Log in

Relevant bibliographies by topics / Serine octamers / Journal articles

Journal articles on the topic 'Serine octamers'

To see the other types of publications on this topic, follow the link: Serine octamers.

Author: Grafiati

Published: 10 December 2022

Last updated: 28 January 2023

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the top 50 journal articles for your research on the topic 'Serine octamers.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Browse journal articles on a wide variety of disciplines and organise your bibliography correctly.

1

Nanita, Sergio C., and R. Graham Cooks. "Negatively-Charged Halide Adducts of Homochiral Serine Octamers." Journal of Physical Chemistry B 109, no. 10 (March 2005): 4748–53. http://dx.doi.org/10.1021/jp046653+.

Full text

APA, Harvard, Vancouver, ISO, and other styles

2

Takats, Zoltan, Sergio C. Nanita, Gitta Schlosser, Karoly Vekey, and R. Graham Cooks. "Atmospheric Pressure Gas-Phase H/D Exchange of Serine Octamers." Analytical Chemistry 75, no. 22 (November 2003): 6147–54. http://dx.doi.org/10.1021/ac034284s.

Full text

APA, Harvard, Vancouver, ISO, and other styles

3

Nanita, Sergio C., and R. Graham Cooks. "Serine Octamers: Cluster Formation, Reactions, and Implications for Biomolecule Homochirality." Angewandte Chemie International Edition 45, no. 4 (January 16, 2006): 554–69. http://dx.doi.org/10.1002/anie.200501328.

Full text

APA, Harvard, Vancouver, ISO, and other styles

4

Liao, Guanhua, Yijie Yang, and Xianglei Kong. "Chirality effects on proline-substituted serine octamers revealed by infrared photodissociation spectroscopy." Phys. Chem. Chem. Phys. 16, no. 4 (2014): 1554–58. http://dx.doi.org/10.1039/c3cp53469c.

Full text

APA, Harvard, Vancouver, ISO, and other styles

5

Yan, C., and T. Mélèse. "Multiple regions of NSR1 are sufficient for accumulation of a fusion protein within the nucleolus." Journal of Cell Biology 123, no. 5 (December 1, 1993): 1081–91. http://dx.doi.org/10.1083/jcb.123.5.1081.

Full text

Abstract:

NSR1, a 67-kD nucleolar protein, was originally identified in our laboratory as a nuclear localization signal binding protein, and has subsequently been found to be involved in ribosome biogenesis. NSR1 has three regions: an acidic/serine-rich NH2 terminus, two RNA recognition motifs, and a glycine/arginine-rich COOH terminus. In this study we show that NSR1 itself has a bipartite nuclear localization sequence. Deletion of either basic amino acid stretch results in the mislocation of NSR1 to the cytoplasm. We further demonstrate that either of two regions, the NH2 terminus or both RNA recognition motifs, are sufficient to localize a bacterial protein, beta-galactosidase, to the nucleolus. Intensive deletion analysis has further defined a specific acidic/serine-rich region within the NH2 terminus as necessary for nucleolar accumulation rather than nucleolar targeting. In addition, deletion of either RNA recognition motif or point mutations in one of the RNP consensus octamers results in the mislocalization of a fusion protein within the nucleus. Although the glycine/arginine-rich region in the COOH terminus is not sufficient to bring beta-galactosidase to the nucleolus, our studies show that this domain is necessary for nucleolar accumulation when an RNP consensus octamer in one of the RNA recognition motifs is mutated. Our findings are consistent with the notion that nucleolar localization is a result of the binding interactions of various domains of NSR1 within the nucleolus rather than the presence of a specific nucleolar targeting signal.

APA, Harvard, Vancouver, ISO, and other styles

6

Vandenbussche, Sophie, Guy Vandenbussche, Jacques Reisse, and Kristin Bartik. "Do Serine Octamers Exist in Solution? Relevance of this Question in the Context of the Origin of Homochirality on Earth." European Journal of Organic Chemistry 2006, no. 14 (July 2006): 3069–73. http://dx.doi.org/10.1002/ejoc.200600370.

Full text

APA, Harvard, Vancouver, ISO, and other styles

7

Criglar, Jeanette M., Ramakrishnan Anish, Liya Hu, Sue E. Crawford, Banumathi Sankaran, B. V. Venkataram Prasad, and Mary K. Estes. "Phosphorylation cascade regulates the formation and maturation of rotaviral replication factories." Proceedings of the National Academy of Sciences 115, no. 51 (December 3, 2018): E12015—E12023. http://dx.doi.org/10.1073/pnas.1717944115.

Full text

Abstract:

The rotavirus (RV) genome is replicated and packaged into virus progeny in cytoplasmic inclusions called viroplasms, which require interactions between RV nonstructural proteins NSP2 and NSP5. How viroplasms form remains unknown. We previously found two forms of NSP2 in RV-infected cells: a cytoplasmically dispersed dNSP2, which interacts with hypophosphorylated NSP5; and a viroplasm-specific vNSP2, which interacts with hyperphosphorylated NSP5. Other studies report that CK1α, a ubiquitous cellular kinase, hyperphosphorylates NSP5, but requires NSP2 for reasons that are unclear. Here we show that silencing CK1α in cells before RV infection resulted in (i) >90% decrease in RV replication, (ii) disrupted vNSP2 and NSP5 interaction, (iii) dispersion of vNSP2 throughout the cytoplasm, and (iv) reduced vNSP2 protein levels. Together, these data indicate that CK1α directly affects NSP2. Accordingly, an in vitro kinase assay showed that CK1α phosphorylates serine 313 of NSP2 and triggers NSP2 octamers to form a lattice structure as demonstrated by crystallographic analysis. Additionally, a dual-specificity autokinase activity for NSP2 was identified and confirmed by mass spectrometry. Together, our studies show that phosphorylation of NSP2 involving CK1α controls viroplasm assembly. Considering that CK1α plays a role in the replication of other RNA viruses, similar phosphorylation-dependent mechanisms may exist for other virus pathogens that require cytoplasmic virus factories for replication.

