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Ljubov Dzanaeva Barbara Kruk Justyna Ruchala Jens Nielsen Andriy Sibirny Kostyantyn Dmytruk 《Cell biology international》2020,44(8):1606-1615
Xylose is a second‐most abounded sugar after glucose in lignocellulosic hydrolysates and should be efficiently fermented for economically viable second‐generation ethanol production. Despite significant progress in metabolic and evolutionary engineering, xylose fermentation rate of recombinant Saccharomyces cerevisiae remains lower than that for glucose. Our recent study demonstrated that peroxisome‐deficient cells of yeast Ogataea polymorpha showed a decrease in ethanol production from xylose. In this work, we have studied the role of peroxisomes in xylose alcoholic fermentation in the engineered xylose‐utilizing strain of S. cerevisiae. It was shown that peroxisome‐less pex3Δ mutant possessed 1.5‐fold decrease of ethanol production from xylose. We hypothesized that peroxisomal catalase Cta1 may have importance for hydrogen peroxide, the important component of reactive oxygen species, detoxification during xylose alcoholic fermentation. It was clearly shown that CTA1 deletion impaired ethanol production from xylose. It was found that enhancing the peroxisome population by modulation the peroxisomal biogenesis by overexpression of PEX34 activates xylose alcoholic fermentation. 相似文献
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Dzanaeva Ljubov Kruk Barbara Ruchala Justyna Sibirny Andriy Dmytruk Kostyantyn 《Antonie van Leeuwenhoek》2021,114(9):1373-1385
Antonie van Leeuwenhoek - Lignocellulosic biomass is an attractive sustainable platform for fuel ethanol production. Xylose is a second after glucose most abounded sugar in lignocellulosic... 相似文献
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Ellyard JI Simson L Bezos A Johnston K Freeman C Parish CR 《The Journal of biological chemistry》2007,282(20):15238-15247
An important feature of chemokines is their ability to bind to the glycosaminoglycan (GAG) side chains of proteoglycans, predominately heparin and heparan sulfate. To date, all chemokines tested bind to immobilized heparin in vitro, as well as cell surface heparan sulfate in vitro and in vivo. These interactions play an important role in modulating the action of chemokines by facilitating the formation of stable chemokine gradients within the vascular endothelium and directing leukocyte migration, by protecting chemokines from proteolysis, by inducing chemokine oligomerization, and by facilitating transcytosis. Despite the importance of eotaxin in eosinophil differentiation and recruitment being well established, little is known about the interaction between eotaxin and GAGs and the functional consequences of such an interaction. Here we report that eotaxin binds selectively to immobilized heparin with high affinity (K(d) = 1.23 x 10(-8) M), but not to heparan sulfate or a range of other GAGs. The interaction of eotaxin with heparin does not promote eotaxin oligomerization but protects eotaxin from proteolysis directly by plasmin and indirectly by cathepsin G and elastase. In vivo, co-administration of eotaxin and heparin is able to significantly enhance eotaxin-mediated eosinophil recruitment in a mouse air-pouch model. Furthermore, when heparin is co-administered with eotaxin at a concentration that does not normally result in eosinophil infiltration, eosinophil recruitment occurs. In contrast, heparin does not enhance eotaxin-mediated eosinophil chemotaxis in vitro, suggesting protease protection or haptotactic gradient formation as the mechanism by which heparin enhances eotaxin action in vivo. These results suggest a role for mast cell-derived heparin in the recruitment of eosinophils, reinforcing Th2 polarization of inflammatory responses. 相似文献
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Simson L Ellyard JI Dent LA Matthaei KI Rothenberg ME Foster PS Smyth MJ Parish CR 《Journal of immunology (Baltimore, Md. : 1950)》2007,178(7):4222-4229
