Arthrobacter is a genus of Gram-positive bacteria widely distributed in soil. The ability to catabolize a variety of xenobiotics has shown their potential as a detoxifying agent. Recently, Arthrobacter has been also recognized as an opportunistic pathogen. Glycolipids from A. scleromae, a clinical isolate, and A. globiformis, from soil, were isolated by chloroform-methanol extraction and subsequently purified using column chromatography and high-performance liquid chromatography. Structural studies were carried out utilizing specific chemical degradation, matrix-assisted laser-desorption/ionization Fourier transform ion cyclotron resonance mass spectrometry (MALDI FT ICR-MS), and 1D and 2D nuclear magnetic resonance (NMR) spectroscopy. The major glycolipids in A. scleromae and A. globiformis were found to be a diglycosylglycerol with the structure α-Manp-(1→3)-α-Manp-(1→3)-Gro (Man A-Man B-Gro; G1), and a monoglycosylglycerol with the structure β-Galp-(1→3)-Gro (G2). Glycolipids were acylated at positions 1 of Gro and 6 of Man B in the case of G1 and at positions 1 and 2 of Gro in the case of G2. The distribution of the fatty acids was different in both species. A. scleromae glycolipids contained heptadecanoic acid while in the A. globiformis glycolipids mainly pentadecanoic acid could be detected. The substitution by hexadecanoic acid was proportionally similar in both species. The taxonomical value of major glycolipids from Arthrobacter is also presented.

NMR, structure, glycolipid, Arthrobacter, MALDI FT ICR-MS

13C NMR data:
Linkage	Residue	C1	C2	C3	C4	C5	C6
1,3,3	aDManp	101.86	70.32	70.83	67.55	73.08	61.57
1,3,6	LIP
1,3	aDManp	100.55	69.41	78.48	65.99	70.62	63.55
1	x?Gro	64.89	68.04	68.79
	LIP


1H NMR data:
Linkage	Residue	H1	H2	H3	H4	H5	H6
1,3,3	aDManp	5.08	3.96	3.78	3.60	3.75	3.71-3.87
1,3,6	LIP
1,3	aDManp	4.76	4.06	3.83	3.76	3.76	4.29-4.38
1	x?Gro	4.09-4.13	3.98	3.44-3.76
	LIP


1H/13C HSQC data:
Linkage	Residue	C1/H1	C2/H2	C3/H3	C4/H4	C5/H5	C6/H6
1,3,3	aDManp	101.86/5.08	70.32/3.96	70.83/3.78	67.55/3.60	73.08/3.75	61.57/3.71-3.87
1,3,6	LIP
1,3	aDManp	100.55/4.76	69.41/4.06	78.48/3.83	65.99/3.76	70.62/3.76	63.55/4.29-4.38
1	x?Gro	64.89/4.09-4.13	68.04/3.98	68.79/3.44-3.76
	LIP

There is only one chemically distinct structure:

SVGMWSMILES3D molIonize

 

R1 = LIP
[1*]OCC(O)CO[C@H]1O[C@H](CO[1*])[C@@H](O)[C@H](O[C@H]2O[C@H](CO)[C@@H](O)[C@H](O)[C@@H]2O)[C@@H]1O

414.36 g/mol (C₁₅H₂₆R₂O₁₃, R = residue superclass(es), not counted in mol weight)