Insights into β-manno-oligosaccharide uptake and metabolism in Bifidobacterium adolescentis DSMZ 20083 from whole-genome microarray analysis
AimsTo determine the ability of adult-associated B. adolescentis DSMZ 20083 to utilize dietary {beta}-manno-oligosaccharides and understand the underlying molecular mechanism. Methods and ResultsIn-vitro fermentation and TLC were used to determine the ability of B. adolescentis DSMZ 20083 to utilize {beta}-manno-oligosaccharides from guar gum, locust bean gum, konjac and copra meal. Further, Whole-genome transcriptome analysis, q-RT-PCR and molecular docking were employed to reconstruct copra meal {beta}-manno-oligosaccharides (CM-{beta}-MOS) utilization pathway in B. adolescentis DSMZ 20083. B. adolescentis DSMZ 20083 grew appreciably (A600nm up to 0.8) on all tested {beta}-manno-oligosaccharides but maximally on CM-{beta}-MOS. Transcriptome analysis revealed differential up-regulation of three distinct gene clusters encoding, ABC transporter cassette (ESBPs and permeases), MFS transporter, GH1 {beta}-glucosidase and, GH32 {beta}-fructofuranosidases. ABC and MFS possibly transported majorly DP[≥]2 and DP[≥]3 CM-{beta}-MOS, respectively. Sugar absorption and utilization pathways; ABC transport system, pyruvate metabolism, glycolysis/gluconeogenesis, pentose, and glucouronate inter-conversions were also up-regulated. ConclusionsB. adolescentis DSMZ 20083 possibly utilizes ABC & MFS transporters to internalise and GH1 {beta}-glucosidase, and GH32 {beta}-fructofuranosidase to deconstruct CM-{beta}-MOS. Significance and Impact of the StudyFirst study reporting possible molecular determinants used by B. adolescentis DSMZ 20083 to utilize {beta}-manno-oligosaccharides and thus, can prove resourceful in precision microbiome modulation.