Background: Fructooligosaccharides (FOS) have been identified as important prebiotics. Previous studies have found that they can significantly promote the proliferation of Bifidobacterium pseudolongum in the mouse intestine. However, it is still unclear which other bacteria in the mouse intestine can utilize FOS, and the differences in the ability to utilize FOS. In this study, the bacteria capable of utilizing FOS were isolated from mice feces and their ability to utilize FOS was compared. Draft genome sequencing was also applied to explain the differences in FOS utilization at the gene levels.
Results: A total of 15 species were isolated from mouse feces and 13 species were able to utilize fructofuranosylnystose (GF2). Eleven species could utilize nistose (GF3), but not Enterococcus hirae and Lactobacillus reuteri. In contrast, 1-kestose (GF4) was hardly utilized. The enzyme activity determination and draft genome sequencing-based analyses revealed that all isolated species used the phosphotransferase system or permease system to transport FOS into the cells before hydrolysis by β-fructofuranosidase. Although β-fructofuranosidase exists in all strains, there are big differences in the corresponding coding genes between bifidobacteria and non-bifidobacteria.
Conclusion: Compared with the other isolates, Bifidobacterium species exhibited higher enzyme activity and shorter generation time, leading to a stronger ability to utilize FOS. © 2021 Society of Chemical Industry.
Keywords: Bifidobacterium; FOS; draft genome sequencing; transport system; β-fructofuranosidase.
© 2021 Society of Chemical Industry.