A thermostable α-galactosidase from Lactobacillus fermentum CRL722: Genetic characterization and main properties

Authors
Carrera Silva, Eugenio Antonio; Silvestroni, A.; Leblanc, Jean Guy Joseph; Piard, J. C.; Savoy, Graciela; Sesma, Fernando Juan Manuel
Publication Year
2006
Language
English
Format
article
Status
Published version
Description
α-Galactosidase (α-Gal) enzyme, which is encoded by the melA gene hydrolyzes α-1,6 galactoside linkages found in sugars, such as raffinose and stachyose. These α-galacto-oligosaccharides (α-GOS), which are found in large quantities in vegetables, such as soy, can cause gastrointestinal disorders in sensitive individuals because monogastric animals (including humans) do not posses α-Gal in the gut. The use of microbial α-Gal is a promising alternative to eliminate α-GOS in soy-derived products. Using degenerate primers, the melA gene from Lactobacillus (L.) fermentum CRL722 was identified. The complete genomic sequence of melA (2223 bp), and of the genes flanking melA, were obtained using a combination of polymerase chain reaction-based techniques, and showed strong similarities with the α-Gal gene of thermophilic microorganisms. The α-Gal gene from L. fermentum CRL722 was cloned and the protein purified from cell-free extracts of the native and recombinant strains using various techniques (ion exchange chromatography, salt precipitation, sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and ultra-filtration); Its main biochemical properties were determined. The enzyme was active at moderately high temperatures (55°C) and stable at wide ranges of temperatures and pH. The thermostable α-Gal from L. fermentum CRL722 could thus be used for technological applications, such as the removal of α-GOS found in soy products. The complete melA gene could also be inserted in other micro-organisms, that can survive in the harsh conditions of the gut to degrade α-GOS in situ. Both strategies would improve the overall acceptability of soy-derived products by improving their nutritional value. © 2006 Springer Science+Business Media, Inc.
Fil: Carrera Silva, Eugenio Antonio. Universidad Nacional de Córdoba; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucuman. Centro de Referencia Para Lactobacilos; Argentina
Fil: Silvestroni, A.. University of Washington. School of Medicine; Estados Unidos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucuman. Centro de Referencia Para Lactobacilos; Argentina
Fil: Leblanc, Jean Guy Joseph. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucuman. Centro de Referencia Para Lactobacilos; Argentina
Fil: Piard, J. C.. Institut National de la Recherche Agronomique; Francia
Fil: Savoy, Graciela. Universidad Nacional de Tucumán; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucuman. Centro de Referencia Para Lactobacilos; Argentina
Fil: Sesma, Fernando Juan Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucuman. Centro de Referencia Para Lactobacilos; Argentina
Subject
NO CORRESPONDE
Inmunología
Medicina Básica
CIENCIAS MÉDICAS Y DE LA SALUD
Access level
Restricted access
License
https://creativecommons.org/licenses/by-nc-sa/2.5/ar/
Repository
CONICET Digital (CONICET)
Institution
Consejo Nacional de Investigaciones Científicas y Técnicas
OAI Identifier
oai:ri.conicet.gov.ar:11336/36718