APA, Harvard, Vancouver, ISO, and other styles

8

Jordan, Jacob S., and Evan R. Williams. "Dissociation of large gaseous serine clusters produces abundant protonated serine octamer." Analyst 146, no. 8 (2021): 2617–25. http://dx.doi.org/10.1039/d1an00273b.

Full text

APA, Harvard, Vancouver, ISO, and other styles

9

Takáts, Zoltán, and R. Graham Cooks. "Thermal formation of serine octamer ions." Chem. Commun., no. 4 (2004): 444–45. http://dx.doi.org/10.1039/b316768b.

Full text

APA, Harvard, Vancouver, ISO, and other styles

10

Scutelnic, Valeriu, Marta A. S. Perez, Mateusz Marianski, Stephan Warnke, Aurelien Gregor, Ursula Rothlisberger, Michael T. Bowers, et al. "The Structure of the Protonated Serine Octamer." Journal of the American Chemical Society 140, no. 24 (April 11, 2018): 7554–60. http://dx.doi.org/10.1021/jacs.8b02118.

Full text

APA, Harvard, Vancouver, ISO, and other styles

11

Takats, Zoltan, Sergio C. Nanita, and R. Graham Cooks. "Serine Octamer Reactions: Indicators of Prebiotic Relevance." Angewandte Chemie International Edition 42, no. 30 (August 4, 2003): 3521–23. http://dx.doi.org/10.1002/anie.200351210.

Full text

APA, Harvard, Vancouver, ISO, and other styles

12

Jordan, Jacob S., and Evan R. Williams. "Homochiral preference of serine octamer in solution and formed by dissociation of large gaseous clusters." Analyst 146, no. 22 (2021): 6822–30. http://dx.doi.org/10.1039/d1an01646f.

Full text

APA, Harvard, Vancouver, ISO, and other styles

13

Jordan, Jacob S., and Evan R. Williams. "Homochiral preference of serine octamer in solution and formed by dissociation of large gaseous clusters." Analyst 146, no. 22 (2021): 6822–30. http://dx.doi.org/10.1039/d1an01646f.

Full text

APA, Harvard, Vancouver, ISO, and other styles

14

Spencer, Emily A. C., Tony Ly, and Ryan R. Julian. "Formation of the serine octamer: Ion evaporation or charge residue?" International Journal of Mass Spectrometry 270, no. 3 (March 2008): 166–72. http://dx.doi.org/10.1016/j.ijms.2007.12.011.

Full text

APA, Harvard, Vancouver, ISO, and other styles

15

Ferreira da Silva, Filipe, Peter Bartl, Stephan Denifl, Tilmann D. MÃ¤rk, Andrew M. Ellis, and Paul Scheier. "Formation of the Magic L-Serine Octamer in Helium Nanodroplets." ChemPhysChem 11, no. 1 (January 18, 2010): 90–92. http://dx.doi.org/10.1002/cphc.200900826.

Full text

APA, Harvard, Vancouver, ISO, and other styles

16

Koch, Kim J., Duxi Zhang, R. Graham Cooks, Fabio C. Gozzo, and Marcos N. Eberlin. "Serine octamer metaclusters: formation, structure elucidation and implications for homochiral polymerization." Chemical Communications, no. 18 (2001): 1854–55. http://dx.doi.org/10.1039/b107148n.

Full text

APA, Harvard, Vancouver, ISO, and other styles

17

Seo, Jongcheol, Stephan Warnke, Kevin Pagel, Michael T. Bowers, and Gert von Helden. "Infrared spectrum and structure of the homochiral serine octamer–dichloride complex." Nature Chemistry 9, no. 12 (July 10, 2017): 1263–68. http://dx.doi.org/10.1038/nchem.2821.

Full text

APA, Harvard, Vancouver, ISO, and other styles

18

Kong, Xianglei, Cheng Lin, Giuseppe Infusini, Han-Bin Oh, Honghai Jiang, Kathrin Breuker, Chih-Che Wu, Oleg P. Charkin, Huan-Cheng Chang, and Fred W. McLafferty. "Numerous Isomers of Serine Octamer Ions Characterized by Infrared Photodissociation Spectroscopy." ChemPhysChem 10, no. 15 (October 19, 2009): 2603–6. http://dx.doi.org/10.1002/cphc.200900564.

Full text

APA, Harvard, Vancouver, ISO, and other styles

19

Takats, Zoltan, Sergio C. Nanita, and R. Graham Cooks. "Titelbild: Serine Octamer Reactions: Indicators of Prebiotic Relevance (Angew. Chem. 30/2003)." Angewandte Chemie 115, no. 30 (August 4, 2003): 3565. http://dx.doi.org/10.1002/ange.200390570.

