This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Dorward, D W Articles by Garon, C F Search for Related Content PubMed PubMed Citation Articles by Dorward, D W Articles by Garon, C F

research-article

DNA-binding proteins in cells and membrane blebs of Neisseria gonorrhoeae.

Laboratory of Pathobiology, National Institute of Allergy and Infectious Diseases, Rocky Mountain Laboratories, Hamilton, Montana 59840.

ABSTRACT

Naturally elaborated membrane bleb fractions BI and BII of Neisseria gonorrhoeae contain both linear and circular DNAs. Because little is known about the interactions between DNA and blebs, studies were initiated to identify specific proteins that bind DNA in elaborated membrane blebs. Western immunoblots of whole-cell and bleb proteins from transformation-competent and DNA-uptake-deficient (dud) mutants were probed with single- or double-stranded gonococcal DNA, pBR322, or synthetic DNA oligomers containing intact or altered gonococcal transformation uptake sequences. The specificity and sensitivity of a nonradioactive DNA-binding protein assay was evaluated, and the assay was used to visualize DNA-protein complexes on the blots. The complexes were then characterized by molecular mass, DNA-binding specificity, and expression in bleb fractions. The assay effectively detected blotted DNA-binding proteins. At least 17 gonococcal DNA-binding proteins were identified; unique subsets occurred in BI and BII. Certain DNA-binding proteins had varied affinities for single- and double-stranded DNA, and the intact transformation uptake sequence competitively displaced the altered sequence from a BI protein at 11 kilodaltons (kDa). A dud mutant, strain FA660, lacked DNA-binding activity at the 11-kDa protein in BI. The segregation of DNA-binding proteins within BI and BII correlates with their distinct protein profiles and suggests that these vesicles may play different roles. Although the DNA-binding proteins expressed in BII may influence the nuclease-resistant export of plasmids within BII vesicles, the BI 11-kDa protein may bind transforming DNA.

This article has been cited by other articles:

• Kuehn, M. J., Kesty, N. C. (2005). Bacterial outer membrane vesicles and the host-pathogen interaction. Genes Dev. 19: 2645-2655 [Abstract] [Full Text]  
• van Schaik, E. J., Giltner, C. L., Audette, G. F., Keizer, D. W., Bautista, D. L., Slupsky, C. M., Sykes, B. D., Irvin, R. T. (2005). DNA Binding: a Novel Function of Pseudomonas aeruginosa Type IV Pili. J. Bacteriol. 187: 1455-1464 [Abstract] [Full Text]  
• Renelli, M., Matias, V., Lo, R. Y., Beveridge, T. J. (2004). DNA-containing membrane vesicles of Pseudomonas aeruginosa PAO1 and their genetic transformation potential. Microbiology 150: 2161-2169 [Abstract] [Full Text]  
• Yaron, S., Kolling, G. L., Simon, L., Matthews, K. R. (2000). Vesicle-Mediated Transfer of Virulence Genes from Escherichia coli O157:H7 to Other Enteric Bacteria. Appl. Environ. Microbiol. 66: 4414-4420 [Abstract] [Full Text]  
• Petersson, C., Larsson, B., Mahdavi, J., Borén, T., Magnusson, K.-E. (2000). A New Method to Visualize the Helicobacter pylori-associated Lewisb-binding Adhesin Utilizing SDS-digested Freeze-fracture Replica Labeling. J. Histochem. Cytochem. 48: 877-884 [Abstract] [Full Text]  
• Horstman, A. L., Kuehn, M. J. (2000). Enterotoxigenic Escherichia coli Secretes Active Heat-labile Enterotoxin via Outer Membrane Vesicles. J. Biol. Chem. 275: 12489-12496 [Abstract] [Full Text]