Journal of Pharmacy And Bioallied Sciences
Journal of Pharmacy And Bioallied Sciences Login  | Users Online: 18  Print this pageEmail this pageSmall font sizeDefault font sizeIncrease font size 
    Home | About us | Editorial board | Search | Ahead of print | Current Issue | Past Issues | Instructions | Online submission




 
 Table of Contents  
ORIGINAL ARTICLE
Year : 2012  |  Volume : 4  |  Issue : 1  |  Page : 66-69  

Antiplasmodial activity of bacilosarcin A isolated from the octocoral-associated bacterium Bacillus sp. collected in Panama


1 Center for Drug Discovery, Institute for Scientific Research and Technology Services (INDICASAT), Clayton, City of Knowledge, Republic of Panama
2 Center for Cellular and Molecular Biology of Diseases, Institute for Scientific Research and Technology Services (INDICASAT), Clayton, City of Knowledge, Republic of Panama
3 Smithsonian Tropical Research Institute Balboa, Ancon, Republic of Panama

Date of Submission01-Aug-2011
Date of Decision12-Sep-2011
Date of Acceptance14-Sep-2011
Date of Web Publication9-Feb-2012

Correspondence Address:
Marcelino Gutierrez
Center for Drug Discovery, Institute for Scientific Research and Technology Services (INDICASAT), Clayton, City of Knowledge
Republic of Panama
Login to access the Email id

Source of Support: Partially supported by the National Secretariat for Science and Technology of Panama (SENACYT, grant number COL08-061) and the Fogarty International Centerís International Cooperative Biodiversity Groups program (grant number TW006634), Conflict of Interest: None


DOI: 10.4103/0975-7406.92739

Rights and Permissions
   Abstract 

Aim: This study was designed for isolating and characterizing antiplasmodial compounds from marine octocoral-associated bacteria. Materials and Methods: The organic extract of the Bacillus sp. was subjected to purification using several chromatography techniques guided by bioassays to yield three isocoumarin derivatives (1-3). Chemical structures of the compounds were elucidated on the basis of HRMS spectra and NMR spectroscopy. The antiplasmodial activity of the isolated compounds was evaluated in vitro against the chloroquine-resistant Plasmodium falciparum strain W2. Results: Isolated compounds were identified as bacilosarcin A (1), AI77-F (2), and AI77-H (3). Bacilosarcin A (1) displayed a low micromolar activity (IC 50 = 2.2 μM) against P. falciparum while compounds 2 and 3 showed no activity. Conclusions: Bacilosarcin A was found to be responsible for the antiplasmodial activity observed in the crude extract obtained from the Bacillus sp.

Keywords: Bacillus , bacilosarcin A, isocoumarins, Leptogorgia alba, marine bacteria, octocorals, Plasmodium falciparum


How to cite this article:
Boya CA, Herrera L, Guzman HM, Gutierrez M. Antiplasmodial activity of bacilosarcin A isolated from the octocoral-associated bacterium Bacillus sp. collected in Panama. J Pharm Bioall Sci 2012;4:66-9

How to cite this URL:
Boya CA, Herrera L, Guzman HM, Gutierrez M. Antiplasmodial activity of bacilosarcin A isolated from the octocoral-associated bacterium Bacillus sp. collected in Panama. J Pharm Bioall Sci [serial online] 2012 [cited 2016 Aug 30];4:66-9. Available from: http://www.jpbsonline.org/text.asp?2012/4/1/66/92739

Malaria continues to be an uncontrolled disease that affects 106 countries in tropical regions, and half of the world's population is at risk of infection. According to the 2010 World Malaria Report of the World Health Organization (WHO), in 2009 there were 225 million cases of malaria and approximately 781,000 deaths. [1]

Efforts to develop an effective vaccine to prevent malaria have not been successful, despite the fact that several vaccine candidates have reached phase I-II, and even phase III clinical trials. [2],[3] Additionally, the development of drug resistance by malaria parasites creates a more complex scenario for the treatment of this disease. [4],[5] Given this situation, there is an urgent need for finding new antimalarial compounds with new mechanisms of action.

