. Gov't, P.H.S.
- Publication Type
- JOURNAL ARTICLE
- ISSN
- 0021-9193
- Country of Publication
- UNITED STATES
Record 5 from database: MEDLINE
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- Title
- The methyl folate trap. A physiological response in man to
prevent methyl group deficiency in kwashiorkor (methionine
deficiency) and an explanation for folic-acid induced
exacerbation of subacute combined degeneration in pernicious
anaemia.
- Author
- Scott JM; Weir DG
- Address
-
- Source
- Lancet, 1981 Aug, 2:8242, 337-40
- Abstract
- It is suggested that in man the methyl folate trap is a
normal physiological response to impending methyl group
deficiency resulting from a very low supply of methionine.
This decreases cellular S-adenosyl-methionine (SAM), which
puts at risk important methylation reactions, including
those required to maintain myelin. In order to protect these
methylation reactions, the cell has evolved two mechanisms
to maintain supplies of methionine and SAM as a first
priority. (a) Decreased SAM causes the folate co-factors to
be directed through the cycle involving
5-methyl-tetrahydrofolate (5-methyl-THF) and methionine
synthetase and away from the cycles that produce purines and
pyrimidines for DNA synthesis. This enhances the
remethylation of homocysteine to methionine and SAM. In
addition, by restricting DNA biosynthesis and with it cell,
division, competition for methionine for protein synthesis
is reduced. Thus, whatever methionine is available is
conserved for the vital methylation reactions in the nerves,
brain, and elsewhere. (b) 5-methyl-THF, the form in which
almost all folate is transported in human plasma, must react
with intracellular homocysteine before it can be retained by
the cell as a polyglutamate. Since homocysteine is derived
entirely from methionine, methionine deficiency will cause
intracellular folate deficiency, and the rate of mitosis of
rapidly dividing cells will be reduced. although these two
processes have evolved as a response to methionine
deficiency, they also occur in B12 deficiency, which the
cell mistakenly interprets as lack of methionine. the
resulting response is inappropriate and gives rise to a
potentially lethal anaemia. In these circumstances the
methylation reactions are also partly protected by the
reduced rate of cell division. This explains why
administration of folic acid, which induces cell division
and use of methionine in protein synthesis, impairs
methylation of myelin and precipitates or exacerbates
subacute combined degeneration (SCD). During folate
deficiency methionine biosynthesis is also diminished. As in
methionine deficiency, the body responds to decreasing
availability of SAM by diverting folate away from DNA
biosynthesis towards the remethylation of homocysteine to
methionine and SAM. The selective use pf available folate to
conserve methionine, together with the ability of nerve
tissue to concentrate folate form the plasma, explains the
absence of SCD in folate deficiency.
- Language of Publication
- English
- Unique Identifier
- 81269413
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- MeSH Heading (Major)
- Anemia, Pernicious|*ME; Folic Acid|*PH; Kwashiorkor|*PC;
Methionine|*DF/PH; Methotrexate|*AA/ME; Models, Biological|*
- MeSH Heading
- Acute Disease; Bone Marrow|ME; Cell Division; Folic Acid
Deficiency|CO; Human; Vitamin B 12 Deficiency|CO
- Publication Type
- JOURNAL ARTICLE
- ISSN
- 0140-6736
- Country of Publication
- ENGLAND
Record 6 from database: MEDLINE
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- Title
- Influence of the presence of a methyl group on the
myocardial metabolism of 15-(paraiodophenyl)-3 methyl
pentadecanoic acid (IMPPA).
- Author
- Humbert T; Keriel C; Batlle DM; Leverve X; Luu Duc C;
Cuchet P; Comet M
- Address
- Laboratoire de Chimie Pharmacie, URA CNRS 1287, Grenoble,
France.
- Source
- Int J Rad Appl Instrum [B], 1990, 17:8, 745-9
- Abstract
- The objective of the present study was to determine the
mechanism of accumulation of myocardial activity following
i.v. injection of 15-(paraiodophenyl)-3 methyl pentadecanoic
acid (IMPPA). IMPPA and 15 phenyl-3 methyl pentadecanoic
acid (MPPA) were labeled with 14C at position 1 and used to
perfuse isolated rat hearts in a closed system. After 5 min
of perfusion, IMPPA reached 2/3 of its value at 45 min.
