Activity staining of GDH showing NADPH-dependent GDH activity on acrylamide gel. l-Glutamate was used as substrate for detection of GDH activity. Lanes: 1, S. suis 1933; 2, S. suis 88-5955; 3, S. suis DH5; 4, S. suis type strain; 5, S. suis 95-13626; 6, S. suis 89-1591; 7, S. suis AAH6; 8, E. coli DH5α(pOT410); and 9, S. suis 1933.