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PMID: 15546668 Published · ppublish English Journal Article Research Support, U.S. Gov't, P.H.S. Review

Type IV secretion: the Agrobacterium VirB/D4 and related conjugation systems.

Biochimica et biophysica acta ·Vol. 1694 ·No. 1-3 ·2004-11-11 ·Pages 219-34

Christie PJ

Abstract

The translocation of DNA across biological membranes is an essential process for many living organisms. In bacteria, type IV secretion systems (T4SS) are used to deliver DNA as well as protein substrates from donor to target cells. The T4SS are structurally complex machines assembled from a dozen or more membrane proteins in response to environmental signals. In Gram-negative bacteria, the conjugation machines are composed of a cell envelope-spanning secretion channel and an extracellular pilus. These dynamic structures (i) direct formation of stable contacts-the mating junction-between donor and recipient cell membranes, (ii) transmit single-stranded DNA as a nucleoprotein particle, as well as protein substrates, across donor and recipient cell membranes, and (iii) mediate disassembly of the mating junction following substrate transfer. This review summarizes recent progress in our understanding of the mechanistic details of DNA trafficking with a focus on the paradigmatic Agrobacterium tumefaciens VirB/D4 T4SS and related conjugation systems.

MeSH Terms
Amino Acid Sequence Bacterial Proteins/genetics,metabolism,physiology Biological Transport/physiology Conjugation, Genetic/physiology DNA, Bacterial/metabolism Fimbriae, Bacterial/physiology Membrane Transport Proteins/genetics,physiology Molecular Sequence Data Operon Rhizobium/genetics,physiology Virulence Factors/physiology
Chemicals
Bacterial Proteins DNA, Bacterial Membrane Transport Proteins Virulence Factors
Authors & Affiliations
1 authors, click to expand affiliations / ORCID
Christie Peter J
Department of Microbiology and Molecular Genetics, UT-Houston Medical School, 6431 Fannin, JFB1.765, Houston TX 77030, USA. [email protected] <[email protected]>
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Article Info
Journal
Biochimica et biophysica acta
Abbr.
Biochim Biophys Acta
ISSN
0006-3002
Published
2004-11-11
Pages
219-34
Language
English
Region
Netherlands
NLM ID
0217513
PMCID
PMC4845649
Subset
IM
Grants
NIGMS NIH HHS · R01 GM048746 · United States
NIGMS NIH HHS · GM47846 · United States
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