The cells that line the mammalian intestine produce glycoproteins with O-linked oligosaccharides. Some of the glycoproteins remain anchored to the cell surface and some are released into the intestinal space. In a healthy animal, numerous microbial species (the microbiome) live in the intestine. These organisms produce fucosidase, an enzyme that hydrolyzes glycosidic bonds involving fucose.

(a) Why is this enzyme useful to the microorganisms?

(b) Pathogenic (disease-causing) bacteria typically lack fucosidase. How does this help prevent the growth of pathogens in the intestine, particularly during an illness when the human host stops eating?