Full text

APA, Harvard, Vancouver, ISO, and other styles

20

Julian, Ryan R., Robert Hodyss, Brian Kinnear, Martin F. Jarrold, and J. L. Beauchamp. "Nanocrystalline Aggregation of Serine Detected by Electrospray Ionization Mass Spectrometry: Origin of the Stable Homochiral Gas-Phase Serine Octamer." Journal of Physical Chemistry B 106, no. 6 (February 2002): 1219–28. http://dx.doi.org/10.1021/jp012265l.

Full text

APA, Harvard, Vancouver, ISO, and other styles

21

Mazurek, Ulf, Orit Geller, Chava Lifshitz, Melinda A. McFarland, Alan G. Marshall, and Bryan G. Reuben. "Protonated Serine Octamer Cluster: Structure Elucidation by Gas-Phase H/D Exchange Reactions†." Journal of Physical Chemistry A 109, no. 10 (March 2005): 2107–12. http://dx.doi.org/10.1021/jp0451344.

Full text

APA, Harvard, Vancouver, ISO, and other styles

22

Sunahori, Fumie X., Guochun Yang, Elena N. Kitova, John S. Klassen, and Yunjie Xu. "Chirality recognition of the protonated serine dimer and octamer by infrared multiphoton dissociation spectroscopy." Phys. Chem. Chem. Phys. 15, no. 6 (2013): 1873–86. http://dx.doi.org/10.1039/c2cp43296j.

Full text

APA, Harvard, Vancouver, ISO, and other styles

23

Mazurek, Ulf. "Letter: Some More Aspects of Formation and Stability of the Protonated Serine Octamer Cluster." European Journal of Mass Spectrometry 12, no. 1 (February 2006): 63–69. http://dx.doi.org/10.1255/ejms.783.

Full text

APA, Harvard, Vancouver, ISO, and other styles

24

Kasibhatla, Shailaja, Pankaj Tailor, Nathalie Bonefoy-Berard, Tomas Mustelin, Amnon Altman, and Arun Fotedar. "Jun Kinase Phosphorylates and Regulates the DNA Binding Activity of an Octamer Binding Protein, T-Cell Factor β1." Molecular and Cellular Biology 19, no. 3 (March 1, 1999): 2021–31. http://dx.doi.org/10.1128/mcb.19.3.2021.

Full text

Abstract:

ABSTRACT POU domain proteins have been implicated as key regulators during development and lymphocyte activation. The POU domain protein T-cell factor β1 (TCFβ1), which binds octamer and octamer-related sequences, is a potent transactivator. In this study, we showed that TCFβ1 is phosphorylated following activation via the T-cell receptor or by stress-induced signals. Phosphorylation of TCFβ1 occurred predominantly at serine and threonine residues. Signals which upregulate Jun kinase (JNK)/stress-activated protein kinase activity also lead to association of JNK with TCFβ1. JNK associates with the activation domain of TCFβ1 and phosphorylates its DNA binding domain. The phosphorylation of recombinant TCFβ1 by recombinant JNK enhances the ability of TCFβ1 to bind to a consensus octamer motif. Consistent with this conclusion, TCFβ1 upregulates reporter gene transcription in an activation- and JNK-dependent manner. In addition, inhibition of JNK activity by catalytically inactive MEKK (in which methionine was substituted for the lysine at position 432) also inhibits the ability of TCFβ1 to drive inducible transcription from the interleukin-2 promoter. These results suggest that stress-induced signals and T-cell activation induce JNK, which then acts on multiple cissequences by modulating distinct transactivators like c-Jun and TCFβ1. This demonstrates a coupling between the JNK activation pathway and POU domain proteins and implicates TCFβ1 as a physiological target in the JNK signal transduction pathway leading to coordinated biological responses.

APA, Harvard, Vancouver, ISO, and other styles

25

Takats, Zoltan, Sergio C. Nanita, and R. Graham Cooks. "Cover Picture: Serine Octamer Reactions: Indicators of Prebiotic Relevance (Angew. Chem. Int. Ed. 30/2003)." Angewandte Chemie International Edition 42, no. 30 (August 4, 2003): 3443. http://dx.doi.org/10.1002/anie.200390541.

Full text

APA, Harvard, Vancouver, ISO, and other styles

26

Zhang, Hong, Zhenwei Wei, Jie Jiang, and R. Graham Cooks. "Nebulization Prior to Isolation, Ionization, and Dissociation of the Neutral Serine Octamer Allows Its Characterization." Angewandte Chemie 130, no. 52 (November 30, 2018): 17387–91. http://dx.doi.org/10.1002/ange.201811098.

Full text

APA, Harvard, Vancouver, ISO, and other styles

27

Zhang, Hong, Zhenwei Wei, Jie Jiang, and R. Graham Cooks. "Nebulization Prior to Isolation, Ionization, and Dissociation of the Neutral Serine Octamer Allows Its Characterization." Angewandte Chemie International Edition 57, no. 52 (November 30, 2018): 17141–45. http://dx.doi.org/10.1002/anie.201811098.

Full text

APA, Harvard, Vancouver, ISO, and other styles

28

Lansky, Shifra, Onit Alalouf, Hodaya Vered Solomon, Anat Alhassid, Lata Govada, Naomi E. Chayen, Hassan Belrhali, Yuval Shoham, and Gil Shoham. "A unique octameric structure of Axe2, an intracellular acetyl-xylooligosaccharide esterase fromGeobacillus stearothermophilus." Acta Crystallographica Section D Biological Crystallography 70, no. 2 (January 17, 2014): 261–78. http://dx.doi.org/10.1107/s139900471302840x.

