The bacterium Pantoea ananatis was reported to produce glycolipid biosurfactants of unknown structures. Herein, we present the isolation and structural determination of ananatoside A, the main congener of a new family of 15-membered macrodilactone-containing glucolipids. The structure of ananatoside A was elucidated via chemical degradation and spectroscopic methods including 1D/2D NMR analysis, tandem MS/MS, GC-MS, HR-ESI-TOF-MS, MALDI-TOF-MS, and polarimetry. Computational methods were used to predict the most abundant conformers of ananatoside A.

glycolipid, NMR analysis, Pantoea ananatis, biosurfactant, Macrolactone

13C NMR data:
Linkage	Residue	C1	C2	C3	C4	C5	C6	C7	C8	C9	C10
3,3	bDGlcp	106.22	75.61	78.73	72.79	74.96	65.79
3	lR3HODco	172.13	42.32	78.43	37.33	26.25	29.86-30.10	29.86-30.10	32.35	23.22	14.58
	lR3HODco	170.41	41.43	70.33	35.60	25.94	29.72-29.97	29.72-29.97	32.31	23.22	14.58


1H NMR data:
Linkage	Residue	H1	H2	H3	H4	H5	H6	H7	H8	H9	H10
3,3	bDGlcp	5.11	3.95	4.16	3.83	4.11	4.80-5.02
3	lR3HODco	-	2.72-3.02	4.65	1.49-1.72	1.60	1.13-1.17	1.13-1.17	1.13	1.18	0.82
	lR3HODco	-	2.79-2.86	5.89	1.53-1.60	1.33	1.19-1.23	1.19-1.23	1.18	1.23	0.85


1H/13C HSQC data:
Linkage	Residue	C1/H1	C2/H2	C3/H3	C4/H4	C5/H5	C6/H6	C7/H7	C8/H8	C9/H9	C10/H10
3,3	bDGlcp	106.22/5.11	75.61/3.95	78.73/4.16	72.79/3.83	74.96/4.11	65.79/4.80-5.02
3	lR3HODco		42.32/2.72-3.02	78.43/4.65	37.33/1.49-1.72	26.25/1.60	29.86-30.10/1.13-1.17	29.86-30.10/1.13-1.17	32.35/1.13	23.22/1.18	14.58/0.82
	lR3HODco		41.43/2.79-2.86	70.33/5.89	35.60/1.53-1.60	25.94/1.33	29.72-29.97/1.19-1.23	29.72-29.97/1.19-1.23	32.31/1.18	23.22/1.23	14.58/0.85

There is only one chemically distinct structure:

SVGMWSMILES3D molIonize

 

[*]OC[C@H]1O[C@@H](O[C@H](CCCCCCC)CC(=O)O[C@H](CCCCCCC)CC([*])=O)[C@H](O)[C@@H](O)[C@@H]1O

502.645 g/mol (C₂₆H₄₆R₂O₉, R = next and previous repeats, not counted in mol weight)

The bacterium Pantoea ananatis was reported to produce glycolipid biosurfactants of unknown structures. Herein, we present the isolation and structural determination of ananatoside A, the main congener of a new family of 15-membered macrodilactone-containing glucolipids. The structure of ananatoside A was elucidated via chemical degradation and spectroscopic methods including 1D/2D NMR analysis, tandem MS/MS, GC-MS, HR-ESI-TOF-MS, MALDI-TOF-MS, and polarimetry. Computational methods were used to predict the most abundant conformers of ananatoside A.

glycolipid, NMR analysis, Pantoea ananatis, biosurfactant, Macrolactone

There is only one chemically distinct structure:

SVGMWSMILES3D molIonize

 

CCCCCCCC(CC(=O)O)OC(=O)CC(CCCCCCC)O[C@@H]1O[C@H](CO)[C@@H](O)[C@H](O)[C@H]1O

520.66 g/mol (C₂₆H₄₈O₁₀)