legionella hackeliae legionella hackeliae legionella hackeliae is a gram-negative bacterium from the genus legionella which was isolated from human lung aspirate in pennsylvania. legionella hackeliae scientific classification domain: bacteria phylum: pseudomonadota class: gammaproteobacteria order: legionellales family: legionellaceae genus: legionella species: l. hackeliae binomial name legionella hackeliaebrenner et al. 1985 type strain atcc 35250, bibb lancing 2, ccug 31232 a, cip 103844, dsm 19214, gifu 10740, jcm 7563, nctc 11979