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Genetic and chemical characterization of a mutant that disrupts synthesis of the lipopolysaccharide core tetrasaccharide in Rhizobium leguminosarum.

ABSTRACT: A 2-kb region that complements the Tn5-derived lipopolysaccharide (LPS) rough mutant Rhizobium leguminosarum RU301 was sequenced. Two open reading frames (ORFs) were identified. The first ORF (lpcA) is homologous to a family of bacterial sugar transferases involved in LPS core tetrasaccharide biosynthesis. ORF2 (lpcB), in which Tn5 transposed, has no significant homology to any DNA in the GenBank-EMBL databases. Chemical characterization of LPS produced by strain RU301 demonstrated that the 3-deoxy-D-manno-2-octulosonic acid (Kdo) residue which normally attaches the core tetrasaccharide to the O chain was missing, suggesting that IpcB may encode a CMP-Kdo:LPS Kdo transferase.

SUBMITTER: Allaway D

PROVIDER: S-EPMC178523 | biostudies-other | 1996 Nov

REPOSITORIES: biostudies-other

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Genetic and chemical characterization of a mutant that disrupts synthesis of the lipopolysaccharide core tetrasaccharide in Rhizobium leguminosarum.

Allaway D D Jeyaretnam B B Carlson R W RW Poole P S PS

Journal of bacteriology 19961101 21

A 2-kb region that complements the Tn5-derived lipopolysaccharide (LPS) rough mutant Rhizobium leguminosarum RU301 was sequenced. Two open reading frames (ORFs) were identified. The first ORF (lpcA) is homologous to a family of bacterial sugar transferases involved in LPS core tetrasaccharide biosynthesis. ORF2 (lpcB), in which Tn5 transposed, has no significant homology to any DNA in the GenBank-EMBL databases. Chemical characterization of LPS produced by strain RU301 demonstrated that the 3-de ...[more]

PMID: 8892852

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