Utilization of cellobiose and other beta-D-glucosides in Agrobacterium tumefaciens.

Agrobacterium tumefaciens strain C58 was able to utilize carbon from cellobiose and some other beta-D-glucosides as efficiently as from glucose. beta-D-glucoside utilization was partially inducible and the induction was subject to catabolite repression by glucose, independently of the presence of cyclic AMP in the medium. It was also independent of Ti plasmid-encoded functions. beta-D-glucosides were hydrolysed by a single, cytoplasmic and constitutively expressed beta-glucosidase, which was active on non-phosphorylated substrates and insensitive to glucose inhibition.