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1.
Front Immunol ; 15: 1350560, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38863702

RESUMO

Background: Despite decades of effort, Plasmodium falciparum malaria remains a leading killer of children. The absence of a highly effective vaccine and the emergence of parasites resistant to both diagnosis as well as treatment hamper effective public health interventions. Methods and results: To discover new vaccine candidates, we used our whole proteome differential screening method and identified PfGBP130 as a parasite protein uniquely recognized by antibodies from children who had developed resistance to P. falciparum infection but not from those who remained susceptible. We formulated PfGBP130 as lipid encapsulated mRNA, DNA plasmid, and recombinant protein-based immunogens and evaluated the efficacy of murine polyclonal anti-PfGBP130 antisera to inhibit parasite growth in vitro. Immunization of mice with PfGBP130-A (aa 111-374), the region identified in our differential screen, formulated as a DNA plasmid or lipid encapsulated mRNA, but not as a recombinant protein, induced antibodies that inhibited RBC invasion in vitro. mRNA encoding the full ectodomain of PfGBP130 (aa 89-824) also generated parasite growth-inhibitory antibodies. Conclusion: We are currently advancing PfGBP130-A formulated as a lipid-encapsulated mRNA for efficacy evaluation in non-human primates.


Assuntos
Anticorpos Antiprotozoários , Eritrócitos , Vacinas Antimaláricas , Malária Falciparum , Plasmodium falciparum , Proteínas de Protozoários , Animais , Plasmodium falciparum/imunologia , Anticorpos Antiprotozoários/imunologia , Camundongos , Eritrócitos/parasitologia , Eritrócitos/imunologia , Malária Falciparum/imunologia , Malária Falciparum/prevenção & controle , Malária Falciparum/parasitologia , Humanos , Vacinas Antimaláricas/imunologia , Proteínas de Protozoários/imunologia , Proteínas de Protozoários/genética , Antígenos de Protozoários/imunologia , Imunização , Feminino
2.
J Appl Microbiol ; 134(9)2023 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-37660236

RESUMO

Until recently, members of the classical Bordetella species comprised only pathogenic bacteria that were thought to live exclusively in warm-blooded animals. The close phylogenetic relationship of Bordetella with Achromobacter and Alcaligenes, which include primarily environmental bacteria, suggests that the ancestral Bordetellae were probably free-living. Eventually, the Bordetella species evolved to infect and live within warm-blooded animals. The modern history of pathogens related to the genus Bordetella started towards the end of the 19th century when it was discovered in the infected respiratory epithelium of mammals, including humans. The first identified member was Bordetella pertussis, which causes whooping cough, a fatal disease in young children. In due course, B. bronchiseptica was recovered from the trachea and bronchi of dogs with distemper. Later, a second closely related human pathogen, B. parapertussis, was described as causing milder whooping cough. The classical Bordetellae are strictly host-associated pathogens transmitted via the host-to-host aerosol route. Recently, the B. bronchiseptica strain HT200 has been reported from a thermal spring exhibiting unique genomic features that were not previously observed in clinical strains. Therefore, it advocates that members of classical Bordetella species have evolved from environmental sources. This organism can be transmitted via environmental reservoirs as it can survive nutrient-limiting conditions and possesses a motile flagellum. This study aims to review the molecular basis of origin and virulence properties of obligate host-restricted and environmental strains of classical Bordetella.


Assuntos
Bordetella bronchiseptica , Coqueluche , Animais , Pré-Escolar , Cães , Humanos , Bordetella bronchiseptica/genética , Genômica , Mamíferos , Filogenia , Virulência/genética
3.
FEMS Microbiol Lett ; 368(6)2021 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-33856450

RESUMO

Classical Bordetella species are primarily isolated from animals and humans causing asymptomatic infection to lethal pneumonia. However, isolation of these bacteria from any extra-host environmental niche has not been reported so far. Here, we have characterized the genomic plasticity and antibody response of Bordetella bronchiseptica strain HT200, isolated from a thermal spring. Genomic ANI value and SNPs-based phylogenetic tree suggest a divergent evolution of strain HT200 from a human-adapted lineage of B. bronchiseptica. Growth and survivability assay showed strain HT200 retained viability for more than 5 weeks in the filter-sterilized spring water. In addition, genes or loci encoding the Bordetella virulence factors such as DNT, ACT and LPS O-antigen were absent in strain HT200, while genes encoding other virulence factors were highly divergent. Phenotypically, strain HT200 was non-hemolytic and showed weak hemagglutination activity, but was able to colonize in the respiratory organs of mice. Further, both infection and vaccination with strain HT200 induced protective antibody response in mouse against challenge infection with virulent B. bronchiseptica strain RB50. In addition, genome of strain HT200 (DSM 26023) showed presence of accessory genes and operons encoding predicted metabolic functions pertinent to the ecological conditions of the thermal spring.


