Table 2

Complete genomes where Trp-pathway genes were lost via reductive evolution

Bacterial organisms
No pathway
Incomplete pathway

Bdellovibrio bacteriovorus


Borrelia burgdorferi


Chlamydia muridarum


Chlamydia trachomatis


Chlamydophila pneumoniae


Chlamydophila psittacia


Clostridium difficile


Clostridium perfringens


Clostridium tetani


Coxiella burnetti


Enterococcus faecalis


Fusobacterium nucleatum


Haemophilus ducreyi


Lactobacillus johnsonii


Mycoplasma genitalium


Mycoplasma mycoides


Mycoplasma pneumoniae


Phytoplasma asteris


Porphyromonas gingivalis


Rickettsia prowazekii


Streptococcus agalactiae


Streptococcus equi


Streptococcus pyogenes


Treponema denticola


Treponema pallidum


Tropheryma whipplei


Ureaplasma urealyticum


Wigglesworthia glossinidiab


Wolbachia sp.b


Yesinia pestis KIM



aBut see [10] for a description of how an incomplete Trp pathway has been joined with other genes to yield a mosaic operon with a novel function. bInsect endosymbiont.

Xie et al. BMC Biology 2004 2:15   doi:10.1186/1741-7007-2-15