Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P43026 (lipopolysaccharide)
 62,215 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We examined the resistance of Neisseria gonorrhoeae to proteins prepared from the granules of human polymorphonuclear neutrophils (PMNs). We found that nearly isogenic strains differing in lipopolysaccharide subunit molecular weight also differed in levels of resistance to crude granule extracts. N. gonorrhoeae strain WS1 was at least 10-fold less resistant than the parental strain FA 102 to granule extracts. Surprisingly, strain WS1 did not differ from FA 102 in resistance to two isolated antimicrobial proteins obtained previously from extracts of human PMN granules. We used strain WS1 in assays that detected antimicrobial proteins in granule extracts, and we obtained at least two proteins with apparent molecular masses of 24-25.5 kilodaltons that exerted potent in vitro antigonococcal activity. We found that the ED50 (concentration of protein required to kill 50% of gonococci) against the strain WS1 was approximately 0.006 microgram of protein/ml, whereas the ED50 against the parental strain (FA 102) was approximately 0.4 microgram of protein/ml. Accordingly, alterations in lipopolysaccharide structure apparently caused a 66-fold decrease in gonococcal resistance to granule proteins. Our data suggest that gonococcal resistance to oxygen-independent antimicrobial systems of human PMNs may, in part, depend on the availability of certain lipopolysaccharide domains involved in recognition of the antimicrobial granule proteins described in this report.
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PMID:A spontaneous mutant of Neisseria gonorrhoeae with decreased resistance to neutrophil granule proteins. 308 66

Neisseria gonorrhoeae WS1 is a spontaneous pyocin (a bacteriocin produced by Pseudomonas aeruginosa)-resistant mutant of N. gonorrhoeae FA19 that produces a truncated lipooligosaccharide (LOS) and is non-transformable. The LOS-specific mutation in WS1 was moved into a transformable background by transforming FA19 with chromosomal DNA from WS1 (generating strain JWS-1). A clone (pJCL2) capable of restoring JWS-1 to wild-type LOS expression, as detected by its acquisition of reactivity with monoclonal antibodies and by its complemented sodium dodecyl sulfate-polyacrylamide gel electrophoresis profile, was isolated. Sequential unidirectional deletion and DNA sequence analysis of pJCL2 identified an open reading frame, designated lsi-7, that could complement the defect in JWS-1. Homology searches against various databases indicated that lsi-7 bad homology with several Escherichia coli genes involved in the phosphorylation of sugars. lsi-7 is adjacent to the lsi-6 gene, another gene involved in LOS biosynthesis. Complementation studies using Salmonella typhimurium lipopolysaccharide mutants showed lsi-6 and lsi-7 to be gonococcal homologs of S. typhimurium rfaD and rfaE, respectively. Reverse transcriptase PCR analysis demonstrated that lsi-6 and lsi-7 are part of the same transcriptional unit.
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PMID:Cloning, complementation, and characterization of an rfaE homolog from Neisseria gonorrhoeae. 875 86