title: Legionella steelei sp. nov., isolated from human respiratory specimens in California, USA, and South Australia.
abstract: Legionella-like bacteria were isolated from the respiratory tract of two patients in California, USA, and South Australia, but were not thought to cause disease. These bacteria, strains F2632 and IMVS-3376(T), were found to have identical Legionella macrophage infectivity potentiator (mip) gene sequences and were therefore further characterized to determine their genetic and phenotypic relatedness and properties. Both of these Gram-negative-staining bacterial strains grew on buffered charcoal yeast extract medium, were cysteine auxotrophs and made a characteristic diffusible bright yellow fluorescent pigment, with one strain making a late appearing colony-bound blue-white fluorescent pigment. The optimal in vitro growth temperature was 35 °C, with very poor growth at 37 °C in broth or on solid media. There was no growth in human A549 cells at either 35 or 37 °C, but excellent growth in Acanthamoeba castellani at 30 °C and poorer growth at 35 °C. Phylogenetic analysis of these bacteria was performed by sequence analysis of 16S rRNA, mip, ribonuclease P, ribosomal polymerase B and zinc metalloprotease genes. These studies confirmed that the new strains represented a single novel species of the genus Legionella for which the name Legionella steelei sp. nov. is proposed. The type strain is IMVS-3376(T) ( = IMVS 3113(T) = ATCC BAA-2169(T)).
authors.affiliation: University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA.
authors.forename: Paul H
authors.initials: PH
authors.lastname: Edelstein
authors.affiliation: University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA.
authors.forename: Martha A
authors.initials: MA
authors.lastname: Edelstein
authors.affiliation: Microbiology and Infectious Diseases Laboratories, Institute of Medical and Veterinary Science, SA Pathology, Adelaide, Australia.
authors.forename: Lisa J
authors.initials: LJ
authors.lastname: Shephard
authors.affiliation: UCLA Health System Clinical Laboratories-Microbiology, Los Angeles, CA, USA.
authors.forename: Kevin W
authors.initials: KW
authors.lastname: Ward
authors.affiliation: School of Biomedical Science, The University of Adelaide, Adelaide, Australia.|Microbiology and Infectious Diseases Laboratories, Institute of Medical and Veterinary Science, SA Pathology, Adelaide, Australia.
authors.forename: Rodney M
authors.initials: RM
authors.lastname: Ratcliff
mesh_terms: D000328:Adult; D002140:California; D002460:Cell Line; D004269:DNA, Bacterial / Q000235:genetics; D005838:Genotype; D006801:Humans; D007875:Legionella / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification*; D008297:Male; D008969:Molecular Sequence Data; D010802:Phylogeny; D010858:Pigmentation; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012137:Respiratory System / Q000382:microbiology*; D017422:Sequence Analysis, DNA; D013021:South Australia; D013696:Temperature
chemical_list: D004269:DNA, Bacterial; D012336:RNA, Ribosomal, 16S