Cloning, High-Yield Expression inEscherichia coli,and Purification of Biologically Active HIV-1 Tat Protein

1996 ◽  
Vol 8 (1) ◽  
pp. 75-84 ◽  
Author(s):  
Thomas Kirsch ◽  
Markus Boehm ◽  
Oliver Schuckert ◽  
Armin U. Metzger ◽  
Dieter Willbold ◽  
...  
Keyword(s):  
Biologically Active ◽  
High Yield ◽  
Inescherichia Coli ◽  
Tat Protein ◽  
Expression Inescherichia Coli ◽  
Hiv 1

scholarly journals Optimized Supercritical CO2 Extraction Enhances the Recovery of Valuable Lipophilic Antioxidants and Other Constituents from Dual-Purpose Hop (Humulus lupulus L.) Variety Ella

Antioxidants ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 918
Author(s):  
Nóra Emilia Nagybákay ◽  
Michail Syrpas ◽  
Vaiva Vilimaitė ◽  
Laura Tamkutė ◽  
Audrius Pukalskas ◽  
...  
Keyword(s):  
Supercritical Co2 ◽  
Antioxidant Properties ◽  
Extraction Yield ◽  
Biologically Active ◽  
High Yield ◽  
Acid Extraction ◽  
Supercritical Co2 Extraction ◽  
Bioactive Constituents ◽  
Total Extract

The article presents the optimization of supercritical CO2 extraction (SFE-CO2) parameters using response surface methodology (RSM) with central composite design (CCD) in order to produce single variety hop (cv. Ella) extracts with high yield and strong in vitro antioxidant properties. Optimized SFE-CO2 (37 MPa, 43 °C, 80 min) yielded 26.3 g/100 g pellets of lipophilic fraction. This extract was rich in biologically active α- and β-bitter acids (522.8 and 345.0 mg/g extract, respectively), and exerted 1481 mg TE/g extract in vitro oxygen radical absorbance capacity (ORAC). Up to ~3-fold higher extraction yield, antioxidant recovery (389.8 mg TE/g pellets) and exhaustive bitter acid extraction (228.4 mg/g pellets) were achieved under the significantly shorter time compared to the commercially used one-stage SFE-CO2 at 10–15 MPa and 40 °C. Total carotenoid and chlorophyll content was negligible, amounting to <0.04% of the total extract mass. Fruity, herbal, spicy and woody odor of extracts could be attributed to the major identified volatiles, namely β-pinene, β-myrcene, β-humulene, α-humulene, α-selinene and methyl-4-decenoate. Rich in valuable bioactive constituents and flavor compounds, cv. Ella hop SFE-CO2 extracts could find multipurpose applications in food, pharmaceutical, nutraceutical and cosmetics industries.

HIV-1 tat protein expression in mouse brain potentiates ethanol reward and reinstates extinguished ethanol-seeking behavior

2014 ◽  
Vol 140 ◽  
pp. e141-e142
Author(s):  
Jay P. McLaughlin ◽  
M.L. Ganno ◽  
S.O. Eans ◽  
Jason J. Paris ◽  
H.D. Singh
Keyword(s):  
Protein Expression ◽  
Mouse Brain ◽  
Tat Protein ◽  
Seeking Behavior ◽  
Hiv 1

scholarly journals Identification of a novel cell attachment domain in the HIV-1 Tat protein and its 90-kDa cell surface binding protein.

1993 ◽  
Vol 268 (7) ◽  
pp. 5279-5284
Author(s):  
B.S. Weeks ◽  
K. Desai ◽  
P.M. Loewenstein ◽  
M.E. Klotman ◽  
P.E. Klotman ◽  
...  
Keyword(s):  
Cell Surface ◽  
Cell Attachment ◽  
Binding Protein ◽  
Tat Protein ◽  
Surface Binding ◽  
Cell Surface Binding ◽  
Hiv 1

scholarly journals The expression of biologically active cholera toxin inEscherichia coli

1982 ◽  
Vol 10 (16) ◽  
pp. 4883-4890 ◽  
Author(s):  
Maria L. Gennaro ◽  
Peter J. Greenaway ◽  
David A. Broadbent
Keyword(s):  
Cholera Toxin ◽  
Biologically Active ◽  
Inescherichia Coli

scholarly journals Transduction of Cu,Zn-superoxide dismutase mediated by an HIV-1 Tat protein basic domain into mammalian cells

FEBS Letters ◽  
2000 ◽  
Vol 485 (2-3) ◽  
pp. 163-167 ◽  
Author(s):  
Hyeok Yil Kwon ◽  
Won Sik Eum ◽  
Hyun Woo Jang ◽  
Jung Hoon Kang ◽  
Jiyoon Ryu ◽  
...  
Keyword(s):  
Superoxide Dismutase ◽  
Mammalian Cells ◽  
Tat Protein ◽  
Basic Domain ◽  
Hiv 1

scholarly journals The Human Immunodeficiency Virus Type 1 Tat Protein Up-Regulates the Promoter Activity of the Beta-Chemokine Monocyte Chemoattractant Protein 1 in the Human Astrocytoma Cell Line U-87 MG: Role of SP-1, AP-1, and NF-κB Consensus Sites

2000 ◽  
Vol 74 (4) ◽  
pp. 1632-1640 ◽  
Author(s):  
Siew Pheng Lim ◽  
Alfredo Garzino-Demo
Keyword(s):  
Human Immunodeficiency Virus ◽  
Promoter Activity ◽  
Tat Protein ◽  
Monocyte Chemoattractant Protein 1 ◽  
Monocyte Chemoattractant ◽  
Monocyte Chemoattractant Protein ◽  
Astrocytoma Cell ◽  
Immunodeficiency Virus ◽  
Hiv 1

ABSTRACT It has been shown that the human immunodeficiency virus type 1 (HIV-1) Tat protein can specifically enhance expression and release of monocyte chemoattractant protein 1 (MCP-1) from human astrocytes. In this study, we show evidence that Tat-induced MCP-1 expression is mediated at the transcriptional level. Transient transfection of an expression construct encoding the full-length Tat into the human glioblastoma-astrocytoma cell line U-87 MG enhances reporter gene activity from cotransfected deletion constructs of the MCP-1 promoter. HIV-1 Tat exerts its effect through a minimal construct containing 213 nucleotides upstream of the translational start site. Site-directed mutagenesis studies indicate that an SP1 site (located between nucleotides −123 and −115) is critical for both constitutive and Tat-enhanced expression of the human MCP-1 promoter, as mutation of this SP1 site significantly diminished reporter gene expression in both instances. Gel retardation experiments further demonstrate that Tat strongly enhances the binding of SP1 protein to its DNA element on the MCP-1 promoter. Moreover, we also observe an increase in the binding activities of transcriptional factors AP1 and NF-κB to the MCP-1 promoter following Tat treatment. Mutagenesis studies show that an upstream AP1 site and an adjacent NF-κB site (located at −128 to −122 and −150 to −137, respectively) play a role in Tat-mediated transactivation. In contrast, a further upstream AP1 site (−156 to −150) does not appear to be crucial for promoter activity. We postulate that a Tat-mediated increase in SP1 binding activities augments the binding of AP1 and NF-κB, leading to synergistic activation of the MCP-1 promoter.

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