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See detailThe role of protein modifications in senescence of freeze-dried Acetobacter senegalensis during storage
Shafiei, Rasoul ULg; Zarmehrkhorshid, Raziyeh ULg; Bentaib, Azeddine ULg et al

in Microbial Cell Factories (2014)

Background Loss of viability is one of the most important problems during starter culture production. Previous research has mostly focused on the production process of bacterial starters, but there are ... [more ▼]

Background Loss of viability is one of the most important problems during starter culture production. Previous research has mostly focused on the production process of bacterial starters, but there are few studies about cellular protein deterioration causing cell defectiveness during storage. In the present study, we investigated the influence of storage temperature (−21, 4, 35°C) on the cellular protein modifications which may contribute to the senescence of freeze-dried Acetobacter senegalensis. Results Heterogeneous populations composed of culturable cells, viable but non-culturable cells (VBNC) and dead cells were generated when freeze-dried cells were kept at −21 and 4°C for 12 months whereas higher storage temperature (35°C) mainly caused death of the cells. The analysis of stored cell proteome by 2D-DiGE demonstrated a modified pattern of protein profile for cell kept at 4 and 35°C due to the formation of protein spot trains and shift of Isoelectric point (pI). Quantification of carbonylated protein by ELISA showed that the cells stored at 4 and 35°C had higher carbonylated protein contents than fresh cells. 2D-DiGE followed by Western blotting also confirmed the carbonylation of cellular proteins involved in translation process and energy generation. The auto-fluorescent feature of cells kept at 35°C increased significantly which may be an indication of protein glycation during storage. In addition, the percentage of cellular unsaturated fatty acid and the solubility of cellular proteins decreased upon storage of cells at higher temperature suggesting that peroxidation of fatty acids and possibly protein lipidation and oxidation occurred. Conclusions High storage temperature induces some deteriorative reactions such as protein oxidation, lipidation and glycation which may cause further protein modifications like pI-shift, and protein insolubility. These modifications can partly account for the changes in cell viability. It can also be deduced that even moderate carbonylation of some critical cellular proteins (like ribosomal proteins) may lead to VBNC formation or death of freeze-dried bacteria. Moreover, it seems that other mechanisms of biomolecule deterioration preceding protein carbonylation lead to VBNC formation under very low storage temperature. [less ▲]

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See detailTechnologie de production de masse d’insectes - INSECTECH
Richard, Gaetan ULg; Hance, Thierry; Fauconnier, Marie-Laure ULg et al

Report (2014)

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See detailCharacterization of Lactobacillus strains isolated from Algerian children faeces for their probiotic properties
Bahri, F.; Lejeune, Annick ULg; Dubois-Dauphin, R. et al

in African Journal of Microbiology Research [=AJMR] (2014), 8(3), 297-303

Lactic acid bacteria termed probiotics have preventive as well as curative effects on several types of diarrhoea of different aetiologies. The main objective of this study was to screen lactobacilli ... [more ▼]

Lactic acid bacteria termed probiotics have preventive as well as curative effects on several types of diarrhoea of different aetiologies. The main objective of this study was to screen lactobacilli strains having probiotic traits, isolated from Algerian healthy children faeces on the purpose of using them further in children diarrheal illnesses. One hundred and twenty (120) lactic acid bacteria isolates were selected from faecal samples of healthy Algerian children aged between five and ten years. Gram positive rods and catalase negative bacteria (52 isolates) were screened, in vitro, for their probiotic potential properties including ability to survive in simulated gastro-intestinal conditions, adherence to Caco-2 cells and their antimicrobial activity. The results show that only five strains resisted in simulated gastric juice at pH 1.5 and pepsin. Four of them were resistant to simulated intestinal conditions at pH 8 and pancreatin and have a good adherence. In the end, three of them were retained as they display interesting probiotic profiles characterized by a strong antimicrobial effect against some intestinal pathogenic bacteria. They were identified by 16S rDNA sequencing as Lactobacillus plantarum F12, Lactobacillus brevis G6 and Lactobacillus paracasei B13. [less ▲]

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See detailIsolation of an amylolytic chrysophyte, Poterioochromonas sp. from the digestive tract of the termite R. santonensis
Tarayre, Cédric ULg; Bauwens, Julien ULg; Brasseur, Catherine ULg et al