The role of the immune system in the surveillance of transformed cells has seen a resurgence of interest in the last 10 years, with a substantial body of data in mice and humans supporting a role for the immune system in host protection from tumor development and in shaping tumor immunogenicity. A number of earlier studies have demonstrated that eosinophils, when recruited into tumors, can very effectively eradicate transplantable tumors. In this study, we investigated whether eosinophils also play a role in tumor immune surveillance by determining the incidence of methylcholanthrene (MCA)-induced fibrosarcomas in IL-5 transgenic mice that have greatly enhanced levels of circulating eosinophils, CCL11 (eotaxin-1)-deficient mice that lack a key chemokine that recruits eosinophils into tissues, and the eosinophil-deficient mouse strains, IL-5/CCL11(-/-) and DeltadblGATA. It was found that MCA-induced tumor incidence and growth were significantly attenuated in IL-5 transgenic mice of both the BALB/c and C57BL/6 backgrounds. Histological examination revealed that the protective effect of IL-5 was associated with massively enhanced numbers of eosinophils within and surrounding tumors. Conversely, there was a higher tumor incidence in CCL11(-/-) BALB/c mice, which was associated with a reduced eosinophil influx into tumors. This correlation was confirmed in the eosinophil-deficient IL-5/CCL11(-/-) and DeltadblGATA mouse strains, where tumor incidence was greatly increased in the total absence of eosinophils. In addition, subsequent in vitro studies found that eosinophils could directly kill MCA-induced fibrosarcoma cells. Collectively, our data support a potential role for the eosinophil as an effector cell in tumor immune surveillance. 相似文献
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Alexander A. Krayevsky Ljubov S. Victorova Dmitrii Ju. Mozzherin Marina K. Kukhanova 《Nucleosides, nucleotides & nucleic acids》2013,32(1):83-93
Abstract O4′-Nor-2′,3′-dideoxy-2′,3′-didehydronucleoside 5′-triphosphates (acyclo-d4NTP) have been shown to have the properties of effective termination substrates for DNA biosynthesis, catalyzed by several different DNA polymerases. 相似文献
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Yuri M. Yevdokimov Sergey G. Skuridin Sergey V. Semenov Ljubov A. Dadinova Viktor I. Salyanov Efim I. Kats 《Journal of biological physics》2017,43(1):45-68
In this research, we observe and rationalize theoretically the transition from hexagonal to cholesteric packing of double-stranded (ds) DNA in dispersion particles. The samples were obtained by phase exclusion of linear ds DNA molecules from water-salt solutions of poly(ethylene glycol)—PEG—with concentrations ranging from 120 mg ml?1 to 300 mg ml?1. In the range of PEG concentrations from 120 mg ml?1 to 220 mg ml?1 at room temperature, we find ds DNA molecule packing, typical of classical cholesterics. The corresponding parameters for dispersion particles obtained at concentrations greater than 220 mg ml?1 indicate hexagonal packing of the ds DNA molecules. However, slightly counter-intuitively, the cholesteric-like packing reappears upon the heating of dispersions with hexagonal packing of ds DNA molecules. This transition occurs when the PEG concentration is larger than 220 mg ml?1. The obtained new cholesteric structure differs from the classical cholesterics observed in the PEG concentration range 120–220 mg ml?1 (hence, the term ‘re-entrant’). Our conclusions are based on the measurements of circular dichroism spectra, X-ray scattering curves and textures of liquid-crystalline phases. We propose a qualitative (similar to the Lindemann criterion for melting of conventional crystals) explanation of this phenomenon in terms of partial melting of so-called quasinematic layers formed by the DNA molecules. The quasinematic layers change their spatial orientation as a result of the competition between the osmotic pressure of the solvent (favoring dense, unidirectional alignment of ds DNA molecules) and twist Frank orientation energy of adjacent layers (favoring cholesteric-like molecular packing). 相似文献
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The molecular mechanism of action of the alkaloid lycorine has been revised. According to our results, lycorine inhibits the binding of CACCA-Leu←Ac to the donor site of the peptidyltranferase center of wheat-germ ribosomes, whereas the transpeptidation reaction in the system with the minimal model donor is not inhibited. The equilibrium constant of CACCA-Leu←Ac to the donor site of 80 S ribosomes is measured. 相似文献
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PalZ - Remains of a hynobiid salamanderRanodon cf.Sibiriens are reported from the Upper Pliocene (Early Villafranchian, mammal zone MN 16) of the Zaili Alatau Range, southern Kazakhstan. Vertebrae... 相似文献
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