Title:Heat-Loving β-Galactosidases from Cultured and Uncultured Microorganisms
VOLUME: 19 ISSUE: 12
Author(s):Maria-Eugenia DeCastro, Juan-Jose Escuder-Rodriguez, Maria-Esperanza Cerdan, Manuel Becerra, Esther Rodriguez-Belmonte and Maria-Isabel Gonzalez-Siso*
Affiliation:Grupo EXPRELA, Centro de Investigacions Científicas Avanzadas (CICA), Departamento de Bioloxia, Facultade de Ciencias, Universidade da Coruna, Campus de A Coruna, 15071 A Coruna, Grupo EXPRELA, Centro de Investigacions Científicas Avanzadas (CICA), Departamento de Bioloxia, Facultade de Ciencias, Universidade da Coruna, Campus de A Coruna, 15071 A Coruna, Grupo EXPRELA, Centro de Investigacions Científicas Avanzadas (CICA), Departamento de Bioloxia, Facultade de Ciencias, Universidade da Coruna, Campus de A Coruna, 15071 A Coruna, Grupo EXPRELA, Centro de Investigacions Científicas Avanzadas (CICA), Departamento de Bioloxia, Facultade de Ciencias, Universidade da Coruna, Campus de A Coruna, 15071 A Coruna, Grupo EXPRELA, Centro de Investigacions Científicas Avanzadas (CICA), Departamento de Bioloxia, Facultade de Ciencias, Universidade da Coruna, Campus de A Coruna, 15071 A Coruna, Grupo EXPRELA, Centro de Investigacions Científicas Avanzadas (CICA), Departamento de Bioloxia, Facultade de Ciencias, Universidade da Coruna, Campus de A Coruna, 15071 A Coruna
Keywords:β-galactosidase, lactase, metagenomics, thermozymes, thermostable, GOS.
Abstract:β-galactosidases (EC.3.2.1.23), which hydrolyze lactose to glucose and galactose, have two
main applications in the food industry: the production of low-lactose milk and dairy goods for lactose
intolerant people, and the generation of galacto-oligosaccharides by transgalactosylation reactions. Due
to their thermostability, β-galactosidases from thermophilic microorganisms are very interesting for industrial
processes, as high temperatures can increase the initial productivity of the enzyme, provide
higher solubility of substrates, and prevent microbial contamination. In the past, it was necessary to cultivate
and grow thermophilic microorganisms to discover novel thermozymes, but the development of
metagenomic techniques has allowed researchers to access the genomic potential of uncultivated microbes
and their enzymes. The present review gives a brief outline of thermophilic β-galactosidases, with
a special focus on those obtained through metagenomics. Additionally, the sequences of β-galactosidases
found in some public metagenomes from hot springs were studied and compared to other known thermostable
β-galactosidases.