2Laboratory of Animal Cell Biotechnology, Departmrnt of Agricultural Biotechnology, Seoul National University, Building 200-#4204, Sillim-9 dong, Seoul 151-742, Republic of Korea; E-mail: email@example.com
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Received October 30, 2010; Revision received November 19, 2010
Glutathione (GSH) is an abundant nonprotein thiol that plays numerous roles within the cell. Previously, we showed that Lactobacillus salivarius has the capacity to mount a glutathione-mediated acid-tolerance response. In the present work we provide evidence of a requirement for GSH by Lactobacillus reuteri and have studied the role of GSH during cell growth. Medium supplementation with 0.5 mM GSH as the sole sulfur source enhanced cell growth, resulting in an increase in glucose consumption, and increased cell GSH and protein contents compared with levels seen in the absence of supplementation. Moreover, L. reuteri showed enhanced amino acid consumption when grown with 0.5 mM GSH. These findings indicate that glutathione is a nutrient for bacterial growth.
KEY WORDS: amino acid consumption, bacterial growth, glutathione, Lactobacillus reuteri, protein content