Many high-reading journals reject several studies based on the basic aspects of microbiology by forgetting that this could open doors and windows of great scientific discoveries. A new spore-forming bacteria species called Lysinibacillus louembei has been previously discovered in our research unit. This new study aims to assess a real enzymatic machine produced with such bacteria. Using agarose mixed with half skimmed milk, LB medium supplemented with tween 20, Olive oil, egg yolk, cellulose, casein, pectin and starch, we showed that L. louembei has lipolytic, proteolytic (2.8 cm ± 0.1), cellulolytic, amylolytic pectinolytic activities, with percentage ranging from 30% to 80%. This species is able to secrete lipase, thermostable protease up to 60˚C. Cellulase, pectinase and amylase are secreted with more stability between 30˚C and 50˚C with an optimum at 45˚C. The effect of pH was determined after 24 h of incubation at 37˚C and 50˚C. The proteolytic activity is stable at pH 8 at 50˚C.

Fermented beverages have continued to give more surprises in terms of the presence of biomolecules and the diversity of microorganisms that may be contained. Republic of Congo is home to a panoply of fermented foods and beverages that are still not yet studied. This is the case of plantain wine fluently called banana wine. Within this framework, this work aims to study the role of Biosurfactant-like Biomolecules secreted during fermentation of plantain wine. Using MRS medium, 15 isolates bacteria have been found. 100% are able to secrete biosurfactant and 66.66% are extractible biosurfactants. 33% of isolates have been associated to Lactobacillus plantarum (Is2, Is9, Is12 and Is13) by using a one-step multiplex PCR that targets genes encoding for bacteriocins. Biosurfactants secreted by L. plantarum play an important role in the preservation of banana wine. The biosurfactants extracted with chloroform and ammonium sulphate are able to inhibit the growth of pathogenic bacteria including Shigella flexneri, Salmonella spp., Pseudomonas aeruginosa and Staphylococcus aureus.

Biosurfactants are amphipathic molecules produced by many microorganisms, usually bacteria, fungi, and yeasts. They possess the property of reducing the tension of the membrane interfaces. No studies have been conducted on Shigella species showing the role of biosurfactant-like molecules (BLM) in pathogenicity. The aim of this study is to assess the ability of Shigella environmental and clinical strains to produce BLM and investigate the involvement of biosurfactants in pathogenicity. Our study has shown that BLM are secreted in the extracellular medium with EI24 ranging from 80% to 100%. The secretion is depending on the type III secretion system (T3SS). Moreover, our results have shown that S. flexneri, S. boydii, and S. sonnei are able to interact with hydrophobic areas with 17.64%, 21.42%, and 22.22% hydrophobicity, respectively. BLM secretion is totally prevented due to inhibition of T3SS by 100 mM benzoic and 1.5 mg/ml salicylic acids. P. aeruginosa harboring T3SS is able to produce 100% of BLM in the presence or in the absence of both T3SS inhibitors. The secreted BLM are extractable with an organic solvent such as chloroform, and this could entirely be considered a lipopeptide or polypeptide compound. Secretion of BLM allows some Shigella strains to induce multicellular phenomena like “swarming.”

11Biosurfactants are amphipathic molecules produced by many microorganisms, usually bacteria, 12 fungi and yeasts. They possess the property of reducing the tension of the membrane interfaces. 13 No studies have been conducted on Shigella species showing their involvement of biosurfactant 14 like molecules (BLM) in pathogenicity. This study aims to show that environmental and clinical 15 strains of Shigella are able to produce BLM by emulsifying gasoline and diesel fuels. Our study 16 has shown that BLM are secreted in the extracellular medium with EI24 ranging from 80 to 17 100%. The secretion is depending on the type III secretion system (T3SS). We did show that S. 18 flexneri, S. boydii and S. sonnei are able to interact with hydrophobic areas with respectively 19 17.64%, 21.42% and 22.22% of hydrophobicity. 100 mM Benzoic and 1.5mg/mL Salycilic 20 acids have been inhibited T3SS and this totally stops the BLM secretion. Pseudomonas 21 aeruginosa which has T3SS is able to produce 100% of BLM in the presence or in the absence 22 of both T3SS inhibitors. The secreted BLM is extractable with an organic solvent such as 23 chloroform and could entirely be considered like lipopeptide or polypeptidic compound. By 24 secreting BLM, Shigella is able to perform multicellular phenomena like "swarming" allowing 25 to invade and disseminate inside epithelial cells. 26 Introduction 28 The ingestion of pathogenic and virulent microorganisms generally affecting peoples in both 29 developed and developing countries [1]. Shigella is one of the Gram-negative bacterium 30 belonging to Enterobacteriaceae family and is causative agent of bacillary dysentery or 31 shigellosis [2]. The genus Shigella was the major pathogen bacteria associated with dysentery 32with attributable fraction to 63,8%, but also the second most common pathogen associated with 33 watery diarrhoea with attributable fraction to 12,9% in sub-Saharan Africa and south Asia. 34 Children under 5 years are the most affected. More and more shigellosis is a pathology that 35 both towards neglected diseases but 164300 of death per years have been notified all over the 36 world in 2010. Most deaths occur in sub-Saharan Africa and in south Asia [3-6]. This is include 37 Republic of Congo and surprisingly no epidemiological studies have been conducted in this 38 field. The genus Shigella includes four species (S. flexneri, S. sonnei, S. dysenteriae and S. 39 boydii) [7]. 10 bacteria of S. dysenteriae type 1 and 100 to 180 bacteria of S. flexneri or S. 40 sonnei are enough to produce symptomatic infection [8].41Shigella's pathogenicity is based on a virulence plasmid pWR100 in which the mxi-spa locus 42 encodes the type three secretion system(T3SS) involved in effector production like IpaB, C and 43 D (Translocator and Tip) to invade host cell [9][10][11][12]. A previous study in our laboratory that 44 showed that Shigella sp. isolated from Brazzaville wastewater were able to emulsify 45 hydrocarbon from gasoline and/or diesel fuel [13]. Sachin et al. found the same pr...

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