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The effect of lincocin (a plastid protein synthesis inhibitor) treatment on the greening process of bean (Phaseolus vulgaris L.) leaves have been studied. In comparison with control leaves treated ones had a decreased rate of chloroplast development. They had a marked chlorophyll deficiency and a decreased chlorophyll a/b ratio. Some long and short wavelength forms of chlorophyll a were lacking as evidenced from the absorption spectra at 25°C and the fluorescence spectra at 77°K. The –14CO2 fixation was inhibited by 80–90% in treated leaves. The fluorescence induced by the measuring light was greater in the treated leaves than in the control ones, and the kinetics of the decline of the relative fluorescence intensity were also different. Electron microscopic studies showed macrogranum-like structures and incomplete membrane vesicles in the treated plastids. After longer treatment a destruction of membranes was observed. The results indicate some structural and functional membrane deficiencies and instability of the membranes. 相似文献
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DIDIER FOURGON IGOR EECKHAUT DEVARAJEN VAÏTILINGON MICHEL JANGOUX 《Invertebrate reproduction & development.》2013,57(3):155-165
Summary The larval development of the ophiocomid ophiuroid Ophiomastix venosais described using SEM. The gastrula transforms into a uniformly ciliated early larva which progressively changes into a lecithotrophic late premetamorphic larva with a continuous bilateral ciliated band. This stage is short-lived and equivalent to a highly reduced ophiopluteus. Comparisons between O. venosa and other ophiuroid species whose development has been investigated suggest that, whatever the developmental mode (lecithotrophic or planktotrophic), a pluteus stage always occurs in ophiuroids with planktonic development. Two metamorphic stages were identified, the late metamorphic larva differing from the early one by the closure of the larval mouth. The appearance of the permanent mouth marks the end of the metamorphosis. The postlarva still possesses remnants of larval features. The transformation of the reduced ophiopluteus into a barrel-shaped metamorphic larva with transverse ciliated bands, a vitellaria larva, is followed. The possible occurrence of a unique type of metamorphic larva in non-brooding ophiuroids is discussed. Verification of this, however, needs further SEM investigations on metamorphic larva from species having “regular” planktotrophic development. 相似文献
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Sokolov AV Golenkina EA Kostevich VA Vasilyev VB Sud'ina GF 《Biochemistry. Biokhimii?a》2010,75(12):1464-1469
The interaction between ceruloplasmin (CP), the multicopper oxidase of human plasma, and 5-lipoxygenase (5-LO), the key enzyme
of leukotriene synthesis, is shown for the first time. By Western-blotting and mass spectrometry of tryptic fragments, it
is shown that 5-LO from protein extract of human leukocytes binds with immobilized CP. Dose-dependent influence of intact
CP on leukotrienes synthesis is found: CP reduced leukotrienes synthesis in leukocytes in a dose above 50 μg/ml (normal CP
concentration in plasma is about 300–400 μg/ml). Proteolyzed CP and apo-form of CP is unable to inhibit activity of 5-LO.
CP increased activity of 5-LO at low doses (5–10 μg/ml). On the whole, the influence of CP on phagocytosis index of leukocytes
coordinates with influence on activity of 5-LO: the index increased in the range of 2–10 μg/ml CP and decreased at doses of
CP above 40 μg/ml. The dual role of CP in regulation of cellular response of leukocytes is discussed. 相似文献
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Sokolov AV Ageeva KV Kostevich VA Berlov MN Runova OL Zakharova ET Vasilyev VB 《Biochemistry. Biokhimii?a》2010,75(11):1361-1367
This paper describes formation of complexes of ceruloplasmin (CP) with such proteins of the serprocidin family as azurocidin
(CAP37), neutrophilic elastase (NE), cathepsin G (CG), and proteinase 3 (PR3). We present evidence that serprocidins form
complexes with CP at a molar ratio 1: 1. Phenylmethylsulfonyl fluoride, a serine protease inhibitor, did not prevent the interaction
of serprocidins with CP in the course of SDS-free disc electrophoresis. CP affected the activities of NE, CG, and PR3 as a
competitive inhibitor with K
i ≈ 1 μM. Inhibitory effect of CP depended on ionic strength of the solution and was negligible at NaCl concentrations above
300 mM. In the mode of competitive inhibitors serprocidins suppressed oxidase activity of CP towards p-phenylenediamine. CAP37
displayed the strongest inhibitory effect (K
i ≈20 nM). Upon adding various serprocidins to human, rat, rabbit, dolphin, dog, horse, and mouse plasma only CAP37 would form
a complex with CP. Synthetic peptide RKARPRQFPRRR (5–13, 61–63 CAP37) displaced CAP37 from its complex with CP. Adding CAP37
to the triple complex formed by CP, lactoferrin, and myeloperoxidase resulted in displacement of the latter from the complex.