14CO2 production was low. Most of the myocardial activity
was in the form of free IMPPA. Analysis of IMPPA activation
by CoA SH revealed that it was very strongly inhibited. The
retention of myocardial activity is thus due to
intracellular accumulation of free IMPPA following
inhibition of activation. Comparison of results obtained
with IMPPA and MPPA showed that the presence of iodine in
the molecule accentuates the inhibition of activation.
- Language of Publication
- English
- Unique Identifier
- 91177698
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- MeSH Heading (Major)
- Iodobenzenes|*PK; Myocardium|*ME
- MeSH Heading
- Animal; Carbon Radioisotopes; Coenzyme A Ligases; Fatty
Acids|PK; Female; In Vitro; Rats; Rats, Inbred Strains
- Publication Type
- JOURNAL ARTICLE
- ISSN
- 0883-2897
- Country of Publication
- UNITED STATES
Record 7 from database: MEDLINE
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- Title
- Reductive activation of the corrinoid-containing enzyme
involved in methyl group transfer between methyl-tetrahydromethanopterin
and coenzyme M in Methanosarcina barkeri.
- Author
- van de Wijngaard WM; Lugtigheid RL; van der Drift C
- Address
- Department of Microbiology, Faculty of Science, University
of Nijmegen, The Netherlands.
- Source
- Antonie Van Leeuwenhoek, 1991 Jul, 60:1, 1-6
- Abstract
- The conversion of methyl-tetrahydromethanopterin to
methylcoenzyme M in Methanosarcina barkeri is catalyzed by
two enzymes: an enzyme with a bound corrinoid, which becomes
methylated during the reaction and an enzyme which transfers
the methyl group from this corrinoid to coenzyme M. As in
the similar methyltransfer reaction in Methanobacterium
thermoautotrophicum the corrinoid enzyme in M barkeri needs
to be activated by H2 and ATP. ATP can be replaced by
Ti(III)citrate or CO.
- Language of Publication
- English
- Unique Identifier
- 92181106
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- MeSH Heading (Major)
- Mesna|*AA/ME; Methanosarcina barkeri|*EN/ME;
Methyltransferases|*CH; Pterins|*ME
- MeSH Heading
- Adenosine Triphosphate|ME; Carbon Monoxide|ME; Citrates|ME;
Enzyme Activation; Formaldehyde|ME; Hydrogen|ME; Methylation;
Oxidation-Reduction; Support, Non-U.S. Gov't
- Publication Type
- JOURNAL ARTICLE
- ISSN
- 0003-6072
- Country of Publication
- NETHERLANDS
Record 8 from database: MEDLINE
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- Title
- Methyl-glyoxal bis guanyl hydrazone (methyl-GAG, MGBG) in
advanced breast cancer. A Phase II trial of the Southwest
Oncology Group.
- Author
- Knight WA 3d; OBryan RM; Samal B; Costanzi JJ
- Address
-
- Source
- Invest New Drugs, 1984, 2:1, 71-3
- Abstract
- The Southwest Oncology Group has evaluated methyl-GAG on a
weekly schedule among patients with metastatic breast
cancer. Among 72 fully and partial evaluable patients, one
complete and four partial responses were seen. Toxicity was
similar to other trials with this compound except for
thrombocytopenia which was more frequent and severe and
probably related to tumor infiltrating marrow. In addition,
one patient experienced recall dermatitis following
methyl-GAG. This toxicity has not been previously reported
with this compound. Methyl-GAG has minimal activity at this
dose and schedule among heavily pretreated patients with
breast cancer.
- Language of Publication
- English
- Unique Identifier
- 84288364
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- MeSH Heading (Major)
- Breast Neoplasms|*DT; Guanidines|*TU; Mitoguazone|AE/*TU
- MeSH Heading
- Adult; Aged; Drug Evaluation; Female; Human; Middle Age;
Neoplasm Metastasis; Support, U.S. Gov't, P.H.S.;
Thrombocytopenia|CI
- Publication Type
- JOURNAL ARTICLE
- ISSN
- 0167-6997
- Country of Publication
- UNITED STATES
Record 9 from database: MEDLINE
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- Title
- Influence of attractants and repellents on methyl group
turnover on methyl-accepting chemotaxis proteins of Bacillus
subtilis and role of CheW.