Full text

Abstract:

Geobacillus stearothermophilusT6 is a thermophilic, Gram-positive soil bacterium that possesses an extensive and highly regulated hemicellulolytic system, allowing the bacterium to efficiently degrade high-molecular-weight polysaccharides such as xylan, arabinan and galactan. As part of the xylan-degradation system, the bacterium uses a number of side-chain-cleaving enzymes, one of which is Axe2, a 219-amino-acid intracellular serine acetylxylan esterase that removes acetyl side groups from xylooligosaccharides. Bioinformatic analyses suggest that Axe2 belongs to the lipase GDSL family and represents a new family of carbohydrate esterases. In the current study, the detailed three-dimensional structure of Axe2 is reported, as determined by X-ray crystallography. The structure of the selenomethionine derivative Axe2-Se was initially determined by single-wavelength anomalous diffraction techniques at 1.70 Å resolution and was used for the structure determination of wild-type Axe2 (Axe2-WT) and the catalytic mutant Axe2-S15A at 1.85 and 1.90 Å resolution, respectively. These structures demonstrate that the three-dimensional structure of the Axe2 monomer generally corresponds to the SGNH hydrolase fold, consisting of five central parallel β-sheets flanked by two layers of helices (eight α-helices and five 310-helices). The catalytic triad residues, Ser15, His194 and Asp191, are lined up along a substrate channel situated on the concave surface of the monomer. Interestingly, the Axe2 monomers are assembled as a `doughnut-shaped' homo-octamer, presenting a unique quaternary structure built of two staggered tetrameric rings. The eight active sites are organized in four closely situated pairs, which face the relatively wide internal cavity. The biological relevance of this octameric structure is supported by independent results obtained from gel-filtration, TEM and SAXS experiments. These data and their comparison to the structural data of related hydrolases are used for a more general discussion focusing on the structure–function relationships of enzymes of this category.

APA, Harvard, Vancouver, ISO, and other styles

29

Nanita, Sergio C., Zoltan Takats, R. Graham Cooks, Sunnie Myung, and David E. Clemmer. "Chiral enrichment of serine via formation, dissociation, and soft-landing of octameric cluster ions." Journal of the American Society for Mass Spectrometry 15, no. 9 (September 2004): 1360–65. http://dx.doi.org/10.1016/j.jasms.2004.06.010.

Full text

APA, Harvard, Vancouver, ISO, and other styles

30

Ren, Juan, Yi-Yun Wang, Ru-Xia Feng, and Xiang-Lei Kong. "Investigation of l / d -threonine substituted l -serine octamer ions by mass spectrometry and infrared photodissociation spectroscopy." Chinese Chemical Letters 28, no. 3 (March 2017): 537–40. http://dx.doi.org/10.1016/j.cclet.2016.10.032.

Full text

APA, Harvard, Vancouver, ISO, and other styles

31

Nebl, Gabriele, Stefan C. Meuer, and Yvonne Samstag. "Cyclosporin A-Resistant Transactivation of the IL-2 Promoter Requires Activity of Okadaic Acid-Sensitive Serine/Threonine Phosphatases." Journal of Immunology 161, no. 4 (August 15, 1998): 1803–10. http://dx.doi.org/10.4049/jimmunol.161.4.1803.

Full text

Abstract:

Abstract Expression of the IL-2 gene requires activation of T cells through stimulation of the TCR and costimulation through accessory receptors. We have found recently that okadaic acid-sensitive Ser/Thr phosphatases are involved in a cyclosporin A-insensitive pathway that selectively transmits costimulatory signals. In this study, we analyzed whether activities of these phosphatases are necessary for the expression of the IL-2 gene. In both activated peripheral blood T lymphocytes and activated tumorigenic T cell lines, IL-2 gene expression was blocked at the transcriptional level by okadaic acid. The transcription factors active at the IL-2 promoter were differentially influenced: upon down-modulation of okadaic acid-sensitive phosphatases, transactivation by octamer, NF-κB, and NF of activated T cells proteins was abrogated, while transactivation by AP-1 proteins was even enhanced.

APA, Harvard, Vancouver, ISO, and other styles

32

Gronert, Scott, Richard A. J. O'Hair, and Adelaide E. Fagin. "Ion/molecule reactions of the protonated serine octamerGas Phase Ion Chemistry of Biomolecules. Part 42.20." Chemical Communications, no. 17 (2004): 1944. http://dx.doi.org/10.1039/b407721k.

Full text

APA, Harvard, Vancouver, ISO, and other styles

33

Kim, Dong Keon, Bomin Song, Suji Han, Hansol Jang, Seung-Hyun Bae, Hee Yeon Kim, Seon-Hyeong Lee, et al. "Phosphorylation of OCT4 Serine 236 Inhibits Germ Cell Tumor Growth by Inducing Differentiation." Cancers 12, no. 9 (September 11, 2020): 2601. http://dx.doi.org/10.3390/cancers12092601.

