title: Detection of conjugation related type four secretion machinery in Aeromonas culicicola.
abstract: BACKGROUND
  Aeromonas sp. can now be considered relatively common enteropathogens due to the increase of diseases in humans. Aeromonas culicicola is a gram negative rod-shaped bacterium isolated for the first time from the mosquito mid-gut, but subsequently detected in other insects and waters also. Our previous study discovered that A. culicicola harbors three plasmids, which we designated as pAc3249A, pAc3249B and pAc3249C. We investigated and report here the existence and genetic organization of a Conjugal Type IV Secretion System (TFSS) in pAc3249A.
  
  
  RESULTS
  The complete operon is 11,061 bp in length and has G+C content of 47.20% code for 12 ORFs. The gene order and orientation were similar to those found in other bacteria with some differences. We have designated this system as AcTra for Aeromonas culicicola transfer system. BLAST results of ORFs and phylogenetic analysis showed significant similarity towards the respective proteins of the IncI2 plasmid R721 of E. coli. Other bioinformatics studies have been performed to predict conserved motifs/domains, signal peptides, transmembrane helices, etc. of the ORFs.
  
  
  CONCLUSIONS
  BLAST results of ORFs and phylogenetic analysis showed significant similarity towards the respective proteins of the IncI2 plasmid R721 of E. coli.
authors.affiliation: Molecular Biology Unit, National Centre for Cell Science, Pune University Campus, Pune, Maharashtra, India.
authors.forename: Ashraf Yusuf
authors.initials: AY
authors.lastname: Rangrez
authors.forename: Kannayakanahalli Maheshwarappa
authors.initials: KM
authors.lastname: Dayananda
authors.forename: Santosh
authors.initials: S
authors.lastname: Atanur
authors.forename: Rajendra
authors.initials: R
authors.lastname: Joshi
authors.forename: Milind S
authors.initials: MS
authors.lastname: Patole
authors.forename: Yogesh S
authors.initials: YS
authors.lastname: Shouche
mesh_terms: D000333:Aeromonas / Q000235:genetics* / Q000302:isolation & purification / Q000472:pathogenicity / Q000502:physiology; D000818:Animals; D001426:Bacterial Proteins / Q000235:genetics / Q000502:physiology; D001482:Base Composition; D003227:Conjugation, Genetic / Q000502:physiology; D004926:Escherichia coli / Q000235:genetics; D036781:Fimbriae Proteins / Q000235:genetics / Q000502:physiology; D016905:Gram-Negative Bacterial Infections / Q000209:etiology; D006801:Humans; D043583:Nucleoside-Triphosphatase / Q000235:genetics / Q000502:physiology; D016366:Open Reading Frames; D009876:Operon; D010802:Phylogeny; D010957:Plasmids / Q000235:genetics; D013045:Species Specificity
chemical_list: D001426:Bacterial Proteins; D036781:Fimbriae Proteins; D043583:Nucleoside-Triphosphatase