- Author
- Hanlon DW; Carpenter PB; Ordal GW
- Address
- Department of Biochemistry, College of Medicine,
University of Illinois, Urbana 61801.
- Source
- J Bacteriol, 1992 Jul, 174:13, 4218-22
- Abstract
- The ability of attractants and repellents to affect the
turnover of methyl groups on the methyl-accepting chemotaxis
proteins (MCPs) was examined for Bacillus subtilis.
Attractants were found to cause an increase in the turnover
of methyl groups esterified to the MCPs, while repellents
caused a decrease. These reactions do not require CheW.
However, a cheW null mutant exhibits enhanced turnover in
unstimulated cells. Assuming that the turnover of methyl
groups on the MCPs reflects a change in the activity of CheA,
these results suggest that the activation of CheA via
chemoeffector binding at the receptor does not require CheW.
- Language of Publication
- English
- Unique Identifier
- 92325003
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- MeSH Heading (Major)
- Bacillus subtilis|DE/*PH; Bacterial Proteins|BI/*ME;
Chemotactic Factors|*PH
- MeSH Heading
- Butyrates|PD; Chemotaxis; Kinetics; Methionine|ME;
Methylation; Support, U.S. Gov't, P.H.S.; Tritium
- Publication Type
- JOURNAL ARTICLE
- ISSN
- 0021-9193
- Country of Publication
- UNITED STATES
Record 10 from database: MEDLINE
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- Title
- Formation of N-(glutathion-S-methylene)-4-aminoazobenzene
following metabolic oxidation of the N-methyl group of the
carcinogen, N-methyl-4-aminoazobenzene.
- Author
- Ketterer B; Srai SK; Waynforth B; Tullis DL; Evans FE;
Kadlubar FF
- Address
-
- Source
- Chem Biol Interact, 1982 Feb, 38:3, 287-302
- Abstract
- A major biliary metabolite of the hepatocarcinogen,
N,N-dimethyl-4-aminoazobenzene (DAB), in the rat was
identified as N-(glutathion-S-methylene)-4-aminoazobenzene
(GS-CH2-AB). This conjugate was prepared synthetically by a
Mannich condensation of 4-aminoazobenzene (AB), formaldehyde
(CH2O) and glutathione (GSH) and has been characterized by
chemical analysis and by ultraviolet, visible and 13C-NMR
spectroscopy. The same conjugate was also formed in vitro by
incubating N-methyl-4-aminoazobenzene (MAB), NADPH, NADH and
GSH with rat hepatic microsomes. Evidence is presented that
GSH reacted with an intermediate resulting from a cytochrome
P-450-dependent oxidation of the N-methyl substituent. This
reactive intermediate is presumed to be either an N-methylol
or a methimine derivative of AB. The significance of this
detoxification mechanism is discussed. The presence of an
additional major aminoazo-dye GSH conjugate is also noted.
- Language of Publication
- English
- Unique Identifier
- 82137284
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- MeSH Heading (Major)
- p-Aminoazobenzene|AA/*ME; Azo Compounds|*ME;
Carcinogens|*ME
- MeSH Heading
- p-Dimethylaminoazobenzene|ME; Animal; Bile|ME; Comparative
Study; Glutathione|ME; In Vitro; Male; Metabolic
Detoxication, Drug; Microsomes, Liver|ME; Rats; Rats, Inbred
Strains; Support, Non-U.S. Gov't; Support, U.S. Gov't, Non-P.H.S.
- Publication Type
- JOURNAL ARTICLE
- ISSN
- 0009-2797
- Country of Publication
- NETHERLANDS
Record 11 from database: MEDLINE
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- Title
- When is a trifluoromethyl group more lipophilic than a
methyl group? Partition coefficients and selected chemical
shifts of aliphatic alcohols and trifluoroalcohols.
- Author
- Muller N
- Address
-
- Source
- J Pharm Sci, 1986 Oct, 75:10, 987-91
- Abstract
- Octanol-water partition coefficients were determined for
12 trifluoromethylated aliphatic alcohols and their
unfluorinated counterparts. The latter values were derived
from measurements using the benzyl alcohol-water solvent
system after developing an appropriate correlation equation.