Full text

Abstract:

Octamer-binding transcription factor 4 (Oct4) plays an important role in maintaining pluripotency in embryonic stem cells and is closely related to the malignancies of various cancers. Although posttranslational modifications of Oct4 have been widely studied, most of these have not yet been fully characterized, especially in cancer. In this study, we investigated the role of phosphorylation of serine 236 of OCT4 [OCT4 (S236)] in human germ cell tumors (GCTs). OCT4 was phosphorylated at S236 in a cell cycle-dependent manner in a patient sample and GCT cell lines. The substitution of endogenous OCT4 by a mimic of phosphorylated OCT4 with a serine-to-aspartate mutation at S236 (S236D) resulted in tumor cell differentiation, growth retardation, and inhibition of tumor sphere formation. GCT cells expressing OCT4 S236D instead of endogenous OCT4 were similar to cells with OCT4 depletion at the mRNA transcript level as well as in the phenotype. OCT4 S236D also induced tumor cell differentiation and growth retardation in mouse xenograft experiments. Inhibition of protein phosphatase 1 by chemicals or short hairpin RNAs increased phosphorylation at OCT4 (S236) and resulted in the differentiation of GCTs. These results reveal the role of OCT4 (S236) phosphorylation in GCTs and suggest a new strategy for suppressing OCT4 in cancer.

APA, Harvard, Vancouver, ISO, and other styles

34

Hornemann, Thorsten, Yu Wei, and Arnold von Eckardstein. "Is the mammalian serine palmitoyltransferase a high-molecular-mass complex?" Biochemical Journal 405, no. 1 (June 13, 2007): 157–64. http://dx.doi.org/10.1042/bj20070025.

Full text

Abstract:

SPT (serine palmitoyltransferase) catalyses the rate-limiting step for the de novo synthesis of sphingolipids. Mammalian SPT is believed to be a heterodimer composed of two subunits, SPTLC1 and SPTLC2. We reported previously the identification of a new third SPT subunit, SPTLC3. In the present study, we have investigated the structure of the SPT complex in more detail. Pull-down assays with antibodies against SPTLC3 concomitantly co-precipitated SPTLC1 and SPTLC2 in human placenta extracts and SPTLC3 overexpressing human embryonic kidney-293 cells. By size exclusion chromatography, we determined the molecular mass of the functional SPT complex to be approx. 480 kDa. By Blue-native-PAGE experiments we demonstrated that all three SPT subunits (SPTLC1–3) are co-localized within a single SPT complex. On the basis of these results we conclude that the functional SPT is not a dimer, but a higher organized complex, composed of three distinct subunits (SPTLC1, SPTLC2 and SPTLC3) with a molecular mass of 480 kDa. The stoichiometry of SPTLC2 and SPTLC3 in this complex seems not to be fixed and is probably changed dynamically in dependence of the tissue specific SPTLC2 and SPTLC3 expression levels. Based on our own and earlier published data we propose a model of an octameric SPT structure. The observed dynamic composition of the SPT complex could provide a cellular mechanism to adjust SPT activity to tissue specific requirements in sphingolipid synthesis.

APA, Harvard, Vancouver, ISO, and other styles

35

Mazurek, Ulf, Marianne Engeser, and Chava Lifshitz. "Gas-phase H/D exchange of the protonated serine octamer cluster: “Ion ping pong” of populations A and B." International Journal of Mass Spectrometry 249-250 (March 2006): 473–76. http://dx.doi.org/10.1016/j.ijms.2005.11.006.

Full text

APA, Harvard, Vancouver, ISO, and other styles

36

Hernáez, M. J., E. Andújar, J. L. Ríos, S. R. Kaschabek, W. Reineke, and E. Santero. "Identification of a Serine Hydrolase Which Cleaves the Alicyclic Ring of Tetralin." Journal of Bacteriology 182, no. 19 (October 1, 2000): 5448–53. http://dx.doi.org/10.1128/jb.182.19.5448-5453.2000.

Full text

Abstract:

ABSTRACT A gene designated thnD, which is required for biodegradation of the organic solvent tetralin by Sphingomonas macrogoltabidus strain TFA, has been identified. Sequence comparison analysis indicated that thnD codes for a carbon-carbon bond serine hydrolase showing highest similarity to hydrolases involved in biodegradation of biphenyl. An insertion mutant defective in ThnD accumulates the ring fission product which results from the extradiol cleavage of the aromatic ring of dihydroxytetralin. The gene product has been purified and characterized. ThnD is an octameric thermostable enzyme with an optimum reaction temperature at 65°C. ThnD efficiently hydrolyzes the ring fission intermediate of the tetralin pathway and also 2-hydroxy-6-oxo-6-phenylhexa-2,4-dienoic acid, the ring fission product of the biphenylmeta-cleavage pathway. However, it is not active towards the equivalent intermediates of meta-cleavage pathways of monoaromatic compounds which have small substituents in C-6. When ThnD hydrolyzes the intermediate in the tetralin pathway, it cleaves a C-C bond comprised within the alicyclic ring of tetralin instead of cleaving a linear C-C bond, as all other known hydrolases ofmeta-cleavage pathways do. The significance of this activity of ThnD for the requirement of other activities to mineralize tetralin is discussed.

APA, Harvard, Vancouver, ISO, and other styles

37

Koch, Kim J., Fabio C. Gozzo, Sergio C. Nanita, Z. Takats, Marcos N. Eberlin, and R. Graham Cooks. "Chiral Transmission between Amino Acids: Chirally Selective Amino Acid Substitution in the Serine Octamer as a Possible Step in Homochirogenesis." Angewandte Chemie International Edition 41, no. 10 (May 17, 2002): 1721–24. http://dx.doi.org/10.1002/1521-3773(20020517)41:10<1721::aid-anie1721>3.0.co;2-5.

