Please use this identifier to cite or link to this item: http://scholarbank.nus.edu.sg/handle/10635/100250
Title: Characterization of the Pac25I restriction-modification genes isolated from the endogenous pRA2 plasmid of Pseudomonas alcaligenes NCIB 9867
Authors: Yeo, C.C.
Tham, J.M. 
Kwong, S.M.
Poh, C.L.
Issue Date: Nov-1998
Citation: Yeo, C.C., Tham, J.M., Kwong, S.M., Poh, C.L. (1998-11). Characterization of the Pac25I restriction-modification genes isolated from the endogenous pRA2 plasmid of Pseudomonas alcaligenes NCIB 9867. Plasmid 40 (3) : 203-213. ScholarBank@NUS Repository.
Abstract: Genes for the class II Pseudomonas alcaligenes NCIB 9867 restriction- modification (R-M) system, Pac25I, have been cloned from its 33-kb endogenous plasmid, pRA2. The Pac25I endonuclease and methylase genes were found to be aligned in a head-to-tail orientation with the methylase gene preceding and overlapping the endonuclease gene by 1 bp. The deduced amino acid sequence of the Pac25I methylase revealed significant similarity with the XcyI, XmaI, Cfr9I, and SmaI methylases. High sequence similarity was displayed between the Pac25I endonuclease and the XcyI, XmaI, and Cfr9I endonucleases which cleave between the external cytosines of the recognition sequence (i.e., 5'- C↓CCGGG-3') and are thus perfect isoschizomers. However, no sequence similarity was detected between the Pac25I endonuclease and the SmaI endonuclease which cleaves between the internal CpG of the recognition sequence (i.e., 5'-CCC↓GGG-3'). Both the Pac25I methylase and endonuclease were expressed in Escherichia coli. An open reading frame encoding a protein which shows significant similarity to invertases and resolvases was located immediately upstream of the Pac25I R-M operon. In addition, a transposon designated Tn5563 was located 1531 bp downstream of the R-M genes. The location on a self-transmissible plasmid as well as the close association with genes involved in DNA mobility suggests horizontal transfer as a possible mode of distribution of this family of R-M genes in various bacteria.
Source Title: Plasmid
URI: http://scholarbank.nus.edu.sg/handle/10635/100250
ISSN: 0147619X
Appears in Collections:Staff Publications

Show full item record
Files in This Item:
There are no files associated with this item.

SCOPUSTM   
Citations

3
checked on Feb 27, 2018

WEB OF SCIENCETM
Citations

3
checked on May 1, 2018

Page view(s)

27
checked on Jun 8, 2018

Google ScholarTM

Check


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.