Incidentally, an empirical equation was found which allows
the partition coefficient of an unsubstituted alcohol to be
estimated given the molecular formula and boiling point.
Trifluorination strongly enhances lipophilicity only when
the trifluoromethyl group is in the alpha-position. The
enhancement is barely measurable for the beta- and gamma-(trifluoromethyl)
alcohols, while the delta- and epsilon-(trifluoromethyl)
compounds are considerably more hydrophilic than their
parent compounds. Chemical shift comparisons suggest that
the changes in relative lipophilicity are controlled
primarily by the inductive effect of the trifluoromethyl
group on the acidity-basicity of the hydroxyl group. New
synthetic procedures for obtaining some of the alcohols are
presented.
- Language of Publication
- English
- Unique Identifier
- 87086307
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- MeSH Heading (Major)
- Alcohols|*AN; Hydrocarbons, Fluorinated|*AN
- MeSH Heading
- Chemistry, Physical; Lipids; Nuclear Magnetic Resonance;
Solubility
- Publication Type
- JOURNAL ARTICLE
- ISSN
- 0022-3549
- Country of Publication
- UNITED STATES
Record 12 from database: MEDLINE
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- Title
- Molecular structure of (m5 dC-dG)3: the role of the methyl
group on 5-methyl cytosine in stabilizing Z-DNA.
- Author
- Fujii S; Wang AH; van der Marel G; van Boom JH; Rich A
- Address
-
- Source
- Nucleic Acids Res, 1982 Dec, 10:23, 7879-92
- Abstract
- The hexamer (m5 dC-dG)3 has been synthesized and its
three-dimensional structure determined by a single crystal
X-ray diffraction analysis. The structure has been refined
to a final R value of 15.6% at 1.3 A resolution. The
molecule forms a left-handed Z-DNA helix which is similar to
the unmethylated Z-DNA structure. The presence of the methyl
group has resulted in slight changes in the twist angle
between successive base pairs and modification of some of
the interatomic contacts. Methylation of cytosine in the C5
position is associated with a relative destabilization of
the B-DNA structure and a stabilization through hydrophobic
bonding of the Z-DNA structure.
- Language of Publication
- English
- Unique Identifier
- 83116999
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- MeSH Heading (Major)
- Cytosine|*AA/AN; DNA|*; Oligodeoxyribonucleotides|*/CS;
Oligonucleotides|*/CS
- MeSH Heading
- Base Sequence; Models, Molecular; Nucleic Acid
Conformation; Support, Non-U.S. Gov't; Support, U.S. Gov't,
Non-P.H.S.; Support, U.S. Gov't, P.H.S.; X-Ray Diffraction
- Publication Type
- JOURNAL ARTICLE
- ISSN
- 0301-5610
- Country of Publication
- ENGLAND
Record 13 from database: MEDLINE
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- Title
- Methyl group turnover on methyl-accepting chemotaxis
proteins during chemotaxis by Bacillus subtilis.
- Author
- Thoelke MS; Casper JM; Ordal GW
- Address
- Department of Biochemistry, University of Illinois, Urbana
61801.
- Source
- J Biol Chem, 1990 Feb, 265:4, 1928-32
- Abstract
- The addition of attractant to Bacillus subtilis briefly
exposed to radioactive methionine causes an increase of
labeling of the methyl-accepting chemotaxis proteins. The
addition of attractant to cells radiolabeled for longer
times shows no change in the extent of methylation.
Therefore, the increase in labeling for the briefly labeled
cells is due to an increased turnover of methyl groups
caused by attractant. All amino acids gave enhanced
turnover. This turnover lasted for a prolonged time,
probably spanning the period of smooth swimming caused by
the attractant addition. Repellent did not affect the
turnover when added alone or simultaneously with attractant.
Thus, for amino acid attractants, the turnover is probably
the excitatory signal, which is seen to extend long into or
throughout the adaptation period, not just at the start of
it.
