Isolation and characterization of novel mycobacteria species from Sarracenia purpurea

Abstract

Several fast to intermediate growing acid-fast, scrotochromogenic bacteria were isolated from Sarracenia purpurea pitcher waters in Minnesota sphagnum peat bogs. The isolates were identified by a polyphasic approach using morphological, biochemical, and bioinformatic techniques. Phylogenetic studies indicate the strains are located in the Mycobacterium genus with no obvious relation to any characterized type strains of mycobacteria. Two distinct clades emerged among the pitcher plant isolates, therefore two type strains (DL734 and DL739) were designated to represent the two clades. Phenotypic characterization revealed neither strain is similar to known genus type strains in collective properties of growth, pigmentation, or enzyme synthesis. Fatty acid methyl ester (FAME) profiles were unique for each type strain. The two isolates showed the unique ability to survive temperatures as low as 8°C. DL734 appeared to enter a viable but non-culturable state while DL739 appeared to be psychrotolerant. This could indicate that mycobacteria are more plastic in their ability to withstand different abiotic factors than previously recognized. The names Mycobacterium purpureae sp. nov. and Mycobacterium helvus sp. nov. are proposed for type strains DL734 (=JSM 30395 =NCCB 100519T) and DL739 (=JSM 30396=NCCB 100520T), respectively.