The aim of this study was to perform bioinformatics characterization and optimize the production of extracellular L-asparaginase from Bacillus sp. M62, isolated from the Maras salt ponds (Cusco). To achieve this, the production of L-asparaginase was verified by the change in color of modified M9 medium, containing 0.0075% bromophenol blue, at pH 7.4 and 37°C for 72 hours. Genomic DNA was extracted to amplify the 16S ribosomal genes and the ansA3 gene. The amino acid sequence encoded by the ansA3 gene was predicted using bioinformatic analysis. The production of intracellular and extracellular L-asparaginase was evaluated at different levels of glucose, L-asparagine, NaCl, and pH in modified M9 medium. Additionally, the enzymatic activities of L-asparaginase and L-glutaminase were determined by quantifying the released ammonium using the Nessler method. Bacillus sp. M62 showed the change...

El objetivo de esta investigación fue caracterizar bacterias halotolerantes aisladas del proceso de salado-madurado de Engraulis ringens provenientes de una empresa pesquera de Chimbote (Perú). Para ello, se recolectaron tres muestras de pescado al inicio y término del proceso. Se aislaron 14 bacterias halotolerantes, 12 aisladas en medio con NaCl al 5% y dos al 10%. Se evaluó su capacidad de crecimiento a temperaturas de 4 a 50 °C y de 2.5 a 12.5% de NaCl, así como su actividad bioquímica con las pruebas de oxidasa, ureasa, indol, utilización de citrato, fermentación de carbohidratos, hidrólisis de almidón, caseína y gelatina, y su sensibilidad a penicilina, cloranfenicol, gentamicina, tetraciclina, rifampicina, sulfametoxazol/trimetoprima, estreptomicina, ácido nalidíxico y novobiocina. El 71% de las cepas creció entre 25 y 44 °C y hasta 10% de NaCl, y presentaron acti...

L-asparaginase (EC 3.5.1.1) hydrolyzes L-asparagine in L-aspartic acid and ammonia. Its efficiency is subject to its kinetics and specificity on the substrate, characteristics that vary from one source to another. Thus, microorganisms from saline environments constitute a phylogenetic and metabolically heterogeneous group for the search of new enzymes. Therefore, the objective of this study was the phenotypic and genotypic characterization of bacteria with L-asparaginase activity isolated from Maras, Pilluana and Chilca salterns. The 24 evaluated bacteria were classified as 38% Gram-negative bacilli and 54% positive; and 8% Gram-positive cocci. The majority grew in 5% salt water, pH 7.0 and 37 °C, all assimilated glucose. Of the 24 bacteria that produced L-asparaginase in solid medium, enzymatic activity was determined in submerged cultures by the Nessler method in 14 of them. The CH11,...