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (2014), 18(1),

The aim of this work was the isolation and cultivation of amylolytic protists living in the digestive tract of the termite Reticulitermes santonensis (Feytaud). A chrysophyte identified as ... [more ▼]

The aim of this work was the isolation and cultivation of amylolytic protists living in the digestive tract of the termite Reticulitermes santonensis (Feytaud). A chrysophyte identified as Poterioochromonas sp. was isolated in a special medium containing rice grains as a source of carbon and nitrogen. Then, the protist was grown in a medium containing starch as a carbon source, tryptone, and a phosphate buffer at different pH values (5, 6 and 7). Yeast extract was added or not. Ciprofloxacin was used to avoid the bacterial development. Other antibiotics were also tested but showed an inhibitive effect on the growth of Poterioochromonas sp. Yeast extract allowed reaching 1.9 (pH 5), 2.3 (pH 6) and 2.2 (pH 7) times higher final cell concentrations, and 2.8 (pH 5), 2.8 (pH 6) and 2.2 (pH 7) times higher biomass yields. The starch concentration did not decrease in the medium until 3 and 4 days of culture, with and without yeast extract, respectively. Eight days of culture were necessary for hydrolyzing the starch completely, with and without yeast extract. Maltose and maltotriose were detected in the culture media and were hydrolyzed progressively. Maximal maltose concentrations were 0.68, 0.66 and 0.51 g.l-1 in the medium containing yeast extract. Maltotriose concentrations were only 0.17, 0.14 and 0.12 g.l-1. Other glucose oligomers were also detected but in lower quantities. It was determined that the protist developed a weak amylase activity, particularly at a weakly acidic pH (5-6). Such a pH also allowed a better growth of the protist. A maximal amylase activity of 112 nkat.l-1 was measured with yeast extract at pH 5. No other enzymatic activity (protease, cellulase or xylanase) was detected except amylase. The degradation products of starch which were obtained by enzymatic hydrolysis allow the identification of α-amylase, amyloglucosidase and possibly β-amylase activities. [less ▲]

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See detailMesophilic biohydrogen production by Clostridium butyricum CWBI1009 in trickling biofilter reactor
Puhulwella, Rathnasiri G.; Beckers, Laurent; Delvigne, Frank ULg et al

in International Journal of Hydrogen Energy (2014), (0),

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See detailHigh-energy X-ray tomography analysis of a metal packing biofilm reactor for the production of lipopeptides by Bacillus subtilis
Zune, Quentin ULg; Soyeurt, Delphine; Toye, Dominique ULg et al

in Journal of Chemical Technology & Biotechnology (2014), 89

BACKGROUND: Whereas multi-species biofilm reactors are commonly used for the treatment of liquid and solid wastes, new strategies are progressing for the development of single species biofilm for the ... [more ▼]

BACKGROUND: Whereas multi-species biofilm reactors are commonly used for the treatment of liquid and solid wastes, new strategies are progressing for the development of single species biofilm for the production of high-value metabolites. Technically, this new concept relies on the design of bioreactors able to promote biofilm formation and on the identification of the key physico-chemical parameters involved in biofilm formation. RESULTS: An experimental setting comprising a liquid continuously recirculated on a metal structured packing has been used to promote Bacillus subtilis GA1 biofilm formation. The colonization of the packing has been visualized non-invasively by X-ray tomography. This analysis revealed an uneven, conical, distribution of the biofilm inside the packing. Compared with a submerged culture carried out in a stirred tank reactor, significant modification of the lipopeptide profile has been observed in the biofilm reactorwith the disappearance of fengycin and iturin fractions and an increase of the surfactin fraction. In addition, considering the biofilm reactor design, no foam formation has been observed during the culture. CONCLUSIONS: The configuration of this biofilm reactor set-up allows for a higher surfactin production by comparison with a submerged culture while avoiding foam formation. Additionally, scale-up could easily be performed by increasing the number of packing elements. [less ▲]

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See detailIn Vitro and In Vivo Characterization of Plant Growth Promoting Bacillus Strains Isolated from Extreme Environments of Eastern Algeria.
Ait-Kaki, Asma; Kacem-Chaouche, Noreddine; Ongena, Marc ULg et al

in Applied biochemistry and biotechnology (2014), 172

This report is to our knowledge the first to study plant growth promotion and biocontrol characteristics of Bacillus isolates from extreme environments of Eastern Algeria. Seven isolates of 14 (50 %) were ... [more ▼]

