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)

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
1,2	LIP
1,3	bDGalp	104.45	71.66	73.86	69.17	75.50	61.83
1	x?Gro	63.17	70.80	68.38
	LIP


1H NMR data:
Linkage	Residue	H1	H2	H3	H4	H5	H6
1,2	LIP
1,3	bDGalp	4.24	3.55	3.50	3.89	3.51	3.76-3.82
1	x?Gro	4.23-4.39	5.28	3.73-3.96
	LIP


1H/13C HSQC data:
Linkage	Residue	C1/H1	C2/H2	C3/H3	C4/H4	C5/H5	C6/H6
1,2	LIP
1,3	bDGalp	104.45/4.24	71.66/3.55	73.86/3.50	69.17/3.89	75.50/3.51	61.83/3.76-3.82
1	x?Gro	63.17/4.23-4.39	70.80/5.28	68.38/3.73-3.96
	LIP

There is only one chemically distinct structure:

SVGMWSMILES3D molIonize

 

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

252.219 g/mol (C₉H₁₆R₂O₈, R = residue superclass(es), not counted in mol weight)

The chemical structure of the major glycolipid present in the chloroform-methanol extract of bacterial biomass of Tsukamurella pulmonis is reported. This compound was purified by TLC and HPLC. The sugar analysis revealed only glucose. Detailed chemical analyses, NMR, and MALDI FT-ICR-mass spectrometric studies identified 2,3-di-O-acyl-α-D-glucopyranosyl-(1→1)-α-D-glucopyranose as the final structure. Short branched fatty acids (4:0 or 5:0) were linked to C-3 and saturated, mono, and diunsaturated 18:0, 18:1, 18:2, 20:1, 20:2, and 20:0 to C-2 of the same glucose residue. ELISA tests revealed the weak cross-reactivity of the glycolipid with rabbit antisera against cells of T. paurometabola, Rhodococcus wratislaviensis, and Nocardiopsis dassonvillei.

glycolipid, Diacyltrehalose, Tsukamurella pulmonis

13C NMR data:
Linkage	Residue	C1	C2	C3	C4	C5	C6
1	aDGlcp	91.53	70.64	71.97	68.79	73.32	61.11
	aDGlcp	94.37	71.52	73.17	70.04	72.43	61.11
1,2	LIP
1,2	lXAch
1,2	lXC18={?}
1,2	lXSte
1,3	lXiBut
1,3	lXiVl


1H NMR data:
Linkage	Residue	H1	H2	H3	H4	H5	H6
1	aDGlcp	5.269	4.867	5.443	3.547	3.941	3.702-3.838
	aDGlcp	5.083	3.516	3.772	3.402	3.581	3.695
1,2	LIP
1,2	lXAch
1,2	lXC18={?}
1,2	lXSte
1,3	lXiBut
1,3	lXiVl


1H/13C HSQC data:
Linkage	Residue	C1/H1	C2/H2	C3/H3	C4/H4	C5/H5	C6/H6
1	aDGlcp	91.53/5.269	70.64/4.867	71.97/5.443	68.79/3.547	73.32/3.941	61.11/3.702-3.838
	aDGlcp	94.37/5.083	71.52/3.516	73.17/3.772	70.04/3.402	72.43/3.581	61.11/3.695
1,2	LIP
1,2	lXAch
1,2	lXC18={?}
1,2	lXSte
1,3	lXiBut
1,3	lXiVl

There is only one chemically distinct structure:

SVGMWSMILES3D molIonize

 

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

411.38 g/mol (C₁₆H₂₇RO₁₂, R = residue superclass(es), not counted in mol weight)