Novel fermentation products from Streptomyces fradiae: X-ray crystal structure of 5-O-mycarosyltylactone and proof of the absolute configuration of tylosin.
5-O-Mycarosyltylactone has been isolated as a predominant factor from fermentation broths of a Streptomyces fradiae mutant. The relative configurations of mycarose and tylactone (protylonolide) have been determined by X-ray crystal structure analysis. Hydrolysis of 5-O-mycarosyltylactone yielded (-)-tylactone and L-(-)-mycarose. Taken together, these two experiments establish the absolute configuration of (-)-tylactone. Bioconversion of (-)-tylactone to tylosin by tyl G mutants of S. fradiae proves the absolute configuration of tylosin. Physicochemical data for tylactone and a unique component piece of tylactone are also reported.
D000080890:Duocarmycins; D005285:Fermentation; D007211:Indoles; D007933:Leucomycins; D008968:Molecular Conformation; D013302:Streptomyces / Q000378:metabolism*; D014961:X-Ray Diffraction
D000080890:Duocarmycins; D007211:Indoles; D007933:Leucomycins; C018782:CC 1065