This report is to our knowledge the first to study plant growth promotion and biocontrol characteristics of Bacillus isolates from extreme environments of Eastern Algeria. Seven isolates of 14 (50 %) were screened for their ability to inhibit growth of some phytopathogenic fungi on PDA and some roots exudates. The bacteria identification based on 16S r-RNA and gyrase-A gene sequence analysis showed that 71 % of the screened isolates belonged to Bacillus amyloliquefaciens and the rest were closely related to B. atrophaeus and B. mojavensis. Most of them had high spore yields (22 x 108-27 x 108 spores/ml). They produced protease and cellulase cell wall-degrading enzymes while the chitinase activity was only observed in the B. atrophaeus (6SEL). A wide variety of lipopeptides homologous was detected by liquid chromatography-electrospray ionization-mass spectrometry analysis. Interestingly, some additional peaks with new masses were characterized, which may correspond to new fengycin classes. The isolates produced siderophores and indole-3- acetic acid phytohormone. The greenhouse experiment using a naturally infested soil with Sclerotonia sclerotiorum showed that the B. atrophaeus (6SEL) significantly increased the size of the chickpea plants and reduced the stem rot disease (P < 0.05). These results suggest that these isolates may be used further as bio-inoculants to improve crop systems. [less ▲]

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See detailPlant defense stimulation by natural isolates of Bacillus depends on efficient surfactin production
Cawoy, Hélène ULg; Mariutto, Martin; Henry, Guillaume et al

in Molecular Plant-Microbe Interactions [=MPMI] (2014), 27

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See detailImprovement of fermentative biohydrogen production by Clostridium butyricum CWBI1009 in sequenced-batch, horizontal fixed bed and biodisc-like anaerobic reactors with biomass retention
Hiligsmann, Serge ULg; Beckers, Laurent; Masset, Julien et al

in International Journal of Hydrogen Energy (2014), 39

A horizontal tubular fixed bed bioreactor (HFBR) and an anaerobic biodisc-like reactor (AnBDR) were designed to both fix Clostridium biomass and enable rapid transfer of the hydrogen produced to gas phase ... [more ▼]

A horizontal tubular fixed bed bioreactor (HFBR) and an anaerobic biodisc-like reactor (AnBDR) were designed to both fix Clostridium biomass and enable rapid transfer of the hydrogen produced to gas phase in order to decrease the strong effect of H2 partial pressure and H2 supersaturation on the performances of Clostridium strains. The highest H2 production rate (703 mL H2/L.h) and yield (302 mL/g glucose consumed i.e. 2.4 mol/mol) with the pure culture were recorded in the AnBDR with 300 mL culture medium (total volume 2.3 L) at pH 5.2 and a glucose loading rate of 2.87 g/L.h. These results are about 2.3 and 1.3-fold higher than those achieved in the same bioreactor with 500 mL liquid medium and with the same glucose consumption rate. Therefore, our experimentations and a short review of the literature reported in this paper emphasize the relevance of performing bioreactors with high L/G transfer. [less ▲]

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See detailDoes the facultative bacteria Serratia symbiotica influence the foraging strategies of aphid parasitoids?
Attia, Sabrine; Louâpre, Philippe; Foray, Vincent et al

Poster (2014)

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See detailLack of isocitrate lyase in Chlamydomonas leads to changes in carbon metabolism and in the response to oxidative stress under mixotrophic growth.
Plancke, Charlotte; Vigeolas, Hélène ULg; Hohner, Ricarda et al

in The Plant journal : for cell and molecular biology (2014), 77(3), 404-417

Isocitrate lyase is a key enzyme of the glyoxylate cycle. This cycle plays an essential role in cell growth on acetate, and is important for gluconeogenesis as it bypasses the two oxidative steps of the ... [more ▼]

