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221.
Lipase A from Candida antarctica (CALA, commercialized as Novocor ADL) was immobilized on octyl-agarose, which is a very useful support for lipase immobilization, and coated with polyethylenimine to improve the stability. The performance was compared to that of the form B of the enzyme (CALB) immobilized on the same support, as both enzymes are among the most popular ones used in biocatalysis. CALA immobilization produced a significant increase in enzyme activity vs. p-nitrophenyl butyrate (pNPB) (by a factor of seven), and the coating with PEI did not have a significant effect on enzyme activity. CALB reduced its activity slightly after enzyme immobilization. Octyl-CALA was less stable than octyl-CALB at pH 9 and more stable at pH 5 and, more clearly, at pH 7. PEI coating only increased octyl-CALA stability at pH 9. In organic solvents, CALB had much better stability in methanol and was similarly stable in acetonitrile or dioxane. In these systems, the PEI coating of octyl-CALA permitted some stabilization. While octyl-CALA was more active vs. pNPB, octyl-CALB was much more active vs. mandelic esters or triacetin. Thus, depending on the specific reaction and the conditions, CALA or CALB may offer different advantages and drawbacks. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 35: e2735, 2019 相似文献
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Evgenia A. Markova Nikolay G. Smirnov Tatyana P. Kourova Yuliya E. Kropacheva 《Mammalian Biology》2013,78(4):251-257
In order to reveal patterns of ontogenetic change in occlusal shape of evergrowing molars in arvicolines, an intravital tooth printing method was applied to 20 individuals of Microtus gregalis born in captivity. Complexity patterns of the first lower molar were assessed by morphotype analysis of the anteroconid complex. Morphotype dental patterns were monitored using tooth prints at 0.5, 1, 2, 3 months of age, and postmortem. Ontogenetic changes in molar complexity and bilateral symmetry among right and left molars of the same individual during the process of tooth wear were assessed. Our results suggested that morphotype dental patterns could not be clearly established in half-month old animals due to presence of juvenile characters. For animals of 1 month and older, age differences in morphotype dental patterns were non-significant and negligible compared to among-individual variation. Within-individual differences among right and left molars, when present, were not related to age of an animal suggesting that bilateral asymmetry of morphotype dental pattern could be regarded as inherent characteristic of an individual persisting during post-juvenile tooth wear. 相似文献
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Yuliya V. Katlinskaya Kanstantsin V. Katlinski Audrey Lasri Ning Li Daniel P. Beiting Amy C. Durham Ting Yang Eli Pikarsky Christopher J. Lengner F. Brad Johnson Yinon Ben-Neriah Serge Y. Fuchs 《Molecular and cellular biology》2016,36(7):1124-1135
Wnt pathway-driven proliferation and renewal of the intestinal epithelium must be tightly controlled to prevent development of cancer and barrier dysfunction. Although type I interferons (IFN) produced in the gut under the influence of microbiota are known for their antiproliferative effects, the role of these cytokines in regulating intestinal epithelial cell renewal is largely unknown. Here we report a novel role for IFN in the context of intestinal knockout of casein kinase 1α (CK1α), which controls the ubiquitination and degradation of both β-catenin and the IFNAR1 chain of the IFN receptor. Ablation of CK1α leads to the activation of both β-catenin and IFN pathways and prevents the unlimited proliferation of intestinal epithelial cells despite constitutive β-catenin activity. IFN signaling contributes to the activation of the p53 pathway and the appearance of apoptotic and senescence markers in the CK1α-deficient gut. Concurrent genetic ablation of CK1α and IFNAR1 leads to intestinal hyperplasia, robust attenuation of apoptosis, and rapid and lethal loss of barrier function. These data indicate that IFN play an important role in controlling the proliferation and function of the intestinal epithelium in the context of β-catenin activation. 相似文献
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Nataliya R. Rovnyagina Gleb S. Budylin Pavel V. Dyakonov Yuri M. Efremov Marina M. Lipina Yuliya R. Goncharuk Emirkhan E. Murdalov David A. Pogosyan Denis A. Davydov Alexander A. Korneev Natalia B. Serejnikova Karen A. Mikaelyan Stanislav A. Evlashin Vladimir A. Lazarev Alexey V. Lychagin Peter S. Timashev Evgeny A. Shirshin 《Journal of biophotonics》2023,16(3):e202200149
Osteoarthritis (OA) is one of the most common joint diseases worldwide. Unfortunately, clinical methods lack the ability to detect OA in the early stages. Timely detection of the knee joint degradation at the level of tissue changes can prevent its progressive damage. Here, diffuse reflectance spectroscopy (DRS) in the NIR range was used to obtain optical markers of the cartilage damage grades and to assess its mechanical properties. It was observed that the water content obtained by DRS strongly correlates with the cartilage thickness (R = .82) and viscoelastic relaxation time (R = .7). Moreover, the spectral parameters, including water content (OH-band), protein content (CH-band), and scattering parameters allowed for discrimination between the cartilage damage grades (10−4 < P ≤ 10−3). The developed approach may become a valuable addition to arthroscopy, helping to identify lesions at the microscopic level in the early stages of OA and complement the surgical analysis. 相似文献
226.
Deeva Anna A. Glukhova Ksenia A. Isoyan Lala S. Okulova Yuliya D. Uversky Vladimir N. Melnik Bogdan S. 《The protein journal》2022,41(2):304-314
The Protein Journal - Ice-binding proteins are expressed in the cells of some cold adapted organisms, helping them to survive at extremely low temperatures. One of the problems in studying such... 相似文献