Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: UNIPROT:P06889 (
Mol
)
630,302
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
1. The metabolism of oxygen by phagocytosing neutrophils was traced by using 15O2. 2. The isotope did not exchange with the incubation medium or cells to an appreciable extent and unmetabolized oxygen was readily eluted by gassing the cell suspension. 3. The polarographic measurements of oxygen consumption closely paralleled the recovery of metabolized 15O2. 4. Almost all the metabolized 15O2 was converted into
water
, both in the presence and absence of KCN, supporting the concept that the oxygen consumed by neutrophils is converted into H2O2. It is unlikely that an appreciable proportion of this oxygen is incorporated into the organic composition of the cell or of the ingested micro-organism.
Clin Sci
Mol
Med 1978 Oct
PMID:Tracing the fate of oxygen consumed during phagocytosis by human neutrophils with 15O2. 71 56
The aggregated forms of protochlorophyll a (PChl), 4-vinyl-protochlorophyll a (4VPChl) and chlorophyll a (Chl) in binar mixtures of dioxane-
water
was investigated. The aggregates are oligomer particles of pigment molecules having considerable degrees of fluorescence polarisation which points to their ordered structure. Two types of fluorescent associates I and II have been discovered. By its electronic spectrum I is similar to the molecular pigment but has smaller quantum yield B congruent to 10(-2) and the lifetime of fluorescence tau congruent to 3--4.10(-9) sec. Associates of type I spontaneously transform into associates of type II which have narrower bands of electronic spectrum than the monomer, very low B congruent to 10(-3)--10(-4) and tau congruent to 2--4.10(-10) sec. In contrast with the decreasing of B and the band intensities in CD spectrum conditioned by rotational strength increase by factor of 100 under transformation from I to II. It follows from these data that the antibatic connection possibly exists between excitation deactivation in associates and their optical activity. From data on splitting the associate CD spectra of type I and II the excitation interaction energy V12 congruent to 75 cm-1 was estimated. The reasons of increasing of rotational strength under transformation from I to II and the overturn of the sign dependence of bands in CD spectrum in some cases are discussed.
Mol
Biol (Mosk)
PMID:[Spectral-luminescent properties of separate aggregated forms of pigments in solutions]. 73 87
A new molecular mechanism of muscle contraction is considered based on the cyclochelate oxyphosphorane structure of the long-lived intermediate in myosin-catalyzed ATP. Mg hydrolysis proposed earlier by the author. The mechanism implies the steric cleavage of the actomyosin bond by the gamma-phosphoryl group of ATP.Mg tightly binding to myosin; the myosin-catalyzed addition of
water
to the gamma-phosphoryl group to give oxyphosphorane group which sterically allows the formation of a more weak bent (deformed) actomyosin bond; the actin-catalyzed breakdown of the tightly bound oxyphosphorane intermediate into weakly bound products; the straightening of the bent actomyosin bond with the active change of an angle of myosin head attachment, the liberation of the weakly bound products and the displacement of the actin filament. The data are given in favour of an oxyphosphorane structure of the long-lived intermediate.
Mol
Biol (Mosk)
PMID:[Molecular mechanism of muscle contraction: the straightening of the bent actomyosin bond]. 73 89
Surface activity of cardiotoxin from the venom of cobra Naia naja oxiana and an acetylated analog of the cardiotoxin was investigated on the
water
-air interface. The interaction of these substances with lipid monolayers and bimolecular membrane was also studied. It was shown that on the
water
-air interface cardiotoxin can form two different types of monolayers with different conformations of molecules. Cardiotoxin is found to form complexes with phospholipids due to interaction of positive charges of amino groups of lysin with phosphate groups of lipid molecules. One molecule of toxin is able to complex up to 10 molecules of lipid. The complex formed has a high surface activity, much more than that of the pure protein. Cardiotoxin increases the anion conductivity of bimolecular membranes. The nature of this phenomen is studied. A hypothetical mechanism of biological activity of caridotoxin is offered. It is supposed that not cardiotoxin as that, but its complex with phospholipid is the active agent.
Mol
Biol (Mosk)
PMID:[Interaction of cardiotoxin from the venom of the cobra Naja naja oxiana with phospholipid membrane model systems]. 73 93
The rate of 1H leads to 3H exchange between
water
and C(8)H-groups of purinic residues in synthetic polynucleotides in wide temperature range measured. At temperatures below their Tm the rate of the exchange is shown to be lower as compared with that in corresponding mononucleotides. In the case of polynucleotides of A-conformation (poly(A).poly(U), poly(A).2poly(U) and poly(dA).2poly(dT), and poly(G).poly(C) the exchange is retarded by a factor of 5.7--7.5, whereas in the case of those of B-conformation (poly(dA).poly(dT), poly(dA--dT).poly(dA--dT) and poly(dG).poly(dC)) the exchange is retarded only by a factor of 2.3--2.5. Assuming the ylide mechanism of exchange the retardation is interpreted as a consequence of sterical hidrance in polynucleotides helical structure, which hampers contacts between purinic C(8)H-groups and OH-ions of solvent. Analysis of atomic arrangement around C(8)H-group and interatomic distances calculated on the basis of published atomic coordinates support our general conclusion that the sterical hindrance is more significant in the A-form as compared with that in the B-form. Elucidated correlation between the degree of the retardation in purine-containing polynucleotides and their conformation in solution allows to estimatf the type of conformation of polynucleotide with unknown structure on account of the slow 1H leads to 3H exchange data.
