title: Identification of horizontally transferred genes in the genus Colletotrichum reveals a steady tempo of bacterial to fungal gene transfer.
abstract: BACKGROUND
  Horizontal gene transfer (HGT) is the stable transmission of genetic material between organisms by means other than vertical inheritance. HGT has an important role in the evolution of prokaryotes but is relatively rare in eukaryotes. HGT has been shown to contribute to virulence in eukaryotic pathogens. We studied the importance of HGT in plant pathogenic fungi by identifying horizontally transferred genes in the genomes of three members of the genus Colletotrichum.
  
  
  RESULTS
  We identified eleven HGT events from bacteria into members of the genus Colletotrichum or their ancestors. The HGT events include genes involved in amino acid, lipid and sugar metabolism as well as lytic enzymes. Additionally, the putative minimal dates of transference were calculated using a time calibrated phylogenetic tree. This analysis reveals a constant flux of genes from bacteria to fungi throughout the evolution of subphylum Pezizomycotina.
  
  
  CONCLUSIONS
  Genes that are typically transferred by HGT are those that are constantly subject to gene duplication and gene loss. The functions of some of these genes suggest roles in niche adaptation and virulence. We found no evidence of a burst of HGT events coinciding with major geological events. In contrast, HGT appears to be a constant, albeit rare phenomenon in the Pezizomycotina, occurring at a steady rate during their evolution.
authors.forename: Vinicio D Armijos
authors.initials: VD
authors.lastname: Jaramillo
authors.forename: Serenella A
authors.initials: SA
authors.lastname: Sukno
authors.affiliation: Instituto Hispano-Luso de Investigaciones Agrarias (CIALE), Departamento de Microbiología y Genética, Universidad de Salamanca, Villamayor, Spain. mthon@usal.es.
authors.forename: Michael R
authors.initials: MR
authors.lastname: Thon
mesh_terms: D001419:Bacteria / Q000235:genetics*; D020231:Colletotrichum / Q000235:genetics* / Q000502:physiology; D030562:Databases, Protein; D017353:Gene Deletion; D020440:Gene Duplication; D022761:Gene Transfer, Horizontal; D005798:Genes, Bacterial; D005800:Genes, Fungal; D010802:Phylogeny