Isocitrate lyase is a key enzyme of the glyoxylate cycle. This cycle plays an essential role in cell growth on acetate, and is important for gluconeogenesis as it bypasses the two oxidative steps of the tricarboxylic acid (TCA) cycle in which CO2 is evolved. In this paper, a null icl mutant of the green microalga Chlamydomonas reinhardtii is described. Our data show that isocitrate lyase is required for growth in darkness on acetate (heterotrophic conditions), as well as for efficient growth in the light when acetate is supplied (mixotrophic conditions). Under these latter conditions, reduced acetate assimilation and concomitant reduced respiration occur, and biomass composition analysis reveals an increase in total fatty acid content, including neutral lipids and free fatty acids. Quantitative proteomic analysis by 14 N/15 N labelling was performed, and more than 1600 proteins were identified. These analyses reveal a strong decrease in the amounts of enzymes of the glyoxylate cycle and gluconeogenesis in parallel with a shift of the TCA cycle towards amino acid synthesis, accompanied by an increase in free amino acids. The decrease of the glyoxylate cycle and gluconeogenesis, as well as the decrease in enzymes involved in beta-oxidation of fatty acids in the icl mutant are probably major factors that contribute to remodelling of lipids in the icl mutant. These modifications are probably responsible for the elevation of the response to oxidative stress, with significantly augmented levels and activities of superoxide dismutase and ascorbate peroxidase, and increased resistance to paraquat. [less ▲]

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See detailThe facultative bacterial symbiont Serratia symbiotica in Acyrtosiphon pisum confer resistance to Aphidius ervi
Attia, Sabrine; Foray, Vincent; Louâpres, Philippe et al

Poster (2014)

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See detailValorisation et propriétés des substances humiques des lixiviats de décharge
Tahiri, Abdelghani ULg; Destain, Jacqueline ULg; Thonart, Philippe ULg et al

Conference (2013, December 18)

Des expérimentations ont été menées dans notre laboratoire en utilisant des substances humiques (SH) extraites des lixiviats de cEntre d’Enfouissemnt Techique et des une formulation stable de SH « ... [more ▼]

Des expérimentations ont été menées dans notre laboratoire en utilisant des substances humiques (SH) extraites des lixiviats de cEntre d’Enfouissemnt Techique et des une formulation stable de SH « Humifirst » (12%d’acides humiques et 3% d’acides fulviques) de la compagnie TRADECORP s.a. (Espagne) commercialisée sous l’appelation Humifirst en vue d’en étudier leurs effets sur le développement du système racinaire de vitro-plants de bouleau et d’aulne. Les résultats montrent qu‘un traitement à faible concentration (10ppm) pendant la phase d’élongation des racines affecte la formation des racines latérales formée en présence de SH de lixiviat avec une intensité variable selon l’espèce testée. [less ▲]

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See detailEnhancement of thermophillic anaerobic digestion of methane by metal nanoparticles encapsulated in porous silica
Al-Ahmad, Alaa Eddin ULg; Hiligsmann, Serge ULg; Lambert, Stéphanie ULg et al

Poster (2013, December 05)

Increased demand and progressive depletion of fossil fuels, and worldwide concerns about greenhouse gas emissions have resulted in the development of promising technologies for renewable energy production ... [more ▼]

Increased demand and progressive depletion of fossil fuels, and worldwide concerns about greenhouse gas emissions have resulted in the development of promising technologies for renewable energy production. Therefore, potential alternatives for energy generation are intensively studied. One option is the use of biomass feedstock for the production of biogas through anaerobic digestion. This process is a biochemical technological process for the treatment of a wide range of feedstocks (e.g. organic fraction of municipal waste, animal manure and slurry, agricultural crops, etc.) to produce methane-rich biogas which can be used in replacement of fossil fuels in both heat and power generation and as a vehicle fuel. However, there are critical issues, which need to be addressed to make the production of bio-methane techno-economically viable and ecologically acceptable. One of the most important issues is the effect of trace metals addition on anaerobic digestion. These metals can be stimulatory, inhibitory, or even toxic for biochemical reactions, depending on their concentrations. As reported in literature, Ni, Co and Fe are all involved in the methane production biochemical process and serve as cofactors in enzymes which are involved in the biochemistry of methane formation (Zandvoort et al., 2006). Recently, enormous interest has been focused on biological applications of metal nanoparticles NPs due to their small size, high specified surface and their great potential in application to many science fields. The most studied process concerns zero valent palladium and iron NPs improving anaerobic biodegradation of chlorinated hydrocarbons (Windt et al., 2005). Moreover, investigation carried out in our lab showed that iron NPs encapsulated in silicate matrix may enhance hydrogen production by Clostridium butyricum (Beckers et al., 2013). Nevertheless the influences of metal NPs on methane producing anaerobic digestion have seldom been investigated. The present work investigates the enhancement effect of seven different metal NPs on methane production during the thermophilic anaerobic digestion. NPs of Cu, Pd, Pt, Ni, Co, Ag and Fe encapsulated in porous silica (SiO2) to prevent their coagulation and agglomeration, were added at concentration of 10-5mol/L in batch test (125ml serum bottles containing 70mL culture medium with 5g/L acetate monohydrate as the sole carbon substrate. Nickel, cobalt and iron NPs improved methane production from acetate. To confirm the previous results, the NPs were tested at different concentrations (10-4, 10-5, and 10-6 mol/L) with starch and glucose substrates. The results show that the impact increases with the increase of NPs concentrations up to 10-4 mol/L. The modified Gompertz equation was applied to describe the effect of NPs on anaerobic digestion. According to this model, the kinetic of methane production was particularly affected by nanoparticles addition. The values of the maximum methane production rate MPR (ml/day) was significantly higher 72.5% with nickel NPs at a concentration of 10-4 mol/L than the control without NPs. [less ▲]

