scholarly journals Antimycobacterial and HIV-1 Reverse Transcriptase Activity of Julianaceae and Clusiaceae Plant Species from Mexico

2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Rocio Gómez-Cansino ◽  
Clara Inés Espitia-Pinzón ◽  
María Guadalupe Campos-Lara ◽  
Silvia Laura Guzmán-Gutiérrez ◽  
Erika Segura-Salinas ◽  
...  
Keyword(s):  
Reverse Transcriptase ◽  
Antimycobacterial Activity ◽  
Reverse Transcriptase Activity ◽  
Hiv Reverse Transcriptase ◽  
Leaf Extracts ◽  
Calophyllum Brasiliense ◽  
Hplc Profiles ◽  
Low Toxicity ◽  
Hiv Rt

The extracts of 14 Julianaceae and 5 Clusiaceae species growing in Mexico were testedin vitro(50 µg/mL) againstMycobacterium tuberculosisH37Rv and HIV reverse transcriptase (HIV-RT). The Julianaceae bark and leaf extracts inhibitedM. tuberculosis(>84.67%) and HIV-RT (<49.89%). The Clusiaceae leaves extracts also inhibited both targets (>58.3% and >67.6%), respectively. The IC50values for six selected extracts and their cytotoxicity (50 µg/mL) to human macrophages were then determined.Amphipterygium glaucum,A. molle, andA. simplicifoliumfairly inhibitedM. tuberculosiswith IC50of 1.87–2.35 µg/mL; but their IC50against HIV-RT was 59.25–97.83 µg/mL.Calophyllum brasiliense,Vismia baccifera, andVismia mexicanaeffect onM. tuberculosiswas noteworthy (IC503.02–3.64 µg/mL) and also inhibited RT-HIV (IC5026.24–35.17 µg/mL). These 6 extracts (50 µg/mL) presented low toxicity to macrophages (<23.8%). The HPLC profiles ofA. glaucum,A. molle, andA. simplicifoliumindicated that their antimycobacterial activity cannot be related to masticadienonic, 3α, or 3β-hydromasticadienonic acids, suggesting that other compounds may be responsible for the observed activity or this might be a synergy result. The anti-HIV-RT and antimycobacterial activities induced byC. brasiliensecan be attributed to the content of calanolides A, B, as well as soulatrolide.

In Vitro HIV Type-1 Reverse Transcriptase Inhibitory Activity from Leaf Extracts ofScoparia dulcisL.

2009 ◽  
Vol 15 (3) ◽  
pp. 241-247 ◽  
Author(s):  
Mahendar Porika ◽  
Mahender Aileni ◽  
Venugopal Rao Kokkirala ◽  
Kranthi Gadidasu ◽  
Pavan Umate ◽  
...  
Keyword(s):  
Reverse Transcriptase ◽  
Inhibitory Activity ◽  
Leaf Extracts ◽  
Hiv Type 1

scholarly journals Inhibition of HIV-reverse transcriptase activity by some phloroglucinol derivatives

FEBS Letters ◽  
1991 ◽  
Vol 286 (1-2) ◽  
pp. 83-85 ◽  
Author(s):  
Hideo Nakane ◽  
Munehisa Arisawa ◽  
Akio Fujita ◽  
Saburo Koshimura ◽  
Katsuhiko Ono
Keyword(s):  
Reverse Transcriptase ◽  
Reverse Transcriptase Activity ◽  
Hiv Reverse Transcriptase ◽  
Transcriptase Activity ◽  
Phloroglucinol Derivatives

scholarly journals 3′-Azido-3′-deoxythymidine drug resistance mutations in HIV-1 reverse transcriptase can induce long range conformational changes

1998 ◽  
Vol 95 (16) ◽  
pp. 9518-9523 ◽  
Author(s):  
Jingshan Ren ◽  
Robert M. Esnouf ◽  
Andrew L. Hopkins ◽  
E. Yvonne Jones ◽  
Ian Kirby ◽  
...  
Keyword(s):  
Drug Resistance ◽  
Reverse Transcriptase ◽  
Long Range ◽  
Conformational Changes ◽  
Active Site ◽  
Common Mechanism ◽  
Resistance Mutations ◽  
Hiv Reverse Transcriptase ◽  
Drug Resistance Mutations ◽  
Hiv Rt

HIV reverse transcriptase (RT) is one of the main targets for the action of anti-AIDS drugs. Many of these drugs [e.g., 3′-azido-3′-deoxythymidine (AZT) and 2′,3′-dideoxyinosine (ddI)] are analogues of the nucleoside substrates used by the HIV RT. One of the main problems in anti-HIV therapy is the selection of a mutant virus with reduced drug sensitivity. Drug resistance in HIV is generated for nucleoside analogue inhibitors by mutations in HIV RT. However, most of these mutations are situated some distance from the polymerase active site, giving rise to questions concerning the mechanism of resistance. To understand the possible structural bases for this, the crystal structures of AZT- and ddI-resistant RTs have been determined. For the ddI-resistant RT with a mutation at residue 74, no significant conformational changes were observed for the p66 subunit. In contrast, for the AZT-resistant RT (RTMC) bearing four mutations, two of these (at 215 and 219) give rise to a conformational change that propagates to the active site aspartate residues. Thus, these drug resistance mutations produce an effect at the RT polymerase site mediated simply by the protein. It is likely that such long-range effects could represent a common mechanism for generating drug resistance in other systems.