Natural products have played an important role in the discovery of novel compounds for the treatment of malaria. Several plant metabolites, such as quinine and artemisinin, have been the classical drugs used to treat this disease. These plant-derived compounds have also inspired synthetic drugs with improved antimalarial properties, such as chloroquine and artemeter. Unfortunately, Plasmodiun falciparum has developed resistance to all current drugs used for the treatment of malaria, except for artemisinin derivatives (ACTs). [3,[4],[5] However, a decrease in the in vivo susceptibility of P. falciparum to ACT treatment has been observed. [6]

Although terrestrial plants have been the traditional source of antimalarial drugs; the oceans have also proven to be a rich source of antimalarials, with over 60 antiplasmodial compounds isolated from marine organisms prior to 2010. [7],[8] Among marine organisms, bacteria are emerging as an important resource for drug discovery due to their outstanding capacity to biosynthesize active molecules. [9],[10] Marine cyanobacteria, [7],[8] and sediment-associated actinomycetes [11] represent promising new sources of antimalarial compounds, even though their biosynthetic capacity has been used primarily in oncology. [10]

As a part of our drug discovery program on marine organisms, we are exploring the diversity of bacteria associated with Panamanian marine invertebrates as sources for new bioactive compounds. With this goal, crude extracts and fractions from marine bacteria were screened in a panel of assays against cancer and neglected tropical diseases including malaria, Chagas' disease, and leishmaniasis. Herein we report the antiplasmodial activity of bacilosarcin A (1), an isocoumarin derivative isolated from the extract of the bacterium Bacillus sp. associated with the octocoral Leptogorgia alba.


   Materials and Methods Top


Optical rotations were measured with a Jasco P-2000 polarimeter. NMR spectra were acquired on Jeol Eclipse 400 MHz and Bruker Avance 600 MHz spectrometers and referenced to residual solvent 1 H and 13 C signals (δH 7.26, δC 77.0 for CDCl 3 ; and δH 2.50, δC 39.5 for DMSO-d6 ). Low-resolution ESIMS spectra were acquired on Jeol LC-mate mass spectrometer, while high-accuracy mass measurements were obtained on Agilent 6230 mass spectrometer. The purification of the compounds was carried out on Agilent 1200 HPLC system equipped with a quaternary pump, a diode array detector, and a normal phase silica gel column (Phenomenex Sphereclone, 4.6 mm × 100 mm, 5 μm) at a flow rate of 1 mL/min.

Biological material collection and identification

The octocoral L. alba was hand collected using SCUBA at 10 m near Otoque Island, located on the Pacific Ocean side off the coast of Panama in August 2009. A piece of the coral was rinsed with autoclaved seawater to remove loosely attached bacteria, and a small portion (0.5 mL) of the coral mucus was inoculated directly on agar plates with the seawater-based nutrient medium (8 g of Noble agar, 500 mg of mannitol, 100 mg of peptone, rifampicin [5 μg/mL] in 1 L of natural sea water). Agar plates were taken to the laboratory and observed for bacterial isolation, at room temperature over a period of 1 month. Strain GL0033 was further isolated from the collection plate and successively replated until a pure strain was obtained.

The coral specimen was identified as L. alba based on its morphology and SEM micrographs of the coral sclerites following Breedy and Guzman. [12] The taxonomic identification of bacterial strain GL0033 was carried out using PCR amplification and 16 S rRNA gene sequencing. The NCBI BLAST search for the GL0033 sequence indicated that this strain was 100% similar to Bacillus sp. Reference specimens of the coral (GLOT-120209-02) and the bacterial strain (GL0033) are deposited at INDICASAT's CEDD.