Full text

APA, Harvard, Vancouver, ISO, and other styles

38

Koch, Kim J., Fabio C. Gozzo, Sergio C. Nanita, Z. Takats, Marcos N. Eberlin, and R. Graham Cooks. "Chiral Transmission between Amino Acids: Chirally Selective Amino Acid Substitution in the Serine Octamer as a Possible Step in Homochirogenesis." Angewandte Chemie 114, no. 10 (May 17, 2002): 1797–800. http://dx.doi.org/10.1002/1521-3757(20020517)114:10<1797::aid-ange1797>3.0.co;2-v.

Full text

APA, Harvard, Vancouver, ISO, and other styles

39

CHEN, H., M. LI, W. JIN, Q. JIN, and J. ZHENG. "Detection of Serine Octamer by Desorption Electrospray Ionization Mass Spectrometry in Resultant Mixture of Aspartic Acid Exposed to Sunshine Under Natural Conditions." Chemical Research in Chinese Universities 23, no. 6 (November 2007): 650–53. http://dx.doi.org/10.1016/s1005-9040(07)60141-x.

Full text

APA, Harvard, Vancouver, ISO, and other styles

40

Umezurike, G. M. "The octameric structure of β-glucosidase from Botryodiplodia theobromae Pat." Biochemical Journal 275, no. 3 (May 1, 1991): 721–25. http://dx.doi.org/10.1042/bj2750721.

Full text

Abstract:

1. Whereas only beta-glucosidase A (beta-D-glucoside glucohydrolase, EC 3.2.1.21) was produced by the tropical fungus Botryodiplodia theobromae Pat. (I.M.I. 115626; A.T.C.C. 26123) in young cultures containing D-cellobiose as carbon source, lower-Mr forms (B, C and D) were found in older cultures when the pH had drifted from the initial value of pH 6.2 to pH 7.9. 2. The Michaelis constants (Km) of the various molecular forms of the enzyme were 0.30 +/- 0.03 mM-, 0.26 +/- 0.01 mM-, 0.20 +/- 0.02 mM- and 0.16 +/- 0.01 mM-o-nitrophenyl beta-D-glucopyranoside for beta-glucosidase forms A (Mr 320,000), B (Mr 160,000), C (Mr 80,000) and D (Mr 40,000) respectively. 3. Only beta-glucosidase D showed substrate inhibition. 4. Only L-arginine was found as the N-terminal residue, and beta-glucosidase A contained 31.7 +/- 0.6 mol of N-terminal L-arginine/mol of the enzyme. 5. Storage of purified beta-glucosidase A under mildly alkaline conditions caused its dissociation into the lower-Mr forms, whereas adjustment of the pH of a solution of beta-glucosidase A to pH 12.0 with 1 M-NaOH led to complete inactivation on incubation at 40 degrees C for 1 h and to the release of 25.2 +/- 1.5 mol of inorganic phosphate/mol of the enzyme. 6. O-Phospho-L-serine was isolated from the acid-hydrolysis product of beta-glucosidase A but not from that of beta-glucosidase D. 7. Reduction and carboxamidomethylation of the various forms of beta-glucosidase gave only one enzymically inactive protein with an Mr of 10,000-11,000. 8. After partial succinylation (3-carboxypropionylation) of beta-glucosidase D at pH 5.0 and removal of the precipitated protein formed, the supernatant solution contained beta-glucosidase components similar to the other molecular forms (A, B and C) and an aggregate (beta-glucosidase Xs) that gave a positive result in the alkaline hydroxylamine test, whereas N-succinylated beta-glucosidase D, an aggregate (form Xp) that behaved like beta-glucosidase Xs and traces of forms A, B and C were found by gel filtration of the solution of the precipitate solubilized at neutral pH (7.0-7.7). 9. These observations are discussed in terms of the proposed octameric structure of beta-glucosidase A based on the result of electron microscopy [Umezurike (1975) Biochem. J. 145, 361-368].

APA, Harvard, Vancouver, ISO, and other styles

41

Jameson, S. C., F. R. Carbone, and M. J. Bevan. "Clone-specific T cell receptor antagonists of major histocompatibility complex class I-restricted cytotoxic T cells." Journal of Experimental Medicine 177, no. 6 (June 1, 1993): 1541–50. http://dx.doi.org/10.1084/jem.177.6.1541.

Full text

Abstract:

A previous report showed that the proliferative response of helper T cells to class II major histocompatibility complex (MHC)-restricted antigens can be inhibited by analogues of the antigen, which act as T cell receptor (TCR) antagonists. Here we define and analyze peptide variants that antagonize various functions of class I MHC-restricted cytotoxic T lymphocyte (CTL) clones. Of 64 variants at individual TCR contact sites of the Kb-restricted octamer peptide ovalbumin257-264 (OVAp), a very high proportion (40%) antagonized lysis by three OVAp-specific CTL clones. This effect was highly clone specific, since many antagonists for one T cell clone have differential effects on another. We show that this inhibition of CTL function is not a result of T cell-T cell interaction, precluding veto-like phenomena as a mechanism for antagonism. Moreover, we present evidence for direct interaction between the TCR and antagonist-MHC complexes. In further analysis of the T cell response, we found that serine esterase release and cytokine production are susceptible to TCR antagonism similarly to lysis. Ca2+ flux, an early event in signaling, is also inhibited by antagonists but may be more resistant to the antagonist effect than downstream responses.

APA, Harvard, Vancouver, ISO, and other styles

42

Ye, Peng, Xiaoxia Chi, Xiuwen Yan, Fangqin Wu, Zhigang Liang, and Wen-Hao Yang. "Alanine–Glyoxylate Aminotransferase Sustains Cancer Stemness Properties through the Upregulation of SOX2 and OCT4 in Hepatocellular Carcinoma Cells." Biomolecules 12, no. 5 (May 5, 2022): 668. http://dx.doi.org/10.3390/biom12050668.

