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Enzymatic in vitro glycosylation is possible using a reverse reaction of peptide-N-glycosidase F (PNGase F), and non-enzymatic in vitro glycosylation occurs when the sugar residue is one or two units long. To identify the differences between enzymatic and non-enzymatic glycosylation, glycosylation sites were analyzed by the acid hydrolysis of glycopeptides followed by MALDI-TOF mass spectrometric analysis. Pentapeptide (Arg-Lys-Asp-Val-Tyr) and octapeptide (Glu-Ile-Leu-Asp-Val-Pro-Ser-Thr) were used in this study, and the sequence of the octapeptide was appropriately chosen to investigate the specificity of enzymatic glycosylation by considering the characteristics of PNGase F and non-enzymatic glycosylation. N,N′-Diacetylchitobiose was aminated prior to the glycosylation reaction at an amination extent of 60%. The glycosylation site was very specific to the aspartate residue in the enzymatic reaction, while non-enzymatic glycosylation occurred at arginine or lysine residues. PNGases F can be effectively used for the glycosylation of the non-glycosylated recombinant proteins produced in prokaryotic cells. 相似文献
994.
Ronald Lindahl David W. Baggett Alvin L. Winter 《Biochimica et Biophysica Acta (BBA)/General Subjects》1985,843(3)
We have proposed developing rat hepatoma cell lines as an in vitro model for studying the regulation of changes in aldehyde dehydrogenase activity occurring duringhepatocarcinogenesis. Aldehyde dehydrogenase purified in a single step from HTC rat hepatoma cells is identical to the aldehyde dehydrogenase isolated from rat hepatocellular carcinomas. HTC aldehyde dehydrogenase is a 110 kDa dimer composed of 54-kDa subunits, prefers NADP+ as coenzyme, and preferentially oxidizes benzaldehyde-like aromatic aldehydes but not phenylacetaldehyde. The substrate and coenzyme specificity, effects of disulfiram, pH profile and isoelectric point of HTC aldehyde dehydrogenase are also identical to these same properties of the tumor aldehyde dehydrogenase. In immunodiffusions, both isozymes are recognized with complete identity by anti-HTC aldehyde dehydrogenase antibodies. Having established that HTC aldehyde dehydrogenase is very similar, if not identical, to the aldehyde dehydrogenase found in hepatocellular carcinomas, simplifies the development of molecular probes for examination of the regulation of tumor aldehyde dehydrogenase activity in vivo and in vitro. 相似文献
995.
Joo Young Huh Seulah Lee Eun-Bi Ma Hee Jeong Eom Jiwon Baek Yoon-Joo Ko 《Journal of enzyme inhibition and medicinal chemistry》2018,33(1):1167-1173
Betula platyphylla var. japonica (Betulaceae) has been used traditionally in Asian countries for the treatment of inflammatory diseases. A recent study has reported a phenolic compound, platyphylloside from B. platyphylla, that shows inhibition on adipocyte differentiation and induces lipolysis in 3T3-L1 cells. Based on this finding, we conducted phytochemical analysis of the EtOH extract of the bark of B. platyphylla var. japonica, which resulted in the isolation of phenolic glycosides (1–4). Treatment of the isolated compounds (1–4) during adipocyte differentiation of 3T3-L1 mouse adipocytes resulted in dose-dependent inhibition of adipogenesis. In mature adipocytes, arylbutanoid glycosides (2–4) induced lipolysis related genes HSL and ATGL, whereas catechin glycoside (1) had no effect. Additionally, arylbutanoid glycosides (2–4) also induced GLUT4 and adiponectin mRNA expression, indicating improvement in insulin signaling. This suggests that the isolates from B. platyphylla var. japonica exert benefial effects in regulation of adipocyte differentiation as well as adipocyte metabolism. 相似文献
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June Bryan de la Peña Irene Joy dela Peña Raly James Custodio Chrislean Jun Botanas Hee Jin Kim Jae Hoon Cheong 《Molecular neurobiology》2018,55(5):3739-3754
Attention-deficit/hyperactivity disorder (ADHD) is a common, behavioral, and heterogeneous neurodevelopmental condition characterized by hyperactivity, impulsivity, and inattention. Symptoms of this disorder are managed by treatment with methylphenidate, amphetamine, and/or atomoxetine. The cause of ADHD is unknown, but substantial evidence indicates that this disorder has a significant genetic component. Transgenic animals have become an essential tool in uncovering the genetic factors underlying ADHD. Although they cannot accurately reflect the human condition, they can provide insights into the disorder that cannot be obtained from human studies due to various limitations. An ideal animal model of ADHD must have face (similarity in symptoms), predictive (similarity in response to treatment or medications), and construct (similarity in etiology or underlying pathophysiological mechanism) validity. As the exact etiology of ADHD remains unclear, the construct validity of animal models of ADHD would always be limited. The proposed transgenic animal models of ADHD have substantially increased and diversified over the years. In this paper, we compiled and explored the validity of proposed transgenic animal models of ADHD. Each of the reviewed transgenic animal models has strengths and limitations. Some fulfill most of the validity criteria of an animal model of ADHD and have been extensively used, while there are others that require further validation. Nevertheless, these transgenic animal models of ADHD have provided and will continue to provide valuable insights into the genetic underpinnings of this complex disorder. 相似文献
999.
Suvarna H. Pagire Eunhye Lee Haushabhau S. Pagire Eun Jung Bae Soo Jung Ryu Dahye Lee Min Hee Kim Geum Ran Kim Kyu-Seok Hwang Sukyung Ahn Jin Hee Maeng Jin Sook Song Myung Ae Bae Don Hang Lee Jin Hee Ahn 《Bioorganic & medicinal chemistry letters》2018,28(3):529-532
A series of glutamic acid derivatives was synthesized and evaluated for their antioxidant activity and stability. We found several potent and stable glutamic acid derivatives. Among them, compound 12b exhibited good in vitro activity, chemical stability and cytotoxicity. A prototype compound 12b showed an anti-inflammatory effect in LPS-stimulated RAW 264.7 cell lines and in a zebrafish model. 相似文献
1000.
Kim Bong Jik Cho Sung Woo Jeon Yung Jin An Sujin Jo Ara Lim Jae Hyun Kim Dong-Young Won Tae-Bin Han Doo Hee Rhee Chae-Seo Kim Hyun Jik 《Applied microbiology and biotechnology》2018,102(1):105-115
Applied Microbiology and Biotechnology - We studied the contribution of Duox2 in mucosal host defense against influenza A virus (IAV) infection in in vivo lung. We found that Duox2 was required for... 相似文献