scholarly journals Reverse Transcriptase Activity in Mature Spermatozoa of Mouse

2000 ◽  
Vol 148 (6) ◽  
pp. 1107-1114 ◽  
Author(s):  
Roberto Giordano ◽  
Anna Rosa Magnano ◽  
Germana Zaccagnini ◽  
Carmine Pittoggi ◽  
Nicola Moscufo ◽  
...  
Keyword(s):  
Reverse Transcriptase ◽  
Pcr Amplification ◽  
Reverse Transcriptase Activity ◽  
Pcr Analysis ◽  
Immunogold Electron Microscopy ◽  
Direct Pcr ◽  
Vitro Fertilization ◽  
Rna Molecules ◽  
Exogenous Rna

We show here that a reverse transcriptase (RT) activity is present in murine epididymal spermatozoa. Sperm cells incubated with human poliovirus RNA can take up exogenous RNA molecules and internalize them in nuclei. Direct PCR amplification of DNA extracted from RNA-incubated spermatozoa indicate that poliovirus RNA is reverse-transcribed in cDNA fragments. PCR analysis of two-cell embryos shows that poliovirus RNA-challenged spermatozoa transfer retrotranscribed cDNA molecules into eggs during in vitro fertilization. Finally, RT molecules can be visualized on sperm nuclear scaffolds by immunogold electron microscopy. These results, therefore, reveal a novel metabolic function in spermatozoa, which may play a role during early embryonic development.

Functional organization of the retrotransposon Ty from Saccharomyces cerevisiae: Ty protease is required for transposition

1988 ◽  
Vol 8 (4) ◽  
pp. 1421-1431 ◽  
Author(s):  
S D Youngren ◽  
J D Boeke ◽  
N J Sanders ◽  
D J Garfinkel
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Reverse Transcriptase ◽  
Functional Organization ◽  
Core Protein ◽  
Reverse Transcriptase Activity ◽  
Protein Domain ◽  
Particle Assembly ◽  
Low Levels ◽  
Viruslike Particles

We used several mutations generated in vitro to further characterize the functions of the products encoded by the TyB gene of the transpositionally active retrotransposon TyH3 from Saccharomyces cerevisiae. Mutations close to a core protein domain of TyB, which is homologous to retroviral proteases, have striking effects on Ty protein processing, the physiology of Ty viruslike particles, and transposition. The Ty protease is required for processing of both TyA and TyB proteins. Mutations in the protease resulted in the synthesis of morphologically and functionally aberrant Ty viruslike particles. The mutant particles displayed reverse transcriptase activity, but did not synthesize Ty DNA in vitro. Ty RNA was present in the mutant particles, but at very low levels. Transposition of a genetically tagged element ceased when the protease domain was mutated, demonstrating that Ty protease is essential for transposition. One of these mutations also defined a segment of TyB encoding an active reverse transcriptase. These results indicate that the Ty protease, like its retroviral counterpart, plays an important role in particle assembly, replication, and transposition of these elements.

scholarly journals CHEMICAL CHARACTERIZATION AND EVALUATION OF ANTIBACTERIAL, ANTIFUNGAL, ANTIMYCOBACTERIAL, AND CYTOTOXIC ACTIVITIES OF Talinum paniculatum

2015 ◽  
Vol 57 (5) ◽  
pp. 397-405 ◽  
Author(s):  
Luis F.C. DOS REIS ◽  
Cláudio D. CERDEIRA ◽  
Bruno F. DE PAULA ◽  
Jeferson J. da SILVA ◽  
Luiz F.L. COELHO ◽  
...  
Keyword(s):  
Micrococcus Luteus ◽  
Folk Medicine ◽  
Chemical Characterization ◽  
Antimycobacterial Activity ◽  
Cytotoxic Activities ◽  
Microdilution Method ◽  
Broth Microdilution Method ◽  
Low Toxicity ◽  
Diffusion Assay

SUMMARY In this study, the bioactivity of Talinum paniculatum was evaluated, a plant widely used in folk medicine. The extract from the T. paniculatum leaves (LE) was obtained by percolation with ethanol-water and then subjecting it to liquid-liquid partitions, yielding hexane (HX), ethyl acetate (EtOAc), butanol (BuOH), and aqueous (Aq) fractions. Screening for antimicrobial activity of the LE and its fractions was evaluated in vitro through broth microdilution method, against thirteen pathogenic and non-pathogenic microorganisms, and the antimycobacterial activity was performed through agar diffusion assay. The cytotoxic concentrations (CC90) for LE, HX, and EtOAc were obtained on BHK-21 cells by using MTT reduction assay. The LE showed activity against Serratia marcescens and Staphylococcus aureus, with Minimum Inhibitory Concentration (MIC) values of 250 and 500 µg/mL, respectively. Furthermore, HX demonstrated outstanding activity against Micrococcus luteus and Candida albicans with a MIC of 31.2 µg/mL in both cases. The MIC for EtOAc also was 31.2 µg/mL against Escherichia coli. Conversely, BuOH and Aq were inactive against all tested microorganisms and LE proved inactive against Mycobacterium tuberculosisand Mycobacterium bovisas well. Campesterol, stigmasterol, and sitosterol were the proposed structures as main compounds present in the EF and HX/EtOAc fractions, evidenced by mass spectrometry. Therefore, LE, HX, and EtOAc from T. paniculatumshowed potential as possible sources of antimicrobial compounds, mainly HX, for presenting low toxicity on BHK-21 cells with excellent Selectivity Index (SI = CC90/MIC) of 17.72 against C. albicans.

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