Full text

Abstract:

Liver cancer stem cells (LCSCs) are a small subset of oncogenic cells with a self-renewal ability and drug resistance, and they promote the recurrence and metastasis of hepatocellular carcinoma (HCC). However, the mechanisms regulating LCSCs have not been fully explored. By enriching LCSCs from spheroid cultures and performing transcriptomic analysis, we determined that alanine–glyoxylate aminotransferase (AGXT), which participates in the metabolism of serine and glycine, was significantly upregulated in spheroid cultures, and its function in LCSCs remains unknown. Through the exogenous overexpression or short hairpin RNA knockdown of AGXT in HCC cells, we observed that changes in the AGXT level did not affect the spheroid ability and population of LCSCs. The knockdown of AGXT in LCSCs reduced the number of spheroids and the population of LCSCs; this implies that AGXT is required for the maintenance of cancer stemness rather than as a driver of LCSCs. Mechanistically, AGXT may sustain the self-renewal potential of LCSCs by upregulating the expression of SRY-box transcription factor 2 (SOX2) and octamer-binding transcription factor 4 (OCT4), two well-known master regulators of cancer stemness. Taken together, our study demonstrates the role of AGXT in supporting LCSCs; thus, AGXT merits further exploration.

APA, Harvard, Vancouver, ISO, and other styles

43

Noone, David, Alistair Howell, and Kevin M. Devine. "Expression of ykdA, Encoding a Bacillus subtilis Homologue of HtrA, Is Heat Shock Inducible and Negatively Autoregulated." Journal of Bacteriology 182, no. 6 (March 15, 2000): 1592–99. http://dx.doi.org/10.1128/jb.182.6.1592-1599.2000.

Full text

Abstract:

ABSTRACT There are three members of the HtrA family of serine proteases, YkdA, YvtA, and YyxA, encoded in the chromosome of Bacillus subtilis. In this study, we report on the promoter structure and regulation of ykdA expression. The ykdA gene is heat inducible, exhibiting a biphasic pattern of expression during a 60-min interval after heat shock. Increased expression after heat shock occurs at the transcriptional level. The heat-shock-inducible promoter has a single mismatch with a SigA-type −10 motif, but does not exhibit similarity to a SigA −35 region. There are six octamer repeats with a consensus TTTTCACA positioned at, and upstream of, the normal position of a −35 region. While repeats V and VI appear dispensable, repeat IV is essential for normal thermoinducible expression. This promoter structure is also found in the control region of yvtA, encoding a second member of this family of proteases. Expression of ykdA is negatively autoregulated both during the growth cycle and during heat shock. Our evidence suggests that YkdA protease activity is not required for this form of regulation. Null mutants of ykdA display increased tolerance to heat and are 80-fold more resistant to 10 mM hydrogen peroxide than wild-type cells. However, ykdA expression is not induced by hydrogen peroxide. These results indicate that the regulon to which YkdA belongs is linked to the oxidative stress response in B. subtilis.

APA, Harvard, Vancouver, ISO, and other styles

44

Trapp, Stefan, Peter Proks, Stephen J. Tucker, and Frances M. Ashcroft. "Molecular Analysis of ATP-sensitive K Channel Gating and Implications for Channel Inhibition by ATP." Journal of General Physiology 112, no. 3 (September 1, 1998): 333–49. http://dx.doi.org/10.1085/jgp.112.3.333.

Full text

Abstract:

The β cell KATP channel is an octameric complex of four pore-forming subunits (Kir6.2) and four regulatory subunits (SUR1). A truncated isoform of Kir6.2 (Kir6.2ΔC26), which expresses independently of SUR1, shows intrinsic ATP sensitivity, suggesting that this subunit is primarily responsible for mediating ATP inhibition. We show here that mutation of C166, which lies at the cytosolic end of the second transmembrane domain, to serine (C166S) increases the open probability of Kir6.2ΔC26 approximately sevenfold by reducing the time the channel spends in a long closed state. Rundown of channel activity is also decreased. Kir6.2ΔC26 containing the C166S mutation shows a markedly reduced ATP sensitivity: the Ki is reduced from 175 μM to 2.8 mM. Substitution of threonine, alanine, methionine, or phenylalanine at position C166 also reduced the channel sensitivity to ATP and simultaneously increased the open probability. Thus, ATP does not act as an open channel blocker. The inhibitory effects of tolbutamide are reduced in channels composed of SUR1 and Kir6.2 carrying the C166S mutation. Our results are consistent with the idea that C166 plays a role in the intrinsic gating of the channel, possibly by influencing a gate located at the intracellular end of the pore. Kinetic analysis suggests that the apparent decrease in ATP sensitivity, and the changes in other properties, observed when C166 is mutated is largely a consequence of the impaired transition from the open to the long closed state.

APA, Harvard, Vancouver, ISO, and other styles

45

O'Leary, Brendan, Joonho Park, and William C. Plaxton. "The remarkable diversity of plant PEPC (phosphoenolpyruvate carboxylase): recent insights into the physiological functions and post-translational controls of non-photosynthetic PEPCs." Biochemical Journal 436, no. 1 (April 27, 2011): 15–34. http://dx.doi.org/10.1042/bj20110078.

