Studies on the substrate specificity of a GDP-mannose pyrophosphorylase from Salmonella enterica.

摘要: A series of methoxy and deoxy derivatives mannopyranose-1-phosphate (Manp-1P) were chemically synthesized, their ability to be converted into the corresponding guanosine diphosphate mannopyranose (GDP-Manp) analogues by a pyrophosphorylase (GDP-ManPP) from Salmonella enterica was studied. Evaluation demonstrated that GDP-ManPP is intolerant bulky substituents at C-2, C-3, C-4 positions, in turn suggesting these positions are buried inside enzyme active site. Additionally, both 6-methoxy 6-deoxy Manp-1P good or moderate substrates for GDP-ManPP, thus indicating C-6 hydroxy group substrate not required binding enzyme. When taken consideration with other previously published work, it appears this has potential utility chemoenzymatic synthesis GDP-Manp analogues, which useful probes studying enzymes employ sugar nucleotide as substrate.