Fermentation and extraction

Bacterium GL0033 was inoculated in six 2 L Erlenmeyer flasks, each containing 1 L of the culture broth (4 g of peptone, 2 g of the yeast extract, and 2 mL of glycerol in 1 L of natural seawater). Twenty grams of sterile Amberlite® XAD-16 resin was added to each Erlenmeyer flask with the culture medium. After 10 days of cultivation at room temperature (20°C) at 172 rpm, the resin was filtered, washed with deionized water, and eluted with methanol. The culture medium (6 L) was extracted with EtOAc (3 × 6 L). The organic extracts were combined and the solvents were removed under reduced pressure to yield 3.4 g of the crude extract.

Isolation of compounds

The crude extract (3.0 g) was fractionated using reverse phase C-18 solid phase extraction (SPE) cartridges, eluted with a step gradient of 20%, 40%, 60%, 80%, and 100% MeOH in water. The MeOH/water 60:40 SPE fraction showed 84% growth inhibition of the P. falciparum. The fraction was then subjected to HPLC purification on a normal phase silica gel column (Phenomenex Sphereclone, 250 × 4.5 mm, 1 mL/min) using the isocratic elution of 7:3 EtOAc/hexanes, over 70 mins to yield 0.8 mg of bacilosarcin A (1), 0.7 mg of AI77-F (2), and 0.8 mg of AI77-H (3).

Bacilosarcin A (1): White amorphous powder, [α] 25 D 24.5 (c 0.5, CHCl 3 ); 1 H NMR (400 MHz, CDCl 3 ) δ 10.68 (1H, bs, OH), 7.42 (1H, dd, J = 8.2, 7.5 Hz, H-6), 6.94 (1H, d, J = 9.9 Hz, H-6'), 6.89 (1H, d, J = 8.2 Hz, H-7), 6.70 (1H, d, J = 7.5 Hz, H-5), 6.41 (1H, bs, NH), 4.59 (1H, dt, J = 13.1, 2.7 Hz, H-3), 4.39 (1H, m, H-5'), 4.09 (1H, dd, J = 9.9, 2.6 Hz, H-9'), 3.93 (1H, d, J = 9.9 Hz, H-8'), 3.50 (1H, dd, J = 7.0, 2.6 Hz, H-10'), 3.08 (1H, dd, J = 16.1, 13.1 Hz, H-4a), 2.84 (1H, dd, J = 16.1, 2.7 Hz, H-4b), 2.63 (1H, d, J = 17.9 Hz, H-11'a), 2.46 (1H, dd, J = 17.9, 7.0 Hz, H-11'b), 1.76 (1H, ddd, J = 13.8, 9.9, 4.9 Hz, H-4'a), 1.66 (1H, m, H-3'), 1.44 (ddd, J = 13.8, 9.1, 4.8 Hz, H-4'b), 1.34 (3H, s, H-13'), 1.30 (3H, s, H-16'), 0.97(3H, d, J = 6.4 Hz, H-2'), 0.95 (3H, d, J = 6.3 Hz, H-1'); 13 C NMR (100 MHz, CDCl 3 ) δ ppm 172.3 (C, C-7'), 171.3 (C, C-12'), 169.7 (C, C-1), 162.1 (C, C-8), 139.3 (C,C-10), 136.6 (CH, C-6), 118.2 (CH, C-5), 116.3 (CH, C-7), 108.1 (C, C-9), 98.0 (C, C-15'), 81.2 (CH, C-3), 72.5 (CH, C-9'), 69.7, (C, C-14'), 68.2 (CH, C-8'), 49.6 (CH, C-5'), 47.9 (CH,C-10'), 41.0 (CH 2 , C-4'), 30.5 (CH 2 , C-4), 30.3 (CH 2 , C-11'), 24.7 (CH, C-3'), 23.8 (CH 3 , C-16'), 23.1 (CH 3 , C-2'), 21.8 (CH 3 , C-1'), 21.3 (CH 3 , C-13'); HRESITOF-MS m/z 492.2338 [M + H] + (calculated for C 24 H 34 N 3 O 8 , 492.2340).

