Structure of a Neutral O-Specific Polysaccharide of the Bacterium Providencia alcalifaciens O5

G. V. Zatonsky¹, O. V. Bystrova¹, N. A. Kocharova¹, A. S. Shashkov¹, Yu. A. Knirel^1*, E. V. Kholodkova², and E. S. Stanislavsky²

¹Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Leninskii pr. 47, Moscow, 117913 Russia; fax: (095) 135-5328; E-mail: knirel@ioc.ac.ru

²Mechnikov Central Research Institute for Vaccines and Sera, Ministry of Public Health of the Russian Federation, Pereulok Mechnikova 5a, Moscow, 103064 Russia; fax: (095) 916-2587

^* To whom correspondence should be addressed.

Received September 23, 1998; Revision received February 4, 1999

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A neutral polysaccharide containing D-galactose, 2-acetamido-2-deoxy-D-glucose, and 3-acetamido-3,6-dideoxy-D-glucose (Qui3NAc) in the ratios 2:1:1 was obtained by mild acid degradation of lipopolysaccharide of the bacterium Providencia alcalifaciens O5 followed by gel chromatography and ion-exchange chromatography or treatment with anhydrous hydrogen fluoride. On the basis of full acid hydrolysis, methylation, and ¹H- and ¹³C-NMR spectroscopy, including two-dimensional correlation spectroscopy (COSY), total correlation spectroscopy (TOCSY), H-detected heteronuclear ¹H,¹³C single-quantum coherence (HSQC), and nuclear Overhauser effect spectroscopy (NOESY), the following structure of the linear tetrasaccharide repeating unit of the polysaccharide was established:

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KEY WORDS: O-antigen, bacterial polysaccharide, 3-acetamido-3,6-dideoxy-D-glucose, Providencia alcalifaciens

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