RT Journal Article SR Electronic(1) A1 Rhodes, Martha W. A1 Kator, Howard A1 McNabb, Alan A1 Deshayes, Caroline A1 Reyrat, Jean-Marc A1 Brown-Elliott, Barbara A. A1 Wallace, Richard A1 Trott, Kristin A. A1 Parker, John M. A1 Lifland, Barry A1 Osterhout, Gerard A1 Kaattari, Ilsa A1 Reece, Kimberly A1 Vogelbein, Wolfgang A1 Ottinger, Christopher A.YR 2005 T1 Mycobacterium pseudoshottsii sp. nov., a slowly growing chromogenic species isolated from Chesapeake Bay striped bass (Morone saxatilis) JF International Journal of Systematic and Evolutionary Microbiology, VO 55 IS 3 SP 1139 OP 1147 DO https://doi.org/10.1099/ijs.0.63343-0 PB Microbiology Society, SN 1466-5034, AB A group of slowly growing photochromogenic mycobacteria was isolated from Chesapeake Bay striped bass (Morone saxatilis) during an epizootic of mycobacteriosis. Growth characteristics, acid-fastness and 16S rRNA gene sequencing results were consistent with those of the genus Mycobacterium. Biochemical reactions, growth characteristics and mycolic acid profiles (HPLC) resembled those of Mycobacterium shottsii, a non-pigmented mycobacterium also isolated during the same epizootic. Sequencing of the 16S rRNA genes, the gene encoding the exported repeated protein (erp) and the gene encoding the 65 kDa heat-shock protein (hsp65) and restriction enzyme analysis of the hsp65 gene demonstrated that this group of isolates is unique. Insertion sequences associated with Mycobacterium ulcerans, IS2404 and IS2606, were detected by PCR. These isolates could be differentiated from other slowly growing pigmented mycobacteria by their inability to grow at 37 °C, production of niacin and urease, absence of nitrate reductase, negative Tween 80 hydrolysis and resistance to isoniazid (1 μg ml−1), p-nitrobenzoic acid, thiacetazone and thiophene-2-carboxylic hydrazide. On the basis of this polyphasic study, it is proposed that these isolates represent a novel species, Mycobacterium pseudoshottsii sp. nov. The type strain, L15T, has been deposited in the American Type Culture Collection as ATCC BAA-883T and the National Collection of Type Cultures (UK) as NCTC 13318T., UL https://www.microbiologyresearch.org/content/journal/ijsem/10.1099/ijs.0.63343-0