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1.
EA Dukhanina TI Lukyanova EA Romanova V Guerriero NV Gnuchev GP Georgiev DV Yashin LP Sashchenko 《Cell cycle (Georgetown, Tex.)》2015,14(22):3635-3643
PGRP-S (Tag7) is an innate immunity protein involved in the antimicrobial defense systems, both in insects and in mammals. We have previously shown that Tag7 specifically interacts with several proteins, including Hsp70 and the calcium binding protein S100A4 (Mts1), providing a number of novel cellular functions. Here we show that Tag7–Mts1 complex causes chemotactic migration of lymphocytes, with NK cells being a preferred target. Cells of either innate immunity (neutrophils and monocytes) or acquired immunity (CD4+ and CD8+ lymphocytes) can produce this complex, which confirms the close connection between components of the 2 branches of immune response. 相似文献
2.
A. V. Kalinovich N. V. Azarkina T. V. Vygodina T. Soulimane A. A. Konstantinov 《Biochemistry. Biokhimii?a》2010,75(3):342-352
Cytochrome c oxidase of the ba
3-type from Thermus thermophilus does not interact with cyanide in the oxidized state and acquires the ability to bind heme iron ligands only upon reduction.
Cyanide complexes of the reduced heme a
3 in cytochrome ba
3 and in mitochondrial aa
3-type cytochrome oxidase are similar spectroscopically, but the a
32+-CN complex of cytochrome ba
3 is strikingly tight. Experiments have shown that the K
d value of the cytochrome ba
3 complex with cyanide in the presence of reductants of the enzyme binuclear center does not exceed 10−8 M, which is four to five orders of magnitude less than the K
d of the cyanide complex of the reduced heme a
3 of mitochondrial cytochrome oxidase. The tightness of the cytochrome ba
3 complex with cyanide is mainly associated with an extremely slow rate of the ligand dissociation (k
off ≤ 10−7 sec−1), while the rate of binding (k
on ∼ 102 M−1·sec−1) is similar to the rate observed for the mitochondrial cytochrome oxidase. It is proposed that cyanide dissociation from
the cytochrome ba
3 binuclear center might be hindered sterically by the presence of the second ligand molecule in the coordination sphere of
CuB2+. The rate of cyanide binding with the reduced heme a
3 does not depend on pH in the neutral area, but it approaches linear dependence on H+ activity in the alkaline region. Cyanide binding appears to be controlled by protonation of an enzyme group with pK
a = 8.75. 相似文献
3.
In this work, high ΔμH+-dependent succinate oxidase activity has been demonstrated for the first time with membrane vesicles isolated from Bacillus subtilis. The maximal specific rate of succinate oxidation by coupled inside-out membrane vesicles isolated from a B. subtilis strain overproducing succinate:menaquinone oxidoreductase approaches the specific rate observed with the intact cells. Deenergization
of the membrane vesicles with ionophores or alamethicin brings about an almost complete inhibition of succinate oxidation.
An apparent K
m for succinate during the energy-dependent succinate oxidase activity of the vesicles (2.2 mM) is higher by an order of magnitude
than the K
m value measured for the energy-independent reduction of 2,6-dichlorophenol indophenol. The data reveal critical importance
of ΔμH+ for maintaining active electron transfer by succinate:menaquinone oxidoreductase. The role of ΔμH+ might consist in providing energy for thermodynamically unfavorable menaquinone reduction by succinate by virtue of transmembrane
electron transport within the enzyme down the electric field; alternatively, ΔμH+ could play a regulatory role by maintaining the electroneutrally operating enzyme in a catalytically active conformation. 相似文献
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5.
An investigation of the spatiotemporal management of the ground-dwelling spider community has been carried out at the continuous habitat gradient from the forest outlier center to the meadowland center in the southern part of the forest-steppe zone of Novosibirsk oblast in 2007?2008. We apply two sampling methods which complete each other: pitfall trapping and hand separation of soil samples. Eighty-three species of spiders from 14 families are determined. Spiders are most abundant in the early summer and less abundant in the middle of summer. Representatives of different families are of maximum abundance in different sites: Lycosidae and Gnaphosidae mainly in the forest and Philodromidae in the solonetz meadow. The distribution of diversity and abundance of spiders and ground beetles throughout the habitat gradient are generally similar. This is contradictory to the spatial interactions of these two groups in Arctic and extreme ecosystems. Niche distinguishing between ground beetles and spider species is not only topical. It includes the usage of different strata of vegetation, various seasonal activity, and trophic specialization. 相似文献
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We present an efficient computational architecture designed using supervised machine learning model to predict amyloid fibril
forming protein segments, named AmylPepPred. The proposed prediction model is based on bio-physio-chemical properties of
primary sequences and auto-correlation function of their amino acid indices. AmylPepPred provides a user friendly web interface
for the researchers to easily observe the fibril forming and non-fibril forming hexmers in a given protein sequence. We expect that
this stratagem will be highly encouraging in discovering fibril forming regions in proteins thereby benefit in finding therapeutic
agents that specifically aim these sequences for the inhibition and cure of amyloid illnesses.
Availability
AmylPepPred is available freely for academic use at www.zoommicro.in/amylpeppred 相似文献9.
V A Berezin G M Shevchenko L I Ga?dar T I Zuban' V V Azarkina 《Biokhimii?a (Moscow, Russia)》1988,53(10):1745-1753
Soluble and membrane-bound neurospecific Con A-binding glycoproteins from human brain and tumours were identified and characterized, using a procedure which included stepwise extraction with low and high ionic strength buffers, buffered. Triton X-100 and sodium deoxycholate followed by ConA-Sepharose column chromatography, SDS-PAAG electrophoresis and immunoblotting. Adsorbed antisera against different types of neurospecific glycoproteins were used. The bulk of neurospecific glycoproteins (11 and 13) were revealed in protein fractions extracted with low ionic strength buffers and Triton X-100. In astrocytomas and glyoblastomas, some neurospecific glycoproteins were absent. Some glycoproteins were found in tumours, but were absent in brain tissue. Soluble, 77 kD glycoprotein, 11 and 16 kD glycoproteins solubilized with high ionic strength buffers and intrinsic membrane-bound 51, 57, 61, 74 and 77 kD glycoproteins can be viewed as stable neurospecific markers in malignant brain tumours. 相似文献