AI77-F (2): White amorphous powder, [α] 25 D - 106.4 (c 0.2, CHCl 3 ); 1 H NMR (400 MHz, DMSO-d6) δ ppm 10.81 (1H, s, C8-OH), 7.83 (1H, d, J = 10.0, H-6'), 7.52 (1H, dd, J = 5.7, 1.1, H-10'), 7.50 (1H, t, J = 8.0 Hz, H-6), 6.86 (1H, d, J = 8.0, H-7), 6.84 (1H, d, J = 6.1 Hz, H-5), 6.28 (1H, dd, J = 5.7, 2.0, H-11'), 6.21 (1H, d, J = 6.0, C8'-OH), 5.36 (1H, dt, J = 3.8, 1.1, H-9'), 4.69 (1H, ddd, J = 8.9, 6.0, 4.2, H-3), 4.41 (1H, dd, J = 6.6, 3.8, H-8'), 4.17 (1H, ddd, J = 13.5, 10.0, 4.2, H-5'), 2.97 (2H, m, H-4), 1.69 (1H, m, H-4'-a), 1.58 (1H, m, H-3'), 1.31 (1H, ddd, J = 13.5, 10.0, 3.8, H-4'-b), 0.91 (3H, d, 6.6, H-2'), 0.84 (3H, d, 6.4, H-1'); 13 C NMR (100 MHz, DMSO-d6) δ ppm 172.7 (C, C-12'), 169.7 (C, C-1), 168.8 (C, C-7'), 160.81 (C, C-8), 154.5 (CH, C-10'), 140.2 (C, C-10), 136.3 (CH, C-6), 121.7 (CH, C-11'), 118.5 (CH, C-5), 115.3 (CH, C-7), 108.4 (C, C-9), 84.1 (CH, C-9'), 80.8 (CH, C-3), 70.6 (CH, C-8'), 48.3 (CH, C-5'), 38.8 (CH 2 , C-4'), 29.1 (CH 2 , C-4), 24.05 (CH, C-3'), 23.3(CH 3 , C2'), 21.3 (CH 3 , C-1'); HRESIFT-MS [M + Na]+ m/z 412.1365 (calculated for C 20 H 23 NO 7 Na, 412.1367).

AI77-H (3): White amorphous powder, [α] 25 D - 33 (c 0.2, CHCl 3 ); 1 H NMR (600 MHz, CDCl 3 ) δ ppm 10.76 (1H, s, C8-OH), 7.66 (1H, d, J = 5.1 Hz, H-10'), 7.41 (1H, t, J = 7.9 Hz, H-6), 6.88 (1H, m, H-7), 6.87 (1H, m, H-6'), 6.69 (d, J = 7.9 Hz, H-5), 6.19 (1H, d, J = 5.1 Hz, H-11'), 5.30 (1H, d, J = 5.1 Hz, H-9'), 4.60 (1H, d, J = 13.6 Hz, H-3), 4.37 (1H, m, H-5'), 4.30 (1H, d, J = 5.2 Hz, H-8'), 3.02 (1H, dd, J = 16.1, 13.6 Hz, H-4a), 2.84 (1H, dd, J = 16.1, 2.6 Hz, H-4b), 1.83 (1H, m, H-4'a), 1.69 (1H, m, H-3'), 1.47 (1H, ddd, J = 13.8, 9.2, 4.6 Hz, H-4'b), 0.97 (3H, d, J = 6.6 Hz, H-2'), 0.95 (3H, d, J = 6.1 Hz, H-1'); 13 C NMR (100 MHz, CDCl 3 ) δ ppm 171.9 (C, C-12'), 169.4 (C, C-1), 168.9 (C, C-7'), 162.2 (C, C-8), 153.4 (CH, C-10'), 139.1 (C, C-10), 136.5 (CH, C-6), 122.9 (CH, C-11'), 118.2 (CH, C-5), 116.3 (CH, C-7), 108.0 (C, C-9), 83.3 (CH, C-9'), 80.8 (CH, C-3), 72.0 (CH,C-8'), 49.4 (CH,C-5'), 40.5 (CH 2 , C-4'), 30.3 (CH 2 , C-4), 24.7 (CH, C-3'), 23.0 (CH 3 ,C-2'), 21.8 (CH 3 ,C-1'); HRESIMS [M + Na]+ m/z 412.1369 (calculated for C 20 H23 NO7 Na, 412.1367).

