A Novel IS Element, IS 621 , of the IS 110 /IS 492 Family Transposes to a Specific Site in Repetitive Extragenic Palindromic Sequences in Escherichia coli

Author:

Choi Sunju1,Ohta Shinya1,Ohtsubo Eiichi1

Affiliation:

1. Institute of Molecular and Cellular Biosciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-0032, Japan

Abstract

ABSTRACT An Escherichia coli strain, ECOR28, was found to have insertions of an identical sequence (1,279 bp in length) at 10 loci in its genome. This insertion sequence (named IS 621 ) has one large open reading frame encoding a putative protein that is 326 amino acids in length. A computer-aided homology search using the DNA sequence as the query revealed that IS 621 was homologous to the piv genes, encoding pilin gene invertase (PIV). A homology search using the amino acid sequence of the putative protein encoded by IS 621 as the query revealed that the protein also has partial homology to transposases encoded by the IS 110 /IS 492 family elements, which were known to have partial homology to PIV. This indicates that IS 621 belongs to the IS 110 /IS 492 family but is most closely related to the piv genes. In fact, a phylogenetic tree constructed on the basis of amino acid sequences of PIV proteins and transposases revealed that IS 621 belongs to the piv gene group, which is distinct from the IS 110 /IS 492 family elements, which form several groups. PIV proteins and transposases encoded by the IS 110 /IS 492 family elements, including IS 621 , have four acidic amino acid residues, which are conserved at positions in their N-terminal regions. These residues may constitute a tetrad D-E(or D)-D-D motif as the catalytic center. Interestingly, IS 621 was inserted at specific sites within repetitive extragenic palindromic (REP) sequences at 10 loci in the ECOR28 genome. IS 621 may not recognize the entire REP sequence in transposition, but it recognizes a 15-bp sequence conserved in the REP sequences around the target site. There are several elements belonging to the IS 110 /IS 492 family that also transpose to specific sites in the repeated sequences, as does IS 621 . IS 621 does not have terminal inverted repeats like most of the IS 110 /IS 492 family elements. The terminal sequences of IS 621 have homology with the 26-bp inverted repeat sequences of pilin gene inversion sites that are recognized and used for inversion of pilin genes by PIV. This suggests that IS 621 initiates transposition through recognition of their terminal regions and cleavage at the ends by a mechanism similar to that used for PIV to promote inversion at the pilin gene inversion sites.

Publisher

American Society for Microbiology

Subject

Molecular Biology,Microbiology

Reference52 articles.

1. Gapped BLAST and PSI-BLAST: a new generation of protein database search programs

2. Ariyoshi, M., D. G. Vassylyev, H. Iwasaki, H. Nakamura, H. Shinagawa, and K. Morikawa. 1994. Atomic structure of the RuvC resolvase: a Holliday junction-specific endonuclease from E. coli.Cell78:1063-1072.

3. Ashby, M. K., and P. L. Bergquist. 1990. Cloning and sequence of IS1000, a putative insertion sequence from Thermus thermophilus HB8. Plasmid24:1-11.

4. Ausubel F. M. R. Brent R. E. Kingston D. D. Moore J. G. Seidman J. A. Smith and K. Struhl (ed.). 1994. Current protocols in molecular biology p. 2.4.1-2.4.5. Green Publishing Associates and Wiley-Interscience New York N.Y.

5. Bachellier S. E. Gilson M. Hofnung and C. W. Hill. 1996. Repeated sequences p. 2012-2040. In F. C. Neidhardt R. Curtiss III J. L. Ingraham E. C. C. Lin K. B. Low B. Magasanik W. S. Reznikoff M. Riley M. Schaechter and H. E. Umbarger (ed.) Escherichia coli and Salmonella : cellular and molecular biology 2nd ed. vol. 2. ASM Press Washington D.C.

Cited by 32 articles. 订阅此论文施引文献 订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献

同舟云学术

1.学者识别学者识别

2.学术分析学术分析

3.人才评估人才评估

"同舟云学术"是以全球学者为主线,采集、加工和组织学术论文而形成的新型学术文献查询和分析系统,可以对全球学者进行文献检索和人才价值评估。用户可以通过关注某些学科领域的顶尖人物而持续追踪该领域的学科进展和研究前沿。经过近期的数据扩容,当前同舟云学术共收录了国内外主流学术期刊6万余种,收集的期刊论文及会议论文总量共计约1.5亿篇,并以每天添加12000余篇中外论文的速度递增。我们也可以为用户提供个性化、定制化的学者数据。欢迎来电咨询!咨询电话:010-8811{复制后删除}0370

www.globalauthorid.com

TOP

Copyright © 2019-2024 北京同舟云网络信息技术有限公司
京公网安备11010802033243号  京ICP备18003416号-3