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See detailTandem MS of -new- antibiotics from Bacillus guided by MALDI Mass Spectrometry Imaging
Debois, Delphine ULg; Jourdan, Emmanuel; Cawoy, Hélène ULg et al

Conference (2013, December 05)

Generally, an antibiotic is thought to have a role in antagonism simply because the producing strain is known to exhibit a potential for pathogen growth inhibition. Some genetic approaches such as PCR ... [more ▼]

Generally, an antibiotic is thought to have a role in antagonism simply because the producing strain is known to exhibit a potential for pathogen growth inhibition. Some genetic approaches such as PCR using specific primers or genome mining using known sequence data of close relatives are also used. Nevertheless, none of these methods allows stating for a link between a specific compound and the observed antagonism. Yet MALDI Mass Spectrometry Imaging (MSI) is a powerful tool to decipher the chemical messengers exchanged by two protagonists [1,2,3;]. Tandem mass spectrometry (MS/MS) may be also used, either on extracts [2,3] or directly on the microbial colonies [4]. The presentation will thus be focused on two examples of application of MALDI MSI combined to in situ tandem mass spectrometry. The first presented case will be the antagonism between soilborne strain Paenibacillus polymyxa Pp56 and the fungal phytopathogen Fusarium oxysporum. Using MALDI MSI, we were able to precisely localize each detected antibiotic, allowing discriminating which LI-F lipopeptides (fusaricidin) were really active against the pathogen progression. Besides, the use of in situ MS/MS allowed us to sequence the peptide moiety of several LI-F lipopeptides, showing that some of them are actually a mixture of several forms. The second example concerns the metabolites that are released by Bacillus amyloliquefaciens S499 cells following their inoculation on 7 days old tomato roots. We developed specific bioassays for time-course monitoring by MALDI MSI. First analyses revealed an efficient secretion of surfactin by Bacillus cells after 3 days when colonization as biofilm-structured populations is well established. Even if the composition of antibiotic mixture does not greatly evolve over time, after long incubation periods (32 or 35 days post inoculation), new series of compounds are detected in the tomato root -surrounding medium. Structural analysis based on exact mass measurements and MS/MS experiments, performed directly on the semi-solid agar medium, allowed us to identify these compounds as new variants of surfactins. [1] Barger, S., et al., Anton Leeuw Int J G, 2012, 102, 435-445. [2] Hoefler, B. C., et al,. Natl Acad Sci USA, 2012, 109, 13082-13087. [3] Moree, W. J., et al., Natl Acad Sci USA, 2012, 109, 13811-13816. [4] Debois, D., et al., J Am Soc Mass Spectrom. 2013, 24, 1202-1213 [less ▲]

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See detailTechnologie de production de masse d’insectes - INSECTECH
Richard, Gaetan ULg; Hance, Thierry; Fauconnier, Marie-Laure ULg et al

Report (2013)

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See detailShort communication - Isolation of amylolytic, xylanolytic, and cellulolytic microorganisms extracted from the gut of the termite Reticulitermes santonensis by means of a micro-aerobic atmosphere
Tarayre, Cédric ULg; Brognaux, Alison ULg; Bauwens, Julien ULg et al

in World Journal of Microbiology & Biotechnology (2013)

