Effect of growth temperature on the biosynthesis of cell wall proteins from Bifidobacterium globosum.

Seventy strains of Bifidobacterium globosum isolated from gastrointestinal tracts of different animals were studied. Strains were grown at temperatures ranging from 25 to 46.5 degrees C in order to examine changes both in the expression of bifidobacterial outer proteins (BIFOPs) and in their hydrophobic properties.

Bifidobacterium inopinatum sp. nov. and Bifidobacterium denticolens sp. nov., two new species isolated from human dental caries.

In a previous investigation of bifidobacteria isolated from human dental caries (V. Scardovi and F. Crociani, Int.

Degradation of complex carbohydrates by Bifidobacterium spp.

Two hundred and ninety strains of 29 species of bifidobacteria from human and animal origin were surveyed for their ability to ferment complex carbohydrates. The substrates fermented by the largest number of species were D-galactosamine, D-glucosamine, amylose and amylopectin. Many of the species isolated from animal habitats showed reduced fermentation activity.

Characterization of the plasmid pVS809 from Bifidobacterium globosum.

A plasmid from a B. globosum strain was cut with 38 restriction enzymes and a physical map was constructed. Out of a total of 121 clones from curing experiments, plasmid was lost in 58% and 100% for acridine orange and ethidium bromide curing agent respectively.

Regulation of dihydrodipicolinate synthase and diaminopimelate decarboxylase activity in Bacillus stearothermophilus.

The feedback inhibition of the enzymes dihydrodipicolinate (DHDPS) and diaminopimelate decarboxylase (DAPD) in the wild strain Zu 183 of Bacillus stearothermophilus and in its S-(2-aminoethyl)-cysteine resistant L-lysine overproducing strain AEC 12 was studied. The optimum temperature and pH of both enzymes were also evaluated. No inhibition of DHDPS by L-lysine, L-threonine, L-methionine and L-isoleucine was observed either in the wild strain or in the AEC 12 mutant.