The dissociation constant of CAP37 with immobilized CP was 13 nM. Therefore, among serprocidins CAP37 can be regarded as the
specific partner of CP. 相似文献
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Nikolay A. Barinov Irina I. Vlasova Alexey V. Sokolov Valeria A. Kostevich Evgeniy V. Dubrovin Dmitry V. Klinov 《Biochimica et Biophysica Acta (BBA)/General Subjects》2018,1862(12):2862-2868
Background
Metalloproteins myeloperoxidase (MPO), ceruloplasmin (CP) and lactoferrin (LF) play an important role in regulation of inflammation and oxidative stress in vertebrates. It was previously shown that these proteins may work synergetically as antimicrobial and anti-inflammatory agents by forming complexes, such as MPO-CP and LF-CP. However, interaction of metalloprotein molecules with each other has never been characterized at a single-molecule level.Methods
In this study, the pairwise interactions of MPO, CP and LF molecules were investigated at a single-molecule level using high-resolution atomic force microscopy (AFM). Highly oriented pyrolytic graphite surface (HOPG) modified with oligoglycine-hydrocarbon graphite modifier (GM) was used as a substrate for protein deposition.Results
The procedure for reliable AFM investigation of metalloproteins and their complexes has been developed. Using this procedure, we have visualized, for the first time, single MPO, CP and LF molecules, characterized the morphology of MPO-CP and LF-CP complexes and confirmed the absence of direct contacts between MPO and LF molecules. Moreover, we have revealed the novel chainlike shape of MPO-CP conjugates.Conclusions
GM-HOPG was shown to be a convenient substrate for AFM investigation of metalloproteins and their complexes. Direct AFM visualization of MPO-CP and LF-CP complexes, on the one hand, complements previous data obtained from the “bulk techniques” and, on the other hand, provides new insight into the ultrastructure of MPO-CP complexes.General significance
The obtained results contribute to the better understanding of regulation of inflammation and oxidation stress mediated by collaborative action of the metalloproteins such as MPO, CP and LF. 相似文献8.
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D. V. Grigorieva I. V. Gorudko V. A. Kostevich A. V. Sokolov I. V. Buko V. B. Vasilyev L. Z. Polonetsky O. M. Panasenko S. N. Cherenkevich 《Biochemistry (Moscow) Supplemental Series B: Biomedical Chemistry》2016,10(2):173-179
A significant increase in the myeloperoxidase (MPO) activity has been found in plasma of patients with stable angina and with acute coronary syndrome (ACS) in comparison with the control group. MPO concentration was significantly increased in plasma of ACS patients. Reduced MPO activity in the treated ACS patients correlated with a favorable outcome of the disease. Generally, changes in plasma MPO concentration coincided with changes in lactoferrin concentration thus confirming the role of neutrophil degranulation in the increase of plasma concentrations of these proteins. The increase in MPO activity was obviously determined by modification of the MPO protein caused by reactive oxygen species and halogen in the molar ratio of 1: 25 and 1: 50. The decrease in plasma MPO activity may be associated with increased plasma concentrations of the physiological inhibitor of its activity, ceruloplasmin, and also with modification of the MPO protein with reactive oxygen species and halogen at their molar ratio of 1: 100 and higher. Thus, MPO activity may be used for evaluation of effectiveness of the treatment of cardiovascular diseases. 相似文献