Biological activity

The antiplasmodial activity was determined in a chloroquine-resistant P. falciparum strain (W2) utilizing a microfluorimetric assay to measure the inhibition of the parasite growth based on the detection of the parasitic DNA by intercalation with PicoGreen. [13] P. falciparum was cultured according to the methods described by Trager and Jensen. [14] The parasites were maintained in a 2% hematocrit on flat-bottomed flasks (75 mL) with the RPMI 1640 medium (Gibco-BRL) supplemented with 10% human serum.

Cytotoxicity was measured in MCF-7 human breast cancer cells with the cell viability being determined by MTT reduction. [15] Cells were seeded in 96-well plates at a rate of 6000 cells/well in 180 μL of the medium. After 24 h, the test chemicals were dissolved in DMSO and diluted in the medium without fetal bovine serum and then added to the plate at a rate of 20 μg/well. DMSO was less than 0.5% of the final concentration. After 48 h, the medium was removed and cell viability determined.


   Results and Discussion Top


The bacterial strain GL0033 was isolated from the octocoral L. alba collected near Otoque Island, Gulf of Panama, Pacific Panama. The bacterium was identified as Bacillus sp. based on its 16S rRNA sequence.

The organic crude extract of strain GL0033 obtained from the culture broth showed a strong inhibition on the growing of chloroquine-resistant Plasmodium falciparum. The bioassay-guided fractionation of the extract using SPE fractionation followed by HPLC purification yielded compounds 1-3 [Figure 1]. Structures of 1-3 were identified as bacilosarcin A (1), [16],[17] AI77-F (2), [18] and AI77-H (3), [19] on the basis of their spectroscopic data ( 1 H-NMR, 13 C-NMR, HRESITOF-MS, and optical rotations) and their comparison with spectroscopic data from the literature.
Figure 1: Structures of compounds 1-3 isolated from Bacillus sp

Click here to view


Compounds 1-3 where evaluated for their activity against chloroquine-resistant P. falciparum [Table 1]. Bacilosarcin A (1) showed an IC50 value of 2.2 μM in the antiplasmodial assay, whereas compounds 1-2 did not show any activity [Table 1].
Table 1: Biological activity of compounds 1-3 against Plasmodium falciparum and MCF-7 breast cancer cell lines

Click here to view


Compounds 1-3 possess the same 3,4-dihydro-8-hydroxy-isocoumarin moiety; however, bacilosarcin A (1) includes a 3-oxa-6,9-diazabicyclo[3.3.1]nonane ring system attached to carbon C-8', instead of the α-β-unsaturated butenolide ring present in compounds 2 and 3. From these structural features, we can infer that the heterobicyclic ring system attached to C-8' in bacilosarcin A is required for its antimalarial activity. Compounds 1-3 were also evaluated for their cytotoxicity using MCF-7 human breast cancer cell lines and showed no significant cytotoxic effect in this assay [Table 1].

One of the more remarkable structural features of bacilosarcin A (1) is its unprecedented 3-oxa-6,9-diazabicyclo[3.3.1]nonane ring system which brought the attention of synthetic organic chemists resulting in the total synthesis of compound 1. [17]

This is the first report of the antiplasmodial activity of bacilosarcin A (1), which constitutes a new addition to the few existing antiplasmodial metabolites isolated from heterotrophic bacteria associated with corals. This finding confirms that bacteria associated with marine invertebrates represent a promising resource for antimalarial research.


