@article{mbs:/content/journal/ijsem/10.1099/ijs.0.02514-0, author = "Tomaszewski, Elizabeth K. and Logan, Kathleen S. and Snowden, Karen F. and Kurtzman, Cletus P. and Phalen, David N.", title = "Phylogenetic analysis identifies the ‘megabacterium’ of birds as a novel anamorphic ascomycetous yeast, Macrorhabdus ornithogaster gen. nov., sp. nov.", journal= "International Journal of Systematic and Evolutionary Microbiology", year = "2003", volume = "53", number = "4", pages = "1201-1205", doi = "https://doi.org/10.1099/ijs.0.02514-0", url = "https://www.microbiologyresearch.org/content/journal/ijsem/10.1099/ijs.0.02514-0", publisher = "Microbiology Society", issn = "1466-5034", type = "Journal Article", keywords = "PNA, peptide nucleic acid", keywords = "D1/D2, domains 1 and 2", keywords = "PAS, periodic acid–Schiff", abstract = "An organism commonly referred to as ‘megabacterium’ colonizes the gastric isthmus of many species of birds. It is weakly Gram-positive and periodic acid–Schiff-positive and stains with silver stains. Previous studies have shown that it has a nucleus and a cell wall similar to those seen in fungi. Calcofluor white M2R staining suggests that the cell wall contains chitin, a eukaryote-specific substance, and rRNA in situ hybridization demonstrates that it is a eukaryote. To characterize this organism phylogenetically, DNA was extracted from purified cells. rDNA was readily amplified by PCR with pan-fungal DNA primer sets and primer sets derived from the newly determined sequence, but not with bacteria-specific primer sets. Specific primer sets amplified rDNA from isthmus scrapings from an infected bird, but not from a non-infected bird or other control DNA. The sequence was confirmed to derive from the purified organism by in situ rRNA hybridization using a specific probe. Phylogenetic analysis of sequences of the 18S rDNA and domain D1/D2 of 26S rDNA showed the organism to be a previously undescribed anamorphic ascomycetous yeast representing a new genus. The name Macrorhabdus ornithogaster gen. nov., sp. nov. is proposed for this organism. The type material is CBS 9251T (=NRRL Y-27487T).", }