- Language of Publication
- English
- Unique Identifier
- 90130434
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- MeSH Heading (Major)
- Bacillus subtilis|DE/*ME; Chemotactic Factors|*ME;
Chemotaxis|*; Membrane Proteins|*ME
- MeSH Heading
- Amino Acids|PD; Kinetics; Methionine|ME; Methylation;
Radioisotope Dilution Technique; Support, U.S. Gov't, Non-P.H.S.;
Support, U.S. Gov't, P.H.S.; Tritium
- Publication Type
- JOURNAL ARTICLE
- ISSN
- 0021-9258
- Country of Publication
- UNITED STATES
Record 14 from database: MEDLINE
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- Title
- Synthesis of benzyl
O-(2-O-methyl-beta-D-galactopyranosyl)-(1----3)-2-
acetamido-2-deoxy-beta-D-glucopyranoside [benzyl
2'-O-methyllacto-N-bioside I], and its higher saccharide
containing an O-(2-O-methyl-beta-D- galactopyranosyl)-(1----3)-2-acetamido-2-deoxy-beta-D-glucopyranosyl
group as a potential substrate for
(1---4)-alpha-L-fucosyltransferase.
- Author
- Sarkar AK; Jain RK; Matta KL
- Address
- Department of Gynecologic Oncology, Roswell Park Memorial
Institute, Buffalo, New York 14263.
- Source
- Carbohydr Res, 1990 Aug, 203:1, 33-46
- Abstract
- Treatment of benzyl O-beta-D-galactopyranosyl-(1----3)-2-acetamido-2-
deoxy-4,6-O-isopropylidene-beta-D-glucopyranoside with
tert-butylchlorodiphenylsilane afforded the
6'-O-tert-butyldiphenylsilyl ether, which was converted into
the 3',4'-O-isopropylidene derivative. Methylation and
subsequent removal of protecting groups afforded benzyl
O-(2-O-methyl-beta-D-galactopyranosyl)-
(1----3)-2-acetamido-2-deoxy-beta-D-glucopyranoside (7). The
trisaccharide methyl
O-(2-O-methyl-beta-D-galactopyranosyl)-(1----3)-O-(2-
acetamido-2-deoxy-beta-D-glucopyranosyl)-(1----3)-beta-D-galactopyranosi
de (17) and the tetrasaccharide
O-(2-O-methyl-beta-D-galactopyranosyl)-(1----3)-O-(2-acetamido-2-deoxy-b
eta-D- glucopyranosyl)-(1----3)-O-beta-D-galactopyranosyl-(1----4)-D-glucopyran
ose (32), both containing the 2'-O-methyllacto-N-biose I
unit at the nonreducing end, were synthesized, and the
structures of 7, 17, and 32 were confirmed by 13C-n.m.r.
spectroscopy.
- Language of Publication
- English
- Unique Identifier
- 91029258
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- MeSH Heading (Major)
- Disaccharides|*CS; Fucosyltransferases|*ME;
Oligosaccharides|*CS
- MeSH Heading
- Carbohydrate Sequence; Molecular Sequence Data; Support,
U.S. Gov't, P.H.S.
- Publication Type
- JOURNAL ARTICLE
- ISSN
- 0008-6215
- Country of Publication
- NETHERLANDS
Record 15 from database: MEDLINE
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- Title
- Biosynthesis of methylphosphomannosyl residues in the
oligosaccharides of Dictyostelium discoideum glycoproteins.
Evidence that the methyl group is derived from methionine.
- Author
- Freeze HH; Wolgast D
- Address
-
- Source
- J Biol Chem, 1986 Jan, 261:1, 135-41
- Abstract
- The phosphorylated oligosaccharides of Dictyostelium
discoideum contain methylphosphomannosyl residues which are
stable to mild-acid and base hydrolysis (Gabel, C. A.,
Costello, C. E., Reinhold, V. N., Kurtz, L., and Kornfeld,
S. (1984) J. Biol. Chem. 259, 13762-13769). Here we present
evidence that these methyl groups are derived from
[methyl-3H]methionine, in vivo and
[methyl-3H]S-adenosylmethionine in vitro. About 18% of the
macromolecules secreted from vegetative cells labeled with
[methyl-3H]methionine are released by digestion with
preparations of endoglycosidase/peptide N-glycosidase F. The
majority of the released molecules are sulfated, anionic
high mannose-type oligosaccharides. Strong acid hydrolysis
of the [3H]methyl-labeled molecules yields [3H]methanol with
kinetics of release similar to those found for the
generation of Man-6-P from chemically synthesized
methylphosphomannose methylglycoside. Treatment of the
[3H]methyl-labeled molecules with a phosphodiesterase from
Aspergillus niger which is known to cleave this
phosphodiester also releases [3H]methanol from a portion of
the oligosaccharides. In vitro incorporation of
[methyl-3H]S-adenosylmethionine into endogenous acceptors
found in membrane preparations shows that the [3H]methyl
group of the methylphosphomannose residues can be derived
from this molecule.
