On the localization of xylanolytic enzymes in Prevotella Bryantii B14

Abstract

Prevotella bryantii B₁4 is a strictly anaerobic, Gram-negative, polysaccharides-degrading ruminal bacterium. EDTA/sphaeroplasting and osmotic shock procedure were used in present work to localise endoxylanolytic, b -xylosidase and a -L-arabinofuranosidase activities of P. bryantii B₁4. Late exponential phase cells released most of the endoxylanolytic and CMC-ase activity by osmotic shock, showing the periplasmic location of both enzymatic activities, while b -xylosidase and a -L-arabinofuranosidase activities were recovered largely in membrane cell fraction. About 23 % of the total culture endoxylanase activity and about 30 % of the CMC-ase activity were found to be extracellular. No b -xylosidase and a -L-arabinofuranosidase activities were detected in culture supernatant of P. bryantii B₁4.