Full text

Abstract:

PEPC [PEP (phosphoenolpyruvate) carboxylase] is a tightly controlled enzyme located at the core of plant C-metabolism that catalyses the irreversible β-carboxylation of PEP to form oxaloacetate and Pi. The critical role of PEPC in assimilating atmospheric CO2 during C4 and Crassulacean acid metabolism photosynthesis has been studied extensively. PEPC also fulfils a broad spectrum of non-photosynthetic functions, particularly the anaplerotic replenishment of tricarboxylic acid cycle intermediates consumed during biosynthesis and nitrogen assimilation. An impressive array of strategies has evolved to co-ordinate in vivo PEPC activity with cellular demands for C4–C6 carboxylic acids. To achieve its diverse roles and complex regulation, PEPC belongs to a small multigene family encoding several closely related PTPCs (plant-type PEPCs), along with a distantly related BTPC (bacterial-type PEPC). PTPC genes encode ~110-kDa polypeptides containing conserved serine-phosphorylation and lysine-mono-ubiquitination sites, and typically exist as homotetrameric Class-1 PEPCs. In contrast, BTPC genes encode larger ~117-kDa polypeptides owing to a unique intrinsically disordered domain that mediates BTPC's tight interaction with co-expressed PTPC subunits. This association results in the formation of unusual ~900-kDa Class-2 PEPC hetero-octameric complexes that are desensitized to allosteric effectors. BTPC is a catalytic and regulatory subunit of Class-2 PEPC that is subject to multi-site regulatory phosphorylation in vivo. The interaction between divergent PEPC polypeptides within Class-2 PEPCs adds another layer of complexity to the evolution, physiological functions and metabolic control of this essential CO2-fixing plant enzyme. The present review summarizes exciting developments concerning the functions, post-translational controls and subcellular location of plant PTPC and BTPC isoenzymes.

APA, Harvard, Vancouver, ISO, and other styles

46

Rimm, D. L., D. A. Kaiser, D. Bhandari, P. Maupin, D. P. Kiehart, and T. D. Pollard. "Identification of functional regions on the tail of Acanthamoeba myosin-II using recombinant fusion proteins. I. High resolution epitope mapping and characterization of monoclonal antibody binding sites." Journal of Cell Biology 111, no. 6 (December 1, 1990): 2405–16. http://dx.doi.org/10.1083/jcb.111.6.2405.

Full text

Abstract:

We used a series of COOH-terminally deleted recombinant myosin molecules to map precisely the binding sites of 22 monoclonal antibodies along the tail of Acanthamoeba myosin-II. These antibodies bind to 14 distinguishable epitopes, some separated by less than 10 amino acids. The positions of the binding sites visualized by electron microscopy agree only approximately with the physical positions of these sites on the alpha-helical coiled-coil tail. On the other hand, the epitope map agrees precisely with competitive binding studies: all antibodies that share an epitope compete with each other for binding to myosin. Antibodies with adjacent epitopes can compete with each other at linear distances up to 5 or 6 nm, and many antibodies that bind 3-7-nm apart can enhance the binding of each other to myosin. Most of the antibodies that bind to the distal 37 nm of the tail disrupt assembly of octameric minifilaments and, depending upon the exact location of the binding site, stop assembly at specific steps yielding, for example, monomers, antiparallel dimers, parallel dimers or antiparallel tetramers. The effects of these antibodies on assembly identify sites on the tail that are required for individual steps in minifilament assembly. Experiments on the assembly of truncated myosin-II tails have revealed a complementary group of sites that participate in the assembly reactions (Sinard, J.H., D.L. Rimm, and T.D. Pollard. 1990. J. Cell Biol. 111:2417-2426). Antibodies that bind to the distal tail but do not affect assembly appear to have a low affinity for myosin-II. Antibodies that bind to the proximal 50 nm of the tail do not inhibit the assembly of minifilaments. Many antibodies that bind to the tail of myosin-II, even some that have no obvious effect on minifilament assembly, can inhibit the actomyosin ATPase activity and the contraction of an actin gel formed in crude extracts. An antibody that binds between amino acids 1447 and 1467 inhibits the phosphorylation of serine residues distal to residue 1483.

APA, Harvard, Vancouver, ISO, and other styles

47

Nanita, Sergio C., and R. Graham Cooks. "Serine Octamers: Cluster Formation, Reactions, and Implications for Biomolecule Homochirality." ChemInform 37, no. 20 (May 16, 2006). http://dx.doi.org/10.1002/chin.200620232.

Full text

APA, Harvard, Vancouver, ISO, and other styles

48

"Serine octamer reveals its structure." C&EN Global Enterprise 96, no. 19 (May 7, 2018): 9. http://dx.doi.org/10.1021/cen-09619-scicon6.

Full text

APA, Harvard, Vancouver, ISO, and other styles

49

Chen, Rong, Zhenwei Wei, and R. Graham Cooks. "Collection and Characterization by Mass Spectrometry of the Neutral Serine Octamer Generated upon Sublimation." Analytical Chemistry, December 10, 2020. http://dx.doi.org/10.1021/acs.analchem.0c04107.

Full text

APA, Harvard, Vancouver, ISO, and other styles

50

Jordan, Jacob S., and Evan R. Williams. "Effects of Electrospray Droplet Size on Analyte Aggregation: Evidence for Serine Octamer in Solution." Analytical Chemistry, December 28, 2020. http://dx.doi.org/10.1021/acs.analchem.0c04343.

Full text

APA, Harvard, Vancouver, ISO, and other styles

We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!