Western blot analysis of total protein extracts of S. thermophilus strains CNRZ302 (wild type), NZ6510 (CcpA−), and NZ6510 plus pNZ6103 grown on glucose (G) or lactose (L). Per sample, 10 μg of total protein was loaded, and CcpA proteins were detected using antibodies raised against B. megaterium CcpA. S. thermophilus CcpA was identified as a stained band of approximately 37 kDa. Next to the CcpA protein, several a-specific bands with a higher molecular weight were detected in every sample.