Publications by authors named "Mario E Lozano"

Baculoviruses are a group of insect viruses with large circular dsDNA genomes exploited in numerous biotechnological applications, such as the biological control of agricultural pests, the expression of recombinant proteins or the gene delivery of therapeutic sequences in mammals, among others. Their genomes encode between 80 and 200 proteins, of which 38 are shared by all reported species. Thanks to multi-omic studies, there is remarkable information about the baculoviral proteome and the temporality in the virus gene expression.

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St. Louis encephalitis virus (SLEV) is a mosquito-borne re-emerging flavivirus in Argentina. It is currently necessary to develop specific serological tests that can efficiently discriminate the flaviviruses that circulate in our country.

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Saint Louis encephalitis virus (SLEV) and West Nile virus (WNV) are two of the major causes of arboviral encephalitis in the Americas. The co-circulation of related flaviviruses in the Americas and prior vaccination against flaviviruses pose problems to the diagnostic specificity of serological assays due to the development of cross-reactive antibodies. An accurate diagnosis method capable of differentiating these related viruses is needed.

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Article Synopsis
  • Two new vaccine candidates for dengue virus were developed by combining the Z protein from Junin virus with two specific peptides from the dengue virus's envelope protein.
  • Testing showed that immunized mice generated a strong immune response, particularly with the Z/DENV-P2 candidate, which produced significant levels of antibodies and reduced viral plaque counts.
  • The study suggests that Z-JUNV can effectively deliver dengue vaccine components, with Z/DENV-P2 showing promise as a protective agent, unlike Z/DENV-P1 which was ineffective.
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Ribavirin is an antiviral compound widely used in Hepatitis C Virus therapy. Biotransformation of this nucleoside analogue using ATCC 12407 as biocatalyst is herein reported. Reaction parameters such as microorganism amounts, substrate ratio and temperature were optimized reaching conversion yields of 86%.

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The Arenaviridae family includes several hemorrhagic fever viruses which are important emerging pathogens. Junín virus, a member of this family, is the etiological agent of Argentine Hemorrhagic Fever (AHF). A collaboration between the Governments of Argentina and the USA rendered the attenuated Junín virus vaccine strain Candid#1.

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Designing degenerate PCR primers for templates of unknown nucleotide sequence may be a very difficult task. In this paper, we present a new method to design degenerate primers, implemented in family-specific degenerate primer design (FAS-DPD) computer software, for which the starting point is a multiple alignment of related amino acids or nucleotide sequences. To assess their efficiency, four different genome collections were used, covering a wide range of genomic lengths: Arenavirus (10 × 10(4) nucleotides), Baculovirus (0.

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Background: Arenavirus matrix protein Z plays an important role in virus budding and is able to generate enveloped virus-like-particles (VLPs) in absence of any other viral proteins. In these VLPs, Z protein is associated to the plasma membrane inner surface by its myristoyl residue. Budding induction and vesicle formation properties can be exploited to generate enveloped VLPs platform.

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This work describes the application of thermophilic microorganisms for obtaining 6-halogenated purine nucleosides. Biosynthesis of 6-chloropurine-2'-deoxyriboside and 6-chloropurine riboside was achieved by Geobacillus stearothermophilus CECT 43 with a conversion of 90% and 68%, respectively. Furthermore, the selected microorganism was satisfactorily stabilized by immobilization in an agarose matrix.

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An efficient and green bioprocess to obtain 2,6-diaminopurine nucleosides using thermophilic bacteria is herein reported. Geobacillus stearothermophilus CECT 43 showed a conversion rate of 90 and 83% at 2 h to obtain 2,6-diaminopurine-2'-deoxyriboside and 2,6-diaminopurine riboside, respectively. The selected biocatalyst was successfully stabilized in an agarose matrix and used to produce up to 23.