Assuntos
Formação de Anticorpos , Bordetella bronchiseptica , Fontes Termais , Animais , Anticorpos Antibacterianos/sangue , Formação de Anticorpos/imunologia , Vacinas Bacterianas/imunologia , Bordetella bronchiseptica/genética , Bordetella bronchiseptica/imunologia , Bordetella bronchiseptica/patogenicidade , Variação Genética , Fontes Termais/microbiologia , Camundongos , Polimorfismo de Nucleotídeo Único , Sistema Respiratório/microbiologia , Fatores de Virulência/genética
4.
Chemosphere ; 256: 127126, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32470736

RESUMO

Rapid industrialization and consumption of fossil fuels have led to considerable progress in the production of renewable biofuels like bioethanol. Lignocellulosic biomass such as grasses serves as cheap feedstocks for the production of bioethanol. However, the process involved in lignocellulosic bioethanol production is expensive which restricts its industrial production. The present study thus attempted to investigate a partially consolidated bioprocessing (PCB) approach using two isolated anaerobic thermophiles i.e. Bacillus paranthracis and Bacillus nitratireducens for direct conversion of ultra-sonication assisted sodium hydroxide (UA-NaOH) pretreated Denannath grass to bioethanol in co-culture consortium batch fermentation experiments. The process parameters for the PCB approach were optimized using the Box-Behnken design of Response Surface Methodology (RSM). The parameters that were considered were substrate concentration (5-10 g), incubation time (30-66 h), inoculum volume [1:1 to 3:3 (% v/v) and temperature (50-65 °C). The maximum ethanol concentration of 8.46 mM (0.39 g/L from 7.5 g/L of substrate loading) and ethanol yield (Yp/s) of 0.55 g/g of reducing sugar was obtained at 57.5 °C. In the same conditions the cellulase and xylanase activities were 0.8 U/mL and 11.53 U/mL respectively, while the lactate and acetate concentrations were 0.2 mM (0.009 g/L) and 2.9 mM (0.13 g/L) correspondingly. An increase in the substrate loadings to 250 g/L in a batch fermenter (3 L) resulted in the production of 373.35 mM (17.1 g/L) of ethanol concentration and Yp/s of 0.16 g/g of reducing sugar.


Assuntos
Bacillus/metabolismo , Biocombustíveis/análise , Reatores Biológicos/microbiologia , Etanol/análise , Pennisetum/metabolismo , Anaerobiose , Biomassa , Carboidratos , Celulase/metabolismo , Fermentação , Hidrólise , Hidróxido de Sódio
5.
Microbiol Resour Announc ; 9(8)2020 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-32079632

RESUMO

We report the draft genome sequences of Vibrio alginolyticus strain S6-61 and Vibrio diabolicus strain S7-71, isolated from the corals Pocillopora verrucosa and Fungia danai, respectively. The genomes of strains S6-61 and S7-71 contain 4,880 and 4,641 protein coding genes, respectively, and harbor genes associated with the ectoine biosynthesis pathway.

6.
Microbiol Resour Announc ; 9(1)2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31896635

RESUMO

We report the draft genome sequences of Vibrio fortis strains AN-60 and S7-72, which were isolated from coral (Fungia sp.) from the Andaman Sea. The genome sizes for strains AN-60 and S7-72 are 5.43 and 5.53 Mb, respectively. Both strains harbor genes associated with protocatechuate and azathioprine degradation and the sulfate reduction pathway.

7.
Genome Announc ; 6(10)2018 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-29519829

RESUMO

Marinomonas fungiae strain AN44T was isolated from mucus of the coral Fungia echinata Optimum growth occurs at 3 to 5% NaCl. The draft genome is 4.2 Mb, with 3,776 protein-coding genes. It harbors genes for the degradation of aromatic compounds, such as quinate, ferulate, p-coumarate, protocatechuate, and p-hydroxyphenylacetate.

