Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0231530 (twitching)
 2,043 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Adherence of enteropathogenic Escherichia coli (EPEC) to epithelial cells is dependent on a type IV fimbria, termed the bundle-forming pilus (BFP). A cluster of 14 genes is required for expression of BFP. The eighth gene in the cluster, bfpF, encodes a putative nucleotide-binding protein which resembles the PilT protein of Pseudomonas aeruginosa. It has been proposed that PilT is required for the retraction of the P. aeruginosa pilus, which results in twitching motility. To test the role of BfpF in BFP function and EPEC pathogenesis, two different mutations were constructed in the bfpF gene, one in the cloned gene cluster in a laboratory E. coli strain and one in wild-type EPEC. Neither mutation affected prepilin synthesis, leader sequence processing, or pilus biogenesis. However, both mutations resulted in increased localized adherence. In addition, the EPEC bfpF mutant displayed increased aggregation. The EPEC bfpF mutant was not deficient in attaching and effacing activity or invasion capacity. These results suggest that BfpF decreases aggregation and adherence by EPEC but that subsequent steps in EPEC pathogenesis do not require this protein.
 ...
PMID:Role of BfpF, a member of the PilT family of putative nucleotide-binding proteins, in type IV pilus biogenesis and in interactions between enteropathogenic Escherichia coli and host cells. 942 48

Type IV pili (T4P) are ubiquitous bacterial cell surface structures, involved in processes such as twitching motility, biofilm formation, bacteriophage infection, surface attachment, virulence, and natural transformation. T4P are assembled by machinery that can be divided into the outer membrane pore complex, the alignment complex that connects components in the inner and outer membrane, and the motor complex in the inner membrane and cytoplasm. Here, we characterize the inner membrane platform protein PilC, the cytosolic assembly ATPase PilB of the motor complex, and the cytosolic nucleotide-binding protein PilM of the alignment complex of the T4P machinery ofMyxococcus xanthus PilC was purified as a dimer and reconstituted into liposomes. PilB was isolated as a monomer and bound ATP in a non-cooperative manner, but PilB fused to Hcp1 ofPseudomonas aeruginosaformed a hexamer and bound ATP in a cooperative manner. Hexameric but not monomeric PilB bound to PilC reconstituted in liposomes, and this binding stimulated PilB ATPase activity. PilM could only be purified when it was stabilized by a fusion with a peptide corresponding to the first 16 amino acids of PilN, supporting an interaction between PilM and PilN(1-16). PilM-N(1-16) was isolated as a monomer that bound but did not hydrolyze ATP. PilM interacted directly with PilB, but only with PilC in the presence of PilB, suggesting an indirect interaction. We propose that PilB interacts with PilC and with PilM, thus establishing the connection between the alignment and the motor complex.
...
PMID:The Type IV Pilus Assembly ATPase PilB of Myxococcus xanthus Interacts with the Inner Membrane Platform Protein PilC and the Nucleotide-binding Protein PilM. 2685 Dec 83