   Acknowledgments Top


We gratefully acknowledge the Government of Panama (ANAM, ARAP) for granting permission to make these collections; to J. Ballesteros, J. Sánchez, and Dr. J. Martínez for the taxonomic identification of the bacterium; and to Dr. C. Spadafora for the malaria and cytotoxicity assays. This work was partially supported by the National Secretariat for Science and Technology of Panama (SENACYT, grant number COL08-061) and the Fogarty International Center's International Cooperative Biodiversity Groups program (grant number TW006634).

 
   References Top

1.World Health Organization [http://www.who.int] World Malaria Report 2010. Available from: http://www.who.int/malaria/publications/atoz/9789241564106/en/index.html [Last accessed on 2011 July 17].  Back to cited text no. 1
    
2.Chilengi R. Clinical development of malaria vaccines: Should earlier trials be done in malaria endemic countries? Hum Vaccin 2009;5:627-36.  Back to cited text no. 2
[PUBMED]  [FULLTEXT]  
3.Sauerwein RW, Roestenberg M, Moorthy VS. Experimental human challenge infections can accelerate clinical malaria vaccine development. Nature Rev Immunol 2001;11:57-64.  Back to cited text no. 3
    
4.Escalante AA, Smith DL, Kim Y. The dynamics of mutations associated with anti-malarial drug resistance in Plasmodium falciparum. Trends Parasitol 2009;25:557-63.  Back to cited text no. 4
[PUBMED]  [FULLTEXT]  
5.Cravo P, Culleton R, Afonso A, Ferreira ID, Rosario VE. Mechanisms of drug resistance in malaria: Current and new challenges. Antiinfect Agents Med Chem 2006;5:63-73.  Back to cited text no. 5
    
6.Rodriguez LA, Henriques G, Borges ST, Hunt P, Sanchez CP, Martinelli A, et al. Experimental evolution of resistance to artemisinin combination therapy results in amplification of the mdr1 gene in a rodent malaria parasite. Plos One 2010;5:e11593.  Back to cited text no. 6
    
7.Fattorusso E, Taglialatela-Scafati O. Marine antimalarials. Mar Drugs 2009;7:130-52.  Back to cited text no. 7
[PUBMED]  [FULLTEXT]  
8.Peach KC, Linington RG. New innovations for an old infection: Antimalarial lead discovery from marine natural products during the period 2003-2008. Future Med Chem 2009;1:593-617.  Back to cited text no. 8
[PUBMED]    
9.Gulder TA, Moore BS. Chasing the treasures of the sea-bacterial marine natural products. Curr Opin Microbiol 2009;12:252-60.  Back to cited text no. 9
[PUBMED]  [FULLTEXT]  
10.Williams PG. Panning for chemical gold: Marine bacteria as a source of new therapeutics. Trends Biotechnol 2008;27:45-52.  Back to cited text no. 10
[PUBMED]  [FULLTEXT]  
11.Prudhomme J, McDaniel E, Ponts N, Bertani S, Fenical W, Jensen P, et al. Marine actinomycetes: A new source of compounds against the human malaria parasite. Plos One 2008;3:e2335.  Back to cited text no. 11
[PUBMED]  [FULLTEXT]  
12.Breedy O, Guzman HM. A revision of the genus Leptogorgia Milne Edwards and Haime, 1857 (Coelenterata: Octocorallia: Gorgoniidae) in the eastern Pacific. Zootaxa 2007;1419:1-90.  Back to cited text no. 12
    
13.Corbett Y, Herrera L, Gonzalez J, Cubilla L, Capson TL, Colley PD. et al. A novel DNA-based microfluorimetric method to evaluate antimalarial drug activity. Am J Trop Med Hyg 2004;70:119-24.  Back to cited text no. 13
    
