Captivus acidiprotistae Baker et al. 2003 Baker B.J. Hugenholtz P. Dawson S.C. Banfield J.F. Extremely acidophilic protists from acid mine drainage host Rickettsiales-lineage endosymbionts that have intervening sequences in their 16S rRNA genes. 2003 69 9 5512 8 Applied and Environmental Microbiology Appl Environ Microbiol 0099-2240 1098-5336 10.1128/AEM.69.9.5512-5518.2003 12957940