Mol
Biol (Mosk)
PMID:[Comparative study of slow 1H to 3H exchange in synthetic polynucleotides of A- and B-type conformations]. 73 99
The secondary structure of DNA is known to be largely determined by the kind of counterion bound to it. We have used the X-ray diffraction method to study the structure of magnesium and lithium salts of T2 phage DNA in oriented fibres. The structural behaviour of this glucosylated DNA in the form of magnesium and lithium salts was shown to be identical to the behaviour of the same salts of "normal" calf thymus DNA throughout the studied range of relative humidities (44-95%). However these two DNAs in the form of sodium salt are known to behave quite differently. One can presume that Mg2+ and Li+ influence the structural behaviour of double-stranded DNA so effectively as to be able to "ignore" the fact that T2 phage DNA contains glucoside residues. The results of this work and the already known facts concerning the structure of DNA in the form of various cation salts (in solution and in "solid" fibres) indicate that the structural behaviour of double-stranded DNA is mainly determined by the cation located in the region of the narrow groove of the double helix. If cations are graded according to the efficiency of their influence on the structural behaviour of DNA in fibres, the scale will coincide with that of their DNA-binding strength in
water
solution, that is: Mg2+ greater than Li+ greater than Na+ greater than K+ greater than Rb+. A qualitative consideration of electrostatic interaction between the cations and the negatively charged DNA strands leads one to suppose that this interaction must obstruct the transition of individual DNA molecules from the B-form to the A-form. Aggregation of self-aggregation of DNA molecules is presumed necessary to enable them to adopt the A-conformation.
Mol
Biol (Mosk)
PMID:[Investigation of the structure of magnesium and lithium salts of T2 phage DNA by the method of x-ray diffraction. The possible mechanisms of the participation of cations in the structural transformation of double-stranded DNA]. 74 8
1. Standard radioisotope dilution techniques employing [3H]
water
and [22Na]sodium chloride have been used to determine the total body
water
and total exchangeable sodium of 20 male and 10 female normal Ghanaians (Africans) aged 19--25 years. 2. Lean body mass and total body fat are calculated as a percentage of body weight; the total exchangeable sodium values have been expressed in relation to lean body mass. 3. Comparison of the data for Ghanaian subjects with published figures for Caucasian subjects of similar age shows that the Ghanaian men have much less total body fat and the women a little less total body fat than their Caucasian counterparts. 4. Total exchangeable sodium expressed in terms of lean body mass shows close agreement in both men and women.
Clin Sci
Mol
Med 1978 May
PMID:Total body water, total exchangeable sodium and related variables in the Ghanaian. 75 Jan 48
1. In rats deprived of food and
water
for 24 h acute renal failure was produced by the intramuscular injection of glycerol. Eight hours later plasma urea concentration had increased threefold despite a small rise in urine volume. Plasma concentrations of renin and renin substrate were elevated. 2. When saralasin, a competitive antagonist of angiotensin II, was infused for 8 h after glycerol injection, urine volume and plasma urea were similar to values in rats that had received an infusion of saline. 3. Administration of rat serum (4.5 ml h-1 kg-1) for 4 h suppressed plasma renin concentrations, but plasma urea increased to the same extent as in rats without serum. 4. When saralasin and serum were infused at the same time, urine volume, urine osmolality and solute excretion increased and the rise of plasma urea was diminished. 5. Saralasin has a protective effect against glycerol-induced acute renal failure only when volume is replaced concomitantly.
Clin Sci
Mol
Med 1978 May
PMID:Effect of saralasin and serum in myohaemoglobinuric acute renal failure of rats. 75 Jan 57
1. In a preparation of human leucocytes maintained in tissue culture fluid, increasing the extracellular zinc concentration leads to a significant increase in both ouabain-sensitive sodium efflux and in sodium influx. 2. Cell
water
and sodium content do not alter significantly with increasing extracellular zinc concentration. 3. A small increase in the ouabain-insensitive sodium efflux can be demonstrated when the external zinc concentration is raised from 0.75 mumol/l to 90 mumol/l.
Clin Sci
Mol
Med 1978 May
PMID:Effect of zinc on leucocyte sodium transport in vitro. 75 Jan 60
The experimental data indicating that the amplitude of the negative band in CD spectra of DNA compact particles forming in PEG-containing
water
-salt solutions intensifies with the decrease of DNA molecular weight are presented. This effect is not explained by the light scattering on the compact particles. The presence of the negative band in CD spectrum of DNA compact particles is interpreted as result of formation of dichrographic-active "microcrystalline" region ("domains") (if DNA compact particles are formed from double-stranded molecules with unaltered secondary structure); it is also supposed that the number of these regions in the particle and their dichrographic activity doesn't depend on the particles size. This interpretation is in agreement with experimental data on the increase of the number of compact particles with the decrease of DNA molecular weight. Proportionality coefficient in the linear dependence of the amplitude of negative band on the size of DNA compact particles in solution depends apparently on dichrographic activity of "microcrystalline" regions, and this activity is connected with structural peculiarities of initial DNA molecules.
Mol
Biol (Mosk)
PMID:[Compact form of DNA in solution. X. Peculiarities of circular dichroism spectra of DNA compact particles forming polyethylene glycol-containing water-salt solutions]. 75 78
<< Previous
1
2
3
4
5
6
7
8
9
10