- Language of Publication
- English
- Unique Identifier
- 86085795
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- MeSH Heading (Major)
- Dictyostelium|*ME; Glycoproteins|*BI; Hexosephosphates|*BI;
Mannosephosphates|*BI; Methionine|*ME; Oligosaccharides|*BI
- MeSH Heading
- Chromatography, High Pressure Liquid; Chromatography, Ion
Exchange; Glycoside Hydrolases|ME; Hydrogen-Ion
Concentration; Kinetics; Methylation; Phosphorylation; S-Adenosylmethionine|ME;
Support, U.S. Gov't, P.H.S.
- Publication Type
- JOURNAL ARTICLE
- ISSN
- 0021-9258
- Country of Publication
- UNITED STATES
Record 16 from database: MEDLINE
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- Title
- Effects of methyl-group acceptors on the regulation of
plasma cholesterol level in rats fed high cholesterol diets.
- Author
- Sugiyama K; Ohishi A; Siyu H; Takeuchi H
- Address
- Department of Applied Biological Chemistry, Faculty of
Agriculture, Shizuoka University, Japan.
- Source
- J Nutr Sci Vitaminol (Tokyo), 1989 Dec, 35:6, 613-26
- Abstract
- The effects of methyl-group acceptors such as glycine,
guanidinoacetic acid, and nicotinamide on cholesterol
metabolism and phosphatidylcholine(PC) biosynthesis were
investigated with rats fed a 25% casein diet containing
cholesterol with or without methionine supplement. The
effect of ethanolamine, an indirect methyl-group acceptor
via phosphatidylethanolamine(PE) formation, was also
compared with those of methyl-group acceptors. The
methyl-group acceptors and ethanolamine decreased or tended
to decrease plasma total cholesterol level when added to the
25% casein diet. These compounds also significantly
depressed the methionine-induced enhancement of plasma
cholesterol level. The activity of PE N-methyltransferase
was decreased by the addition of glycine, guanidinoacetic
acid, and nicotinamide, but not ethanolamine, to the
reaction mixture when assayed using the postmitochondrial
fraction of liver homogenate, suggesting that PE N-methyltransferase
activity can be depressed by glycine N-methyltransferase,
guanidinoacetic acid N-methyltransferase, and nicotinamide
N-methyltransferase systems. The PE N-methyltransferase
activity in liver microsomes, however, did not decrease in
response to the dietary addition of methyl-group acceptors.
The in vitro incorporation of [CH3-14C]methionine into PC of
liver slices was also significantly inhibited by the
addition of glycine and nicotinamide, but not
guanidinoacetic acid and ethanolamine, to the incubation
medium. It is suggested that methyl-group acceptors can
decrease plasma cholesterol level at least in part through
the depression of PC biosynthesis via PE N-methylation
pathway, and that the mechanism for the plasma
cholesterol-lowering effect of ethanolamine is different
from that of methyl-group acceptors.
- Language of Publication
- English
- Unique Identifier
- 90237922
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- MeSH Heading (Major)
- Cholesterol|*BL; Cholesterol, Dietary|*AD/PD;
Glycine|*AA/*PD; Niacinamide|*PD
- MeSH Heading
- Animal; Bile Acids and Salts|ME; Caseins|AD; Comparative
Study; Dietary Proteins|AD; Ethanolamines|PD; Feces;
Lipids|ME; Liver|AH/DE/ME; Male; Methionine|AD/PD;
Methyltransferases|ME; Microsomes, Liver|EN; Organ Weight|DE;
Rats; Rats, Inbred Strains
- Publication Type
- JOURNAL ARTICLE
- ISSN
- 0301-4800
- Country of Publication
- JAPAN
Record 17 from database: MEDLINE
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- Title
- Reduced methyl group acceptance of
1-beta-D-arabinofuranosylcytosine-containing DNA polymers.
- Author
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