Substrate flexibility of a 2,6-dideoxyglycosyltransferase

Area of Science:

• Biochemistry
• Synthetic Biology
• Carbohydrate Chemistry

Background:

• Biosynthetic gene clusters are crucial for producing complex natural products, including deoxy sugars.
• Understanding the enzymatic machinery involved in deoxy sugar biosynthesis is essential for metabolic engineering.

Purpose of the Study:

• To characterize a novel 2,6-dideoxysugar-O-glycosyltransferase with flexible substrate specificity.
• To confirm the function of a putative NDP-hexose 2,3-dehydratase within the jadomycin B biosynthetic pathway.
• To elucidate the substrate flexibility of enzymes involved in l-digitoxose assembly.

Main Methods:

• Enzymatic assays to determine substrate specificity of the identified glycosyltransferase.
• Gene knockout and complementation studies to confirm the function of the NDP-hexose 2,3-dehydratase.
• In vitro reconstruction of the l-digitoxose assembly pathway.

Main Results:

• The first 2,6-dideoxysugar-O-glycosyltransferase exhibiting substrate flexibility at the 2-position was identified and characterized.
• The function of the putative NDP-hexose 2,3-dehydratase in the jadomycin B cluster was confirmed.
• Substrate flexibility of downstream enzymes in l-digitoxose assembly was deduced, revealing potential for pathway engineering.

Conclusions:

• The identified glycosyltransferase and characterized dehydratase provide new tools for deoxy sugar biosynthesis.
• Reprogramming of biosynthetic gene clusters can be achieved by understanding and manipulating sugar substituent assembly.
• This work enables the engineering of novel sugar modifications for diverse applications.