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This study aims to evaluate the in silico genomic characteristics of Streptococcus infantarius subsp. infantarius, isolated from Coalho cheese from Paraíba, Brazil, with a view to application in lactic fermentations. rRNA sequences from the 16S ribosomal region were used as input to GenBank, in the search for patterns that could reveal a non-pathogenic behavior of S. infantarius subsp. infantarius, comparing mobile genetic elements, antibiotic resistance genes, pan-genome analysis and multi-genome alignment among related species. S. infantarius subsp. infantarius CJ18 was the only complete genome reported by BLAST/NCBI with high similarity and after comparative genetics with complete genomes of Streptococcus agalactiae (SAG153, NJ1606) and Streptococcus thermophilus (ST106, CS18, IDCC2201, APC151) revealed that CJ18 showed a low number of transposases and integrases, infection by phage bacteria of the Streptococcus genus, absence of antibiotic resistance genes and presence of bacteriocin, folate and riboflavin producing genes. The genome alignment revealed that the collinear blocks of S. thermophilus ST106 and S. agalactiae SAG153 have inverted blocks when compared to the CJ18 genome due to gene positioning, insertions and deletions. Therefore, the strains of S. infantarius subsp. infantarius isolated from Coalho cheese from Paraíba showed genomic similarity with CJ18 and the mobility of genes analyzed in silico showed absence of pathogenicity throughout the genome of CJ18, indicating the potential of these strains for the dairy industry.

Fibrinolytic proteases are a promising alternative in the pharmaceutical industry, they are used in the treatment of cardiovascular diseases, especially thrombosis. Microorganisms are the most interesting source of fibrinolytic proteases. The aim of this study was the production of fibrinolytic protease from Streptomyces parvulus DPUA 1573, the recovery of the protease by aqueous two-phase system and partial biochemical characterization of the enzyme. The aqueous two-phase system was performed according to a 24-full factorial design using polyethylene glycol molar mass, polyethylene glycol concentration, citrate concentration and pH as independent variables. It was analyzed the effect of different ions, surfactants, inhibitors, pH and temperature on enzyme activity. The best conditions for purifying the enzyme were 17.5% polyethylene glycol 8,000, 15% Phosphate and pH 8.0, it was obtained a partition coefficient of 7.33, a yield of 57.49% and a purification factor of 2.10-fold. There was an increase in enzyme activity in the presence of Fe2+ and a decrease in the presence of $\beta$-Mercaptoethanol, phenylmethylsulfonyl fluoride and Iodoacetic acid. The optimum pH was 7.0 and the optimum temperature was 40 ºC. The purified protease exhibited a molecular mass of 41 kDa. The fibrinolytic protease from Streptomyces parvulus proved to be a viable option for the development of a possible drug with fibrinolytic action.

The Cladosporium genus, defined by Link in 1816, is one of the largest and most heterogeneous Hyphomycetes genus. It comprises more than 189 species still rarely explored biotechnologically. One of the most studied microbial enzymes, -galactosidase is a glycoside hydrolase enzyme that catalyzes the hydrolysis of -galactosides into monosaccharides through the breaking of a glycosidic bond. Recently, new studies comprising new microbial sources of -galactosidase, presenting biotechnologically interesting characteristics, have been encouraged. In this context, the present study evaluated the production of -galactosidase by a new isolate of Cladosporium tenuissimum. A C. tenuissimum inoculum was prepared adding 107 spore/mL in sterile saline solution 0.85% (w/v) NaCl containing 0.01% (w/v) Tween 80 and added to fermentation medium for enzyme production. The fermentation medium, composed of (% w/v): lactose (2), peptone (0.4), yeast extract (0.4) and salts (KH2PO4 (0.2), Na2HPO4.12H2O (0.8) and MgSO4.7H2O (0.025), pH 6.5, was maintained at 28° C and 180 rpm for 13 days. One sample (50 mL erlenmeyer) was removed every 24 hours and -galactosidase activity was evaluated using ONPG (ortho-Nitrophenyl--galactoside) method. The results showed maximum -galactosidase production by C. tenuissimum URM 7803 on thirteenth day, displayed enzymatic activity of 462.13 U/mL. The C. tenuissimum URM 7803 isolate proved to be a powerful new -galactosidase producer with potential application for food processing., info:eu-repo/semantics/publishedVersion

Chitin and chitosan were extracted from mycelial biomass of Cunninghamella elegans and the performance for copper, lead and iron biosorption in aqueous solution was evaluated. The growth curve of C. elegans was accomplished by determination of biomass, pH, glucose and nitrogen consumption. Chitin and chitosan were extracted by alkali-acid treatment and the yields were 23.8 and 7.8%, respectively. For the adsorption analysis, the process of heavy uptake metal sorption was evaluated using polysaccharides solutions (1% w/v). The rate of metallic biosorption was dependent upon the concentration and pH of metal solutions, and the best results were observed with pH 4.0. Chitosan showed the highest affinity for copper and chitin for iron adsorption. The results suggest that C. elegans (IFM 46109) is an attractive source of production of chitin and chitosan, with a great potential of heavy metals bioremediation in polluted environments. Quitina e quitosana foram extraídas a partir da massa micelial de Cunninghamella elegans (IFM 46109) e avaliou-se a aplicação destes polissacarídeos na remoção dos metais pesados cobre, chumbo e ferro preparados em solução aquosa. O crescimento de C. elegans foi acompanhado através da determinação de biomassa, pH, consumo de glicose e de nitrogênio. A extração de quitina e quitosana realizou-se através de tratamento álcali-ácido e a produção dos polissacarídeos foi de 23,8 e 7,8 %, respectivamente. A avaliação do processo de remoção dos metais pesados foi realizada utilizando-se os polissacarídeos em solução a 1% (p/v). Os níveis de biossorção de metais foram dependentes da concentração e do pH das soluções. Os melhores resultados foram obtidos em pH 4,0. A quitosana mostrou maior índice de biossorção para o íon cobre e a quitina para o ferro. Os resultados sugerem que C.elegans pode ser considerada uma fonte atrativa para a produção alternativa de quitina e quitosana, e que demonstra grande potencial de biossorção de metais pesados em ambientes poluídos.