Aminotransferase and glutamate dehydrogenase activities in lactobacilli and streptococci.
Aminotransferases and glutamate dehydrogenase are two main types of enzymes involved in the initial steps of amino acid catabolism, which plays a key role in the cheese flavor development. In the present work, glutamate dehydrogenase and aminotransferase activities were screened in twenty one strains of lactic acid bacteria of dairy interest, either cheese-isolated or commercial starters, including fifteen mesophilic lactobacilli, four thermophilic lactobacilli, and two streptococci. The strains of Streptococcus thermophilus showed the highest glutamate dehydrogenase activity, which was significantly elevated compared with the lactobacilli. Aspartate aminotransferase prevailed in most strains tested, while the levels and specificity of other aminotransferases were highly strain- and species-dependent. The knowledge of enzymatic profiles of these starter and cheese-isolated cultures is helpful in proposing appropriate combinations of strains for improved or increased cheese flavor.
Institute of Industrial Lactology, National University of Litoral, National Council of Scientific and Technique Research (INLAIN-UNL/CONICET), Santiago del Estero, Santa Fe, Argentina.
Guillermo Hugo
GH
Peralta
Institute of Industrial Lactology, National University of Litoral, National Council of Scientific and Technique Research (INLAIN-UNL/CONICET), Santiago del Estero, Santa Fe, Argentina; Faculty of Chemical Engineering, National University of Litoral (FIQ-UNL), Santiago del Estero, Santa Fe, Argentina. Electronic address: bergaminicarina@gmail.com.
Carina Viviana
CV
Bergamini
Institute of Industrial Lactology, National University of Litoral, National Council of Scientific and Technique Research (INLAIN-UNL/CONICET), Santiago del Estero, Santa Fe, Argentina; Faculty of Chemical Engineering, National University of Litoral (FIQ-UNL), Santiago del Estero, Santa Fe, Argentina.
Erica Rut
ER
Hynes
D002474:Cell-Free System; D004789:Enzyme Activation; D005516:Food Microbiology; D005969:Glutamate Dehydrogenase / Q000378:metabolism*; D006801:Humans; D007778:Lactobacillus / Q000201:enzymology*; D013291:Streptococcus / Q000201:enzymology*; D000637:Transaminases / Q000378:metabolism*
D005969:Glutamate Dehydrogenase; D000637:Transaminases
Aminotransferase activity; Glutamate dehydrogenase activity; Lactobacilli; Streptococci