Linked Life Data

15663923

Source:http://linkedlifedata.com/resource/pubmed/id/15663923

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2005-1-24
pubmed:abstractText
Pyelonephritic Escherichia coli cause urinary tract infections that involve the kidneys. Initiation of infection is dependent on P-pili expressed on the bacterial surface. In this work, an essential interface for assembly of the helical rod structure of P-pili has been located on the major pilin subunit, PapA. Based on primary sequence alignment, secondary structure analysis, and quaternary structure modeling of the PapA subunit, we predicted the location of a site that is critical for in vivo assembly of the native macromolecular structure of P-pili. A rigid helical rod of PapA subunits comprising most of the pilus length is stabilized by n to n+3 subunit-subunit interactions, and is important for normal function of these pili. Using site-directed mutagenesis, ultrastructural analysis by electron cryomicroscopy, immunocytochemistry, and molecular modeling we show that residues 106-109 (Asn, Gly, Ala, Gly) are essential for assembly of native P-pilus filaments. Mutation of these residues disrupts assembly of the native P-pilus helix. Extended fibrillar structures do still assemble, verifying that n to n+1 subunit-subunit interactions are maintained in the mutant fiber morphology. Observation of this fibrillar morphology in the mutant fiber was predicted by our modeling studies. These mutant P-pili data validate the predictive value of our model for understanding subunit-subunit interactions between PapA monomers. Alteration of the pilus structure from a 7-8 nm helical rod to a 2 nm fibrillar structure may compromise the ability of these bacteria to adhere and remain bound to the host cell, thus providing a possible therapeutic target for antimicrobial drugs.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0022-2836
pubmed:author
pubmed:issnType
Print
pubmed:day
11
pubmed:volume
346
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
13-20
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
2005
pubmed:articleTitle
Localization of a critical interface for helical rod formation of bacterial adhesion P-pili.
pubmed:affiliation
Department of Physiology and Biophysics, Boston University School of Medicine, 715 Albany Street, Boston, MA 02118-2526, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't