A Multicomponent System Is Required for Tetracycline-Induced Excision of Tn4555
Author
Parker, Anita C.; Smith, C. Jeffrey
Abstract
Bacteroides spp. are the predominant organisms in the intestinal tract, and they also are important opportunistic
pathogens. Antibiotic therapy of Bacteroides infections often is complicated by the prevalence of
drug-resistant organisms which acquire resistance genes from a variety of mobile genetic elements including
conjugative transposons (CTns) and mobilizable transposons (MTns). Tn4555 is an MTn that encodes
-lactam resistance, and it is efficiently mobilized by the Bacteroides CTns via a tetracycline (TET)-inducible
mechanism. In this study a model system with CTn341 and a Tn4555 minielement was used to examine Tn4555
excision from the chromosome. Using PCR and mobilization assays it was established that excision was
stimulated by TET in the presence of CTn341. In order to determine which Tn4555 genes were required for
excision, int, tnpA, tnpC, xis, and mobA mutants were examined. The results indicated that int plus two
additional genes, tnpC and xis, were required for optimal excision. In addition, there was no requirement for
the mobA gene, as had been shown for another MTn, NBU1. The Xis protein sequence is related to a family of
plasmid excisionases, but the TnpC gene product did not match anything in the sequence databases. Evidence
also was obtained that suggested that Xis is involved in the control of TET-induced excision and in control of
mobilization by CTn341. Overall, these results indicate that excision of MTns is a complex process that
requires multiple gene products. Originally published Journal of Bacteriology, Vol. 186, No. 2, Jan. 2004
Subject
Date
2004-01
Citation:
APA:
Parker, Anita C., & Smith, C. Jeffrey. (January 2004).
A Multicomponent System Is Required for Tetracycline-Induced Excision of Tn4555.
Journal of Bacteriology,
186(2),
438-
444. Retrieved from
http://hdl.handle.net/10342/3045
MLA:
Parker, Anita C., and Smith, C. Jeffrey.
"A Multicomponent System Is Required for Tetracycline-Induced Excision of Tn4555". Journal of Bacteriology.
186:2. (438-444),
January 2004.
December 11, 2023.
http://hdl.handle.net/10342/3045.
Chicago:
Parker, Anita C. and Smith, C. Jeffrey,
"A Multicomponent System Is Required for Tetracycline-Induced Excision of Tn4555," Journal of Bacteriology 186, no.
2 (January 2004),
http://hdl.handle.net/10342/3045 (accessed
December 11, 2023).
AMA:
Parker, Anita C., Smith, C. Jeffrey.
A Multicomponent System Is Required for Tetracycline-Induced Excision of Tn4555. Journal of Bacteriology.
January 2004;
186(2):
438-444.
http://hdl.handle.net/10342/3045. Accessed
December 11, 2023.
Collections
Publisher
East Carolina University