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Article Synopsis
  • This study presents a green bioprocess for producing 5-halogenated pyrimidine nucleosides from thymidine using whole cells.
  • Free and immobilized Aeromonas salmonicida demonstrated high conversion rates for synthesizing 5-fluoro-2'-deoxyuridine (floxuridine).
  • The immobilized cells showed stability for over 4 months and could be reused at least 30 times, making them efficient for pharmaceutical applications, particularly as antitumoral agents.
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The Argentine Hemorrhagic Fever, an endemic disease present in a much of Argentina, is caused by the Junín virus (JUNV). Currently, there are sequences available from several strains of this virus, like those belonging to the vaccine lineage (XJ13, XJ#44 and Candid#1), as well as MC2 (rodent isolate) and IV4454 (human isolate). In this article, we report sequence information on two fragments of genomic segment S of viral isolates from the endemic area.

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Introduction: Arenavirus hemorrhagic fever is a severe emerging disease.

Methods: Considering that the levels of antibodies against arenavirus in the Brazilian population are completely unknown, we have standardized an ELISA test for detecting IgG antibodies using a recombinant nucleoprotein from the Junin virus as the antigen. This protein was obtained by inserting the gene of the Junin virus nucleoprotein into the genome of Autographa californica nucleopolyhedrovirus, using the Bac-to-Bac baculovirus expression system.

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The Junín virus strain Candid#1 was developed as a live attenuated vaccine for Argentine hemorrhagic fever. In this article, we report sequence information of the L and S RNAs of Junín virus Candid#1 and XJ#44 strains, and show the comparisons with the XJ13 wild-type strain and with other Junín virus strains, like Romero, IV4454 and MC2 strains, and other closely and distantly related arenaviruses. Comparisons of the nucleotide and amino acid sequences of all genes of three strains from the same vaccine genealogy, revealed different point mutations that could be associated with the attenuated phenotype.

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We have located and cloned the Anticarsia gemmatalis multicapsid nucleopolyhedrovirus isolate 2D (AgMNPV-2D) genomic DNA fragment containing the immediate early 1 ORF and its flanking regions. Computer assisted analysis of the complete ie1 locus nucleotide sequence information was used to locate regulatory signals in the upstream region and conserved nucleotide and amino acid sequences. Comparative studies led to the identification of several characteristic protein motifs and to the conclusion that AgMNPV-2D is more closely related to Choristoneura fumiferana defective NPV than to other Group I nucleopolyhedrovirus.

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Junin virus strain Candid #1 was developed as a live attenuated vaccine for Argentine haemorrhagic fever. In this paper, we report the nucleotide sequences of L RNA of Candid #1 and examine the relationship to its more virulent ancestors Junin virus XJ#44 and XJ 13 (prototype) and other closely and distantly related arenaviruses. Comparisons of the nucleotide and amino acid sequences of L and Z genes of Candid #1 and its progenitor strains revealed twelve point mutations in the L polypeptide that are unique to the vaccine strain.

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The bean shoot borer, Epinotia aporema (Lep. Tortricidae), is an economically important pest of legume crops in South America. Recently, a granulovirus (EpapGV) was isolated from E.

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The gp64 locus of Anticarsia gemmatalis multicapsid nucleopolyhedrovirus isolate Santa Fe (AgMNPV-SF) was characterised molecularly in our laboratory. To this end, we have located and cloned a AgMNPV-SF genomic DNA fragment containing the gp64 gene and sequenced the complete gp64 locus. Nucleotide sequence analysis indicated that the AgMNPV gp64 gene consists of a 1500 nucleotide open reading frame (ORF), encoding a protein of 499 amino acids.

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The ecdysteroid UDP-glycosyltransferase (egt) gene of Epinotia aporema granulovirus (EpapGV) was cloned sequenced and its biological activity was assessed. It encodes a protein of 446 amino acids. Direct evidence that the cloned gene encodes an active EGT protein was obtained by transient expression assays in insect cells.

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The arenavirus nucleocapsid protein (N) is a highly basic 63 kDa protein with a dual function during the virus life-cycle. First, it is involved in essential steps of genome replication, promoting the synthesis of the full-length antigenomic copy of S RNA, and second it associates with the genomic RNA to form the nucleocapsid. We have expressed the N protein of Junín virus in E.

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