The aim of this work was to isolate enzyme-producing microorganisms from the tract of the termite Reticulitermes santonensis. The microorganisms were extracted from the guts and anaerobic (CO2 or CO2/H2 ... [more ▼]

The aim of this work was to isolate enzyme-producing microorganisms from the tract of the termite Reticulitermes santonensis. The microorganisms were extracted from the guts and anaerobic (CO2 or CO2/H2) and micro-aerobic atmospheres were used to stimulate growth. Three different strategies were tried out. First, the sample was spread on Petri dishes containing solid media with carboxymethylcellulose, microcrystalline cellulose or cellobiose. This technique allowed us to isolate two bacteria: Streptomyces sp. strain ABGxAviA1 and Pseudomonas sp. strain ABGxCellA. The second strategy consisted in inoculating a specific liquid medium containing carboxymethylcellulose, microcrystalline cellulose, or cellobiose. The samples were then spread on Petri dishes with the same specific medium containing carboxymethylcellulose, microcrystalline cellulose, or cellobiose. This led to the isolation of the mold Aspergillus sp. strain ABGxAviA2. Finally, the third strategy consisted in heating the first culture and spreading samples on agar plates containing rich medium. This led to the isolation of the bacterium Bacills subtilis strain ABGx. All those steps were achieved in controlled atmospheres. The four enzyme-producing strains which were isolated were obtained by using a micro-aerobic atmosphere. Later, enzymatic assays were performed on the four strains. Streptomyces sp. strain ABGxAviA1 was found to produce only amylase, while Pseudomonas sp. strain ABGxCellA was found to produce β-glucosidase as well. Aspergillus sp. strain ABGxAviA2 showed β-glucosidase, amylase, cellulase, and xylanase activities. Finally, Bacillus subtilis strain ABGx produced xylanase and amylase. [less ▲]

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See detailPeptidomic comparison and characterization of the major components of the venom of the giant ant Dinoponera quadriceps collected in four different areas of Brazil.
Cologna, Camila Takeno; Cardoso, Jaqueline Dos Santos; Jourdan, Emmanuel et al

in Journal of Proteomics (2013), 94

Despite the noxious effects inflicted by Dinoponera ant's envenomation, the information about the biological properties and composition of their venom is still very limited. Ants from the genus Dinoponera ... [more ▼]

Despite the noxious effects inflicted by Dinoponera ant's envenomation, the information about the biological properties and composition of their venom is still very limited. Ants from the genus Dinoponera are believed to be the world's largest living ants with a body length of 3cm. Their occurrence is restricted to tropical areas of South America. In this work, we study the venom of the giant Dinoponera quadriceps ant collected in 4 different regions of Brazil. By using a combination of complementary mass spectrometric approaches, we aim at: (i) characterizing the venom composition of these ants; (ii) establishing a comparative analysis of the venom from four geographically different regions in Brazil. This approach demonstrates that ant venom is a copious source of new compounds. Several peptides were identified and selected for "de novo sequencing". Since most of the new peptides showed similarities with antimicrobial peptides (AMPs), antimicrobial assays were performed with the purpose of evaluating their activity. In regard to the comparative study of the four regions, we observed not only major differences in the venom compositions, but also that the venoms collected in closest areas are more similar than the ones collected in distant regions. These observations seem to highlight an adaption of the ant venoms to the local environment. Concerning the biological assays, the peptides called Dq-3162 and Da-3177 showed a wide-ranging antimicrobial activity. The characterization of new AMPs with a broad spectrum of activity and different scaffolds may aid scientists to design new therapeutic agents and understand the mechanisms of those peptides to interact with microbial membranes. The results obtained betoken the biotechnological potential of ant's venom. BIOLOGICAL SIGNIFICANCE: For the first time this manuscript describes an extensive proteomics characterization of the D. quadriceps venom. In addition this study reports the variation in venom composition of primitive ants from 4 geographically different areas of Brazil. The results reveal the presence of ~335 compounds for each venom/area and inter-colony variations were observed. 16 new peptides were characterized and 2 of them were synthesized and biologically assayed. These findings highlight the considerable and still unexplored diversity of ant's venom which could be used as valuable research tools in different areas of knowledge. [less ▲]

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