8.
Genome Announc ; 5(17)2017 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-28450528

RESUMO

Rhizobium pusense strain NRCPB10T was isolated from rhizosphere soil of chickpeas (Cicer arietinum L.). Based upon the draft genome sequence, the genome is 5.28 Mb and encodes 5,064 proteins.

9.
Front Microbiol ; 7: 1896, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27933056

RESUMO

The genus Marinomonas comprises Gram negative bacteria which are widespread in the marine environment and there is no report on the genomic analysis of SXT/R391 ICEs derived from this group of bacteria. This study describes the genomic features of three new SXT/R391 integrating conjugating elements (ICEs) identified in the genome of Marinomonas fungiae JCM 18476T (ICEMfuInd1a and ICEMfuInd1b) and in Marinomonas profundimaris strain D104 (ICEMprChn1). Structural organizations of the three ICEs were similar to the typical SXT/R391 family of ICEs and showed high degree of conservation in the core genes. Sequence analysis revealed ICEMfuInd1b and ICEMprChn1 were inserted into the genome at 5'-end of an typical host prfC gene, while ICEMfuInd1a was inserted at 5'-end of an atypical hipA-like gene. Despite their coexistence, the ICEMfuInd1a and ICEMfuInd1b were not present in a tandem fashion in the genome of M. fungiae. Phylogenetic analyses revealed the three ICEs either evolved independently or high degrees of recombination events had masked their evolution from a common SXT ancestor. Further, we found that the typical entry exclusion mechanism mediated by the TraG/EeX protein pair was likely defective in preventing the conjugative transfer of a second copy of the same S (SXT) group ICE into the M. fungiae genome due to mutations. Our analysis showed the presence of 16, 25, and 27 variable genes in the hotspots of ICEMfuInd1a, ICEMfuInd1b, and ICEMprChn1, respectively, many of which were not reported earlier for SXT/R391 ICEs. Sequence analysis predicted these hotspot regions were shaped by acquisition of genes through homologous recombination between the SXT and R391 related ICEs or mobile genetic elements present in disparate marine bacteria. Multidrug resistance genes which are hallmark feature of SXT/R391 ICEs were not present in either of the two ICEs from M. fungiae but were present within a transposon cassette in the HS-1 of the ICEMprChn1 from M. profundimaris. Finally, our data provided information on the genetic diversity and predicted functions encoded by variable genes present in the hotspot regions of these new ICEs.

10.
Genome Announc ; 4(4)2016 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-27516514

RESUMO

The moderately thermophilic bacterium Chelatococcus sambhunathii strain HT4(T) was isolated from hot spring sediment. Based upon the draft genome sequence, the genome is 4.4 Mb and encodes 4,147 proteins.

11.
Genome Announc ; 4(4)2016 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-27516517

RESUMO

Gulbenkiania indica strain HT27(T) was isolated from a sulfur spring. Here, we report the first representative draft genome sequence of a type strain of the genus Gulbenkiania The estimated genome is 2.8 Mb, with 2,713 protein-coding sequences.

12.
Genome Announc ; 4(4)2016 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-27516520

RESUMO

The genus Comamonas contains species isolated from various environments, such as termite guts, wetlands, activated sludge, soil, humans, and fresh water. Here, we report the draft genome sequence of Comamonas thiooxydans strain S23(T) capable of oxidizing thiosulfate under mixotrophic growth conditions. Based upon draft genome sequencing, the genome is 5.3 Mb and encodes 4,767 proteins. The Comamonas thiooxydans whole-genome sequence will help understand the metabolic diversity in sulfur oxidation pathways.

