Cloning, complementation, and characterization of an rfaE homolog from Neisseria gonorrhoeae.

AUTOR(ES)

Levin, J C

RESUMO

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.

Documentos Relacionados

• Identification and cloning of a fur homolog from Neisseria gonorrhoeae.
• Molecular cloning and characterization of the nontypeable Haemophilus influenzae 2019 rfaE gene required for lipopolysaccharide biosynthesis.
• Purification and characterization of DNA methyltransferases from Neisseria gonorrhoeae.
• Cloning, sequencing, and characterization of the gene encoding FrpB, a major iron-regulated, outer membrane protein of Neisseria gonorrhoeae.
• Cloning and organization of seven arginine biosynthesis genes from Neisseria gonorrhoeae.