Analysis of proteins associated with growth of Bacteroides ovatus on the branched galactomannan guar gum.

摘要: Bacteroides ovatus, a gram-negative obligate anaerobe from the human colon, can ferment branched galactomannan guar gum. Previously, three enzymes involved in gum breakdown were characterized. The expression of these appeared to be regulated; i.e., specific activities higher extracts bacteria grown on than monosaccharide constituents gum, mannose and galactose. In present study, we used two-dimensional gel analysis determine total number B. ovatus proteins enhanced during growth Twelve soluble 20 membrane expressed at levels gum-grown cells galactose-grown cells. An unexpected finding was that two galactomannanases induced by glucose as well Three other proteins, one protein had this same pattern. remainder gum-associated seen gels alpha-galactosidase but not glucose. Two transposon-generated mutants (M-5 M-7) could grow isolated. Both still alpha-galactosidase. They also all detected glucose-grown or A second transposon insertion suppressed gum-negative phenotype M-5 isolated characteristics suppressor mutant indicated original probably regulatory locus.