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Updated: Jun 2, 2026
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Metabolic Glycoengineering of Sialic Acid Using N-acyl-modified Mannosamines
Published on: November 25, 2017
New microbial mannan catabolic pathway that involves a novel mannosylglucose phosphorylase
Takeshi Senoura1, Shigeaki Ito, Hidenori Taguchi
1Creative Research Initiative 'Sousei', Hokkaido University, N-21 W-10 Kita-ku, Sapporo, Japan.
Summary
Researchers identified a novel mannan catabolic pathway in Bacteroides fragilis. This pathway utilizes mannosylglucose phosphorylase and other enzymes to break down mannan, contributing to microbial metabolism.
Area of Science:
- Microbiology
- Biochemistry
- Genomics
Background:
- Mannan is a complex polysaccharide found in microbial cell walls.
- Understanding mannan catabolism is crucial for microbial physiology and biotechnology.
- Bacteroides fragilis is an important anaerobic gut bacterium.
Purpose of the Study:
- To elucidate a novel mannan catabolic pathway in Bacteroides fragilis.
- To characterize the function of the BF0772 gene and its encoded enzyme.
- To identify the genes involved in mannan breakdown and their organization.
Main Methods:
- Genomic analysis of the BF0771-BF0774 gene cluster in Bacteroides fragilis NCTC 9343.
- Functional characterization of the BF0772 gene product.
- Enzymatic assay to determine the catalytic activity of the novel enzyme.
Main Results:
- The genes BF0771-BF0774 form an operon in Bacteroides fragilis.
- The BF0772 gene encodes a novel mannosylglucose phosphorylase.
- A new mannan catabolic pathway involving 1,4-β-mannanase, a sugar transporter, mannobiose 2-epimerase, and mannosylglucose phosphorylase was proposed.
- This pathway leads to glycolysis and is present in various microbes.
Conclusions:
- A novel mannan catabolic pathway has been identified in Bacteroides fragilis.
- Mannosylglucose phosphorylase plays a key role in mannan degradation.
- This pathway contributes to the utilization of complex carbohydrates by anaerobic bacteria.
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