13.
Front Microbiol ; 7: 936, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27379066

RESUMO

This study describes the community composition and functions of the microbiome associated with the mucus of the coral Fungia echinata based on metagenomic approach. Metagenome sequence data showed a dominance of the class Gammaproteobacteria followed by Alphaproteobacteria, Betaproteobacteria, Deltaproteobacteria, Flavobacteriia, Bacilli, and Clostridia. At the order level, the most abundant groups were Pseudomonadales, Oceanospirillales, Alteromonadales, and Rhodobacterales. The genus Psychrobacter was the most predominant followed by Thalassolituus and Cobetia, although other genera were also present, such as Sulfitobacter, Pseudoalteromonas, Oleispira, Halomonas, Oceanobacter, Acinetobacter, Pseudomonas, Vibrio, and Marinobacter. The metabolic profile of the bacterial community displayed high prevalence of genes associated with core-housekeeping processes, such as carbohydrates, amino acids, proteins, and nucleic acid metabolism. Further, high abundance of genes coding for DNA replication and repair, stress response, and virulence factors in the metagenome suggested acquisition of specific environmental adaptation by the microbiota. Comparative analysis with other coral metagenome exhibits marked differences at the taxonomical and functional level. This study suggests the bacterial community compositions are influenced by the specific coral micro-niche and the oligotrophic marine environment.

14.
Front Microbiol ; 6: 1166, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26579081

RESUMO

This study describes microbial diversity in four tropical hot springs representing moderately thermophilic environments (temperature range: 40-58°C; pH: 7.2-7.4) with discrete geochemistry. Metagenome sequence data showed a dominance of Bacteria over Archaea; the most abundant phyla were Chloroflexi and Proteobacteria, although other phyla were also present, such as Acetothermia, Nitrospirae, Acidobacteria, Firmicutes, Deinococcus-Thermus, Bacteroidetes, Thermotogae, Euryarchaeota, Verrucomicrobia, Ignavibacteriae, Cyanobacteria, Actinobacteria, Planctomycetes, Spirochaetes, Armatimonadetes, Crenarchaeota, and Aquificae. The distribution of major genera and their statistical correlation analyses with the physicochemical parameters predicted that the temperature, aqueous concentrations of ions (such as sodium, chloride, sulfate, and bicarbonate), total hardness, dissolved solids and conductivity were the main environmental variables influencing microbial community composition and diversity. Despite the observed high taxonomic diversity, there were only little variations in the overall functional profiles of the microbial communities in the four springs. Genes involved in the metabolism of carbohydrates and carbon fixation were the most abundant functional class of genes present in these hot springs. The distribution of genes involved in carbon fixation predicted the presence of all the six known autotrophic pathways in the metagenomes. A high prevalence of genes involved in membrane transport, signal transduction, stress response, bacterial chemotaxis, and flagellar assembly were observed along with genes involved in the pathways of xenobiotic degradation and metabolism. The analysis of the metagenomic sequences affiliated to the candidate phylum Acetothermia from spring TB-3 provided new insight into the metabolism and physiology of yet-unknown members of this lineage of bacteria.

15.
FEMS Microbiol Lett ; 338(2): 118-23, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23083057

RESUMO

In this study, we characterize 18 cultivable bacteria associated within the mucus of the coral Fungia echinata from Andaman Sea, India. 16S rRNA gene sequence analysis showed that all the 18 strains isolated in this study from the coral mucus belong to the group Gammaproteobacteria and majority of them were identified as Vibrio core group. Our objective was to investigate the presence of the SXT/R391 integrating conjugative elements (ICEs) targeting integrase int(SXT) and SXT Hotspot IV genetic elements in these isolates. SXT/ICE initially reported in Vibrio cholerae contains many antibiotic and heavy metal resistance genes and acts as an effective tool for the horizontal transfer of resistance genes in other bacterial populations. Two of our strains, AN44 and AN60, were resistant to sulfamethoxazole, trimethoprim, chloramphenicol, and streptomycin, in addition to other antibiotics such as neomycin, ampicillin, rifampicin, and tetracycline. Using PCR followed by sequencing, we detected the SXT/ICE in these strains. The SXT integrase genes of AN44 and AN60 had a 99% and 100% identity with V. cholerae serogroup O139 strain SG24. This study provides the first evidence of the presence of SXT/R391 ICEs in Marinomonas sp. strain AN44 (JCM 18476(T) ) and Vibrio fortis strain AN60 (DSM 26067(T) ) isolated from the mucus of the coral F. echinata.


Assuntos
Antozoários/microbiologia , Bactérias/isolamento & purificação , Microbiologia da Água , Animais , Bactérias/efeitos dos fármacos , Bactérias/genética , Conjugação Genética , Testes de Sensibilidade Microbiana , RNA Ribossômico 16S/genética
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