14.Trager W, Jensen JB. Human malaria parasites in continuous culture. Science 1976;193:673-5.  Back to cited text no. 14
[PUBMED]  [FULLTEXT]  
15.Manger RL, Leja LS, Lee SY, Hungerford JM, Hokama Y, Dickey RW, et al. Detection of sodium channel toxins: Directed cytotoxicity assays of purified ciguatoxins, brevetoxins, saxitoxins, and seafood extracts. J AOAC Int 1995;78:521-7.  Back to cited text no. 15
[PUBMED]    
16.Azumi M, Ogawa K, Fujita T, Takeshita M. Yoshida R, Furumai T, et al. Bacilosarcins A and B, novel bioactive isocoumarins with unusual heterocyclic cores from the marine-derived bacterium Bacillus subtilis.Tetrahedron 2008;64:6420-5.  Back to cited text no. 16
    
17.Enomoto M, Kuwahara S. Total synthesis of bacilosarcins A and B. Angew Chem Int Ed Engl 2009;48:1144-8.  Back to cited text no. 17
[PUBMED]  [FULLTEXT]  
18.Shimojima Y, Hayashi H, Ooka T, Shibukawa M, Iitaka Y. Studies on AI-77s, microbial products with gastroprotective activity. Structures and the chemical nature of AI-77s. Tetrahedron 1984;40:2519-27.  Back to cited text no. 18
    
19.Gerard JM. Antibiotic secondary metabolites of bacteria isolated from the marine environment. PhD. Dissertation, 1997; Department of Chemistry, The University of Brithish Columbia, Vancouver, Canada. Available from: https://circle.ubc.ca/handle/2429/6676 [Last accessed on 2011 July 25]  Back to cited text no. 19
    


    Figures

  [Figure 1]
 
 
    Tables

  [Table 1]


This article has been cited by
1 Isocoumarins, miraculous natural products blessed with diverse pharmacological activities
Russell Aamer Saeed
European Journal of Medicinal Chemistry. 2016;
[Pubmed] | [DOI]
2 Bacterial Communities of the Gorgonian Octocoral Pseudopterogorgia elisabethae
Hebelin Correa,Brad Haltli,Carmenza Duque,Russell Kerr
Microbial Ecology. 2013; 66(4): 972
[Pubmed] | [DOI]
3 Antiviral activity of Bacillus sp. isolated from the marine sponge petromica citrina against bovine viral diarrhea virus, a surrogate model of the hepatitis C virus
Santiago Bastos, J.C. and Konecny Kohn, L. and Fantinatti-Garboggini, F. and Aiello Padilla, M. and Furtado Flores, E. and da Silva, B.P. and de Menezes, C.B.A. and Weis Arns, C.
Viruses. 2013; 5(5): 1219-1230
[Pubmed]
4 Antiviral Activity of Bacillus sp. Isolated from the Marine Sponge Petromica citrina against Bovine Viral Diarrhea Virus, a Surrogate Model of the Hepatitis C Virus
Juliana Bastos,Luciana Kohn,Fabiana Fantinatti-Garboggini,Marina Padilla,Eduardo Flores,BŠrbara da Silva,ClŠudia de Menezes,Clarice Arns
Viruses. 2013; 5(5): 1219
[Pubmed] | [DOI]
5 Antitrypanosomal alkaloids from the marine bacterium Bacillus pumilus
Martínez-Luis, S. and Gómez, J.F. and Spadafora, C. and Guzmán, H.M. and Gutiérrez, M.
Molecules. 2012; 17(9): 11146-11155
[Pubmed]



 

Top
 
 
  Search
 
    Similar in PUBMED
   Search Pubmed for
   Search in Google Scholar for
 Related articles
    Access Statistics
    Email Alert *
    Add to My List *
* Registration required (free)  

 
  In this article
    Abstract
    Materials and Me...
    Results and Disc...
   Acknowledgments
    References
    Article Figures
    Article Tables

 Article Access Statistics
    Viewed1481    
    Printed69    
    Emailed0    
    PDF Downloaded51    
    Comments [Add]    
    Cited by others 5    

Recommend this journal