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Genetic basis of Neisseria gonorrhoeae lipooligosaccharide antigenic variation.

ABSTRACT: Neisseria gonorrhoeae lipooligosaccharide (LOS) undergoes antigenic variation at a high rate, and this variation can be monitored by changes in a strain's ability to bind LOS-specific monoclonal antibodies. We report here the cloning and identification of a gene, lsi-2, that can mediate this variation. The DNA sequence of lsi-2 has been determined for N. gonorrhoeae 1291, a strain that expresses a high-molecular-mass LOS, and a derivative of this strain, RS132L, that produces a truncated LOS. In the parental strain, lsi-2 contains a string of 12 guanines in the middle of its coding sequence. In cells that had antigenically varied to produce a truncated LOS, the number of guanines in lsi-2 was altered. Site-specific deletions were constructed to verify that expression of a 3.6-kDa LOS is due to alterations in lsi-2.

SUBMITTER: Danaher RJ

PROVIDER: S-EPMC177611 | biostudies-other | 1995 Dec

REPOSITORIES: biostudies-other

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Genetic basis of Neisseria gonorrhoeae lipooligosaccharide antigenic variation.

Danaher R J RJ Levin J C JC Arking D D Burch C L CL Sandlin R R Stein D C DC

Journal of bacteriology 19951201 24

Neisseria gonorrhoeae lipooligosaccharide (LOS) undergoes antigenic variation at a high rate, and this variation can be monitored by changes in a strain's ability to bind LOS-specific monoclonal antibodies. We report here the cloning and identification of a gene, lsi-2, that can mediate this variation. The DNA sequence of lsi-2 has been determined for N. gonorrhoeae 1291, a strain that expresses a high-molecular-mass LOS, and a derivative of this strain, RS132L, that produces a truncated LOS. In ...[more]

PMID: 8522539

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Antigenic variation in Neisseria gonorrhoeae: production of multiple lipooligosaccharides.

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